| Action Date |
Action |
Description |
DEC Staff |
| 1/6/1978 |
Update or Other Action |
See further actions concerning this matter at Elmendorf OU5 SD40, ST46, SS53 CS DB Reckey# 198921X136415.
ADF&G Memo Diagnostic/Inspection Report at the Ship Creek Hatchery by Kent Hauck Regional Fish Health Specialist- person contacted Lee Ohlinger. On January 4, 1978, a residue mixture of Jet-A 50 fuel & aircraft lube oil surfaced in gallery 1 during a routine water flow check using fluorescein dye. The fuel mixture with the dye passed separately through the cooling ponds containing 6,400 brood stock rainbow trout (Salmo gairdneri) & the raceways containing 818,000 fingerling chinook salmon (Oncorhynchus tshawytsca). A sample of the chinook examined on January 6, 1978 showed no pathological effects.
Daily mortalities of chinook from January 6 to the present have been approximately 0.057%, which is normal for this facility (fish hatchery). The extent of exposure of the fuel to the fish is unknown since the concentration of the contaminant as it enters the gallery is not known, On the day of the exposure, the gallery was emptied by pumping stream water & groundwater from the gallery at 1,200 gpm for approximately 45 minutes. The possible impact of the presence of these pollutants in the hatchery system should be evaluated. It has been postulated that if exposure to hydrocarbon fuels is not extensive, long term biological effects will not occur.
If exposure lasts a few days, uptake of the contaminants in fish will occur. After the fish have been in clean water several weeks after exposure, however, hydrocarbon contaminants are very difficult to detect analytically. The concentration of fuel contaminant in Ship Creek was possibly much lower than 100 ppm. In addition, a fish kill soon after exposure should have occurred had the concentration of the contaminants been sufficient, since jet fuels are highly volatile & toxic.
NOTE TO FILE: Naphthalene is a white solid or a liquid that occurs naturally in fossil fuels such as coal & crude oil & is best known as the primary ingredient of mothballs. It is extracted from these sources for other uses including jet fuel (as 1-3% of the fuel JP-4, JP-8, & commercial aviation gas or AvGas). |
Jennifer Roberts |
| 11/2/1983 |
Update or Other Action |
USAF William R. Hanson, P.E. Director, Engrg. & Envmtl. Planning to DEEV (Mr. Hostman) 21 CSG/DEEV RE: Memorandum of Understanding (MOU) between DOD and EPA.
1. The attached guidance has been received from HQ USAF/LEE (atch 1). It is subject to change as time progresses. It is important to note that all actions affected by this agreement will be implemented within the overall guidance of the Installation Restoration Program.
2. All queries or requests for action received from Federal or State agencies concerning releases from former Air Force installations (MOU para 3.2) or other releases for which the Air Force is a responsible party(MOU para 3.3) will be referred to HQ AAC/DEEV for forwarding to HQ USAF/LEEV. HQ USAF will task appropriate commands and/or staff agencies for response action. Any requests received from the State of Alaska or other Federal agencies will be reported by phone to this office, autovon 552-4151. All pertinent information will be provided to assist HQ AAC/DEEV in determining the exact nature of the information requested and required for the reply. The information requested will include any information on pending legislation or other enforcement actions that may have an effect on the situation.
Letter from Gary Alkire Brigadier General USAF Deputy Director, Directorate of Engineering & Services to ALMAJCOM/DE/SG/JA.
1. The attached MOU regarding implementation of the Comprehensive Environmental Response, Compensation, and Liability Act of 1980 is provided for your information. It deals, in general, with DoD and EPA responsibilities and procedures to be followed in identifying, evaluating, and controlling releases of hazardous pollutants from currently active and former DoD facilities and third party facilities at which DoD is a responsible party.
2. This letter provides interim implementation guidance concerning the MOU.
3. All Air Force actions in response to this MOU will be conducted within the framework of the existing Installation Restoration Program.
4. Affected major commands will continue to be responsible for releases from currently active Air Force installations (MOU para 3.1).
5. All queries or requests for action received from Federal or State agencies concerning releases from former Air Force installations (MOU para 3.2) or other releases for which the Air Force is a responsible party (MOU para 3.3) will be referred to HQ USAF/LEEV. HQ USAF will task appropriate commands and/or staff agencies for response action. See site file for additional information. |
Louis Howard |
| 3/17/1986 |
Update or Other Action |
In the 1980s, contaminated groundwater emanating from the bluff as seeps along the southern
border of JBER-Elmendorf provided the first indication of contaminated groundwater. Several
Base-wide investigations occurred during the late 1980 under the Installation Restoration
Program (IRP; now known as the Environmental Restoration Program [ERP]). This investigation included Phase II–Stage 1 efforts conducted in 1985. Final Report, Installation Restoration Program Phase II— Confirmation/Quantification Stage 1, Elmendorf AFB.
The Elmendorf AFB Phase II, Stage 1 field evaluation of the IRP investigated 11 sites
through drilling, installing, and sampling 19 new monitoring wells and grab sampling in a
wetland.
Two ground water systems exist beneath the base, and they are typically separated by a
thick clay unit. The depth to water table varies from zero to as much as 50 to 60 feet.
The shallow aquifer has been contaminated in the past and is vulnerable to future contamination,
but the deeper aquifer is not in significant danger. The principal source of water for
the base and the adjacent City of Anchorage is surface water upstream of the base; makeup
wells generally extend to the deep aquifer.
Parameters for which there are no enforceable standards indicate contamination of the
shallow aquifer at the base. Oil and grease, specific conductance, pH, TOX, TOC, and lead
at various sites indicate there has been some water quality degradation at Elmendorf AFB.
Soils have also been found to be contaminated with oil and grease. Additional analyses and
investigations are recommended to confirm and define the indicated contamination. |
Louis Howard |
| 8/2/1988 |
Update or Other Action |
CERCLA Operable Units' source areas that correspond to RCRA SWMUs from the RCRA RFA. Spill Sites: ST37 SP-1 Diesel Fuel Leak- South of the Corps of Engineers BId just over the bluff. Three underground product lines lie south of the Corps bId. with lines running northeast- southwest and parallel to the crest.
This site was the location of a fuel leak of thousands of gallons diesel during 1956-1958, the majority of the fuel was recovered but unknown quanitities of fuel may stil be present. The site has a low priority for investigation due to age of the spill and the recovered amount. However the Ship Creek investigation may look into this site as part of its investigation, in the RFI workplan. |
Louis Howard |
| 9/2/1988 |
Update or Other Action |
Engineering-Science (1983), in the IRP Phase I, Records Search, indicated Building 21-900 is an automotive maintenance facility which is used to maintain most vehicles on base. A series of floor drains is connected to 2 sumps that used to drain into a seepage pit north of the building. Spilled petroleum products and PD-680 used in vehicle cleaning operations have been washed into the drains.
Currently, the sumps discharge to a storm drain. The floor drains from the mechanical room still still discharge to the seepage pit. A catch basin on the south side of the building also runs to the seepage pit (Ritz, USAF, personal communication, 08 March 1989). In 1988, Black & Veatch (1990) placed a soil boring, collected soil samples at 15 feet and 20 feet below ground surface, and finished the boring as a monitoring well (IS7-01) for site IS-7 Floor Drain at Building 21-900. After these activities, a water sample was collected from the monitoring well.
The groundwater sample was contaminated with chloroform at 0.32 ug/L and trichloroethene at 76 ug/L. These levels are above the drinking water MCLs. TPH level was 2,000 ug/L. Because of the position of the monitoring well relative to the dry well, sumps, and other potential sources, the contamination detected in the groundwater may not be representative of potential contamination from the source. Black & Veatch (1990) estimated that the direction of groundwater flow was from the north to the south.
If that is accurate, the well may be located upgradient of SD30 sources. |
Louis Howard |
| 10/20/1989 |
Update or Other Action |
ADEC Ron Klein, Supervisor, Contaminated Site Investigations, sent letter to Captain Brad Gerken, Dept. of Air Force, 5099th Civil Engineering Operations Squadron (AAC) Subject: Response to September 27, 1989 Letter; Requirements for Temporary Storage of Petroleum Contaminated Soil. Enclosed is a copy of the Southcentral Region Office's interim policy for storage and disposal of waste oil contaminated soil.
The guidance also applies to storage of soils contaminated with clean fuels if they are to be stored off the site where they were generated or stored on-site longer than thirty (30) days. The guidance document will be revised shortly to make that explicit. Petroleum contaminated soils generated on-site and stockpiled onsite for less than thirty (30) days must be placed on a bermed liner and covered. The liner and cover must be at least 6 mil reinforced polyethylene.
Alaska Department of Environmental Conservation Southcentral Region Office - Interim Policy For Storage and Disposal of Waste Oil Contaminated Soil
The Southcentral Regional Office solid waste program has been working on an interim policy for storage and disposal of waste oil contaminated soil. Currently the Region has approved the removal of waste oil contaminated soil to a facility permitted to properly handle the contamination. With the exception of the Municipality of Anchorage (MOA) Landfill and Alaska Pollution Control Palmer Facility (pre-treatment for landfill disposal) all of these
facilities are located in the contiguous United States.
Currently, if the waste oil contaminated soil does not meet MOA Landfill criteria the only disposal option is to send the contaminated soil out of Alaska. Soil disposal under this method is costly due to handling, shipping, and facility fees. In discussions with Responsible Parties (RP) there appears to be a strong move to develop other local disposal methods that would meet with agency approval. Therefore the Regional solid waste program has developed interim storage guidelines for waste oil contaminated soils.
These guidelines include the following:
1. An approved design for a low-maintenance or maintenance free storage liner and cover that will be able to withstand winter conditions and is petroleum resistant. This will include a schedule to monitor the storage facility to verify that the integrity of the liner and cover is maintained throughout the storage period.
2. Obtain a solid waste storage plan approval for onsite storage of waste oil contaminated soil from ADEC prior to storage construction.
3. The Responsible Party may propose to remove the waste oil contaminated soil to an off-site storage location if long term on-site storage is not practical. This location must be approved of by the Department prior to any transfer of the soils. The storage site must meet, ADEC design criteria and the RP must obtain an off-site; solid waste storage plan approval prior to transfer of the soil. All transfer of soil off-site must be done under a Bill of Lading and copies provided to ADEC.
4. The maximum allowable storage time is one (1) year. |
Ron Klein |
| 12/30/1989 |
Site Added to Database |
Petroleum contaminants and solvents. |
Louis Howard |
| 2/19/1990 |
Meeting or Teleconference Held |
On 16 February 1990, a meeting was held to discuss Alaska Department of Environmental Conservation (ADEC) Stage 3 RI/FS & Stage 4 Work Plan review comments in their 15 November 1989 & 29 December 1989 letters. Those in attendance were:
Maj Lindsey C. Waterhouse Air Force
Capt Russell K. Godsave (Recorder) Air Force
lLt Walter Migdal Air Force/OEHL
Mr Glenn Brown Air Force
Ms Susan A. Curtin Black & Veatch
Mr Doug Johnson EPA
Mr Ron Klein ADEC
Mr Vernon M. Reid Black & Veatch
Ms Jennifer L. Roberts ADEC
Mr Howard Weaver Air Force
Mr Joseph Williamson Air Force
Page 1, GENERAL COMMENT #1: State mentions "several sites"; we requested in the future that the State identify sites. The 1000 mg/kg TPH level was noted by the State of Alaska (State) to be a Municipality of Anchorage (MOA) landfill requirement only. It was suggested that Mr Mike Blair of the MOA be contacted in relationship to the MOA landfill accepting "mass balance" of soil
to meet turn-in requirements. In relationship to this, Mr Doug Johnson noted that off-site disposal, as in the case of the MOA landfill, may include certain potential liabilities & the Air Force should be aware of these.
Both the State & EPA stated that it may be better to treat contaminated soils on base. Mr Williamson reinforced this, stating that pretreatment of soil will always be considered for each operable unit. The California "LUFT Manual" was noted by Major Waterhouse as guidance the State should consider adopting. In addition, the Air Force requested that State guidance be clear & promulgated. The State added the Air Force should strive for 100 ppm TPH for nongasoline removal or treatment.
Page 1, GENERAL COMMENT #2: The State requested seasonal sampling, they said, to get a better picture of hydrologic data, especially along Ship Creek. The intent is seasonal water level sampling, not full analytical sampling. In addition, the seasonal water sampling is intended to give us a good baseline for the future. The Air Force agreed. Seasonal sampling was
noted to be two periods: our dry & wet seasons.
Page 2, GENERAL COMMENTS #3 & #4: The Air Force & the contractor plan to take a minimum of two samples per boring. More will be taken as needed. The State & EPA indorsed collecting samples for routine laboratory analysis at every 2 to 5-foot interval of the bore holes in preference to using an HNu to screen the split spoon sample & sampling only those levels where a positive HNu reading was obtained.
Page 2, GENERAL COMMENT #5: Again, the State mentions "many sites"; request in the future that State identify sites. Also, as discussed in the meeting, the contractor has based the location of new wells on logical data. The well locations, however, are general & will be sited more precisely as the study continues.
Page 2, GENERAL COMMENT #6: Although it was agreed upon that a possible route of contamination exists along well casings, at least the Air Force & contractor felt this risk was, at best, minimal. Still, Major Waterhouse pointed out that Bioenvironmental Engineering monitors all deep aquifer potable water wells. To date, no signs of contamination has been noted. Well
#1 is a 16-foot shallow well (cistern) collecting water from the shallow aquifer. The identified volatile organic contaminants in this well are not indicative of the deep water aquifer water quality.
Page 3, GENERAL COMMENT #7: Capt Godsave asked the State what an "approved oil/water separator" was & what regulations are entailed. The State elected to defer their answer. Mr Johnson noted that this was a NPDS or RCRA issue & not a CERCLA issue. Major Waterhouse noted that a team from Occupational & Environmental Health Laboratory (OEHL) are coming to Elmendorf AFB soon to achieve an inventory of floor drains as requested by the State. The State requested that the OEHL team discuss their methodology with the State up front. Major Waterhouse agreed to this.
Page 3, GENERAL COMMENT #8: The State stated this comment was essentially for our information. Both the State & EPA stated that a industrial waste water permit is not required for the storm sewers, but that the Air Force should meet the intent of such a permit.
Page 3, GENERAL COMMENT #9: The Air Force has asked the contractor to better define & consistently use the terms "off-site" & "off-installation," & be more definitive on the potential for contamination migration. Contaminant migration should only be inferred when enough
technical data has been obtained to support such a statement.
Page 3, SITE IS-1: It was noted that the contractor will use product probes in the future to identify floating product. |
Ron Klein |
| 5/28/1990 |
Update or Other Action |
Final Report, Installation Restoration Program Stage 3 Remedial Investigation/Feasibility Study, EAFB received. A field investigation program was conducted at 32 IRP sites to provide data to identify & characterize contaminants. Of the 32 IRP sites investigated, 7 require no further action, 18 require further investigation, & a feasibility study was completed to evaluate remedial actions for the remaining 7 sites.
In addition to the soil gas survey, the following visual observations were made in the field while drilling the wells:
- Well SP-01 - An HNu reading of 17 ppm was taken on a soil sample at 5'. A petroleum odor was present.
- Well SP1-02 - The following HNu readings were taken on soil samples:
40' - 17 ppm (odor)
42' - 45 ppm (odor)
47' - 12 ppm (slight odor)
50' - 20 ppm (slight odor)
Contamination by volatile organic compounds was encountered at Site SP-1. Specifically, benzene, toluene, ethylbenzene, & xylenes (BETX) were identified in a water sample from the site. Total BETX in water from well SP1-01 was 192.8 ug/L. TPH in this sample was 160 mg/L. Soil samples taken during drilling of this well were not contaminated. However, soil collected during the drilling of well SP1-02 was contaminated with petroleum hydrocarbons (400 mg/kg) at 50 feet. A water sample from well SP1-02 also contained petroleum hydrocarbons (5.0 mg/L) & ethylbenzene (1.4 ug/L).
Analytical methods detected organic compounds & petroleum hydrocarbons in soil & water samples from Site SP-1. Benzene was detected in water from SP1-01 at 13 ug/L which exceeds the State of AK Primary Drinking Water Standard of 5 ug/L.
Toluene & ethylbenzene levels detected were below the regulatory limits. However, since water samples from wells SP1-01 & SP1-02 had petroleum odors & sheen, State of AK Drinking Water Standards for petroleum hydrocarbons were also exceeded.
Petroleum hydrocarbons from boring SP1-02, at a concentration of 400 mg/kg, exceeding the level suggested by the interim State of AK soil cleanup guidelines. The source of petroleum hydrocarbons & associated volatile organics in the soil & water at this site is probably from leaks in the 3 underground POL & diesel lines adjacent to the site. The specific types & quantity of fuels spilled was never recorded. Pathways of exposure are contact with & ingestion or uptake of contaminated ground or surface water. Receptors of the contamination are humans, wildlife, fish & plants.
A soil gas survey showed detectable BTX contamination over most of the site. Benzene was not detected at any of the soil gas probe locations, but toluene & xylenes were pervasive, especially at the base of the bluff north of the railroad.
Two areas of unidentified organic contamination were also detected during the survey. Lab analyses of the water samples collected from wells SP1-01 & SP1-02 confirm the soil gas results for BTX contamination; both petroleum hydrocarbons & fuel related volatile organics were detected in water from both wells. Soil contaminated by petroleum hydrocarbons was only detected in samples from SP1-02. A small pond located immediately to the west of SP1-01 had a visible sheen in water that also had a petroleum smell. This water was not sampled or analyzed.
Petroleum hydrocarbons & volatile organics are probably migrating in the GW. However, there are no wells downgradient from wells SP1-01 & SP1-02. The extent of migration past wells SP1-01 & SP1-02 is not known. However, the POL pipelines that are reportedly responsible for contamination at the site are upgradient from both SP1-01 & SP1-02. Therefore, the presence of detectable contamination in these wells & in the soil gas survey indicate a downgradient migration pattern.
The site is close to a visually contaminated pond & privately-owned railroad tracks. There is potential for liability if contamination has spread under the tracks. Site SP-1 is recommended for high priority status due to the concentrations of petroleum hydrocarbons & benzene in water samples from this site.
Further work should include groundwater field screening probes in the area south of the railroad tracks & north of the POL pipelines. The survey will help to better define plume dimensions & will aid in selection of additional monitoring well locations. Five wells would be needed at this site.
The previous 2 wells should be sampled. The water samples should be analyzed for total petroleum hydrocarbons, purgeable aromatics & purgeable halocarbons. Purgeable halocarbons are not normally associated with diesel fuels, yet the soil gas survey detected unidentified organics which may be solvents. In addition, water samples should be collected from the contaminated pond. These samples should also be analyzed for petroleum hydrocarbons, purgeable aromatics & purgeable halocarbons. The soils collected from the new borings should be analyzed for TPH & VOCs. |
Louis Howard |
| 10/31/1991 |
Update or Other Action |
CH2MHILL site summary (ANC31026.D6.10) recommended that source ST37 be addressed as a high priority source area due to the potential off source contaminant migration and risk to human health and the environment. Further investigation is warranted at this source. In addition to soil and groundwater samples, surface water samples or soil/sediment samples should be taken from the pond at Source ST37. Finally, depending on the results of the delineation of contamination south of the source, consideration should be given to sampling Ship Creek. Also, explanation is needed to account for the fact that benzene was detected in the groundwater at levels exceeding MCLs whereas benzene wasn't detected by the soil probe. |
Jennifer Roberts |
| 11/12/1991 |
Enforcement Agreement or Order |
Federal Facility Agreement under Comprehensive Environmental Response, Compensation, and Liability Act (CERCLA) signed for docket # 1089-07-19-120. The agreement ensures that the environmental impacts associated with past and present activities at the Base are thoroughly investigated and appropriate removal and/or remedial action(s) taken as necessary to protect human health and the environment. Elmendorf Federal Facility Agreement signed.
The general purposes of this Agreement are to: (a) Ensure that the environmental impact associated with past and present activities at the Site are thoroughly investigated and appropriate removal and/or remedial action(s) taken as necessary to protect the public health, welfare, and the environment.(b) Establish a procedural framework and schedule for developing, implementing, and monitoring appropriate response actions at the Site in accordance with CERCLA, the NCP, Superfund guidance and policy, RCRA, RCRA guidance and policy, and applicable state law.
The FFA divided the CERCLA study source areas at Elmendorf AFB into the following seven operable unites (OUs), on the basis of geographic proximity and similar source characteristics or contaminants:
- OU1 Landfills (LF05, LF07, LF13, LF59, OT56)
- OU2 Tank Spill Sites (ST20, ST41, including the ST41 Sludge Disposal Area)
- OU3 Central Containment Area (SD16, SD31, SD52, SS21)
- OU4 Northern Containment Area (SD24, SD25, SD28, SD29, FT23, SSl0)
- OU5 Southern Containment Area (ST37)
- OU6 Surface Disposal Sites (LF02, LF03, LF04, SD15, SD73, WP14)
- OU7 Limited Field Investigation (SS19)
Proposed listing on NPL was 07/14/1989 and Final listing on NPL was on 08/30/1990.
See site file for additional information.
|
Jennifer Roberts |
| 11/12/1991 |
Update or Other Action |
Jennifer Roberts Federal Facility Coordinator sent letter to Joe Williamson and Rich Howard pursuant to Section 9.1 of the Elmendorf Air Force Base Federal Facility Agreement (FFA). ADEC designates Jennifer Roberts as the Project Manager and Ron Klein as the Alternate Project Manager for all activities covered under the FFA. |
Jennifer Roberts |
| 12/30/1991 |
Update or Other Action |
EPA sent letter to AF Rich Howard and Joe Williamson. The notification will serve as an addendum to the previous letter of November 4, 1991 which designates the USEPA project managers pursuant to Section 9.1 of the Elmendorf Air Force Base (EAFB) Federal Facilities Agreement (FFA). Marcia Combes will serve a lead remedial project manager (RPM) for Base wide activities, as well as Operable Units (OUs) 2, 3, 5, 6, 7. Michele Poirier-McNeill will serve as lead RPM for OUs 1 and 4. In addition both RPMs will serve as an alternative RPM on OUs for which they are not the lead. For communication and correspondence purposes, the lead RPM should be the point of contact, and the alternate should be copied. |
Jennifer Roberts |
| 4/9/1992 |
Update or Other Action |
EPA Memorandum April 9, 1992 Reply to the ATTN of ES-098. Subject Toxicity of Fuels. From Carol Sweeney, Toxicologist Health and Environmental Assessment Section. To Wayne Pierre Federal Facilities Superfuend Branch (HW-124). A response has been provided to the frequently-asked question of whether a reference dose or other toxicity information can be provided for fuel mixtures so that these mixtures can be addressed quantitatively in Superfund risk assessments. The memo from ECAO Cincinnati is attached (last attachment). They have developed reference doses for gasoline, JP-5/kerosene, and JP-4, and a cancer potency factor for gasoline. The memo emphasizes that these are provisional numbers and that considerable uncertainty is involved in this quantitative assessment, because of data limitations, and because inhalation studies were used to calculate oral reference doses.
I typed up a summary table showing the numbers (first attachment) and calculated some risk-based concentrations (second attachment). On the risk-based concentration table, I also
included ordnance compounds, because I hadn't made a table of those before that I can remember. The risk-based concentrations were calculated the same way as table II-1 and II-2 of the Region
10 Supplemental guidance; for soil, the same limitations apply, that the numbers presented do not consider pathways other than soil ingestion.
Toxicity Reference Vaules for Fuel Mixtures EPA Region 10 4/9/1992 Non-cancer effects-Gasoline (unleaded) RfD (mg/kg-day) Oral: 2.0E-1, Uncertainty Factor-Oral:1000, Level of Confidence-Oral: Low. Toxicity Data Source-Oral RfD: Memo 3/92. Carcinogenicity-Cancer Potency/(mg/kg/day): Oral 1.7E-3, Unit Risk (/ug/m3) 4.8E-7, Cancer Weight Of Evidence-C, Toxicity Data Source-Oral SF and Inhal. SF: Memo 3/1992.
Kerosene/JP-5 RfD2.0E-2, UF Oral: 10,000, LOC Oral: low, TDS Oral RfD: Memo 3/92
JP-4 RfD 8.0E-2, UF Oral: 10,000, LOC Oral: low, TDS Oral RfD: memo 3/92.
Screening Values for Water RBCs based on Ingestion, Residential
Gasoline-Risk = 10-6 (ug/L) 50, 10-4=5000 HI=1 (ug/L) 7000
JP-5 Kerosene Risk 10-6 10-4=NA HI = 1 (ug/L) 700
JP-4 Risk 10-6 10-4 = NA, HI = 1 (ug/L) = 3,000
Screening Values for Soils- RBCs Based on Soil Ingestion Residential
Gasoline-Risk = 10-6 (mg/kg) 400, 10-4 (mg/kg) 40,000, HQ = 1 (mg/kg) 50,000
JP-5 Kerosene Risk 10-6 10-4 NA, HQ =1 5,000
JP-4 Risk 10-6 10-4 NA, HQ = 20,000
USEPA Office of Research and Development, Environmental Criteria and Assessment Office Cincinnati, OH Subj: Oral Reference Doses and Oral Slope Factors for JP-4, JP-5; similar to Kerosene (CAS no. 8008-20-6), Diesel Fuel (CAS No. 68334-30-5), and Gasoline (CAS No. 8006-61-9) (AVGAS) [McChord AFB (Wash Rack/Treatment)/Tacoma, WA]. From Joan S. Dollarhide Associate Director, Superfund Health Risk Techncial Support Center, Chemical Mixtures Assessment Branch TO Carol Sweeney USEPA Region X.
This memorandum is in response to your request for oral systemic and carcinogenic toxicity values for JP-4, JP-5, diesel fuel, and gasoline (AVGAS) found to contaminate soil and
groundwater at McChord AFB (Wash Rack/Treatment), Tacoma, WA. We have attempted to derive RfDs and slope factors for the above fuel mixtures. We have derived provisional RfDs for
gasoline, JP-4, JP-5 and diesel fuel; provisional cancer weight-of-evidence classifications of C for gasoline and D for JP-4, JP- 5 and diesel fuel; and a provisional slope factor (adapted from an interim Agency value) for gasoline
Based on the available evidence, unleaded gasoline can be assigned to U.S. EPA (1986) weight-of-evidence Group C: possible human carcinogen. An earlier U.S. EPA document assigned unleaded
gasoline to Group B2 as a probable human carcinogen (u.s. EPA, 1987a), but that document predates the U.S. EPA (1991d) conclusion that the male rat kidney tumors produced by gasoline
are not predictive for humans, and therefore should not contribute to the weight-of-evidence or dose-response assessment of carcinogenicity. IARC concluded that marine diesel fuel is possibly carcinogenic to humans (Group 2B), but light diesel fuels and jet fuels are not classifiable as to their carcinogenicity in humans (Group 3). |
Jennifer Roberts |
| 7/31/1992 |
Update or Other Action |
1992 Limited Field Investigation: Field observations made during the drilling of these two borings indicate that some type of substance capable of being identified with a photoionization probe was present. Because these odors were detected at depths above the suspected discharge point of these onsite dry well locations, it is possible that some surface spills have occurred at this source. The field sampling team confirmed these observations when they noticed an obvious non-petroleum odor during drilling.
As a result of the geophysical survey & soil sampling conducted at SS18, the recommended action for the outfall structure source areas investigated at SS18 is No Further Action (NFA). The primary criterion used to place floor drains & associated outfalls into the NFA category at SS18 was whether the concentration of contaminants in any sample obtained during the LFI exceeded the risk-based criteria specified by the regulatory agencies. None of the soil samples collected during the LFI at SS18 contained analytes in excess of risk-based criteria.
The concentrations of pesticides detected during SS18 sampling are not expected to be mobile & act as an contaminant source. GW was not evaluated during the LFI. Any GW contamination present will be evaluated as part of the ongoing remedial investigation at Operable Unit (OU) 5. The criteria for NFA were met at each of the source sampling locations; therefore, NFA is justified for the building floor drains & outfalls at Source SS18.
NOTE TO FILE: "Limited Field Investigationa8 or "LFI" shall mean screening investigations of potential source areas with, inadequate data to determine whether these areas pose an unacceptable risk to human health or the environment. LFIs will be conducted at the old spill/disposal sites to identify whether or not these sites pose an unacceptable risk to public health from soil ingestion, dust inhalation, future agricultural use & crop uptake or direct contact. The potential for these areas to represent a significant source to GW contamination will also be evaluated. Prior to performing LFI's a workplan will be developed identifying the Data Quality Objectives established based on the conceptual site model development.
As the objectives of the LFI are to ascertain the potential risk to human health from shallow soil contamination &/or the risk to human health from GW contamination resulting from tle leaching of contaminants from these areas, the scope of the study is significantly less than that of an RI/FS. A SAP consisting of a FSP & QAPP will also be submitted as part of the workplan. At completion of the LFI investigation, a LFI report which contains the findings of the investigation shall be submitted to the agencies for review & comment.
A determination shall be made between the Project Managers to the disposition of each of the sources. Based on report results a decision will be reached between the Project Managers on what specific source areas in the OU require follow up action. The decision will be reflected in the administrative record." |
Louis Howard |
| 8/7/1992 |
Meeting or Teleconference Held |
CH2MHILL EAFB meeting minutes from a July 31, 1992 meeting to discuss the preliminary results of the OU5 soil gas survey field work and reach consensus among project managers on locations for placement of soil borings and groundwater monitoring wells for the next phase of the RI. Petroleum hydrocarbons generally have not been present in soil gas, potentially due to the weathering of the light end hydrocarbons. The majority of the results of the seep samples indicated petroleum hydrocarbons preliminary results indicate heavy end hydrocarbons. The results of the soil gas survey also indicated widespread low level halogenated solvent contamination.
ST37: Diesel fuel Line Leak-in general, results in area are similar to the Black and Veatch (B&V) study as far as the general perimeter of the source area, soil gas survey detected one hit just west of the source area perimeter, and no hit in area sampled east of source area perimeter.
New borings/well locations: install new soil boring/groundwater well below bluff just west of current source area perimeter; locate 2nd new soil boring/well below bluff area just north of railroad tracks and about midpoint in source area if existing well (SP1-01) in that area is not suitable for sampling; additional soil boring/well installed further east along access road just north of railroad tracks; 3 more soil borings/wells along south side of railroad tracks along area below the bluff and 4 soil borings along POL line on bluff. |
Jennifer Roberts |
| 1/25/1993 |
Update or Other Action |
Closure of State-Elmendor Environmental Restoration Agreement (SERA) Site LF-12, Johnson's Camp Landfill
1. A 1983 Installation Restoration Program (IRP) Phase I report for Elmendorf AFB reported the existence of an inactive construction and demolition refuse disposal site known as D-12,
(renamed LF-12) the Johnson's Camp Landfill. The identification and location of the landfill was based on anecdotal evidence such as interviews with unnamed base personnel. No visual evidence of contamination was found. The 1983 report indicated the site was used in the late 1940's and early 1950's, consisted of less than one acre in total area, and was closed and landscaped with local soils. A map of the site area is attached.
2. No evidence of waste disposal activities in the alleged area was found. A review of aerial photographs from the years 1950, 1962, 1972, and 1982 revealed no disturbance to topography ot
vegetation typical of landfill practices.
3. A boring was performed in 1988 to facilitate monitoring well installation for another source area. This boring, designated SP14-02, was placed in the purported location of LF-12 to a depth
of 45 feet. The attached boring log reveals no evidence of landfill activities in the boring location. Undisturbed sandy gravels typical to the developed portion of the base underlie the
alleged LF-12 area.
4. An additional boring was performed on the eastern edge on the site in 1992 under similar circumstances. This boring, known as OU5MW-07, also revealed no evidence of landfill activities.
5. Given the lack of evidence for any waste disposal in the alleged LF-12 area, Elmendorf AFB proposes this site be closed in accordance with the SERA. If evidence of waste disposal
activities in the LF-12 area is discovered your office will be notified and site investigation activities under SERA will be resumed. |
Jennifer Roberts |
| 4/1/1993 |
Update or Other Action |
Source SS18 (Building 22-021) is included in Operable Unit (OU) 4 for purposes of remedial investigation at Elmendorf AFB under the Comprehensive Environmental Response, Compensation and Liability Act (CERCLA). Ten maintenance facilities were grouped together in OU4 for a Limited Field Investigation (LFI) during 1992. These maintenance facilities were suspected of having floor drains that emptied into dry wells, leach fields, or storm drains. Past practices at these buildings may have released hazardous substances to the environment through the floor drains and outfall structures.
Source SS18 was originally identified as a potential source of contamination in the 1983 Phase 1 record search. It is located about 850 feet south of Second Street along the east side of Maple Avenue. Building 22-021, which rests on a concrete floor, houses the pest management operations of the base. There is an abandoned floor drain in the mixing room that has been plugged with concrete
The purpose of the 1992 LFI conducted at SS18 was to identify and evaluate the drain outfalls at Building 22-021, and to assess the possible environmental impacts that may have resulted from past operations and disposal practices. The field investigation focused on soil sampling at locations of dry wells or other outfall structures. Groundwater sampling was not performed during the LFI. The results of the LFI were used to determine the final disposition of the outfalls and to recommend either No Further Action (NFA), or that a remedial investigation/ feasibility study be conducted.
As a result of the geophysical survey and soil sampling conducted at SS18, the recommended action for the outfall structure source areas investigated at SS18 is No Further Action (NFA). The primary criterion used to place floor drains and associated outfalls into the No Further Action (NFA) category at SS18 was whether the concentration of contaminants in any sample obtained during the LFI exceeded the risk-based criteria specified by the regulatory agencies. None of the soil samples collected during the LFI at SS18 contained analytes in excess of risk based criteria. The concentrations of pesticides detected during SS18 sampling are not expected to be mobile and act as an contaminant source. Groundwater was not evaluated during the LFI.
Any groundwater contamination present will be evaluated as part of the ongoing remedial investigation at OU5. The criteria for NFA were met at each of the source sampling locations; therefore, NFA is justified for the building floor drains and outfalls at Source SS18.
The United States Air Force (Elmendorf Air Force Base), U.S. Environmental Protection Agency Region 10, and the Alaska Department of Environmental Conservation have completed a review of the information provided in the Final OU4 Limited Field Investigation Report for the source area located at Source SS18, Building 22-021, on Elmendorf Air Force Base. Based on this review, the above agencies have determined that No Further Action for purposes of investigation or study is justified for SS18. |
Jennifer Roberts |
| 4/15/1993 |
Update or Other Action |
Keven K. Kleweno (KKK) of ADEC received a fax from the Alaska Department of Fish and Game regarding the high nitrate levels in Ship Creek surface water. Letter was addressed to Colonel Tipp Simpson 11530 Q Street. ADF&G has been working with the Base Environmental office on the problem with the high nitrate levels in Ship Creek. ADF&G began investigating the problem in 1990 after nuisance weed began growing in the Base Power plant cooling pond (ADF&G is responsible for maintaining the water flow through the cooling pond). ADF&G's labor costs to remove the weeds from the power plant's cooling water intake screen is approximately 5,000 dollars annually. The nuisance weed is an indication of nitrate pollution. After a year of water tests, ADF&G found that most of the nitrates enter the creek through a bog at the end of the EAFB North-South runway. The level of nitrates in the water is as much as 30 times higher below the base runway as above and the total amount of nitrates entering the creek is over 100,000 pounds per year.
ADF&G believes the source of the nitrates is the urea and de-icing agents used on the runways. Snow plowed from the runway is deposited at the south end of the runway. The runoff from this snow pile may be entering a bog south of the runway and the bog eventually drains into Ship Creek. The high nitrate levels pose several problems:
1) The weeds, besides increasing labor costs to ADF&G, also increase the risk of loss of cooling water to the power plant.
2) The power plant has found their cooling tubes eroding faster than usual. This may be due to the higher nitrate levels.
3) Increased risk to fish health. Though the nitrate levels in the Creek water are not directly toxic to the fish, in the last four years we have seen greater organic loads. The increase in organics can eventually lead to greater parasite populations and to more fish health problems at the hatchery.
In the future, ADF&G would like the AF to deposit the runway snow to an area that does not drain into Ship Creek. |
Kevin Kleweno |
| 6/8/1993 |
Update or Other Action |
Staff sent the USAF a letter regarding the OU5 RI/FS report. The letter formalizes ADEC's request for a 20 day extension on comments for the draft OU5 RI/FS report. Reasons for the extension were discussed at the December 3, 1993 remedial project managers meeting and are related to the current scheduled overlap of the OU2 proposed plan (PP) and record of decision ROD) and OU5 PP and ROD. OU5 PP present due date 3/15/94 and the new due date 4/15/94. OU5 Final ROD due date 11/12/94 and new due date due 12/2/1994. 20 day extension will make comments for the OU5 RI/Fs draft report due on January 10, 1994. |
Jennifer Roberts |
| 1/11/1994 |
Document, Report, or Work plan Review - other |
Jennifer Roberts provided the Air Force (AF) with comments on the draft final Remedial Investigation/Draft Feasibility Study Report (RI/FS) for OU5 dated November 18, 1993. Additional evaluation of the remedial actions at the snow melt pond is requested. ADEC disagrees with the AF's proposed recommendation of no further action. The presence of PCBs are of ecological concern and ADEC would like the AF to consider the snow melt pond area as a passive constructed wetlands treatment system for the seeps in the western and central areas of OU5. If, during construction of the wetland treatment system, the PCBs as an ecological impact are addressed, then two objectives would be satisfied by one action (*note to file-this is the first time that the Wetlands remediation system idea has been raised by ADEC).
The property boundary of the snow melt pond is located on property owned or managed by the Alaska Railroad (ARR). As discussed in our meeting on 1/10/1994, actions that take place on or may impact the property held by ARR must be coordinated with the ARR and undertaken with their permission. ADEC is in the process of contacting the ARR to discuss the need for PCB sampling of the railroad bed adjacent to the snow melt pond. ADEC raises this issue to insure that any remedial action contingent on access and coordination with ARR is being addressed early in the remedial planning stages. Sheen is present from the pond at the base of the bluff and the text should reflect that the sheen is a violation of Alaska water quality standards.
ADEC agrees with the statement that as long as the Base maintains control over land use and that contamination does not migrate off Base, deed restrictions are a viable option to evaluate for groundwater contamination. It is ADEC's experience that deed restrictions are not effective when property is held by the private sector, since there is no mechanism in state law that supports deed restrictions for contaminated property. For that reason, ADEC does not agree with the U.S. EPA's comments. ADEC does agree with EPA's comments regarding application of MCLs. In addition, state regulations consider all groundwater as drinking water and, therefore, MCLs (or in limited special cases, water quality standards) apply to groundwater.
In closing, after completing its review of the RI/FS for OU5, ADEC would like to make the observation that the previous agreement between EPA, DEC, and EAFB regarding the treatment of base wide groundwater contamination at OU5 should be reviewed and renegotiated between all 3 agencies. From the information presented by the OU5 RI/FS, it is clear that the contamination source areas at OU5 have, for a number of reasons, been undergoing natural mitigation. The report also indicates that passive wetlands treatment systems will address the contaminated seeps. In addition, the Base compliance monitoring of Ship Creek will insure that there is no degradation of natural water quality at Ship Creek from extremely low levels of contamination in groundwater that may be discharging directly into it. With this information it is clear that developing an extensive and costly treatment system for groundwater at OU5 to address other operable units or two party agreement (SERA) sites' groundwater contamination may not be the best or most effective policy. Therefore, EPA, ADEC and EAFB should, with the new information provided, reexamine and renegotiate the current base wide groundwater agreement. |
Jennifer Roberts |
| 1/12/1994 |
Update or Other Action |
NOTE: Federal Facility Agreement Section 10.2 addresses property that is not owned by the Air Force and access-To the extent that this Agreement requires access to property not owned and controlled by USAF, USAF shall exercise its authorities to obtain access pursuant to Section 104(e) of CERCLA, 42 U.S.C. 9604(e), and will make every reasonable effort to obtain signed access agreements for itself, its contractors, agents, U.S. EPA, and ADEC, and provide U.S. EPA and ADEC with copies of such agreements.
With respect to non-USAF property upon monitoring wells, pumping wells, treatment facilities, or other response actions are to be located, the access agreements should provide no conveyance of title, easement, or other interest in the property shall be consummated without provisions for the continued operation of such wells, treatment facilities, or other response actions on the property.
The access agreements should also provide to the extent practicable that the owners of any property where monitoring wells, pumping wells, treatment facilities, or other response actions are located shall notify the USAF, ADEC, and the U.S. EPA by certified mail, at least thirty (30) days prior to any conveyance, or the property owner's intent to convey any interest in the property and of the provisions made for the continued operation of the monitoring wells, treatment facilities, or other response actions installed pursuant to this Agreement. |
Louis Howard |
| 3/4/1994 |
Update or Other Action |
PCBs (Aroclor 1260) were detected in the near-shore sediment of the snowmelt pond above criteria for sediment level of concern. Interim remediation goal for PCBs is 1,900 ug/kg (if TOC equals 10%) 190 ug/KG (if TOC equals 1%) in soil (which includes sediments). Source is PCB SQCs and EPA recommends that SQCs be considered in establishing remediation goals for sediments. The goal is proportional to the TOC concentration as indicated.
However, the presence of chironomids at the water/sediment interface suggests that the contaminant in this near-shore is not biologically available, or that the taxa present are highly resistant to the contaminant (PCBs). Fish and invertebrates in Ship Creek do not appear to be at significant risk from OU5 contaminants. Plant stress, and possibly the reduced egg-hatching success in semi aquatic birds that nested near several surface water bodies, provided evidence of impaired ecosystem health. Causes of the plant stress could not be identified definitively, but they appear to be something other than fuel hydrocarbons. The most likely cause seemed to be mineral imbalances related to elevated manganese, and potentially cobalt, phosphorus, and pH in areas where plants showed signs of stress. The number of bird nests was not adequate to determine causes of nesting failure.
The risk characterization indicated that the most likely impacts of contaminants on terrestrial ecological receptors in OU5 would be most likely caused by: Inhalation exposure of small mammals to fuel hydrocarbon vapors when the animals were in their burrows. Dermal contact/absorption of fuel hydrocarbons by semi aquatic mammals, birds, and wood frogs in the golf course beaver pond (or elsewhere when surface sheens are present).
Metabolic uptake/inhibition effects of inorganics by plants near seeps and wetlands where plants exhibited signs of stress. Federal ambient water quality criteria and Alaska water quality standards or fuel hydrocarbons are being exceeded in the lower bluff pond and golf course beaver pond.
|
John Halverson |
| 3/4/1994 |
Risk Assessment Report Approved |
Risk assessment as part of the final RI/FS was received and approved. Concentrations of TCE 5.2 ug/L to 33 ug/L were detected in groundwater samples from MW01, MW02, and SP1-02 on the bluff in the Western Area of OU 5.
The upper aquifer groundwater pathway generated noncancer hazard index values exceeding 1.0 and total excess lifetime cancer risks equal to 1 x 10-4. The groundwater pathway assumed future residential exposures through ingestion, inhalation of vapors, and dermal contact with upper aquifer groundwater over a lifetime.
Total metals (arsenic and manganese) are the largest contributors to the groundwater risk estimates. Exposure by ingestion of the groundwater yields the highest risk values. Under reasonable maximum exposure (RME) assumptions, organic contaminants contribute between 10-5 and 10-6 excess lifetime cancer risks for future residents through ingestion of groundwater through showering. That level of risk occurs as a result of organic contaminants in all OU5 subareas. The organic contaminants contributing to the estimated risks include gasoline- and diesel-range organics, benzene and TCE. A future residential scenario for the upper aquifer groundwater at OU5 is highly conservative.
The upper aquifer at OU5 is unlikely to be used for domestic purposes because of low yield and availability of other piped water supplies. The aquifer is not currently being used at OU5. The major contributors to risk are polycyclic aromatic hydrocarbons (PAHs) and arsenic in surface soil. PAHs cumulatively result in a cancer risk greater than 1 x 10 -5. However, the PAHs occur in surface soils on the bluff face where a residence could not be constructed. Therefore, the scenario of the ingestion of soil by a residential receptor at SB29 is conservative and the potential for exposure is limited. SB29 is an area and a seep that forms a puddle.
The area measures only approximately 50 ft. by 50 ft. Because of the small size of the affected area, the improbability of any residential exposure, and the single compound nature of the impact, the FS will not focus on the PAH surface soil impacts. If any remedial action is deemed necessary clearly limited excavation and disposal of the affected soil would be the most effective solution.
Ecological risk: most likely impacts of contaminants on aquatic receptors in OU5 would be caused by dermal contact, absorption, or ingestion of fuel hydrocarbons, BTEX and PAHs by benthic macroinvertebrates in the golf course, beaver pond, wetland pond, and lower bluff pond. Impacts to aquatic bed plants in the golf course beaver pond and wetland pond hydrophyts by metabolic uptake of contaminants may also be a limiting factor to aquatic vegetation viability. |
John Halverson |
| 3/4/1994 |
CERCLA RI Report Approved |
Final version of the RI/FS received & approved. Source area ST37 is within Western OU5. The greatest gasoline range organics of 168 mg/kg & diesel range organics 1,160 mg/kg were detected at 10 to 12’ bgs in SB29. The deepest fuel hydrocarbon contaminated samples were collected from the saturated zone in SB18 indicating that the contaminants either migrated to GW at this location or at a location north, in the upgradient direction of GW flow.
Downgradient of the Elmendorf AFB power plant & between ST37 & ST38, OU 5 bluff runoff & numerous seeps collect in wetland ponds between the base of the bluff & the ARRC tracks. The dye-tracer study indicated that the runoff discharges to Ship Creek from a culvert at the end of Yakutat Street. At the western boundary of OU 5, a storm-water interceptor was observed collecting the runoff from the OU 5 bluff below Source ST37 & other numerous seeps. A dye-tracer study was conducted to locate the ultimate discharge point of the runoff.
Surface water & sediments: JP-4 at 0.8 mg/L (800 ug/L) & gasoline at 0.3 mg/L (300 ug/L), BTEX at 0.27 mg/L (270 ug/L) & 1,1-dichloroethane at 0.002 mg/L (2 ug/L) were detected in water sample SW08 from a puddle that is fed by GW seeps on the face of the bluff. Contaminants may have reached the puddle through the vadose zone soil, surface water runoff or GW seepage. Water sample SW09 from a ditch, downslope from the puddle, had a detectable concentration of 1,1,1-trichloroethane (0.0018 mg/L or 1.8 ug/L), a VOC not detected in the puddle or in GW within Western OU5; its source is unknown.
TCE at 5.2 to 33 ug/L were detected in GW samples collected from MW01, MW02, & SP1-02 on the bluff. In wells SP1-01, MW15, & MW16A on & below the bluff face had fuel hydrocarbons, benzene, toluene, xylenes & naphthalene detected. Contaminated soil zones lying above the water table probably represent a "smear zone" of contamination resulting from fuel that migrated to a higher water table & were left in the vadose zone or capillary fringe as the water table receded. The smearing of hydrocarbons may occur between seasons as the water table rises & falls. Hydrocarbons have migrated to surface soil along the bluff face via seep discharges.
The major contributors to the risk are PAHs & arsenic. Even if arsenic is excluded from the cancer risk for surface soils at SB29, PAHs cumulatively result in a cancer risk greater than 1 x 10-5. However, the PAHs occur in surface soils on the bluff face where a residence could not be constructed. Therefore, the scenario of the ingestion of soil by a residential receptor at SB29 is conservative, & the potential for exposure would be limited.
SB29 is an area near a seep that forms a puddle. The area measures only approximately 50’ by 50’. Because of the small size of the affected area, the improbability of any residential exposure, & the single compound nature of the impact, the FS will not focus on the PAH surface soil impacts. If any remedial action is deemed necessary, clearly limited excavation & disposal of the affected soil would be the most effective action. Based on the conclusions, the FS in Western OU 5 should focus on impacts to subsurface soil, seeps, & GW. |
John Halverson |
| 6/6/1994 |
CERCLA Proposed Plan |
Proposed Plan (PP) lists soil gasoline and diesel fuel contaminated within the western area of OU5 (near ST37). Gasoline 168 mg/kg max. concentration, cleanup standard 100 mg/kg ACM
Diesel 1,160 mg/kg max. concentration cleanup standards 200 mg/kg ACM.
Groundwater (GW) is listed as being contaminated with TCE, fuel, benzene in the western plume.
TCE max. concentration 33 ug/L cleanup standard 5 ug/L (FDW), Fuel constituents max. concentration 990 ug/L cleanup standard 10 ug/L (ASWQ), benzene max. concentration 8.5 ug/L cleanup standard 5 ug/L (FDW). The preferred alternative chosen is Natural attenuation (NA).
Human health risks Western area: 4.7 x 10-5 excess cancer risks from PAHs in soil. Groundwater: 1 x 10-4 excess cancer risks, HI = 3. Chemicals driving risk: Gasoline, diesel fuel and benzene.
The preferred alternative: Natural Attenuation with Institutional Controls for Groundwater and Beaver Pond Wetlands/Passive Extraction with a Constructed Wetland for Seeps/Isolation of
Snowmelt Pond Sediments/Excavation, Biopiling, andBackfilling for Soil.
It will effectively reduce risk to human health and the environment by actively treating contaminants most likely to come in contact with people, plants, and animals. It will prevent contaminated water from reaching Ship Creek, ensure that the contaminated upper aquifer is not used as a water supply while natural processes remediate (clean) the water, and clean up contaminated surface water, seeps, and soil to which plants and animals are exposed. At Snowmelt Pond, it will also remove surface sheens and prevent aquatic life from being
exposed to contaminated sediment.
Implementation of the preferred alternative is the least damaging to the environment. Fish and other aquatic life, plants, and land animals are protected and their habitats are preserved. The elements of the preferred alternative achieve these objectives at a reasonable cost. A constructed wetland for seeps is included because it could effectively treat the seep water at a low cost and it serves a dual purpose of treating sheens on the Snowmelt Pond and isolates contaminated sediment.
Biopiling is included because it could remediate the contaminated soil quickly, and at a reasonable cost, and is easily combined with the installation of passive seep water extraction wells. Finally, natural attenuation with institutional controls for groundwater would provide adequate exposure protection without the technical problems associated with active groundwater treatment alternatives.
The preferred alternative was also selected keeping in mind that the assumptions behind the human health risk calculations are very conservative. It is extremely unlikely that future residents would use contaminated water from the upper aquifer for drinking and showering. None ofthe upper aquifer wells are being used for any purpose and none are expected to be used in the future. Furthermore, it is highly unlikely that residences would be constructed along the bluff since it is an industrial area. This reinforces the selection of natural attenuation with institutional controls for groundwater. |
Jennifer Roberts |
| 7/1/1994 |
Update or Other Action |
Alaska Railroad Corporation (Alaska Railroad) sent Ralph Scott Public Affairs Office 3WG/PA a letter regarding EAFB OU5 Proposed Plan for Remedial Action. First issue: USAF has built certain facilities on property owned by the Alaska Railroad. These facilities include a pump station and a road. These acts constitute trespassing and may constitute a taking of the property by inverse condemnation. The first step in resolving this issue is to get a precise description of what the Alaska Railroad property the AF now occupies. Alaska Railroad requests the AF provide an "as-built" diagram, prepared by a licensed surveyor, of the facilities located on Alaska Railroad property.
Second issue: the proposed remedy for the contamination in the snowmelt pond is to place a cap on the pond. What concerns the Alaska Railroad is the fact the AF proposes to render the Alaska Railroad realty permanently unusable and not compensate them for doing so. Alaska Railroad considers it appropriate that under the circumstances of the case, the AF enter into a long term lease with the Alaska Railroad for the snow melt pond. |
Jennifer Roberts |
| 8/1/1994 |
Update or Other Action |
No Further Action Document for Sources ST38 & SS42. ST38 is the area where a fuel line leak occurred during 1964 & 1965. An unknown quantity of JP-4 jet fuel seeped out of the bank southeast of Bldg. 22-010 near a drainage ditch crossing Post Road. No fuel was recovered at this location. ST38 was combined with SS42. Source SS42 is next to Bldg. 22-013. An estimated 8,000 gallon one-time spill of diesel fuel occurred on March 31, 1976. The spill occurred when the overflow valve failed during transfer of fuel from an aboveground tank to an underground tank. Most of the fuel was reportedly recovered from the frozen ground.
The purpose of the document is to explain the rationale for no further action (NFA) to be taken regarding the soils/*vadose zone at ST38 & SS42. Ten soil borings were drilled at Sources ST38 & SS42 during a 1988 remedial investigation/feasibility study [RI/FS) by Black & Veatch. Five of these borings were converted to monitoring wells (SP2/6-01 through SP2/6-05). Evidence of contamination, indicated by portable photoionization analyzer HNu) readings, odor, & visual inspection of samples, was recorded during drilling. Soil samples from the borings were analyzed for TPH, halogenated volatile organic compounds (VOCs), semivolatile organic compounds, & soil moisture content.
Soil contamination appeared til be located in a zone at the top of the water table. Contaminants detected in the soil at boring SP2/6-10 included 2-methylnaphthalene at 17 mg/kg & TPH at 9,843 mg/kg at a depth of 30 to 31.5 feet. Groundwater in boring SP2/6-10 was encountered at 30.2 feet. Total petroleum hydrocarbons were also detected in boring SP2/6-04 at 1,763 mg/kg at a depth of 35 to 36.5 feet Groundwater in boring SP2/6-04 was encountered at 33.5 feet. A review of boring logs shows positive HNu readings in eight of the borings with the maximum readings at depths of 30 to 40 feet (Black & Veatch 1990).
Monitoring well samples collected by Black & Veatch confirmed groundwater contamination. TPH was detected in groundwater in four of the seven monitoring wells at Sources ST38 & SS42. ranging from 1.0 microgram per liter ug/l to 64 ug/L at GW-6A. Ethylbenzene, toluene. & xylenes were also detected in GW-6A at concentrations of 30 ug/L. 4.5 ug/L. & 25 ug/L. respectively.
Petroleum hydrocarbons were detected at ST38 & SS42 in only 3 samples taken from the saturated soil layer, which indicates residual contamination of the saturated soil & groundwater beneath the source areas. Petroleum hydrocarbons were detected in soil only at the water table in borings SP2/6-04 & SP2/6-10, which is indicative of saturated soil with groundwater contamination. This contamination WILL be addressed by the OU5 feasibility study during 1993.
The Federal Facility Agreement (FFA) initiated a remedial investigation (RI) of source areas ST38 & SS42 within Operable Unit (OU) 5 at Elmendorf Air Force Base (EAFB). The U.S. Air Force (EAFB), U.S. Environmental Protection Agency (EPA), & the Alaska Dept. of Environmental Conservation (ADEC), have completed a review of the information provided in the OU 5 RI Report for the vadose zone soils at Sources ST38 & SS42.
Based on this review, the above agencies have determined that No Further Action (NFA) for purposes of investigation or study is justified for the VADOSE ZONE SOILS at this source area. Groundwater & saturated soil contamination beneath & downgradient of Source SS53 were evaluated as part of the feasibility study for OU 5 & is not attributed to SS42. Signed by Patrick Coullahan Lt. Col USAF Base Civil Engineer, Marcia Combes EPA project manager, Jennifer Roberts ADEC project manager on August 4, 1994.
NOTE to file: RI/FS states for ST38 & SS42- No further action for the soil, surface water, & sediment pathways are warranted for the following reasons: Total Fuel Hydrocarbons (TFH) diesel, JP-4, & BTEX compounds were only detected in soil at depths of 10 to 60 feet below ground surface (SB23, MW11, SP2/6-10, & SP2/6-04) & are not in a surface soil pathway accessible by residents or terrestrial animals.
Detected contaminant concentrations pose less than 1 x 10 -4 cancer risk & have a hazard index (HI) less than 1 for non-cancer risks; Contaminant of concern (COC) concentrations do not exceed ARAR or TBC levels; &; There are no identifiable affects of contaminants on aquatic biota or terrestrial plants or animals. |
Jennifer Roberts |
| 8/4/1994 |
Update or Other Action |
SD40 Railroad Maintenance Area, Oil Spill August 4, 1994 No Further Response Actions Decision Document Signed.
Petroleum hydrocarbons, however, were detected in the saturated soil layer, which indicates residual contamination of the saturated soil, sediments, and groundwater beneath the source areas. Groundwater contamination has also been detected in upgradient wells, indicating that there is an upgradient source. This contamination will be addressed by the OU 5 remedial investigation/feasibility study during 1993.
Decision documents NFRA (no further response actions)
Site ID Source name, date written, Date signed
SS18 Building 22-021 1 April 1993 7 May 1993
SD26 Hangar 14/Building 43-550 1 April 1993 7 May 1993
SD27 Building 42-300/Hangar 8 1 April 1993 7 May 1993
SD30 Building 21-900 1 April 1993 7 May 1993
ST38 JP-4 Fuel Line Leak, Bldg. 22-010 24 June 1994 4 August 1994
SD40 Railroad Maintenance Area Oil Spill 24 June 1994 4 August 1994
SS42 Diesel Fuel Spill, Bldg. 22-013 24 June 1994 4 August 1994
ST46 JP-4 Fuel Line Leak 24 June 1994 4 August 1994
SD52 Cherry Hill Ditch 20 August 1993 20 August 1993
SS53 Golf Course Seep 24 June 1994 4 August 1994
SS63 Classic Owl, Bldg. 52-140 8 September 1994 27 September 1994
SS22 DRMO Storage Facility 25 September 1991 November 1991 (FFA) (REOPENED)
RW17 Radioactive Waste Site 25 September 1991 November 1991 (FFA) |
Jennifer Roberts |
| 8/15/1994 |
Update or Other Action |
Letter sent to Ms. Cindy Gilder Manager Environmental Services Alaska Railroad Corporation (Alaska Railroad). ADEC, EPA, AF, working on contamination investigations under CERCLA. During the remedial investigation, sediments were sampled in several water bodies in OU5. Results show that the sediments are contaminated with low levels of polychlorinated biphenyls (PCBs). Efforts made to determine the potential source of PCBs on EAFB were inconclusive. The remedial strategy developed by AF, ADEC, EPA includes developing the Snowmelt pond as a wetland treatment area, which will, in essence, cap or break the ecological exposure pathway to the PCBs and treat the contaminated groundwater through natural processes.
ADEC is concerned that the source of the PCBs has not been determined. Review of the data indicates that a potential source area may be the Alaska Railroad spur roadbed or possibly the main track roadbed. Therefore,
ADEC requests the Alaska Railroad sample these areas to determine if they are the source area for the PCBs. Alaska regulatory code 18 AAC 75.327 (a) states that: "...immediately upon becoming aware of a discharge of a hazardous substance to land or waters of the state, any person responsible for that discharge shall contain, cleanup, and dispose of the material collected, using methods for which approval has been given by ADEC. ADEC requests that the Alaska Railroad proceed promptly, in accordance with regulations, with an environmental investigation to determine if the PCBs in the Snow melt pond are from a source area on Alaska Railroad property. ADEC requests the Alaska Railroad develop a work plan for PCB sampling of this area and submit the work plan to ADEC for review and approval by September 1, 1994. The work plan should contain:
1) Field sampling protocols and location of samples. The purpose of this sampling effort is a focused screening for PCBs, therefore information on past Alaska Railroad maintenance practices should be evaluated to assist with determining sample locations.
2) Quality assurance/quality control measures both field work and laboratory analysis must be included. The lab QA/QC must indicate the detection limits, laboratory protocols.
3) The work plan should include a timeline for sampling, lab analysis, and reporting results to ADEC. |
Bill Lamoreaux |
| 8/24/1994 |
Update or Other Action |
Alaska Railroad sent a letter and plan for the snowmelt pond two weeks ahead of schedule. During a site reconnaissance on August 3, 1994, photos were taken of the pond and surrounding areas, and some of these were included in the sampling plan. It appears the drainage from the bluff has increased the size of the pond beyond the limits of natural containment. The result is the formation of ponds and wetlands in the topographical depression between the rail spur and the main tracks to the south. Therefore, the possibility of PCB migration from the tracks upgradient to the pond is remote. |
Bill Lamoreaux |
| 9/20/1994 |
Document, Report, or Work plan Review - other |
Letter to Alaska Railroad regarding the snowmelt pond sampling plan submitted on August 24, 1994. The document does not provide enough sampling to adequately characterize the site. ADEC has enclosed an alternative sampling plan based on guidance from EPA "Field Manual for Grid Sampling of PCB Spill Sites to Verify Cleanup." This guidance document recommends taking 37 samples for an area of contamination where the radius of the sampling area exceeds 11 feet. The sampling radius at the snowmelt pond was found to be 375 feet.
This revised proposed sampling plan using EPA guidance is conservative. However, in view of the previous analysis, ADEC feels the objectives may be met by taking only twelve samples as indicated on the attachment. This additional sampling will be beneficial in identifying the source of the contamination. |
Jennifer Roberts |
| 11/17/1994 |
Document, Report, or Work plan Review - other |
Jennifer Roberts provided comments to the AF on the draft final OU5 Record of Decision (ROD). Additional detailed comments were verbally provided to the AF during a conference call between EPA, AF, and ADEC project managers on November 17, 1994. Reference to intrinsic remediation should be changed to read "natural attenuation" to be consistent with the OU5 Proposed Plan. Decide whether the term "cleanup goals" vs. "cleanup standards" should be consistently used in the document. Due to contamination left in place at OU5, it will be necessary to have the standard 5 year review.
Please add the reference in the Statutory Determinations section and Section 5.0 the Selected Remedy. Chemical Specific ARARs: The maximum contaminant concentration levels (MCLs) established for drinking water by 18 AAC 80.070 (drinking water) are applicable to groundwater as a chemical specific regulation. Waters discharged from the constructed wetland at the Snowmelt pond are considered a nondomestic wastewater since they have undergone treatment prior to discharge.
Therefore this discharge is subject to the chemical specific discharge levels in Alaska nondomestic wastewater regulations, 18 AAC 72.500 and the water quality criteria listed in 18 AAC 70 (Water Quality Standards) as it applies to nondomestic wastewater discharges. For petroleum contaminated soil that will be removed and remediated, it is appropriate and relevant to apply the NON-UST Contaminated Soil Cleanup Levels guidance under 18 AAC 75 Oil Pollution Prevention Requirements. Use of this guidance is consistent with ADEC policy for petroleum contaminated soil at EAFB from both UST and NON-UST sources and, therefore, it is consistent to apply this guidance to OU5 soils.
Location Specific ARARs: Due to the work in the snowmelt pond (dredging and filling), it is possible that the Corps 404 Wetlands Policy may apply. This issue should be researched to see if the 404 Wetlands is an ARAR. Action specific ARARs: It is appropriate to apply Alaska Wastewater regulations (18 AAC 72) for the water treated by the constructed wetland at the Snowmelt pond. Due to the treatment of the water, it would be considered a nondomestic wastewater discharge and therefore subject to the substantive requirements of 18 AAC 72.500-72.600 and 18 AAC 70 Water Quality Standards, as it applies to nondomestic wastewater discharge. |
Jennifer Roberts |
| 1/19/1995 |
Update or Other Action |
OU5 Groundwater Modeling Report received. The objectives of the modeling task were to: Evaluate the movement of contaminants across Elmendorf AFB and within Operable Unit (OU) 5; Predict contaminant migration over the next 30 years; and Determine if selected receptor points along Ship Creek and an unnamed beaver pond will be impacted by contamination. A 3 dimensional finite element model (SALT) developed at the University of Waterloo was selected because of its versatility in handling complex geology and boundary conditions. Radian Corporation modified the model to improve the program's efficiency and to include contaminant decay and site specific boundary conditions along Ship Creek. This modified version called SALT 3, consists of groundwater flow and contaminant transport models. The hydrogeology of the modeled area was evaluated using lithologic data collected from all available boreholes within the modeled area and water level data collected from shallow water table monitoring wells in March and September 1993.
After a review of the groundwater quality data from September 1993 groundwater sampling and available OU 1, 2, and SERA site data, benzene and trichloroethene were selected as representative compounds for this modeling effort. Benzene and TCE were selected due to their potential health impacts. As metals and semivolatile compounds were only sporadically detected at concentrations near maximum contaminant levels (MCLs) they are not constituents of environmental concern in much of the aquifer beneath EAFB and were not modeled.
Concentrations in the recharge over the water table was set to zero except for at source areas. Since improvement in soil quality is expected over time, the sources were assumed to cease contributing benzene and TCE to groundwater afar five years. All concentrations in the recharge zone were therefore set to zero at the end of the first five years.
The conclusions of the base case simulations show that benzene and TCE will migrate toward the south. However, the concentrations of these contaminants will decline over time. Because of infiltration, there may be some localized areas that experience a temporary increase in concentration as a "pulse" migrates toward the south. Benzene will be detectable in groundwater for over 20 years, however, the concentrations in groundwater base wide should be below the MCL after 15 years (1993-2008). TCE concentrations will be detectable in groundwater after 30 years (2023) and should be less than the MCL base wide after 20 years (2013).
Benzene and TCE will spread and migrate toward the south from identified source areas. Concentrations in groundwater flowing toward Ship Creek and the unnamed beaver pond should not exceed 1 ug/L over the period modeled. The model predicts that the concentrations of these compounds in groundwater near surface water bodies will be approximately 1 ug/L after 5 years (1998) and will then steadily decline over time. The results of the groundwater modeling effort indicate that the groundwater can be remediated naturally (MNA) in all OUs without any predicted increase impact to sensitive receptors in OU5. The model predicted, that in five years, benzene and TCE concentrations in OU5 from upgradient sources will be above 1 ug/L but less than 10 ug/L. In 10 years (2003), the concentration of these compounds is predicted to be less than 1 ug/L in OU5, indicating a measurable improvement in water quality over time. |
Jennifer Roberts |
| 2/1/1995 |
Cleanup Level(s) Approved |
Level C criteria applies for the soils: 500 mg/kg GRO, 1000 mg/kg DRO, 2000 mg/kg RRO, 0.5 mg/kg benzene, and 50 mg/kg total BTEX. Groundwater cleanup levels: TCE 5 ug/L, benzene 5 ug/L, TFH Diesel 10 ug/L, TFH Gas 10 ug/L. Surface water: no sheen, TFH Gas 10 ug/L and JP-4 10 ug/L.
GW monitoring will be discontinued if contaminant levels are below cleanup levels during two consecutive monitoring events. In that case, no further action for GW will be required. During the final round of monitoring, samples will be collected & analyzed for ALL constituents that exceeded MCLs during the [remedial] investigation (e.g. OU3, OU5) including [but not limited to] VOCs, SVOCs, & metals. These results will be evaluated before a final determination is made that GW meets all cleanup requirements. |
Jennifer Roberts |
| 2/1/1995 |
CERCLA ROD Approved |
The ROD lists the major components of the selected remedy as: Contaminated seep water in the western & middle portions of OU5 to be passively drained using horizontally inserted extraction wells in the bluff. The water will flow to a constructed wetland, currently built in the snowmelt pond. A layer of material (gravel) will be placed over the sediments which contain PCBs in order to isolate the contamination. Approximately 3000 cubic yards of soil contaminated with fuel products will be excavated & treated at an on base treatment facility to reduce contaminant levels below cleanup goals. The treated soil will be reused on base either to fill the excavation or for general fill.
Natural attenuation (NA) will be relied upon to attain cleanup levels in the contaminated upper aquifer & surface water other than seep water, including the beaver pond wetland area. Institutional controls (ICs) that prohibit use of the upper aquifer will ensure that people will not be exposed to contaminated GW until cleanup goals are achieved. GW, seep water & SW will initially be sampled on a quarterly basis. Sediment will be sampled annually.
Results of the monitoring program will be assessed annually for at least five years to determine if cleanup levels have been achieved. If cleanup levels have not been reached, aggressive actions such as air sparging with soil vapor extraction or active extraction with air stripping may be necessary. Bioventing of soil is an additional option that could be used to treat soil contamination.
If there are any significant differences between the actions being taken as apart of this ROD, an explanation of significant differences or a ROD amendment will be issued. While it is not known exactly when the time to achieve MCLs in the GW, it could be as short as 10 to 15 years based on the GW modeling done. The remedy is appropriate because fuel pipes are regularly maintained & pipelines & tanks are hydrostatically tested annually & pressure tested under higher pressures triennially. Monitoring data will be regularly reviewed to assess the progress made by the selected remedy toward the cleanup goals. If problems are identified, further remedial action will be considered.
NOTE TO FILE: § 300.430 Remedial investigation/feasibility study & selection of remedy.(a) General—(1) Introduction. The purpose of the remedy selection process is to implement remedies that eliminate, reduce, or control risks to human health & the environment. Remedial actions are to be implemented as soon as site data & information make it possible to do so.
Accordingly, EPA has established the following program goal, expectations, & program management principles to assist in the identification & implementation of appropriate remedial actions.
(iii) Expectations. EPA generally shall consider the following expectations in developing appropriate remedial alternatives:
(D) EPA expects to use institutional controls such as water use & deed restrictions to supplement engineering controls as appropriate for short- & long-term management to prevent or limit exposure to hazardous substances, pollutants, or contaminants. Institutional controls may be used during the conduct of the remedial investigation/feasibility study (RI/FS) & implementation of the remedial action &, where necessary, as a component of the completed remedy.
The use of institutional controls shall not substitute for active response measures (e.g., treatment &/or containment of source material, restoration of ground waters to their beneficial* uses) as the sole remedy unless such active measures are determined not to be practicable, based on the balancing of trade-offs among alternatives that is conducted during the selection of remedy.
“EPA expects to return usable ground waters to their beneficial uses wherever practicable, within a time frame that is reasonable given the particular circumstances of the site. When restoration of ground water to beneficial uses is not practicable, EPA expects to prevent further migration of the plume, prevent exposure to the contaminated ground water, & evaluate further risk reduction” 40 CFR 300.430(a)(1)(iii)(F). |
Jennifer Roberts |
| 2/1/1995 |
Institutional Control Record Established |
ICs established by signing of ROD and subsequently been enforced by land planning department at the Base and environmental restoration staff oversight. Land use and water use restrictions are in place to prevent access to contaminated media throughout OU5 until cleanup levels have been achieved. The contaminated source areas at OU5 and applicable groundwater use restrictions are documented in the Base General Plan, which is consulted prior to approval of changes in land use , siting, work orders, and/or drilling permits. Installation of wells in the contaminated plume for residential, industrial and agricultural use will be prohibited by the Base General Plan until cleanup levels have been achieved. Water use restrictions exist in the form of a Base wide prohibition on use of the shallow groundwater aquifer due to contamination by order of the Wing Commander. |
Jennifer Roberts |
| 3/8/1995 |
Document, Report, or Work plan Review - other |
Operable Unit 3 Remedial Investigation/Feasibility Study approved contingent upon [groundwater] being monitored as part of OU 5 [groundwater] monitoring. WEST INTERSOURCE AREA: Isolated contaminants were detected in the shallow aquifer in groundwater wells at OU 3. The contamination was found in several wells but at low concentrations and no groundwater plumes could be identified at the OU 3 source areas. OU3 EAST: Benzene, trichloroethene (TeE), dichloroethene (DCE), and tetrachloroethene (PCE) were detected in the shallow aquifer in wells in the au 3 east groundwater area.
Sources for these compounds could include the former earthen disposal trenches, heavy equipment storage and maintenance activities, and leaks or spills in the vicinity of underground storage tanks at SD 16. OU3 WEST: Several VOCs were detected in shallow-aquifer groundwater samples including chloroform, chloromethane, 1,1,1-trichloroethane, trichloroethene, and trichlorofluoromethane, Isolated occurrences of bis(2-ethylhexyl)phthalate were observed intermittently in samples, Cadmium and vanadium were the only inorganic copes detected in the shallow-aquifer groundwater samples.
Groundwater monitoring data will be collected from monitoring wells at OU 3 to ensure that groundwater from OU 3 will not impact the sensitve receptors at OU 5. The risks for groundwater, based on both organic and inorganic concentrations, are acceptable. No current receptors exist for groundwater at the base due to institutional controls. The only potential
receptor of groundwater is at OU 5 and this is addressed in the OU 5 ROD.
The Basewide groundwater monitoring plan describes the monitoring locations, sampling frequency, analytical parameters, and reporting format. Since potential future impacts will be monitored (as part of OU 5 long-term monitoring), no further action is planned for this site (08-Mar-1995 OU 3 RIFS Report 7.6.5 Conclusions). |
John Halverson |
| 4/10/1995 |
Update or Other Action |
Ray Burger sent letter to AF regarding the Time Extension on OU5 Remedial Action. Since a formal agreement on acquiring necessary access to the property is still pending, dispute Air Force diligence, ADEC agrees that good cause for this extension exists pursuant to Section 26.1 (Force Majeure) of the FFA. |
Ray Burger |
| 5/22/1995 |
Update or Other Action |
USAF letter to Alaska Railroad Robert Hatfield President/CEO regarding the extent of groundwater contamination at OU5. The AF, EPA and ADEC are presently working on a cleanup design for OU5. The AF would like to continue the working relationship developed with Alaska Railroad staff and have the Alaska Railroad participate in the design phase of this project. The AF is in the design process early enough to provide some flexibility in the project which could reduce the threat to area wildlife posed by the contamination on Alaska Railroad property, while at the same time cleaning up contamination at EAFB.
It is in the mutual interest of the AF and Alaska Railroad to construct the wetlands in the area of the "snow melt" pond. From the AF perspective, the pond is the best location to construct a wetland in relationship to the groundwater seeps. For the Alaska Railroad, it would eliminate the risk posed by the PCBs found in the pond. Since most of the remedial action designed to reduce the threat of contamination would need to be placed on Alaska Railroad property, this is an opportunity for the AF and Alaska Railroad to work together to solve the contamination problem and better the environment. AF has enclosed a draft Memorandum of Agreement for the railroad consideration. The agreement proposes the design, construction, and operation of the remediation facilities by the AF with the use of the necessary Alaska Railroad property being contributed by the Alaska Railroad as consideration for the benefit to be derived from the project. |
Ray Burger |
| 6/15/1995 |
Site Ranked Using the AHRM |
Initial ranking. Action code added because it wasn't when the site was originally ranked. |
Ray Burger |
| 7/27/1995 |
Update or Other Action |
Ship Creek Bioassessment Investigation prepared by Pacific Northwest Laboratory received. Pacific Northwest Laboratory (PNL) was asked by Elmendorf Air Force Base (EAFB)
personnel to conduct a series of collections of macroinvertebrates and sediments from Ship
Creek to
(1) establish baseline data on these populations for reference in evaluating possible impacts from Comprehensive Environmental Response, Compensation, and Liability Act (CERCLA) activities at two operable units,
(2) compare current population indices with those found by previous investigations in Ship Creek, and
(3) determine baseline levels of concentrations of any contaminants in the sediments associated with the macroinvertebrates.
A specific suite of indices established by the U.S. Environmental Protection Agency (EPA) was requested for the macroinvertebrate analyses; these follow the Rapid Bioassessment Protocol developed by Plafkin et al. (1989) and will be described below. Sediment sample analyses included a Microtox bioassay and chemical analysis for contaminants of concern. These analyses included, volatile organic compounds (EPA method 8010/8020), total gasoline and diesel hydrocarbons (EPA method 8015, CA modified), total organic carbon, and an inductive-coupled plasma/mass spectrometry (ICP/MS) metals scan.
Chemical analysis of these sediments suggests no Impact due to EAFB CERCLA program
contaminants of concern. Chlorinated solvent components· were not found above method detection
limits. Diesel fuel components were also not found.
The presence of gasoline components and toluene from the same samples, Transects 1 and 5, is suggestive of some contamination because of fuel; however, in all cases the values are far below applicable or relevant and appropriate regulations (ARAR) action levels (Level A, State of Alaska TPH-Gasoline = 50 mg/kg and BTEX = 10 mg/kg). The confirmation of fuel-derived hydrocarbons from both analyses in the same samples supports the validity of the data. |
Louis Howard |
| 4/3/1996 |
Update or Other Action |
Memorandum from Air Force received on the Time Extension on OU5 Remedial action. Attachment B to the Remedial Design/Remedial Action (RD/RA) scope of work states that the RA at OU5 is to begin on May 1, 1996. Based upon delays caused by the need to comply with statutes and regulations governing the acquisition of property, the AF anticipate that they will need a 60 day extension to commence construction of the remedial action.
In order to construct the RA at OU5, the AF needs the use of the property owned by the Alaska Railroad (ARR). More than 1 year ago, the Army Corps of Engineers (COE) began negotiations with the ARR to acquire the use of their property. Despite assurances from the ARR that they intend to lease the required property to the AF, a formal agreement has not yet been finalized. The obstacle to finalizing their agreement has primarily been clauses in the agreement proposed by the ARR which violate federal government contracting statutes.
The AF has diligently attempted to resolve differences with ARR. The AF has adjusted road construction and parcel size to meet their requests. It appears that the issue of compensation has been resolved; however, the exact language of the agreement has not yet been completed. On approximately March 2, 1996 the COE, on behalf of the AF, provided the ARR another proposed agreement. Based upon the comments from the ARR's vice president in charge of real property, the AF believe they are very close to reaching agreement; however, as on numerous occasions in the past, it is proving difficult to obtain a response from the ARR. As of March 26, 1996, the last proposed agreement was still under review in the ARR's legal office.
Pursuant to Section 25.1 (Extensions) of the Federal Facility Agreement, the Air Force requests a 60 day extension to begin construction of the remedial design. Good cause for this extension exists pursuant to section 26.1 (Force Majeure) of the FFA and the need to comply with the federal government contracting requirements. |
Ray Burger |
| 6/24/1996 |
Update or Other Action |
Easement between the Air Force (AF) and Alaska Railroad Corporation (ARRC) was signed by the AF (Frank Destadio Colonel USAF Civil Engineer HQ Pacific Air Force) on June 24, 1996 and the ARRC Vice President, Real Estate and Facilities John G. Burns. ARRC Contract Number 7114/USA Contract Number DACA85-9-96-90 for the sum of $147,000.00 granted an easement in and to ARRC's property to be used for the purpose of remediating certain contamination associated with Operable Unit 5. The ARRC does not object to the ROD and the AF will not seek or agree to any change in the FFA, ROD, Remedial Design without prior notice and opportunity to comment being afforded to the ARRC.
Duration of the easement is temporary and rights granted shall terminate upon completion of the remediation required by the ROD but shall not extend beyond April 1, 2026. The AF will give the ARRC not less than sixty days prior written notice of its intent to terminate the easement. Subject to existing property rights, ARRC reserves the right of ingress and egress from the easement area and the right to enter any part of the property including structures thereon, for the purposes of inspection at any reasonable time, and in time of emergency.
The AF shall not grant to any person or entity permission to use the easement area for any purpose other than environmental remediation set forth in the ROD. ARRC specifically reserves the right to grant permission to others to use and occupy the real property subject to this easement. As to Parcel 5, said use and occupancy will not unreasonably interfere with the AF's use of the easement. As to Parcels 1 through 4, said use and occupancy will not interfere with the AF's use of the easement as determined by the AF in its sole discretion, which will be exercised reasonably and in good faith. However, no conveyance of title, easement or other interest in the property shall be consummated without provisions for the continued operation of the treatment facilities or other response actions on the property as required by the ROD.
To the extent practicable, the ARRC shall notify the AF, ADEC, and the EPA by certified mail, at least thirty (30) days prior to any conveyance, of the ARRC's intent to convey any interest in the property and the provisions made for the continued operation of monitoring wells, treatment facilities, or other response actions installed pursuant to the ROD. This easement runs with the land and is binding upon any successors in interest to either party hereto. Total acreage is 12.891 acres: Parcel 1, 2.063 acres; Parcel 2, 0.390 acres; Parcel 3, 7.224 acres; Parcel 4, 0.582 acres; and Parcel 5, 2.632 acres all located in the U.S. Survey Number 9112 and Number 9017, Sections 8 and 9 of Township 13 North, Range 3 West, Seward Meridian, Anchorage Recording District, Municipality of Anchorage, Third Judicial District. |
Jennifer Roberts |
| 10/17/1996 |
Update or Other Action |
Air Force memo: Restricted Use of the Shallow Aquifer on EAFB signed by William R. Hanson P.E. GM-14 Chief Environmental Flight dated October 17, 1996 Memorandum for 3 SPTG/CEC/CEO from 3 SPTG/CEV
1) Due to the contamination and commitments to EPA/DEC the use of the shallow aquifer for any purpose on is not allowed. Attached Facilities Board minutes-03/29/1994 0930 Item 9 has Mr. William Hanson, briefing the Board on the policy to not use the shallow aquifer due to contamination. The Board approved this policy. Minutes approved by Thomas R. Case Brigadier General USAF Commander. The IRP has RODs for OUs 3 and 6 which require, the aquifer remain unused.
2) Personnel in the review process within CES must be aware of these policies and review them on a recurring basis. It is imperative this restriction be recognized and observed during engineer reviews and operations. |
Louis Howard |
| 1/17/1997 |
Update or Other Action |
This letter is written to officially notify the Air Force of our change in Project Managers for
Elmendorf Air Force Base. Louis Howard is replacing me as our lead project manager. He will now
be handling all operable units as well as basewide activities under the FFA. Please direct future project correspondence to Louis. He can be reached at the same mailing address, phone # 269-7552, or via facsimile at 269-7649. |
Ray Burger |
| 1/21/1997 |
Document, Report, or Work plan Review - other |
ADEC commented on the Final Results SERA Phase III Investigation, Technical Memorandum dated Oct. 25, 1996 which included ST76, ST77, ST79, SS80. ST76 Monitoring well 76WL01: Samples collected from the soil borings at this site did not contain elevated concentrations of petroleum
hydrocarbons. No source or secondary source of contaminants was found that would necessitate soil
remediation. However, the water sample collected from monitoring well 76WL0 1 contained 11.7 mg/L diesel range hydrocarbons. A groundwater sample collected from an upgradient monitoring well (OU5MW4) during the OU5 RI contained <1 mg/L. Thus, the source of the diesel range hydrocarbons in groundwater beneath ST76 is unclear.
Additional groundwater monitoring and evaluation are warranted. Following submittal of the complete assessment report and assuming no QA/QC problems exist, please prepare a brief corrective action plan that calls for additional groundwater monitoring at wells 76WL01 and OU5MW4. An evaluation of the groundwater monitoring well network is also necessary to determine if a downgradient well exists that would provide more information on the extent of groundwater impacts in this area. It may be necessary to install additional wells. I recommend a short scoping meeting to review the existing groundwater information and plan the additional monitoring. |
Louis Howard |
| 3/13/1997 |
Update or Other Action |
Action 3/13/97, based on Relative Risk Evaluation worksheet dated 8/16/95. Pathway: On top of a 60' bluff. Soils consist of mixtures or beds of gravel and sand with small amounts of silt. Bootlegger Cove clay is confining layer between the shallow and deep aquifers. Shallow GW is 40 feet below ground surface at top of bluff and flows out as seeps toward bottom of bluff. No drinking water wells in shallow aquifer. Seeps flow into wetlands. Contaminant migration in surface water and sediment is strongly influenced by spring thaw. Ship Creek runs on downgradient side of this site and appears to be a gaining stream. Receptors: Backup drinking water wells in the area are in deep aquifer. |
Louis Howard |
| 11/18/1997 |
Meeting or Teleconference Held |
Restoration Advisory Board meeting held to discuss: Five of seven new RAB members welcomed and briefed on responsibilities, revised charter signed, restoration program overview, including budgets, accomplishments and future work, review of 1997 fuel spill cleanup efforts, review of budgets for the Quality and Conservation branches, review of PL81 pipeline removal project, poster displays: Restoration overview, Natural Resources overview, Six Areas of Concern and Geese Management. |
Louis Howard |
| 2/20/1998 |
Document, Report, or Work plan Review - other |
EPA and ADEC project managers inspected the revised IC documentation February 20, 1998 at the Base and concurred that the controls were in place, and were operational and functional. |
Louis Howard |
| 3/24/1998 |
Document, Report, or Work plan Review - other |
Staff commented on the Draft Wetland Remediation System Startup Report dated January 1998 from the USAF. ADEC agrees that 8015M will need to be modified to have detection limits lower than the cleanup levels established in the OU5 ROD. However, rather than using 8015M, the AF may wish to use the methodology found at 18 AAC 70.020 (see note 8 to the table found in regulations). The AF may wish to use 8015M by its labs if the lower detection limit is attainable with modification which will require ADEC and EPA concurrence. |
Louis Howard |
| 4/20/1998 |
Document, Report, or Work plan Review - other |
Staff commented on the OU5 Surface Water Quality Analyses at EAFB. ADEC has the following comments regarding the use of fuel ranges, 18 AAC 70.020 and lab methods for determining cleanup levels for surface water. Since Alaska Water Quality Standards (AWQS) do not specifically address JP-4, TFH-diesel, or TFH-gas, it is more important for the AF to utilize lab methods which will detect the levels present in surface water for total aqueous hydrocarbons (TAqH) and total aromatic hydrocarbons (TAH).
ADEC requests the AF use the sample methodology found in Alaska Water Quality Standards (AWQS) for freshwater uses 18 AAC 70.020 (see note 8 to the table) for determining cleanup levels in surface water.
The explanation regarding analysis of TAqH and TAH instead of specific fuel ranges is best served by inclusion in the "Lessons Learned" section of the remedial action report for OU5. It is ADEC's determination that the use of alternative lab methods vs. EPA method 8015M does not change the selected remedy found in the ROD nor does it change its overall protectiveness. |
Louis Howard |
| 4/24/1998 |
Document, Report, or Work plan Review - other |
Staff commented on the Operable Unit (OU) 5 Draft final Remedial Action Report dated April 1998. The table 2-1 on page 2-2 incorrectly references cleanup standards for JP-4, TFH-Gas and TFH-Diesel as being 10 ug/l for total hydrocarbons. ADEC requests the AF add language to footnote (b) to the table which states: the surface water standard for total aromatic hydrocarbons (TAH) was used. Apply this language to footnote (b) in Table 3-1 on page 3-5 for water standard for hydrocarbons.
ADEC requests additional information on the names of the contractors and roles they fulfilled in the major design and remedial action for OU5. Finally, provide information on the amounts of gravel used and amended topsoil used on top of the sediments at the snowmelt pond and at the bottom of the wetland remediation system, and the seep areas covered by the 1 foot layer of gravel.
Also on the same day, ADEC provided comments on the Draft Base wide Environmental Monitoring Plan dated April 1998. ADEC concurs with the removal of wells or elimination of analytical methods from the EAFB monitoring program. However, the regulatory agencies may determine, after consultation with the AF, that sampling of additional active wells, inactive wells, or analytes previously eliminated from the ongoing monitoring program may be necessary. |
Louis Howard |
| 5/1/1998 |
Update or Other Action |
Based on discussions in May 1998 between the Alaska Department of Environmental Conservation (ADEC), U.S. Air Force (USAF), and U.S. Environmental Protection Agency (USEPA), the analytical list was changed from EPA Method 8015M to include EPA Methods 602 for benzene, toluene, ethylbenzene, xylene (BTEX) and 8310 for PAH. Both methods have lower detection limits below 10
ug/L and allow for analysis of fuel hydrocarbon components. The lower detection limits have allowed for improved monitoring of contaminant concentrations that may exit the system in the effluent water.
No elevated contaminant concentrations were reported exiting the Wetland Remediation System (WRS) during the 1997-1998 Operations & Maintenance period. Analytical methods for Nitrate-Nitrite and Total Phosphorus were also updated. The methods are now Method E353.2 for Nitrate-Nitrite and E365.3 for Total Phosphorus. The new analytical methods do not quantify the identified contaminants of concern (COCs) specified in the OU 5 record of decision (ROD) (USAF 1995a), but are appropriate for determining contaminant levels and monitoring the effectiveness of the wetland system.
Since the new analytical methods do not quantify all of the specified COCs, clean-up levels from
the Alaska Water Quality Standards, 18 AAC 70.020, are utilized for comparison purposes. The Alaska Water Quality Standards for petroleum hydrocarbons, oils and grease contamination concerns for growth, and propagation of aquatic and wildlife specify 10 (ug/L maximum concentration for Total Aromatic Hydrocarbons (TAH) and 15 gg/L maximum concentration for Total Aqueous Hydrocarbons (TAqH). TAH and TAqH concentrations were determined from the BTEX (E602) and PAH (8310) analytical results. TAH concentrations were determined by summing the concentrations of all detected BTEX. TAqH concentrations were determined by summing the concentrations of all detected PAHs and BTEX compounds. These clean-up levels are required for the Wetland Cell effluent. |
Louis Howard |
| 5/1/1998 |
Update or Other Action |
Basewide GW Modeling Report received. This report describes the methodology employed & results derived from a GW modeling task conducted at Elmendorf Air Force Base (AFB). Modeling was performed of GW flow primarily beneath the developed portion of the base, commonly referred to hydrogeologically as the outwash plain. This effort is the latest in a series of tasks that have characterized subsurface GW flow & contaminant transport in this vicinity. The initial task was performed in 1994 to support the Operable Unit (OU) 5 Feasibility Study (FS) (USAF, 1994).
A later effort conducted in 1996 was a follow-on program to validate the transport model, adjust the transport parameters, & update the contaminant sources & GW concentration with 1996 information (USAF, 1997a). This effort is intended to evaluate the impacts of three recent spills & other new sources upon local GW quality & the future quality of discharges to Ship Creek.
The concentration of benzene in a benzene-saturated GW solution using the preceding assumptions is 54 mg/L. The value was calculated as the product of the mole fraction of benzene in the fuel & the theoretical solubility of benzene in water (Lyman et. al., 1992). As a consequence of the two initial assumptions, this value is extremely conservative. Biodegradation, volatilization, & other weathering processes undoubtedly reduce the concentrations of the water-soluble components in the free-phase product. The fuel benzene concentration of 3% corresponds to fresh gasoline; estimates of benzene concentrations in various jet fuel varieties (e.g. JP-4 & JP-5) are less than 1% (Riser-Roberts, 1992). Furthermore, the maximum benzene concentration observed in laboratory gasoline - water mixtures is approximately 30 mg/L (Lyman et al., 1992, Calabrese & Kostecki, 1989).
The maximum benzene concentrations reported through the basewide monitoring program are generally less than 1.0 mg/L (USAF, 1997b). Nevertheless, an initial benzene concentration of 54 mg/L was assigned to the grid elements corresponding to Spill 3 in order to assess the sensitivity of the transport simulations to this highly conservative estimate. This value corresponds to the theoretical benzene concentration calculated for GW in contact with fuel & saturated with respect to benzene.
In conclusion, it may be stated that the current modeling study predicts that there is little likelihood of benzene discharging into Ship Creek. Even though the most recent analytical data were incorporated in the model, including additional SERA sites not previously modeled as well as the three recent spills, downgradient migration of benzene from the source areas is predicted to be essentially prevented through the degradation of benzene. The half-life employed for benzene in this study, as well as all other model parameters (with exception of the source concentrations) were left unchanged from those employed during the 1996 model validation/calibration study.
Sources of uncertainty potentially affecting contaminant transport still include source strengths & the time frame that each source is assumed to remain active. Greater source strengths & longer active time frames (as exemplified in Section 3.2 for Spill 3) can significantly impact the time frame required for benzene attenuation. Nevertheless, even if it takes longer for benzene to degrade to concentrations below the MCL in the presence of stronger & more persistent sources, it still appears that downgradient migration is largely controlled by degradation of benzene, thus minimizing the potential impact to Ship Creek.
Based on the results of this modeling study, it is recommended that benzene contamination in GW throughout the model area continue to be monitored over time. If significant downgradient migration was detected in the future, additional adjustments could be made to critical model parameters, such as the half-life of benzene in the GW, or the rate at which mass enters the system from a source which is considered to be active. Furthermore, a refined model could be utilized to predict the migration behavior of benzene in the GW in critical areas, such as the area of Spill 3. However, at this point the model calibration/validation effort conducted in 1996 appears to be accurately predicting the migration behavior of benzene contamination in GW. |
Louis Howard |
| 7/24/1998 |
Update or Other Action |
U.S. Air Force (USAF) sent in an action memorandum for the results from the analytical testing of the soil in landfarm at Elmendorf Air Force Base ( EAFB). Attached was a copy of the results from analytical testing of the OU5 soil in the landfarm. The contaminated soil from the remedial construction of the wetland remediation system/overland cell/wetland cell at OU5 was sampled after being treated in the landfarm in the vicinity of LF05 in OU1. This sampling was conducted on May 13, 1998. The highest diesel range organic (DRO) contamination from the samples was 652 mg/kg. The OU5 Record of Decision set the soil cleanup level at 1,000 mg/kg for DRO.
Since the soil is below the cleanup level no further action is required for the soil. AF would like to use the soil as fill material at non-residential location on Base. This information is in the Remedial action report for OU5, but the AF would like to be able to move it sooner than the finalization date of the report so the landfarm area can be turned into a compost area for the Base. ADEC signed its concurrence July 28, 1998. |
Louis Howard |
| 7/31/1998 |
Update or Other Action |
7/98 remedial action report received. Only the upper aquifer has contaminated groundwater. Two plumes of impacted groundwater have been located in the upper aquifer. In the western area, an approximately 1,000 foot wide plume. There is no standard for TFH-gas and diesel for groundwater contains TCE, JP-4 jet fuel, diesel fuel, gasoline, and benzene. At the eastern end of the OU, an approximately 1,000 foot wide plume contains gasoline and TCE. Additionally, there are several seeps at OU 5. The seeps are groundwater that seeps from the face of the bluff. The groundwater emerges as surface water at seeps so the surface water standard for total aromatic hydrocarbons was used. 18 AAC 70.020. Based on ecological risk (protective of aquatic resources).
The current detection limit for EPA Method 8015M for purgeable and extractable petroleum hydrocarbons in water ranges from 50 to 100 ug/L; this is based on the standard laboratory procedure without modification. Analytical results were nondetect for the detection limits used for EPA Method 8015M.
However, analyses performed on the startup period samples did not meet the detection limit of 10 ug/L for TFH-Gas and JP-4. Cleanup levels for OU 5 are well below established detection limits for the analyses that were approved in the Workplan (USAF, 1996d) for analysis of water samples from the system. In order to meet the 10 ug/L for TFH-Gas and JP-4, the analytical methods for OU 5 have been changed to include EPA Methods 602 for BTEX and 8310 for PAH.
Table 3-1 seems to indicate that the levels of total fuel-range hydrocarbon (TFH) gasoline and diesel are increasing. This could be the result of different analytical reporting methods which are not comparable. The maximum concentrations from the ROD were determined using California Leaking Underground Fuel Tank (LUFT) methods 8015MP and 8015ME, respectively.
This is a hydrocarbon scan method that quantifies the total amount of gasoline, diesel, and unidentified organics. The 1997 results report all hydrocarbons in the gasoline range (C6-C10; ADEC Method 8015M) and the diesel range (C10-C28; ADEC Method 8100M), rather than the specific fuels observed as in the LUFT hydrocarbon scan. Since neither the 8015M methods nor the 8100 M were able to meet the required detection limits, these methods were changed to EPA Methods 602 for BTEX and 8310 for PAH. These methods will also eliminate the possible different interpretations of the results from the LUFT method and reporting all hydrocarbons in a range.
It states DRO contaminated soils, GRO, DRO, benzene, TCE contaminated groundwater will meet cleanup levels in 15 years. Remedy is operational and functional. ICs are in place and working as planned. |
Louis Howard |
| 8/12/1998 |
Document, Report, or Work plan Review - other |
Letter to AF regarding Response to Comments on draft work plan SERA Phase II Sites ST36/66, ST74, and ST61 Investigation dated July 1998. ADEC disagrees with contractor's response to comments concerning analytical methods discussed in Items 1(i) and 1(m). UST and CS regulations require cleanup levels for GRO/DRO be based on analyticals using AK methods not 8015M/8100M.
The only exception to the analytical methods are found in 18 AAC 78.090: "If site assessment sampling began before November 3, 1995, and if test results satisfy the water quality criteria and cleanup levels referred to in (i) of this section, the owner or operator may continue to use the analytical methods used before that date to complete the site assessment. If a site assessment is begun on or after November 3, 1995, the owner or operator shall use the analytical methods set out in Table G of 18 AAC 78.800(b)."
ADEC requests the AF cease use of alternative lab methods (8015M/8100M) for DRO and GRO analyses by the end of the calendar year for soil and groundwater analysis or long term monitoring which do not include AK 101 or 102. The alternative methods will no longer be acceptable when the new 18 AAC 78 and 18 AAC 75 regulations become final.
It is anticipated that the UST and CS regulations will become finalized by the end of this calendar year. Please make changes to any future contracting or scopes of work to ensure that by March 1, 1999 all analyses for gasoline range organics and diesel range organics utilize AK methods for both soil and groundwater. |
Louis Howard |
| 10/27/1998 |
Update or Other Action |
07/98-09/98 quarterly progress report received. 3,000 cubic yards of soil contaminated at ST37 excavated and treated at an on base treatment facility (closeout in process), monitored natural attenuation to be relied on to attain cleanup levels in contaminated shallow aquifer and surface water other than seep water at ST37. Seep water in western and middle portions of OU5 ST37 is passively drained using horizontally drilled extraction wells in the bluff. Water flows through constructed wetland at the location of the snow melt pond. The snow melt pond's low level PCB contamination was covered by gravel prior to the wetland cell construction. Institutional controls remain in place for the shallow aquifer prohibiting use and thereby preventing exposure by humans until cleanup levels are achieved (MCLs). 12.3 million gallons of water have been treated by the wetland system. Continued surface water sampling shows no detectable contaminants being discharged from the wetland system. |
Louis Howard |
| 11/25/1998 |
Update or Other Action |
ADEC and AF sign Technical Document to Support No Further Action for ST76 at Bldg. 9-154 (now Bldg 5374).
Samples collected from the soil borings at this site did not contain elevated concentrations of petroleum hydrocarbons. No source or secondary source of contaminants was found that would necessitate soil remediation.
A water sample collected from monitoring well 76WL01 contained 11.7mg/L diesel range hydrocarbons. This well was added to the basewide monitoring program for monitoring. Based on this action, ADEC agreed to withdraw their request for groundwater monitoring under the SERA III program.
Monitoring well 76WL01 is still being monitored in basewide program under OU5. See attachment d for current results of sampling at 76WLO 1. The remedy of no further action under the ERP is selected because the contaminant levels at the site present no significant threat to human health or the environment: thus, no treatment is necessary. |
Louis Howard |
| 12/17/1998 |
CERCLA ROD Periodic Review |
Announcement of the Five-Year Review Findings which show that the remedies in place to address contamination are protective & operating as designed. Anchorage Daily News 12/13-15/98 & Alaska Star 12/17/98.
Current Status
All remedial actions are operational & functional, as documented in the OU5 RA report (USAF, 1998c). The ST37 wetland system is operational & the O&M manual is being written. GW monitoring & sediment sampling is continuing at OU5 & upgradient locations in accordance with the Environmental Monitoring Plan (USAF, 1997c). The ST37 wetland system & all monitoring wells have been inspected & are in good condition. Institutional controls have been established & are being maintained to prevent exposure until cleanup goals are attained throughout OU5.
Analytical results from the startup period of the wetland remediation system show that the system is performing as designed. The current detection limit for EPA Method 8015M for purgeable & extractable petroleum hydrocarbons in water ranges from 50 to 100 [tg/L; this is based on the standard laboratory procedure without modification. Analytical results were nondetect for the detection limits used for EPA Method 8015M. However, analyses performed on the startup period samples did not meet the detection limit of 10 pg/L for TFH-Gas & JP-4. Cleanup levels for OU 5 are well below established detection limits for the analyses that were approved in the Workplan (USAF, 1996d) for analysis of water samples from the system. In order to meet the 10 jpg/L for TFH-Gas & JP-4, the analytical methods for OU 5 have been changed to include EPA Methods 602 for BTEX & 8310 for PAH.
Site conditions & land use are consistent with the OU5 ROD requirements & remain protective, based on evaluation of current monitoring data & trends, & the most recent joint inspection conducted by the USAF, EPA & ADEC project managers on February 20, 1998. Shallow contaminated soils at the four seep locations were removed during construction of the wetland system. These soils were placed in a land-farm & are awaiting confirmation sampling to ensure that cleanup goals have been reached. No other monitoring of shallow soils is being done at these sites.
The maximum concentrations from the ROD were determined using California Leaking Underground Fuel Tank (LUFT) methods 8015MP & 8015ME, respectively. This is a hydrocarbon scan method that quantifies the total amount of gasoline, diesel, & unidentified organics. The 1997 results report all hydrocarbons in the gasoline range (C6 -C10 ; ADEC Method 8015M) & the diesel range (C1 0-C2 8; ADEC Method 8100M), rather than the specific fuels observed as in the LUFT hydrocarbon scan. Since neither the 8015M methods nor the 8100 M were able to meet the required detection limits, these methods were changed to EPA Methods 602 for BTEX & 8310 for PAH. These methods will also eliminate the possible different interpretations of the results from the LUFT method & reporting all hydrocarbons in a range.
COCs in sediments at ST37 & GW in the shallow aquifer still exceed cleanup goals. Summaries of monitoring information are available in the 1997 GW Monitoring Annual Report. Due to current land use & institutional controls, there is no human & ecological exposure to the GW. Response actions at OU5 are ongoing & are expected to continue for another 23 years, based on current estimates of the time to remediation documented in the 1997 GW Monitoring Annual Report.
The OU5 remedies remain protective of human health & the environment & are functioning as designed. OU5 remedies will be addressed in future periodic reviews &, if necessary, further actions will be evaluated.
Future five-year reviews are necessary because contamination remains above levels that allow for unrestricted use &/or unlimited exposure at OUs 1, 2, 4, 5, & 6. The next five-year review will be completed by August 2003. |
Louis Howard |
| 1/12/1999 |
Update or Other Action |
10/98-12/98 quarterly progress report received. Five year review document signed by EPA and ADEC stating the remedy is operational, functional and remains protective of human health and the environment. Round 2 sampling of 20 wells, 6 exceeded MCLs for trichloroethylene (5ug/L). Pump seal failed at wet well #1 and backup well operated as designed so operation of system not compromised. |
Louis Howard |
| 4/13/1999 |
Update or Other Action |
01/99-03/99 quarterly progress report received. Iron precipitate removed from overland flow cell, pump seal failure at wet well #3 and alternate backup pump operating properly so operation of system is not affected. |
Louis Howard |
| 4/22/1999 |
Document, Report, or Work plan Review - other |
Staff sent a comment letter to the AF regarding the Draft 1998 Annual Report OU5 Wetland Remediation System dated March 1999. ADEC is requesting the AF and EPA consider adding analysis for trichloroethene (TCE) at the wetland remediation system (WRS) and seeps. The rationale behind ADEC's request is that the monitoring well OU05-MW-02 has detected TCE at 11.1 ug/l and may or may not be indicative of a bigger plume of chlorinated solvents progressing through OU5. Additionally, OU5 receives 90% of the shallow groundwater aquifer and surface water flow from the Base (see OU5 remedial action report 1.2 page 1-1).
Since there is not any current data on TCE from the seeps nor from the WRS, it is hard for the AF to state that TCE from other source areas has not reached these areas or if TCE is more extensive than the data suggests. The beaver pond at sampling point SC-3 has had TCE persist at levels above the MCLs (USAF Appendix C Base wide Annual Groundwater Report February 1999). |
Louis Howard |
| 7/8/1999 |
Update or Other Action |
04/99-06/99 quarterly progress report received. October 2025 remains the target date to meet cleanup of: groundwater-TCE, benzene, TFH diesel and gas, surface water-sheen, TFH gas and JP4. Note for TFH and other fuel ranges Alaska water quality standards for total aromatic hydrocarbons will apply, e.g. 10 ug/L. |
Louis Howard |
| 10/5/1999 |
Update or Other Action |
07/99-09/99 quarterly progress report received. Continued long term operation and maintenance of wetland system, surface water sampling at system shows no detectable contaminants being discharged from the system. Base wide sampling shows of the 20 OU5 wells sampled, 5 exceed the MCL for TCE, surface water sample SC-3, at the beaver pond, exceeds the MCL for TCE at 6.6 ug/L in August 1999. Note the 1997 ambient water quality criteria for freshwater acute and chronic lowest observed effects are much higher at 45,000 ug/l and 219,00 ug/l respectively. Finally, the April 1999 EPA H20 Quality criteria for human health consumption of water plus organism is 2.7 ug/L and for organism only at 81 ug/L. |
Louis Howard |
| 4/10/2000 |
Update or Other Action |
1 January- 31 March 2000 quarterly report received. Surface water sampling of wetland system indicated that no detectable levels of contaminants of concern have been discharge from the wetland system. Target date to meet cleanup levels is October 2025 (not known if this includes base wide groundwater COCs estimated to take longer than 2025). |
Louis Howard |
| 6/1/2000 |
Update or Other Action |
Environmental Monitoring Plan received. The purpose of the Basewide Environmental Monitoring Program (EMP) is to provide information on surface water and groundwater quality, groundwater flow characteristics, and monitoring well integrity at specified locations throughout Elmendorf AFB. The data assessment portion of the program includes data collection via groundwater and surface water sampling, and groundwater level measurements.
Groundwater samples will be collected biannually from 20 wells as part of the OU 5 Groundwater
Sampling Program. organics, total iron, and polynuclear aromatic hydrocarbons (PAHs). The methods prescribed for this OU are based on the decisions documented in the ROD for OU 5. These methods include, but are not limited to, constituents which have either exceeded MCLs or were identified as COCs during the RI/FS. Two constituents, benzene and trichloroethene (TCE) have been identified in excess of MCLs. Fuel constituents were also identified as COCs in the ROD.
The remedial action goal for OU 5 is to reduce these contaminant levels to below MCLs. Like
OU 1, the primary purpose of the long-term monitoring at OU 5 is to compare concentrations of these and other constituents in the samples collected to historic OU 5 concentrations and/or background concentrations, such that changes or trends in concentrations can be established. When sufficient data are collected, groundwater sampling results will be evaluated statistically to ensure that the assumptions made in the OU 5 ROD are accurate; to validate predictions made in the 1998 Groundwater Model; and to provide early warning of increased contaminant levels or migration of contaminant plumes.
At OU 5 (as well as at OU 1), establishing the levels of contaminants in key wells upgradient of
Ship Creek is essential to monitoring the potential for any adverse impact to this body of water due to OU 5 contaminant migration. As part of the Annual Report, all constituents of interest will be plotted against historic results, and conclusions will be drawn regarding the fate and transport of the OU 5 groundwater contaminants. Recommendations for changes in the sampling frequency or changes in the array of groundwater monitoring wells currently in the monitoring program will be included in the Annual Report as appropriate.
MTBE will be added to the list of compounds analyzed in the Method SW8260B volatile organics
analysis. This change is made as a result of a request by ADEC to monitor for this compound at all wells in the Basewide Sampling Program for one year. OU5: GRO (AK101) & DRO (AK102)-These two methods were removed and replaced with SW8310 as the reporting limits for both AK101 and AK102 were not low enough to meet OU 5 ROD cleanup levels.
Two plumes of impacted groundwater were delineated in the upper aquifer at OU 5. The original four COCs identified for OU 5 were referenced from the OU 5 ROD (USAF, 1995c) and consisted of benzene, diesel, gasoline, and TCE. The groundwater model for OU 5 indicates that in about 10 years the concentrations of benzene and TCE will diminish significantly and eventually be below detectable levels.
However, since proposed diesel and gasoline cleanup levels for OU 5 are well below technically achievable laboratory limits for their respective analyses, the following analytical method change was made: SW8015MP (hydrocarbons as gasoline) and SW8015ME (hydrocarbons as diesel) were dropped and replaced with SW8310 (polyaromatic hydrocarbons). As a result, ethylbenzene, toluene, and xylene were added to the COC list in place of diesel and gasoline since the method has a lower detection limit.
Surface water samples will be collected biannually from eight locations within OU 5. Seven of the locations are from within Ship Creek and one of the locations is from a beaver pond upgradient of Ship Creek. These surface water locations will be sampled concurrently with OU 5 groundwater sampling. Surface water samples will be analyzed for anions (nitrate and phosphate), trace metals, and volatile organics. In addition, samples from the furthest upstream location (SC-1B) and the furthest downstream location (SC-08) will also be analyzed for COD. The primary purpose of long-term monitoring at Ship Creek is to evaluate whether or not upgradient groundwater contamination is reaching the stream. |
Louis Howard |
| 9/13/2000 |
Document, Report, or Work plan Review - other |
Staff commented on the AF draft Annual Technical Report for OU5 Engineered Wetlands dated June 2000. Sampling should be increased for the seeps to better correlate data and better determine the effectiveness of the wetland remediation system. ADEC recommends the AF consider increasing sampling frequency at the seeps to match the schedule set for the pump stations, overland flow cell and the wetland cell. |
Louis Howard |
| 10/2/2000 |
Update or Other Action |
Quarterly progress report received for the 3rd quarter 1, July 2000-30 September 2000. Round 2 groundwater samples collected in August 2000. Continued long term operation and maintenance of the wetland remediation system. Continued surface water sampling of wetland system with no detectable contaminants of concern being discharged from the wetland system. Removed iron precipitate and vegetative growth from the overland flow cell in July 2000. Six wells exceeded the MCL for TCE. Surface water sample at SC-3 beaver pond exceeds 6 ug/L, but downstream from site at Ship Creek it degrades well below MCL. |
Louis Howard |
| 1/12/2001 |
Update or Other Action |
Quarterly progress report received for 4th quarter October 1, 2000 to December 31, 2000. 20 wells sampled and 6 wells exceeded MCL for TCE. Surface water SC-3 at beaver pond had TCE levels at 4.8 micrograms/liter which is down from 6 ug/L in Round 1 (October 00). |
Louis Howard |
| 3/1/2001 |
Update or Other Action |
The Early Warning Line (Plate 1) was established in 2001 to provide a early detection of
contaminant plumes that may threaten Ship Creek. The distance between the Early Warning Line and
Ship Creek represents the theoretical average distance groundwater would flow in two years. This
distance was selected because it represents the minimum possible time that the USAF would require to obtain funding for an active seep capture or other remedial activity to prevent impact to Ship Creek.
The actual distance in feet was calculated using boring logs and groundwater gradient data. Soil permeability was determined using published values for soil types encountered in soil borings. Conductivity values from an OU 5 pump test were also considered. Based on these data, a range of average linear velocity for groundwater was calculated. Velocities ranged from approximately 7 feet/year to approximately 1,000 feet/year. The Early Warning Line was drawn at the conservative end of this range and represents an average linear velocity of approximately 1,000 feet/year. Therefore, the Early Warning Line is located approximately 2,000 feet upgradient of Ship Creek. |
Louis Howard |
| 4/17/2001 |
Document, Report, or Work plan Review - other |
Overall, ADEC concurs with Elmendorf’s approach to reduce its groundwater monitoring costs while still providing protection to human health, safety, or welfare and the environment. With regards to decreasing the monitoring frequency in Operable Unit (OU) 1 to an annual basis, ADEC concurs. With regards to OU 6, ADEC recommends not discontinuing groundwater monitoring at well 703-WL-02 and to continue to monitor for methyl tert-butyl ether (MTBE). |
Louis Howard |
| 6/4/2001 |
Document, Report, or Work plan Review - other |
Staff concurred with the discussion and recommendations presented in the draft annual technical report for the wetland remediation system. |
Louis Howard |
| 6/27/2001 |
Update or Other Action |
Basewide Environmental Monitoring Plan received. The Basewide Environmental Monitoring Program addresses the needs for multiple programs at Elmendorf Air Force Base (AFB) (Figure 1-1), including the Federal Facilities Agreement (FFA), the State-Elmendorf Installation Restoration Agreement (SERA), & the Resource Conservation & Recovery Act (RCRA). As part of the Elmendorf AFB Environmental Restoration Program (ERP), this program will generate data on surface water quality, GW quality, GW aquifer characteristics, & GW monitoring wells. This report serves as the workplan for the 2001 Basewide Program.
The GW sampling program was formally initiated in 1995. Year 2001 GW
sampling as part of site-specific long-term monitoring programs will occur at Operable Units (OUs) 1, 2, 4, 5, & 6, at SERA Phase I & II, other miscellaneous SERA locations, & at the Taxiway "N". Since program areas in various portions of the Base are interconnected hydraulically, GW quality data collected will be integrated between the areas investigated, in a Basewide environmental evaluation. The findings will be reported in the Annual Report of Environmental Monitoring Activities, hereafter referred to as the Annual Report.
OU5 Wells removed from sampling: 76-WL-01 sampled from 1998-2000,OU5MW-01 sampled from 1995-2000 & OU5MW-11 sampled from 1995-2000. These wells were removed based on criteria established in the Basewide Decision Guide.
OU5 analytical methods removed from the basewide GW sampling program. GRO AK101 & DRO AK102. These two methods were removed & replaced with SW8310 as the reporting limits for both AK101 & AK102 were not low enough to meet OU 5 ROD cleanup levels.
In 2000, methyl tertiary butyl ether (MTBE) was added to the analyte list for all wells to gather baseline data at the request of the ADEC. MTBE was only found in three wells during the 2000 sampling program. These wells were OU5MW-09 in OU5, 703-WL-02 & 403-MW-01 in the SERA Miscellaneous Site. At OU5MW-09, MTBE was only detected during Round 2 at 0.1 microgram per liter (tug/L). The result was qualified with an "F' since it was detected below the method reporting limit. At 703-WL-02, MTBE was detected during the first round at 7 jig/L. The result was qualified with an "R" because it was not a confirmed result (as required by the SW8021B method). At 403-MW-01 MTBE was detected during the first round at 0.9 jtg/L. The result was also qualified with an "R". The MTBE results during Round 2 for 703-WL-02 & 403-MW-01 were below the method detection limit by method SW8260B. As part of the 2001 program, MTBE will only be analyzed at well 703-WL-02 (SERA Miscellaneous sampling unit), per ADEC request. Method SW8260B will be used for this MTBE analysis.
The remedial action goal for OU 5 is to reduce these contaminant levels to below MCLs. Like OU 1, the primary purpose of the long-term monitoring at OU 5 is to compare concentrations of these and other constituents in the samples collected to historic OU 5 concentrations and/or background concentrations, such that changes or trends in concentrations can be established. Groundwater sampling results will be evaluated statistically to ensure that the assumptions made in the OU 5 ROD are accurate; to validate predictions made in the 1998 Groundwater Model; and to provide early warning of increased contaminant levels or migration of contaminant plumes. |
Louis Howard |
| 10/4/2001 |
Offsite Soil or Groundwater Disposal Approved |
DOWL Engineers - request (Work Order # D57267) for approval for soil disposal from US ARMY CORPS of Engineers Building 21-700 UST (now Bldg. 2204) granted by John Halverson.
Heather Newman from DOWL Engineers (DOWL) is requesting approval from the State of Alaska Department of Environmental Conservation (ADEC) for the transportation of up to approximately 40 cubic yards of petroleum-contaminated soil from the 19oation of a heating oil underground storage tank (UST) at the Corps of Engineers building at 2204 3 Street on Elmendorf AFB to Alaska Soil Recycling's (ASR) First Avenue facility in Anchorage, Alaska. As wo discussed on the telephone, contaminated soil was encountered during excavation activities the first week of August to determine the location of utilities over the fop of the tank.
Soils will be transferred to ASR as covered loads in dump trucks. As required by the ADEC,
analytical results for the post treated soil will be provided when available. •
Attached are analytical results for product that was contained in the tank. Results indicate the only detected compound analyzed for was diesel range organics (DRO). |
John Halverson |
| 1/2/2002 |
Update or Other Action |
Staff received the seventh Annual Report of Groundwater Sampling Activities developed for the
Elmendorf Air Force Base (AFB) Basewide Environmental Monitoring Program, hereafter referred to
as the Basewide Program. The Basewide Program encompasses two field programs, the Basewide
Groundwater Sampling Program and the Basewide Water Level Monitoring and Well Optimization
Program. This Annual Report of Groundwater Sampling Activities contains a summary of 2001 water
quality data and interpretations from the Basewide Groundwater Sampling Program. The Annual
Technical Memorandum (United States Air Force [USAF], 2002a) developed and distributed as a
separate deliverable report, addresses activities associated with the Basewide Water Level Monitoring and Well Optimization Program.
The Basewide Program was established through the Elmendorf AFB Installation Restoration
Program (IRP) to address the needs of multiple programs on the base. These programs include the
Federal Facilities Agreement (FFA), and the State-Elmendorf Environmental Restoration Agreement
(SERA). Over the following two program years, 2002 and 2003, the focus of the Elmendorf AFB
Basewide Program will be modified to reflect the requirements outlined in appropriate Records of
Decision (RODs), decision documents, corrective action documents, and/or any other binding
agreements. In an effort to optimize the program, several changes may occur in sampling frequency, in the wells sampled, and in groundwater seep sampling.
The following are conclusions derived from intuitive and statistical analysis of 2001 groundwater data for OU 5:
* As a result of the 2001 Decision Guide analysis, none of the wells or analytical methods met the criteria for removal from the OU 5 program area.
* For wells in the OU 5 program area, free product was not detected at any well location during
the 2001 field season. Although no measurable quantity was noted, a fuel odor was detected at
wells 48-WL-03, GW-4A, OU5MW-13, and OU5MW-16.
* TCE was the only COC detected at concentrations above the MCL in 2001. TCE at well OU5MW-08, previously below the MCL (5 ulg/L), was found above the MCL in 2001. Statistical analysis indicates a significant increasing trend for TCE at this location and also at upgradient
well OU5MW-07. The data indicate that TCE is migrating toward Ship Creek at concentrations
exceeding the MCL.
* Eleven wells at OU 5 contained statistically valid trends using current available data for benzene. None of the 2001 data from OU 5 wells exceeded the MCL of 5 ug/L for benzene.
* Nine wells at OU 5 contained statistically valid trends using current available data for TCE. An increasing TCE trend was apparent at three wells (OU5MW-07, OU5MW-08, and OU5MW-31); three wells had decreasing trends (NS3-02, OU5MW-06, and SP1-02); and stable concentrations were calculated for two wells (OU5MW-14 and SP2/6-05). The TCE MCL was exceeded at wells 48-WL-03, GW-4A, OU5MW-02, OU5MW-06, OU5MW-07, OU5MW-08, and SP1-02. It was noted that in 1999 TCE levels at well GW-4A were below the MCL for the first time since sampling was initiated in 1994, but were back up above the MCL in 2000 and in 2001.
* It is recommended that a downgradient well for the TCE plume associated with well 48-WL-03
be installed to delineate the lateral extent of this plume and to more effectively monitor natural attenuation of this plume.
* It is also recommended that well OU5MW-15, a downgradient well for the TCE plume associated
with well SP1-02, be sampled to more effectively monitor natural attenuation in this location.
* Data strongly imply that natural attenuation is removing significant loadings of chlorinated
compounds and organic contaminants within some plumes in OU 5.
* Data from the OU 5 Wetlands project indicate that well 403-WL-01 has 66 ug/L of TCE. It is
recommended that this TCE plume be investigated and monitored in 2002. |
Louis Howard |
| 1/28/2002 |
Document, Report, or Work plan Review - other |
Staff commented on the Wetland Remediation System report. The text states the overall point of compliance for evaluation of cleanup levels is Ship Creek. The Alaska Water Quality Standards (AWQS 18 AAC 70) must be met in the surface water and the groundwater cleanup levels (18 AAC 75) need to be met in the groundwater. The AWQS apply to: The effluent from the wetland remediation system (WRS) and the groundwater, which emanates from the bluffs as seeps and is not captured and subsequently treated by the WRS.
Table 2-2 System Components Potentially Non-Protective of Human Health and the Environment Page 2-2: The text states groundwater at seeps 9, 10, and 11 are exceeding cleanup levels at the seeps. The potential exists for exceedance of cleanup levels at the point of compliance (Ship Creek). Again, it must be stressed that the Alaska Water Quality Standards must be met in all surface water and by not incorporating the seeps into the WRS, the Alaska Water Quality Standards are not being met.
The report’s recommendations are to continue monitoring at these seep locations, an upgradient soil gas investigation, and increased groundwater monitoring at upgradient monitoring wells. This temporary solution, if delayed beyond 2002, does not meet the ROD criteria that the selected remedy be protective of human health and the environment and utilize permanent solutions (see 5.1 Statutory Determination). Should the 2002 monitoring data for the seeps demonstrate contaminants remain above action levels, ADEC prefers seeps 9, 10 and 11 be incorporated into the WRS in a timely manner.
The ADEC recognizes that funding for incorporation of any additional seeps into the WRS is not likely to be available in the immediate future. Also, there is the issue of the Alaska Railroad’s expansion of its railroad yard, which may impinge upon the timing of incorporation of the new seeps into the WRS. Until the Railroad expansion work is completed, the ADEC is willing to continue to work with the EPA and AF on addressing Seeps 9, 10, and 11 in the most appropriate manner while continuing to be protective of human health and the environment.
2.2.2 Newly Identified Seeps Page 2-4
The text states the water from Seep 9 is mostly draining into the wetland cell; however some water appears to be bypassing the system and is flowing into the drainage that captures water originating from Seeps 10 and 11, thereby not being treated by the WRS. By allowing these seeps to continue to bypass the WRS, the Air Force is essentially choosing to implement the Alternative 1 “No Action” approach identified in the OU 5 ROD. This approach would not be as protective as incorporating the seeps into the WRS because people and environmental receptors would continue to be exposed to contaminants present in the groundwater seeps until it eventually degrades to acceptable levels. Continued monitoring of Seeps 9, 10 and 11 would not result in reduction in toxicity, mobility, and volume through active treatment.
See site file for additional information. |
Louis Howard |
| 2/21/2002 |
Document, Report, or Work plan Review - other |
Regulatory Levels
ADEC requests removing the word “Potential” from the heading “Potential Regulatory Level” in the tables throughout the document. Listing the word “Potential” gives the reader the impression that compliance with the levels listed is optional or not required (e.g. Tables 4-7, 4-11, 4-15, 4-20, 4-25, 4-29, 4-32, and 6-2).
Free Product
Please note 18 AAC 75.325(f) states: A responsible person shall to the maximum extent practicable ,
(A) use permanent remedies;
(B) recover free product in a manner that minimizes the spread of contamination into an uncontaminated area by using containment, recovery, and disposal techniques appropriate to site conditions.
ADEC recognizes that in some cases it may not be technically practicable to implement an active or passive recovery system for free product. The Elmendorf Remedial Action Report for Operable Unit (OU) 2 (September 1998) set a precedent for defining what is meant by “technically practicable” for free product recovery. Section 2.4.1 Product Recovery Endpoints at the 1st bullet on page 10 states: “As designed and constructed, the ST41 ground water treatment system cannot recover floating product when there is less than a measurable thickness of 0.1 feet of product. Therefore, as an endpoint for product recovery, if less than 0.1 feet is sustained for one year, recovery at that source can be discontinued. Floating product will be measured monthly. When product thickness falls below 0.1 feet for one year, the recovery of product at that source will not be considered “technically practicable”.
Therefore, where free product is greater than 0.10 feet, ADEC expects corrective action (active or passive) to be implemented for free product recovery. Currently, free product was found to exceed 0.10 feet or more in SERA Phase I well 43-WL-11. This well had the highest level of free product measured at 0.86 feet. The presence of measurable free product is generally not considered conducive for intrinsic (natural) attenuation. ADEC requests the identity of the free product be described in the text at each source area that it is found (e.g. gasoline, diesel, or chlorinated solvents).
3.3.4 Target Analytes Pages 3-10 and 3-11
Benzene and TCE are identified as target analytes to evaluate contaminant of concern (COC) trends in detail and be consistent with the Base wide Groundwater model. ADEC concurs, however, focusing on these two analytes does not accurately reflect whether diesel range organics (DRO) and gasoline range organics (GRO) plumes are migrating, expanding, steady state, or receding (especially for wells noted to have either free product or fuel odor and/or sheen being observed during sampling). Benzene can be at low levels or even non-detectable while concentrations of DRO and GRO remain above cleanup levels (1.5 mg/L and 1.3 mg/L respectively). Please see the following examples below of where benzene was below the 5 ug/L cleanup level, but DRO and GRO are above cleanup levels.
OU 4
Round 1 sampling at well 49-WL-01 detected benzene at 0.11 ug/L and DRO at 2,400 ug/L and well OU4W-11 detected benzene at 4.3 ug/L while GRO was detected at 3,000 ug/L and DRO was detected at 6,100 ug/L.
OU6
Round 1 sampling at well OU6MW67 detected benzene at 2.8 ug/L, GRO at 2,500 ug/L and DRO at 1,700 ug/L during round 1 sampling. During round 2 sampling, well OU6MW-91 detected GRO at 25,000 ug/L and DRO at 9,500 ug/L while benzene was found to be non-detectable.
See site file for additional information. |
Louis Howard |
| 4/30/2002 |
Update or Other Action |
Basewide Environmental Monitoring Plan received.
2.5 Soil Gas Survey
A Gore-sorber® survey and passive diffusion sampling was performed in December 2001 at four
wells in the OU 5 source area (403-MW-01, 700-WL-01, OU5MW-03, and SP2/6-01). Both the sorber
and PDBs results indicated that the extent of contaminated soil and/or groundwater was concentrated in the area surrounding 403-MW-01. To confirm the levels of contamination detected in December 2001 and further investigate the possible source, a select number of sorbers will be placed within the area of 403-MW-01. Additional sorbers will be installed around Building 4314, the most likely source of the chlorinated hydrocarbon contamination detected during the December 2001 investigation. Following analysis of the Gore-sorber®, up to two monitoring wells will be installed as step-out locations from areas with highest elevated detections during the soil-gas survey to further define extent of contamination and monitor migration.
A4.3 Passive Diffusion Bag Sampler Procedures
In an effort to optimize the 2002 Basewide Program, 16 wells will be added to the OU 5 source
area to help serve as an early warning system for Ship Creek (Figure A4-4). These wells will be sampled for VOCs only, using a PDB.
The typical PDB consists of a low-density polyethylene lay-flat tube closed at both ends and is
filled with analyte-free deionized water. The PBD membrane acts as a semi-permeable membrane to
certain contaminants, especially specifically chlorinated VOCs. VOCs in the groundwater diffuse across the membrane into the deionized water in the bag until equilibrium is established between the diffusible VOC in the groundwater and in the deionized water.
PDB bags will be placed in the wells approximately 1 foot from the screen and will be attached
with a nylon string to the top of the well casings. The PDBs will be left in the wells for approximately two weeks and at that time will be removed and used to fill VOC sampling bottles. The bottles will then be handled and analyzed as outlined in Section A4.5. Field parameters will not be taken as part of the analysis for PDB samples
A7.1 Site History
In December 2001 preliminary sampling was done at OU 5 in an effort to identify the source for
trichloroethene (TCE) exceedances at seeps 9, 10, and 11 within the Elmendorf OU 5 Wetlands Program. PDBs and Gore-sorber® soil gas probes were inserted into four wells upgradient of the seeps. TCE was detected above the MCL in only one well, 403-MW-01. The PDBs measured TCE at 66 micrograms per liter (pLg/L) and the Gore-sorbers® reported the TCE level at 65.68 tg per sorber. TCE was detected at OU5MW-03 but was below reporting limits.
Research into the area revealed a possible contaminant source as the former Diesel Maintaince
Shop, Building number 5332. As a maintaince shop, this building was closed in March 1995. Today this building is used as the Explosive Ordnance Building (EOD). During the 2002 field season Gore-sorbers® will be placed in the areas surrounding and between the former Diesel Maintaince Shop (Building 5332) and the TSD/Hazardous Storage Building (Building 4314) (Figure A7-1). This investigation will help pinpoint the source and the deliniation of the plume associated with Well 403-MW-01. |
Louis Howard |
| 6/7/2002 |
Update or Other Action |
In 2002, seven monitoring wells were sampled for VOCs using a semi-permeable membrane device called a PDB. Further information regarding the PDB is provided in the Basewide Environmental Monitoring Plan (2002). These wells were sampled semi-annually in 2002, with the first event occurring on June 7, 2002, and the second on August 31, 2002. |
Louis Howard |
| 6/28/2002 |
Update or Other Action |
Final work plan for Basewide Environmental Monitoring Plan received dated June 2002. 2.3.4.2 Program Area Modifications in 2002: All of the wells will remain for the 2002 OU 5 sampling scheme. Five wells, 403-MW-01 OU5MW-15, 61-WL-01, 61-WL-02, & ST20-MW-11 will be added to aid in monitoring & characterization of trichloroethene (TCE) plumes. Nine more wells will be added to improve the monitoring well network used as the early warning system for contaminant migration toward Ship Creek.
All of the wells are located upgradient of Ship Creek at a distance that will give approximately two years of advanced warning of new or increased contamination moving in the direction of this environmental receptor. In addition, two analytes, TOC & dissolved gases, will be added to the OU 5 suite of analytes in wells associated with chlorinated solvent contamination to better monitor natural attenuation in this program area.
GRO & DRO were added to the analyte suite at several wells in OU 5 at the request of the ADEC. All wells included in the early warning well network will be sampled for VOCs only using passive diffusion sample bags as outlined in the FSP in Section A4.3.
A4.1.4 Operable Unit 5: Twenty-eight monitoring wells are included in the long-term monitoring program for OU 5. Twelve of these wells will be sampled to track known contaminant plumes & will provide data necessary to track natural attenuation as a part of the OU 5 source area. The remaining 16 wells will be sampled as a part of the Ship Creek early warning system. The locations of these wells are provided in Figure A4-4. The OU 5 source area wells & the 13 early warning wells will be sampled biannually in 2002, with events scheduled during the months of May & July. The 3 wells, upgradient of OU5MW-07 which will be used to provide additional data for the early warning network, will be sampled once. A detailed field schedule for this program is provided in Section 4 of the EMP. All wells will be sampled according to the procedures outlined in this FSP.
All of the wells in the traditional OU 5 sampling program are affixed with dedicated sampling devices, & will be sampled accordingly via low-flow sampling techniques outlined in Section A4.2.1. The additional early warning wells will be also be sampled according to the procedures outlined in this FSP. These wells will be sampled according to the technique outlined in Section A4.3 using passive diffusion bags (PDBs). These OU 5 GW samples collected will be analyzed according to the methods outlined in Table A-4. Well purging & field analysis, however, will not be performed on wells sampled with PDBs. Details on the requirements for sample holding times & preservation, & the applicable QA/QC sample requirements, are provided in Appendix C of the EMP.
Passive Diffusion Bag Sampler Procedures: In an effort to optimize the 2002 Basewide Program, 16 wells will be added to the OU 5 source area to help serve as an early warning system for Ship Creek (Figure A4-4). These wells will be sampled for VOCs only, using a PDB.
PDB bags will be placed in the wells approximately 1 foot from the screen & will be attached with a nylon string to the top of the well casings. The PDBs will be left in the wells for approximately two weeks & at that time will be removed & used to fill VOC sampling bottles. The bottles will then be handled & analyzed as outlined in Section A4.5. Field parameters will not be taken as part of the analysis for PDB samples.
During the 2001 field season, the OU 5 Wetlands program identified TCE above ADEC cleanup levels at Seeps 9, 10, & 11. A limited field investigation indicated that GW had been impacted with TCE at Well 403-MW-0 1; however, the nature & extent were not identified. An additional investigation to delineate both the horizontal & vertical extents of contamination will take place this season. This investigation will include, but is not limited to, a soil gas survey, additional soil borings, subsurface soil sampling, & monitoring well installation.
Also during the 2001 field season, a similar investigation will occur in the Dallas Housing Area. This limited investigation will help delineate the nature & extent of the plume associated with Wells 48-WL-03, 49-WI-01, & OU3MW-11 in OU 4 & OU 5. As with 403-MW-01, this investigation will include, but is not limited to, a soil gas survey, additional soil borings, subsurface soil sampling, & monitoring well installation. |
Louis Howard |
| 7/28/2002 |
Enforcement Agreement or Order |
ADEC (CS Program S. Bainbridge, Leslie Pearson PER Program) and Air Force (Daniel Barnett) signed the Operational Agreement (OA) concerning presumptive remedies for cleanup of certain petroleum oil and lubricant releases on the outwash plain portion of Elmendorf AFB, Alaska. This OA establishes and describes pre-approved presumptive remedies but does not establish an exclusive set of cleanup options and nothing in the memorandum prohibits EAFB from seeking or obtaining ADEC approval to implement alternative release response and remedial action plans.
For new POL spills in the outwash plain that occur in areas with no operational restrictions or interference from surrounding structures, ADEC approves immediate remediation of contaminated media after free product has been recovered in a manner that minimizes the spread of contamination into an uncontaminated area by using containment, recovery, disposal techniques appropriate to site conditions. The presumptive remedy for new POL spills on the outwash plain consist of excavation, treatment, and disposal of all impacted soil.
On a case-by-case basis, ADEC will evaluated the need for recovery of free product from the water table. Finally groundwater monitoring and ICs placed on the shallow aquifer restricting its use as a drinking water source will be required until such a time that the appropriate groundwater remedial goals are met. If additional institutional controls are required, these controls will be developed by EAFB in consultation with ADEC.
The OA does not apply to spills impacting surface waters. Nothing in the OA relieves, extends or changes the applicable requirements of 18 AAC 75 and 78 for the proper treatment, storage or disposal of contaminated media that result from the implementation of this OA.
Note to file: Monitoring objectives for the Early Warning Line are as follows: Track chlorinated contaminants of concern concentrations in groundwater and detect any contamination above Operable Unit 5 ROD specific cleanup levels. The Record of Decision for OU 5 states: Chemical specific applicable or relevant and appropriate requirements for groundwater are trichloroethene at 5 ug/L, benzene at 5 ug/L, TFH Diesel 10 ug/L and TFH Gas at 10 ug/L. The ROD specified cleanup levels for TFH-diesel and TFH-gas were conceptually modified in 1998 to include TAH and TAqH. Because there was no standard for TFH-diesel and
TFH-gas in groundwater, and because the groundwater
emerges as surface water at the seeps that eventually flow
into Ship Creek (an aquaculture resource), the Alaska Water
Quality Standards, aquaculture standards, for TAH and
TAqH were used. (18 AAC 70.020, based on ecological
risk). |
Steve Bainbridge |
| 8/28/2002 |
Meeting or Teleconference Held |
STATUS MEETING MINUTES ELMENDORF BASEWIDE MONITORING PROGRAM, Attendees: Joe Williamson (USAF), Cindy Hood (AFCEE), Terry Beach (AFCEE), Kevin Oates (EPA), Louis Howard (ADEC), Cory Hinds (URS), Russ Beck(URS)
Agenda: • Review of soil gas surveys and new well locations; • Recommendation for treatment of TCE at OU5 Seeps 9, 10, and 11 in the existing Wetland Remediation System; • Well sampling frequencies for 2003
OU5: Seeps 9, 10, and 11-A report titled Draft Technical Memorandum Trichlorethene Collection and Treatment Alternatives Operable Unit 5 Engineered Wetland Remediation System was summarized and discussed. The report concluded that the best (technically appropriate, least cost, fastest) method of treating the TCE in Seeps 9, 10, and 11 is to divert these seeps into the adjacent Wetland Cell. TCE is degraded via phytoremediation (breakdown and synthesis by plants).
Diversion of the seeps could take place as early as 2004. The Air Force needs to make sure that the seeps are on the EAFB easement. Design will need to take place in 2003. Diversion of the seeps will also be based on upgradient water quality. New data upgradient of the seeps will be provided by the installation of two new wells (OU5MW-35 and –36) in 2002. The decision on whether to proceed with seep diversion will be based on all available data and will be made in October, 2002.
EPA felt this was a fair assessment, but wanted to know what would happen if increasing concentrations of TCE were found upgradient of the seeps. AF will use the OU 5 Wetlands decision guide [Decision Process for Increased Remedial Activity, Figure 5-2, 2001 Annual Technical Report Operable Unit 5], which may need to be revised. It was agreed that the decision guide should be modified so that seeps are collected if there is evidence of a continued source or increasing COC concentrations.
The diversion of seeps will require excavation of soil/sediment that may be contaminated. Air Force may need to treat excavated soil from the project off-site because landfarming of contaminated soil, as outlined in the OU 5 ROD, is no longer an option on EAFB. This change will require an Explanation of Significant Differences (ESD). If the Air Force will keep a list of things that differ from the ROD, the EPA would be able to direct them as to which of these need an ESD. Both ADEC and EPA are comfortable with the Air Force approach to dealing with the seeps.
NOTE TO FILE: When documenting significant changes made to a remedy, the lead agency must comply with CERCLA §117(c) and NCP §§300.435(c)(2)(i) and 300.825(a)(2). An ESD must describe to the public the nature of the significant changes, summarize the information that led to making the changes, and affirm that the revised remedy complies with the NCP and the statutory requirements of CERCLA.
2003 Monitoring Well Sampling Frequencies- URS presented the new proposed Basewide decision guide for determining sampling frequencies for monitoring wells. Proposed monitoring frequencies are based on position of plumes relative to environmental receptors. Plumes immediately upgradient of a receptor were proposed for annual sampling. Plume not immediately upgradient of a receptor were proposed for sampling every 2 to 5 years.
EPA pointed out that this guide is only appropriate for stable plumes and suggested that we add a box to include a decision for unstable plumes. Unstable plumes should be sampled semi-annually if upgradient of a receptor or within the early warning line in OU 5.
URS presented the new sampling frequency table, which is based on plumes rather than program areas. EPA and ADEC agree that it makes sense to organize on a plume-by-plume basis instead of by program area. The Air Force mentioned that there will be additional wells required for the early warning system at OU5, and that some of the early warning sampling will be conducted using passive diffusion bags. Use of the passive bags may mean that it is feasible to sample in the winter. EPA, ADEC, and URS agreed on modification of sampling frequencies. In general, sampling frequencies were increased when the plumes were close to a receptor (i.e., Ship Creek) or the concentrations of contaminants were increasing. A list of the agreed sampling frequencies is attached.
Additional items discussed:
• WP14: Air Force mentions reducing number of wells. ADEC mentions an early warning system. These will be discussed later.
• Air Force will investigate the floating product at OU4 West. |
Louis Howard |
| 11/18/2002 |
Document, Report, or Work plan Review - other |
Review and comment on draft Institutional Controls Management Plan dated October 2002.
1.2.2 Environmental Restoration Program Page 1-2
The text states that no ICs are associated with the SERA program. The Department requests the Air Force clarify how it will implement and manage ICs at sites not in the CERCLA program, such as those sites in the environmental restoration and compliance programs, where ICs would normally be required. For example, sites requiring ICs would include those sites where long term groundwater or surface water monitoring is being conducted, or sites where monitored natural attenuation (MNA) is being considered/been established, or where alternative cleanup levels are being considered or have been established.
The Department is in receipt of a compliance program document which identifies several compliance sites where MNA was identified as a remedy. In order for MNA to be accepted by the Department for any site, it will require that ICs be in place and enforceable on the impacted soils and/or groundwater until cleanup levels have been achieved.
Additionally, preliminary data results for ST 401 investigation was obtained during a project manager meeting held on November 12, 2002. The data shows that groundwater results from two monitoring wells located upgradient of two groundwater seeps are contaminated with diesel range organics (DRO) above cleanup levels. Specifically, wells 401-WL-03 and 401-WL-04 had 38.6 mg/L and 13.2 mg/L DRO detected in the groundwater.
Residual range organics (RRO) results could not be conclusively ruled out for well 401-WL-03 since the detection limit was above the Table C cleanup level. In view of this new data, the Department will require continued monitoring in the OU5 area for DRO and RRO in addition to the other petroleum constituents that are being monitored.
If monitoring for petroleum fuel range constituents will not be conducted under CERCLA as a part of the base wide program, then the Department will require groundwater monitoring be conducted under environmental restoration/compliance programs as required by 18 AAC 75 Contaminated Sites regulations (see 18 AAC 75.335 Site Characterization, 18 AAC 75.345(g-j)) and 18 AAC 78 Underground Storage Tank regulations (see 18 AAC 78.235 Release Investigation and 18 AAC 78.615 Groundwater and Surface Water Sample Number and Location). |
Louis Howard |
| 12/27/2002 |
Document, Report, or Work plan Review - other |
Staff reviewed and commented on the Five year review for the OU5 Wetland remediation system. The text states this is the first five-year review for the operable unit (OU) 5 Wetland Remediation System (WRS). The Department disagrees. The OU 5 Remedial Action Report and 1998 Five Year Review have both mentioned and addressed the OU 5 WRS. This may be the first OU 5 WRS “specific” five-year review but not the first time the OU 5 WRS was reviewed.
2.0 Description, Background and Current Status Page 1: The text states the OU 5 WRS and Beaver Pond treat contaminated groundwater from OU 5. The Department wishes to expand on this particular statement since it is not entirely true. The Department requests the Air Force include the following information that was mentioned in the 1998 five-year review, but is now absent in this document.
Approximately 90 percent of the shallow aquifer flowing through Elmendorf Air Force Base (AFB) is believed to flow into OU 5. Upgradient sources from OU 5 are the source of some of the groundwater contamination in OU5. These sources include, but are not limited to, OUs 1, 2, 4 and several petroleum source areas which include contaminants such as: gasoline range organics (GRO), diesel range organics (DRO), residual range organics (RRO) and BTEX (benzene, ethylbenzene, toluene, and total xylenes). Regardless of the source, the majority of the groundwater from the shallow aquifer is being treated through the OU 5 WRS.
3.2 Remedy Implementation Page 2: The text states that the Base wide program was established to ensure that both OU-specific and base wide groundwater issues are addressed and the majority of the shallow aquifer discharges into wetlands adjacent to Ship Creek. While DRO, GRO, and RRO, are not specifically included in the OU 5 ROD as specific action levels, the Air Force cannot ignore their presence in the shallow aquifer and therefore not monitor for them in the area known as OU 5. As stated in the Department’s letter commenting on the Draft Institutional Controls Management Plan, preliminary data for the ST 401 investigation shows the presence of DRO above 18 AAC 75 Table C groundwater cleanup level for DRO. The two monitoring wells located upgradient, but in close proximity, of two groundwater seeps at the OU 5 bluff area were shown to have 38.6 mg/L and 13.2 mg/L of DRO contamination present in the groundwater.
If monitoring for petroleum fuel range constituents will not be conducted under CERCLA as a part of the base wide program, then the Department will require groundwater monitoring in OU 5 be conducted separately under environmental restoration/compliance programs as required by 18 AAC 75 Contaminated Sites regulations (see 18 AAC 75.335 Site Characterization, 18 AAC 75.345(g-j)) and 18 AAC 78 Underground Storage Tank regulations (see 18 AAC 78.235 Release Investigation and 18 AAC 78.615 Groundwater and Surface Water Sample Number and Location). How this issue gets resolved either in the five year review or as an added monitoring requirement under the Air Force restoration/compliance program is up for discussion.
4.0 Technical Assessment Question B Page 4: The text states that no other exposure assumptions, toxicity data, cleanup levels or remedial action objectives have changed since the time of the remedy selection. The Department disagrees. The State of Alaska has promulgated in regulation, cleanup levels for: DRO, GRO, and RRO contamination in groundwater and surface water. Specifically, 18 AAC 75.345 “Groundwater and Surface Water Cleanup Levels.” states: (a) Except as otherwise provided in this section, cleanup of a discharge or release of a hazardous substance to groundwater or surface water must meet the requirements of this section. This section includes Table C which identifies the following cleanup levels: DRO-1.5 mg/L, GRO-1.3 mg/L, and RRO-1.1 mg/L. |
Louis Howard |
| 1/14/2003 |
Meeting or Teleconference Held |
Meeting minutes from January 14, 2003 meeting with Joe Williamson (USAF), Gary Fink (USAF), James Klasen (USAF), Kevin Oates (EPA), Louis Howard (ADEC), Cory Hinds (URS), Paul Dworian (URS), Kristin Paul (URS)
Discuss ADEC’s request to add the analyses of Diesel Range Organics (DRO) and Gasoline Range Organics (GRO) to several Operable Units at Elmendorf.
1. URS summarized recent (year 2000) ADEC risk assessment guidance that shows that DRO and GRO themselves can cause noncarcinogenic human health risks. This information was not known during preparation of the risk assessments and RODs for Elmendorf Operable Units. Therefore, addition of DRO/GRO to the sampling scheme for Elmendorf was recommended.
2. The Air Force agreed to add DRO/GRO, but cannot add funding to cover the additional analysis until 2004.
3. The following was decided on implementation:
A. This decision will be documented in the 5-Year Review. The addition of DRO/GRO to the program should be introduced in the 5-Year Review under mention of new issues affecting protectiveness.
B. The Air Force will NOT add DRO/GRO as a CERCLA ARAR, but will compare DRO/GRO results to ADEC cleanup levels in the annual reports and will discuss in subsequent 5-Year Reviews. The benefit of this is that if CERCLA COCs meet ARARs, the Air Force can achieve a partial delisting.
C. The Air Force will add DRO and GRO to the suite of analyses at monitoring wells associated with fuel plumes starting in 2004.
D. The Air Force will not pursue a decision document with ADEC on DRO/GRO until more data is gathered on the extent of the problem.
E. Until a decision document is signed with ADEC, GRO and DRO concentrations will be compared to ADEC regulations in 18 AAC 75 (Table C, Groundwater Cleanup Levels; 1,500 µg/L for DRO, 1,300 µg/L GRO).
F. Sampling frequency for DRO/GRO will follow the latest Decision Guide for Sampling Frequency (see 2002 Basewide Annual Report). “Immediately upgradient” means within a 2-year warning line, similar to that generated for OU5.
G. ADEC GRO/DRO criteria apply to groundwater, not to seeps which daylight as surface water. Criteria in 18 AAC 70 (TAH, TaqH) apply to surface water. |
Louis Howard |
| 1/31/2003 |
Update or Other Action |
2002 Annual Report Basewide Environmental Monitoring Program Draft January 2003 received.
Program Areas Operational changes were made through the use of Passive Diffusion Bags (PDBs) in 16 OU 5 Early Warning wells & in five OU 2 wells as a part of the 2002 Basewide Program. The use of PDBs reduced the amount of purge water associated with normal pump sampling, eliminated the need for equipment decontamination & equipment blank sampling at these locations, & reduced the amount of time required for sampling & parameter stabilization.
The following wells were added to the OU 5 semiannual program & were sampled for VOCs only using PDBs: 61-WL-01, 61-WL-02, 76-WL-01, 403-MW-01, 1836-WL-01, OU3MW-04, OU3MW-16, OU5MW-01, OU5MW-05, OU5MW-11, SP4/11-03, & ST20-MW-11.
These wells were added to the Basewide Program to serve as an early warning system for Ship Creek, an environmental receptor. PDBs, which are used to monitor specifically for VOCs, were used to provide information on the target analytes TCE & benzene.
Early Warning Wells
In 2002, seven monitoring wells were sampled for VOCs using a semi-permeable membrane device called a PDB. Further information regarding the PDB is provided in the Basewide Environmental
Monitoring Plan (USAF, 2002d). These wells are shown on Plate 1 & listed in Table 1-5. These wells were sampled semi-annually in 2002, with the first event occurring on June 7, 2002, & the second on August 31, 2002.
Six of the seven wells sampled as part of this system were below cleanup levels for TCE for both rounds during 2002. One well had concentrations above cleanup levels for both rounds; Well 1836-WL-01 had 14 µg/L TCE in Round 1 & 17 µg/L TCE in Round 2 as seen in Table 3-6. Further
discussion of this well is provided in Section 3.4.2.2.6 Slammer Ave. Plume. In summary, sampling upgradient of the Early Warning Wells in 2002 did not identify any contaminant plumes that pose an imminent threat to Ship Creek. It is recommended that PDB sampling for VOCs continue on an annual basis at all wells in the 2002 OU 5 Early Warning System. This relatively inexpensive method of monitoring will help to provide warning of any unsuspected contaminant migration toward Ship Creek.
Sentry Wells
Sentry wells are wells located upgradient of environmental receptors (Table 1-5), but within
(downgradient of) the Early Warning Line. These wells are critical for monitoring contaminant plumes that extend toward receptors like Ship Creek. These wells are also sampled using PDBs.
A total of eight sentry wells are monitored in OU 5. Year 2002 data showed no evidence of increasing GW contamination at any location within the sentry well network.
It is recommended that two additional sample locations, Wells OU5GW-42 and OU5GW-44 located southeast of Beaver Pond, be sampled with PDBs in 2003 to determine the downgradient extent of the eastern margin of the Slammer Ave. Plume.
Note to file under:
ARARs
This data-reporting category addresses GW constituents for each individual program area
specifically identified as COCs. The original list of cleanup levels for each program area is listed in Table 2-1. These chemical-specific cleanup levels were identified either in decision documents prepared for these sites (FFA program areas) or as contaminants which were found to significantly exceed cleanup levels where GW COCs were not specifically identified in previous investigations (SERA & Taxiway “N” program areas). Source documents that listed cleanup levels are referenced in Section 4.
Within the context of the Basewide Program, the list of COCs for each program area can change as data are continuously evaluated & the quality of data improves with new methods. For instance, as natural attenuation occurs, select constituents will reach cleanup levels & additional monitoring for that constituent will not be required unless mandated by a regulatory agreement. Specifically, if a COC is below cleanup levels for two consecutive sampling rounds, sampling for that COC can be discontinued.
Similarly, if cleanup levels for all COCs in a given analytical method are met across an entire program area, analysis using that method in that program area will no longer be required. An exception to the above guideline is made for OU 5. Because OU 5 serves as the downgradient receptor for most of the other program areas, COCs will NOT be eliminated from OU 5 unless the COC in question has been similarly eliminated first from all upgradient program areas. |
Louis Howard |
| 6/11/2003 |
Meeting or Teleconference Held |
MEMORANDUM FOR FILE FROM: 3 CES/CEVR SUBJECT: Minutes, Remedial Project Manager Meeting, 11 June 2003
A quarterly meeting of the remedial project managers (RPMs) convened at 1430 on 11 Jun 03 in the Environmental Flight (CEVR) conference room, Building 5312. Mr. Louis Howard (Alaska Department of Environmental Conservation (ADEC), Mr. Kevin Oates (Environmental Protection Agency (EPA) - Anchorage), Mr. Gary Fink (CEVR), Mr. Joe Williamson (CEVR), Ms. Donna Baumler (CEVR), and Ms. Doris Thomas (Public Affairs (3WG/PA) attended. Mr. Claude Mayer (CEVR) joined the meeting via teleconference. Mr. Jim Klasen (Legal (11AF/JACE) was attending a training course and was unable to attend.
DP98, Land Use Control Issues (Ms. Baumler). Ms. Baumler stated that the Land Use Control (LUC} Management Action Plan (MAP) was completed in January. It has been updated to include information for DP98. A signature page for the Environmental Protection Committee (EPC) Chairman also has been added. In the future, we plan to have a wing instruction to assist in the enforcement of the MAP. Ms Baumler provided copies of the DP98 inserts which incorporate Mr. Howard's review comments regarding continuous implementation of institutional controls. The MAP will go to the EPC Chairman for signature and should be ready for distribution by the end of the month.
DP98, 2 Jul Meeting for Proposed Plan (Mr Mayer). Mr Mayer stated that the proposed 2 Jul date
would coincide with the date comments were due from agencies and would provide an opportunity to
meet with the contractor to resolve any issues.
Mr. Oates commented that the date would work with his schedule and reminded us that he would be gone in 31 days. He agreed that the meeting would be beneficial. Mr. Oates made a few remarks about the Proposed Plan. He said some new issues have arisen in the last few years, such as groundwater analysis of 1,4-Dioxane. This chemical was sometimes used as a stabilizer for different types of ethenes. Mr. Howard stated that detection requires a different method of analysis from the type we currently use.
Mr. Williamson said that we would add the new analysis to the Basewide Groundwater Monitoring Program next year. |
Louis Howard |
| 6/11/2003 |
Meeting or Teleconference Held |
MEMORANDUM FOR FILE FROM: 3 CES/CEVR SUBJECT: Minutes, Remedial Project Manager Meeting, 11 June 2003
A quarterly meeting of the remedial project managers (RPMs) convened at 1430L on 11 Jun
03 in the Environmental Flight (CEVR) conference room, Building 5312. Mr Louis Howard
(Alaska Department of Environmental Conservation (ADEC», Mr Kevin Oates (Environmental
Protection Agency (EPA) - Anchorage), Mr Gary Fink (CEVR), Mr Joe Williamson (CEVR),
Ms Donna Baumler (CEVR), and Ms Doris Thomas (Public Affairs (3WG/PA» attended. Mr
Claude Mayer (CEVR) joined the meeting via teleconference. Mr Jim Klasen (Legal
(11AF/JACE) was attending a training course and was unable to attend.
Five-Year Review, Evaluating New Standards (Mr Fink). To illustrate his question, Mr Fink used
1, 1,2,2-PCA as an example. When the ROD was signed, there was no Maximum Contaminant Level
(MCL) for 1,1,2,2-PCA, but now there is. The Alaska Railroad CARR) is concerned about upgradient
wells. Research indicates that there is no 1, 1,2,2-PCA upgradient; however, there is some in the area of the Beaver Pond. Mr Fink looked through the Remedial Investigation/Feasibility Study (RI/FS), especially at the risk assessment, and thinks we should be able to use the same assumptions. He reasoned that if we use the same assumptions as in the original risk assessment and we remain under MCL, then the original risk assessments would still be current. Mr Oates suggested using today's risk assessment with the original assumptions and told us how to find a risk assessment calculator on the ADEC web page, He also said we could use the calculator to run all of our risk assessments and add them to the Five-Year Review as an appendix. Mr Oates said that a complete risk assessment is not necessary for the purpose of the Five-Year Review. |
Louis Howard |
| 9/25/2003 |
Update or Other Action |
Memorandum to site file signed September 19, 2003 by AF, EPA and ADEC establishing the groundwater sampling frequency decision guide. The purpose of this document (Memorandum to the Site File) is to present non-significant or minor changes to the Record of Decision (ROD) signed for OU 5 at EAFB. The minor changes to the OU 5 ROD involve modifying the sampling frequency of groundwater wells. Other components to the OU 5 selected remedy will not be affected by this minor change.
This minor revision to the ROD changes the sampling frequency for groundwater monitoring.
Data collected semi-annually over the past seven years has provided an understanding of the
nature and extent of contaminant migration and the effectiveness of intrinsic (natural)
remediation. In many instances continuation of the semi-annual sampling would not provide any
useful new data as compared to less frequent monitoring.
Revised Remedy: Sampling for groundwater will be changed from semi-annually to a frequency determined by the Decision Guide. The changes to the sampling frequency will continue to provide sufficient data to assess contaminant migration and timely reduction of contaminant concentrations by intrinsic remediation as required by the ROD. The revised monitoring frequency will also streamline the groundwater reporting process and reduce monitoring costs.
These changes to the sampling frequencies were discussed in the August 28, 2002 meeting
between the USAF, Region X of the EPA and the State of ADEC. Both EPA and ADEC project managers concurred with the proposed changes. This change in the ROD does not significantly change or fundamentally affect the remedy selected in the ROD; therefore, no public comment is required. |
Louis Howard |
| 10/1/2003 |
Update or Other Action |
The Basewide Groundwater Monitoring Plan received. The BW GW Monitoring Program (herein called "the Program") was established through the Elmendorf Air Force Base (herein "the Base") Installation Restoration Program to address the needs of multiple programs on the Base. These programs include the Federal Facilities Agreement (FFA) and the State-Elmendorf Environmental Restoration Agreement (formerly "SERA"; now known as "State Program Sites".)
In response to the findings of the Records of Decisions (RODs) for each program area, the
United States Air Force began annual groundwater monitoring. This Basewide Groundwater
Monitoring Plan ("the Plan") presents relevant historical direction and methodologies of the
Program in addition to background information on individual program areas. A generalized
approach to groundwater monitoring practices for the Program is also provided in this Plan. A
yearly Program Activities Addenda, detailing specific activities to be performed, will be
submitted annually.
The purpose of long-term groundwater monitoring at OU 5 is to monitor the rate of natural
attenuation, provide early warning of potential off-site contaminant migration that could affect
the operation of the OU 5 Wetland Remediation System (WRS), and to provide long-term
monitoring to ensure contamination is not threatening Ship Creek.
The Kenney Avenue Plume lies in the central portion of the OU 5 program area at the
intersection of Kenney Avenue and 5th Street. The plume outline resembles a triangular shape
that spreads as it proceeds with local groundwater flow about 600 feet south of Building 5332.
Vertically, the plume occupies the shallow unconfined aquifer, which is underlain by the
Bootlegger Cove Formation aquitard. The aquifer averages approximately 25 feet thick in this
region of OU 5.
Natural attenuation of TCE in this plume is very limited. The limits appear to be due to a lack of carbon in the aquifer. Due to biodegradation rates and proximity to receptors, natural attenuation within the aquifer by itself is not a feasible remedy for the Kenney Avenue Plume. Contaminant migration off Elmendorf property is occurring. However, with the capture of additional seeps by the OU 5 WRS that is planned for 2004, treatment will occur and discharge from the WRS will remain below cleanup levels.
Future remedial activities at the Kenney Avenue Plume should focus on delineating the southern
boundary of this plume, characterizing its vertical profile, locating its source, implementing
annual natural attenuation monitoring, and sampling seeps on the bluff above Ship Creek.
The Slammer Avenue Plume is located in the eastern portion of OU 5 near the comer of
Slammer Avenue and Arctic Warrior Drive. The downgradient Beaver Pond captures a majority
of groundwater that migrates from this plume. Vertically, the plume occupies the shallow
unconfined aquifer and is underlain by the Bootlegger Cove Formation. The saturated zone in
this part of the outwash plain ranges from 10 feet thick near Ship Creek to 50 feet thick at the
upgradient margin of the plume. The source for this plume is unknown. The majority of field investigations in this area of the Base were performed in order to delineate fuel contamination
and did not explore the source of this chlorinated solvent plume.
This plume was originally regarded as a collection of several smaller plumes until it was
consolidated and viewed as one plume. The Slammer Plume is now portrayed as a rectangular
plume that is roughly 1,300 feet by 1,000 feet in dimension.
Natural attenuation monitoring performed on the Slammer Avenue Plume indicates that
chlorinated solvents are not breaking down at high rates. Though this is the case, contaminant
concentrations are low and decreasing. Current and historical data do not indicate the presence
of any large slugs of TCE moving downgradient to this location from an upgradient source. It is
unclear if TCE will decrease to below the cleanup level by 2010 as predicted in the OU 5 model.
For these reasons, future remedial activities at the Slammer Avenue Plume should focus on
delineating the southern boundary of this plume by installing downgradient sentinel wells near
Ship Creek and enhancing the level of natural attenuation monitoring to determine if closure will be achieved by the ROD specified date. |
Louis Howard |
| 11/13/2003 |
Update or Other Action |
TECHNICAL MEMORANDUM TO: Joseph Williamson (USAF, 3 CES/CEVR) FROM: Cory Hinds and Kristin Paul (URS Corporation) File 74-FAF00015 (URS Corporation) DATE: 13 November 2001 SUBJECT:Work Plan for TCE Groundwater Investigation at OU5.
The Air Force has requested that URS further investigate the presence of trichloroethylene (TCE) in the OU5 Wetlands area through the sampling of upgradient groundwater wells. TCE was found in the seeps at the base of the bluff area southwest of the U.S. Corps of Engineers (USCOE) building on Elmendorf Air Force Base.
A method employing the use of a water-filled passive diffusion bag (PDB) will be used in this investigation. The PDB samplers typically consist of a 1- to 2-ft long low-density polyethylene (LDPE) lay-flat tube closed at both ends. The samplers contain deionized water enclosed in a LDPE sleeve and are deployed adjacent to a target horizon within a screened or open interval of a well. The amount of time the PDB should be left in the well depends on the time required for the sampler to equilibrate with the well water, contaminant distribution, and flow dynamics. Laboratory and field data suggests a period no less than 2 weeks. At the end of the sampling period the bags are to be removed and the water placed in sampling vials for analysis.
In order to determine the extent of contamination, a PDB will be used to investigate groundwater quality upgradient from the seeps. The samplers will be placed in the following upgradient wells; OU5MW-3, 403-MW-01, SP2/6-01, and 700-WL-01. A PDB will be placed in each well and will remain for a period of 14 days. These PDB’s will be weighted and placed approximately 1 foot above the bottom of the screened interval to maximize possible TCE intake. On the 14th day each bag will be removed and the water retained from them will be immediately transferred to 40-milliliter sampling vials for analysis. |
Louis Howard |
| 12/5/2003 |
Document, Report, or Work plan Review - other |
Compliance Funded Contaminated Sites Review and Response Letter (which includes ST521): Residual soil and/or groundwater contamination is present at all of the sites. Based on our
review, thirty-six (36) of the sites (see the list below) do not appear to pose an unacceptable
risk to human health or the environment and are suitable for a No Further Remedial Action
Planned (NFRAP) determination.
The ADEC's NFRAP determination indicates that no additional cleanup is necessary but that institutional controls and/or long term monitoring are necessary. We have determined that the groundwater impacts at these sites are being adequately addressed within the base-wide groundwater monitoring program and the Operable Unit (OU)5 groundwater treatment system.
Because petroleum contaminated soil (contaminant levels higher than the Method 2 cleanup levels in Tables Bl/B2 found in 18 AAC 75.341) remains at these sites, the Base Master Plan needs to be updated to document the locations of residual contamination and the need to manage contaminated soil properly during any future construction or excavation work. Upon notification that the Base Master Plan has been updated, the ADEC will change the status of these sites in our contaminated sites database to NFRAP with institutional controls in place.
The following 36 sites eligible for NFRAP (ignoring the ST portion of the title): 404, 502, 517, 535, 405, 503, 518, 536, 411, 504, 519, 537, 413, 505/9, 520, 700, 414, 511, 521, 701, 415, 512, 525, 902, 430/9, 513, 528, 903, 431, 514, 530, 904, 501, 515, 533, and 906. |
John Halverson |
| 1/27/2004 |
CERCLA ROD Periodic Review |
The second five year review was signed by ADEC. The purpose of this five-year review is to evaluate the implementation and performance of the remedial actions that were selected in the Record of Decision (ROD) for each Operable Unit (OU). Annual sediment sampling at ST37 in OU5 has been conducted annually since 1997 and none of the sediment samples have contained fuel constituents (i.e. TFH-diesel, BTEX and PAH) at concentrations above State regulatory cleanup levels. Sediment results collected to date are sufficient to demonstrate that significant levels of COCs are not accumulating in the sediment in the Wetland Cell or Beaver Pond; therefore, sediment monitoring at ST37 should be discontinued.
The site inspection and interview conducted on February 11, 2003 revealed that LUCs and monitoring wells at OU5 appear to be adequate; monitoring seep sampling pipes and wells were in good working condition, properly located and locked; the WRS system, overland flow cell, pipes, pumps, and associated controls appeared to be in good working order, and spare parts were readily available. The influent, effluent, seeps and wells are routinely sampled, monitoring data is submitted on time and is of acceptable quality.
Because Alaska Water Quality Standards no longer specify the analytical methods TFH-Diesel
and TFH-Gas, a minor change was made to the hydrocarbon cleanup levels agreement with ADEC and EPA in 1998. TFH-diesel and TFH-gas (groundwater) and TFH-gas, TPH and "no sheen" (surface water) in the sampling program were replaced with TAH and TaqH. The revised methods and cleanup levels provide equivalent protection of human and environmental receptors and bring the cleanup levels in line with current ADEC regulations (Attachment B). Detection levels for the new methods are lower and provide data that can be compared to cleanup levels.
Groundwater sampling has shown the remedy is reducing hydrocarbon contaminants at OU5. It appears that natural attenuation for TCE is working more slowly than predicted and cleanup levels for TCE may not be met by 2026.
A wetland cell vegetation study conducted in 2001 found the wetlands to be in excellent condition. High densities of healthy plants were found, which indicates good survivability. The study also determined the optimal water level in the wetland cell that would ensure the future health of system vegetation. In addition the processes used to manage, track and enforce LUCs are working effectively to prevent potential exposure to contaminants.
There are newly promulgated state standards for five chemicals in water: 1,1-dichloroethane, 1,1,2,2-tetrachloroethane, di-n-butly phthalate, diethyl phthalate in groundwater, and naphthalene in surface water. In addition, the newly promulgated federal standard for 1,2-dichloroethane in surface water (3.8 ug/L) is stricter than the current state standard (5 ug/L), as shown in Table B-1. The new standards for 1,1-dichloroethane; di-n-butyl phthalate; diethyl phthalate; naphthalene, and 1,2-dichloroethane are greater than the maximum detected levels; therefore, the remedy is considered to remain protective for these COPCs. For 1,1,2,2-tetrachloroethane, the maximum detected level of 6.2 ug/L in 2002 exceeds the new standard of 4 ug/L. The resulting calculated risk is 2 x 10 -5 which is within EPA's risk management decision range. Protectiveness of the remedy for this compound is further assured because, 1) toxicity data and exposure assumptions have not changed for 1,1,2,2-tetrachloroethane, 2) analytical results for 1,1,2,2-tetrachloroethane are regularly received as part of the VOC analytical suite for the COCs at this site, and 3) the remedy appears to be effectively remediating similar compounds.
Additional Contaminated Seeps: Implement the plan to capture the recently discovered TCE contaminated seeps and treat them in the existing Wetland Cell. Continue to investigate the source and extent of the Kenney Ave TCE plume upgradient of the recently discovered seeps and evaluate the potential for increases in TCE concentrations. |
Jennifer Roberts |
| 7/15/2004 |
Update or Other Action |
2003 Annual Report Wetland Remediation system optimization. The following recommendations
for optimization of the WRS are based on recorded observations during the June 2003 through
August 2003 period:
• Piping between Pump Stations 1 and 2: It is recommended that the piping within Pump Station 1 and pipe runs toward Pump Station 2 are jet-flushed three to four times annually to remove iron precipitate sludge within the transport piping. This will not only ensure optimal flow rates, but should also increase the lifespan of the pumps. In addition to the above, the installation of cleanouts along the pipe run from Pump Station 1 to Pump Station 2 to further optimize system performance should also be considered.
• Flow Meters: As of mid-February, none of the flow meters in the lift stations were functioning. The iron oxide precipitate that forms naturally when the anoxic seep water adsorbs oxygen and the dissolved ferrous oxide changes to insoluble ferric oxide has a debilitating effect on the flow meters. The contractor that jetted the lines
from Lift Station 1 recommended replacing the 1½-inch lines that currently house the flow meters and replace them with 2-inch lines. This larger line size would match the minimum pipe size elsewhere in the system. A 2-inch line should be fitted with matching flow meters and installed at these locations. This should allow the iron oxide precipitate to pass through without fouling the pipes. One of the flow meters was replaced in March 2004 for evaluation.
• Beaver Impacts: Ongoing observation of the Wetland Cell should continue to minimize damage to the Wetland Cell should any more beavers take residence and block the flow of water through the V-notch weir. The Wetland Cell will be monitored as part of the weekly WRS inspection process. |
Louis Howard |
| 1/5/2005 |
Update or Other Action |
Memorandum to the Site File received. The purpose of this document (Memorandum to the Site File) is to present non-significant or minor changes to the Record of Decision (ROD)** signed for OU 5 at EAFB.
The current cleanup goals for GW, surface water & soil at OU5:
Surface water
*TAH 10 ug/L (Alaska Water Quality Standards)
*TAqH 15 ug/L (Alaska Water Quality Standards)
Hydrocarbon sheen No Sheen (Alaska Water Quality Standards)
*The ROD-specified cleanup levels for TFH-diesel & TFH-gas were conceptually modified in 1998 to include TAH & TAqH. Because there was no standard for these COCs in GW, & because the GW emerges as surface water at the seeps that eventually flow into Ship Creek (an aquaculture resource), the aquaculture water standards for TAH & TAqH are referenced. (18 AAC 70.020, based on ecological risk).
TAH – total aromatic hydrocarbon (sum of benzene, toluene, ethylbenzene, & xylenes)
TAqH – total aqueous hydrocarbon (sum of TAHs & detected polynuclear aromatic hydrocarbons [PAHs])
GW
TCE 5 ug/L (MCL)
Benzene 5 ug/L (MCL)
Soil
TFH-Diesel 1,000 mg/kg (AK Cleanup Matrix Level "C")
The minor change to the OU 5 ROD is routing of additional seeps to the constructed wetland cell for treatment. Other components to the OU 5 selected remedy will not be significantly affected by this minor change; this change is required to ensure protectiveness of remedy.
This minor revision to the ROD changes the quantity of seep water treated by the WRS by routing additional seeps to the Wetland Cell. Seeps 9, 10, & 11 were routed to the Wetland Cell in August 2004; Seeps 17 & 18 were identified flowing directly into the Wetland Cell, so no additional modification is recommended based on existing concentrations.
Seeps 9, 10, & 11 have been sampled regularly since identified in 2001. Results show that TCE continues to exceed cleanup levels (5 µg/L) at the seeps, but TCE is present at concentrations below cleanup levels immediately downgradient of the seeps, & still upgradient of Ship Creek. The potential exists for infrequent human visitors & animal contact & for exceedance of cleanup levels at the point of compliance (Ship Creek) if there were a dramatic increase in TCE from upgradient sources. The elevated TCE concentrations identified in Seeps 9, 10, & 11 are likely associated with elevated TCE concentrations found in the upgradient source area of the Kenney Avenue plume, monitored as part of the Basewide GW Monitoring program.
After seeps containing elevated TCE levels were identified in 2001 (i.e., identified Seeps 9, 10, & 11), procedures were established for adding seeps to collection areas &/or establishing other mitigation efforts to ensure protectiveness goals specified in the ROD are attained & specific remediation goals can continue to be achieved.
Seeps modification for the revised remedy: Seeps 9, 10, & 11 were routed to the Wetland Cell in August 2004. Seeps 17 & 18 were identified flowing into the Wetland Cell in 2002. Routing of flows from Seeps 9, 10, & 11 to the Wetland Cell were discussed in the August 28, 2002 meeting between the USAF, Region X of the EPA, & the ADEC. This change in the ROD does not significantly change or fundamentally affect the remedy selected in the ROD; therefore, no public comment is required.
**NOTE TO FILE: The ROD selected total fuel hydrocarbons (TFH)-diesel & TFH-gas as COCs for GW, & TFH-gas & grade 4 jet fuel as COCs in surface water. Because there was no specific cleanup standard for these compounds, the ROD set the cleanup standard at the Alaska water quality criterion for TAH. The ROD-specified cleanup levels for TFH-diesel & TFH-gas were conceptually modified in 1998 to include TAH & TAqH (USAF, 1998e). Because there was no standard for these COCs in GW, & because GW emerges at the seeps that eventually flow into Ship Creek (an aquaculture resource), the aquaculture water standards for TAH & TAqH are referenced, as documented in the 2005 OU5 memorandum to the site file.
|
Louis Howard |
| 3/21/2005 |
Update or Other Action |
Draft Final Phase I RPO Annual Report received. The notable point concerning TCE concentrations at OU5MW-02 COC trend plot of its plume is that results have historically remained quite low. Although a decreasing COC trend for this plume has not yet been identified, removal of half of the contaminant mass will likely bring TCE levels beneath the cleanup criteria of 5 µg/L.
Two wells in the vicinity of the OU5MW-02 Plume were also sampled in 2004. One of these wells, OU5MW-44, was installed in 2004 and the other, OU3MW-02, was a non-Program well already in existence. These two wells were originally associated with the Fairchild Avenue Plume and are detailed further with that plume in Section 5.7. As shown in Figure 5.4-1, these wells both exceeded the OU 5 ROD cleanup level of 5 µg/L for TCE and are located near the OU5MW-02 Plume. Therefore, it is thus recommended that wells OU3MW-02 and OU5MW-44 be associated with the OU5MW-02 Plume.
The long-term monitoring plan for the OU5MW-02 Plume should focus on monitoring TCE concentrations. Performance monitoring activities should be performed to identify a decreasing TCE trend and verify that these levels are not increasing. To optimize performance monitoring at this plume, it is recommended that the following evaluations be performed on the OU5MW-02 Plume:
COC monitoring: COC monitoring for this plume is currently performed at one well. Monitoring network optimization and sampling frequencies should continue to be determined by using the decision guides presented in Appendix H.
MNA monitoring: MNA monitoring is currently performed at each well that is sampled to ascertain COC levels. MNA samples are also collected at the same frequency at which these COC samples are collected. It is recommended that these two sampling suites be disconnected from each other and that MNA samples no longer be collected from the OU5MW-02 Plume. With the addition of well OU3MW-02 and well OU5MW-44, this plume will become a three-well plume. However, these three wells are all in-source and the closest distance between any two wells is approximately 300 feet. The distance between wells OU3MW-02 and OU5MW-02 is almost 900 feet. Because of the distance separating the wells, the potential for “interference” becomes a problem and geochemical changes observed cannot be attributed to natural attenuation with a high degree of certainty. Therefore, it is recommended that MNA sampling at the OU5MW-02 Plume be discontinued.
Cleanup date predictions: Although the OU 5 ROD allows remedial activities to proceed at this plume until 2025, it is recommended that SourceDK Tier 1 be used to predict a cleanup date for the OU5MW-02 Plume. Milestones should be manually developed when this date is known.
Contaminant mass calculations: Contaminant mass calculations cannot be determined at this plume with any high degree of accuracy because data points are insufficient to determine its mass. It is recommended that contaminant mass calculations not be performed at the OU5MW-02 Plume.
Remedy protectiveness summary: MNA is the selected remedy at the OU5MW-02 Plume. This remedy should be considered protective of human health and the environment. Although a predicted cleanup date does not exist, COC concentrations are decreasing, plume expansion is not occurring, and potential downgradient receptors are not being exposed to groundwater contaminants.
It is recommended that the COC monitoring network be reevaluated with existing decision guides and a revised cleanup date for this plume be developed during summer 2005. These exercises should be performed and the findings should be submitted as a stand-alone report before the 2005 Annual Report is prepared. The results of the reevaluation would not be generated in time to guide field activities during 2005, but would be available to influence recommendations in the 2005 Annual Report.
|
Louis Howard |
| 3/22/2005 |
Update or Other Action |
2004 Phase I RPO Annual Report (Draft Final) Groundwater Performance Optimization Monitoring Program received. To optimize performance monitoring at the Slammer Avenue Plume, it is recommended that the following tasks be performed at this plume in 2005:
Contaminant of Concern (COC) monitoring: The COC monitoring and contaminant mass calculations at the Slammer Avenue Plume should be performed by using MAROS. This plume contains the requisite input data requirements for MAROS, which offers improved performance of optimization efforts in comparison to the use of existing decision guides.
Contaminant mass calculations: MAROS will be used for monitoring network optimization at this plume. It is recommended that MAROS also be used to perform contaminant mass calculations.
MNA monitoring: MNA monitoring should be reduced to a 5-year frequency. An evaluation of MNA results in 2004 strongly indicates that natural attenuation is not active at the Slammer Avenue Plume. This finding is supported by historical analytical results.
Cleanup date predictions: It is recommended that a revised cleanup date be calculated and compared with the OU 5 ROD prediction of 2025. A new cleanup date should be developed for the Slammer Avenue Plume by using SourceDK Tier 2. However, it must be noted that the absence of a decreasing trend and the poor performance of natural attenuation may limit the ability of Tier 2 to calculate a cleanup date. If the calculation proves problematic, additional data collection or investigation activities may be required to develop a revised cleanup date. Milestones should be developed manually when this cleanup date is known.
Remedy protectiveness summary: MNA is the selected remedy at the Slammer Avenue Plume. It is uncertain whether this remedy should be considered protective of human health and the environment. It is likely that groundwater with low TCE concentrations (less than 5 ug/L) is bypassing the Beaver Pond; however, it is not known whether this COC is entering Ship Creek.
It is unlikely TCE in excess of 5 ug/L is reaching Ship Creek from the Slammer Avenue Plume because dispersion and dilution act to decrease the TCE concentrations.
It is recommended that the COC monitoring network optimization efforts, contaminant mass calculations, and cleanup date development for the Slammer Avenue Plume be performed during the summer of 2005. These exercises should be performed and the findings should be submitted as a stand-alone report before the 2005 Annual Report is prepared. The results of the reevaluation would not be generated in time to guide field activities during 2005, but would be available to influence recommendations in the 2005 Annual Report. |
Louis Howard |
| 4/1/2005 |
Document, Report, or Work plan Review - other |
The Alaska Department of Environmental Conservation (ADEC) received the 2004 RPO Report on March 21, 2005. Below are ADEC’s comments on the document.
General Comments
Typically, delineating a plume of contaminated groundwater takes more than one well in the source area. ADEC requests the Air Force redraw boundaries for “plumes” in the following figures where one well is defining a “plume” of contaminated groundwater with a bold line and replace it with a dashed line to show it as being “inferred” or “interpreted” rather than a distinct boundary.
Zone 1
Figures 3.2-1 and 3.3-1 for wells: OU6MW-46 and OU6MW-63
Figure 3.3-3 for well OU6MW-46
Figures 3.5-1 and 3.6-1 for well ST41-10R
Figure 3.9-1 for wells: OU6MW-46 and OU6MW-63
Figure 3.10-1 for well OU6MW-46
Zone 2
Figure 4.1-1 for well 59WL-31
Figure 4.3-1 for well SP7/10-04
Figures 4.3-1 and 4.5-1 for well OU4MW-04
Figure 4.6-1 for well OU4MW-08R
Figure 4.7-1 for IS6-01
Figures 4.9-1 and 4.10-1 for wells: SP7/10-04 and W-4
Zone 3
Figure 5.3-1 for well OU3MW-25
Figure 5.5-1 for wells: 60WL-04 and 64WL-01
Figure 5.6-1 for wells: 64WL-01 and 62WL-05
Figure 5.10-11 for well LF59MW-03
3.2.4 Phase I RPO Conclusions and Recommendations
Verifying that plume expansion is occurring with one monitoring well is nearly impossible to do without additional monitoring wells. The text states that the OU6 ROD mandated 5-year reviews be performed to evaluate the performance of the selected remedy (MNA). However, the recommendation in this section for MNA monitoring states MNA assessments cannot be accurately performed at one-well plumes. Also the text states plume expansion is not occurring and potential downgradient receptors are not being exposed to groundwater contaminants. ADEC requests clarification on how it can be demonstrated with one monitoring well that downgradient receptors are not being exposed to groundwater contaminants and whether or not it can be shown a plume is expanding or shrinking when sampling data is limited to one well.
The comments above apply to: PL81 South Plume (Section 3.3.5), ST41 North Plume (Section 3.5.4), 59WL-31 (Section 4.1.5), Hangar 10 Plume (Section 4.5.4), Hangar 11 Plume (Section 4.6.4), OU4 East Plume (Section 4.7.5), SS43 Plum (Section 4.9.4), W4 Plume (Section 4.10.4), OU3MW-25 Plume (Section 5.3.4), and SP01-2 Plume (Section 5.8.4).
7.0 Phase I RPO Recommendations Summary Page 7-1
ADEC concurs with updating the conceptual site models for inclusion in the 2005 Program Baseline Calculations Report.
7.1 Plume-Specific Recommendations
ADEC concurs with the plume-specific recommendations listed in this section which are not provided in Table 7.1-1. |
Louis Howard |
| 2/14/2006 |
Document, Report, or Work plan Review - other |
Staff commented on the Draft Treatability Study Work Plan Enhanced Bioremediation at the Slammer Avenue Plume, Operable Unit 5, Elmendorf AFB dated January 2006.
The text states baseline sampling will be conducted at nine new groundwater monitoring wells, one existing well, and two existing surface water monitoring points. Absent from Table 4.4 is analyzing for TAH - total aromatic hydrocarbons (10 µg/l) and TAqH -total aqueous hydrocarbons (15 µg/l) in surface water (see 18 AAC 70.020(b)). Elmendorf has been analyzing for TAH and TAqH as contaminants of concern in the 2005 Annual Activities Addendum Groundwater Monitoring Program (Table 3-3 Zone 3 OU5 page 3-7 for the Bluff Pipeline and Kenney Avenue and page 3-8 for SP1-02). ADEC requests including TAH and TAqH analyses for surface water sampling proposed for the Slammer Avenue work plan.
NOTE to file: The 1995 Record of Decision for OU 5 states “Treated water discharged from wetlands into Alaska surface waters will be controlled to ensure that the quality of the receiving waters meets the organic standards for fresh water set forth under 18 AAC 70.020.(Section 5.1.2 Page 5-6).”
Current 18 AAC 70.020 reg states: Samples to determine concentrations of total aromatic hydrocarbons (TAH) and total aqueous hydrocarbons (TAqH) must be collected in marine and fresh waters below the surface and away from any observable sheen; concentrations of TAqH must be determined and summed using a combination of: (A) EPA Method 602 (plus xylenes) or EPA Method 624 to quantify monoaromatic hydrocarbons and to measure TAH; and (B) EPA Method 610 or EPA Method 625 to quantify polynuclear aromatic hydrocarbons listed in EPA Method 610; use of an alternative method requires department approval; the EPA methods referred to in this note may be found in 40 C.F.R. 136, Appendix A, as revised as of October 23, 2003 and adopted by reference.
Register 24 January 1993 in effect when 1995 ROD was signed states: Total hydrocarbons in the water column shall not exceed 15 ug/l, or 0.01 of the lowest measured continuous flow 96 hour LC50 for life stages of species identified by the department as the most sensitive biologically important species in a particular location, whichever concentration is less. Total aromatic hydrocarbons in the water column shall not exceed 10 ug/l, or 0.01 of the lowest measured continuous flow 96 hour LC50 for life stages of species identified by the department as the most sensitive biologically important species in a particular location, whichever concentration is less. Concentrations of hydrocarbons, animal fats, or vegetable oils in the sediment shall not cause deleterious effects to aquatic life. Shall not cause a film, sheen or discoloration on the surface or floor of the water body or adjoining shorelines. Surface waters shall be virtually free from floating oils. |
Louis Howard |
| 5/29/2006 |
Update or Other Action |
2005 Annual Phase I RPO Report received. ST37 is comprised of 6 plumes, which contain a total of 26 monitoring wells, 9 seeps, & 4 surface water locations; the Early Warning Line, which contains 5 monitoring wells; & the Sentry Well network, which contains 11 monitoring wells.
The selected remedy for the 6 plumes within ST37 is MNA with LTM/LUCs. Monitoring of each of the plumes is on-going per the OU 5 ROD. In-place LUCs strictly prohibit use of the shallow aquifer for any reason. These LUCs will be continued until all COCs are below OU 5 ROD-specified cleanup levels. Based on this land use scenario, no human or environmental exposure to the contaminated GW is expected. Remediation workers are adequately protected & follow established health and safety procedures.
The 2002 5 Year Review found the remedy is functioning as intended in the OU 5 ROD, and exposure assumptions, toxicity data, cleanup levels, & RAOs used at the time of the remedy selection were still valid. The review indicated additional seeps containing TCE in excess of cleanup levels had been discovered. These seeps have since been diverted to the OU 5 Wetlands Remediation System.
The effectiveness of monitoring well networks at each of the plumes to adequately track potential migration toward potential human or ecological receptors varies. Both the Fairchild Avenue Plume and Kenney Avenue Plume have adequate monitoring well networks with downgradient wells. The OU5MW-02 Plume, Slammer Avenue Plume, & SP1-02 Plume each have only in-source wells (no downgradient wells); however each of these plumes is monitored by downgradient seeps.
The OU3MW-25 Plume is monitored by only 1 well, which is in-source. Both the SP1-02 and OU3MW-25 plumes are stable plumes. Since these plumes have modeled decreasing trends in contaminant levels, natural attenuation processes are acting to remediate the plume margins. Therefore, tracking potential migration toward receptors is adequate.
The current monitoring well network appears to be INADEQUATE to track potential migration of the OU5MW-02 and Slammer Avenue plumes due to a lack of close proximity downgradient wells. In general, results from over 10 years of modeling & monitoring similar contaminants from other plumes on Base with extensive monitoring well networks indicate plumes such as this do not migrate far from their source areas.
However, the OU5MW-02 and Slammer Avenue plumes are considered to be unstable plumes without modeled decreasing trends in contaminant levels. Though natural attenuation processes are acting to remediate the plume margins, the LACK of a decreasing trend suggests that additional plume migration is possible. Based on these findings, additional downgradient monitoring of these plumes may be necessary.
The most recent 5 Year review suggests the natural attenuation remedy for these plumes should be considered protective of human health and the environment, a review of the network in place to assess the effectiveness of the remedy is required. A recommendation will be made to re-assess the GW monitoring network for these plumes as part of a review of the CSM. The CSM reviews will be conducted in 2006. Recommendations for changes to the monitoring network to ensure its protectiveness will be made as part of the CSM evaluation.
The EAFB GW monitoring network includes a line of sentry wells as well as an “early warning line” to identify any contamination which threatens to migrate off-site. As such, the plumes with a NON-decreasing trend do not pose an immediate threat to human health or the environment, however, a review of the well network, as noted above, is still warranted.
Monitoring data from 24 of the 26 GW wells, 9 seeps & 4 surface water locations were collected from 5 of the 6 plumes at ST37 in 2004. Monitoring data shows TCE remains above the OU 5 ROD cleanup level in all 5 plumes sampled in 2004. Plume OU3MW-25 was last sampled in 2002 &monitoring data from that event shows TCE slightly exceeded the OU 5 ROD cleanup level. Monitoring of the Zone 3 Early Warning Line & Sentry Well networks indicates that contaminated GW is being captured & treated upgradient of Ship Creek. GW monitoring at ST37 is on-going per requirements of the OU 5 ROD.
LUCs at ST37 are in-place & are preventing exposure pathways that could result in an unacceptable risk. 5 Year reviews are being conducted per the OU 5 ROD to monitor the effectiveness of the LUCs in place.
Note that a system performance evaluation was not conducted for the Sentry & Early Warning Line locations. A model-predicted cleanup date could not be generated for 3 plumes within ST37 because a decreasing data trend is NOT evident. A detailed assessment of remedy effectiveness, including a review of MNA parameters, will be performed in 2006 as part of the 2006 RPO Evaluation. |
Louis Howard |
| 8/16/2006 |
Offsite Soil or Groundwater Disposal Approved |
Staff reviewed and approved a request for transport and treatment of 4 drums of drill cuttings from well installation in Slammer Plume fuels and chlorinated solvent plume. |
Louis Howard |
| 2/26/2007 |
Exposure Tracking Model Ranking |
|
Louis Howard |
| 10/15/2008 |
CERCLA ROD Periodic Review |
5 YR Review
Site Inspection
The WRS system was inspected & found to be operational. Mr. Marty Hannah, the system operator, reported O&M problems with maintaining pumps & corrupted program control logic (resulting in false alarms). The pump stations & overland flow cell are individually fenced & locked. The WRS & pump stations are located on the property easement purchased from the ARRC. Seep 7 is not incorporated into the WRS; it flows into a ditch & mixes with effluent from the WRS just below the discharge point.
All active monitoring wells, including early warning & sentry wells, were located. One had a broken cover (probably due to frost heaving), one had a cracked concrete pad, & two showed minor frost heaving. There was no evidence of unauthorized wells or any other site disturbance.
Issues
Fairchild Avenue Plume Downgradient Boundary: The downgradient extent of the Fairchild Avenue plume is delineated at the water table but not in wells screened deeper in the shallow aquifer. TCE has not been detected in downgradient seeps, downgradient early warning/sentry wells, or in Ship Creek, but was detected in a downgradient ARRC well in 2002.
Contaminated Seep: In 2005 & 2006, the TCE concentration in Seep 7 increased to just above the cleanup level. The decision guide for restarting an existing seep collection area or adding a new seep collection area for treatment (Attachment F, Figure F-4) indicates that the response for this seep should be quarterly monitoring.
Cleanup Schedules: Monitoring shows that the natural attenuation remedies are generally decreasing COC concentrations. At several sites, the process is slower than anticipated in the ROD. For most of the affected sites, the slower attenuation rates are limited to a few individual wells or just a few additional years until cleanup goals are met. The slower rates of natural attenuation have the largest impact at OU5, where natural attenuation may take several additional decades to reach cleanup levels. OU5 has a large monitoring program & a relatively expensive treatment system for contaminants discharging at seeps, so the impact on cleanup costs could be significant. In the interim, LUCs are in place to ensure protectiveness.
Recommendations/Follow-up Actions
Fairchild Avenue Plume Downgradient Boundary: Define the downgradient limit of the Fairchild
Avenue plume in the deeper portions of the shallow aquifer.
Contaminated Seep: Increase the monitoring frequency for Seep 7 to quarterly in accordance with the decision guide in the 2005 OU5 memorandum to the site file.
Cleanup Schedules: Continue monitoring until cleanup levels are met. Continue to use trend
analysis to evaluate the natural attenuation remedies. Adjust estimated dates for achieving GW cleanup in accordance with trend projections. For OU5, attempt to identify sources of TCE contamination for Fairchild Avenue, OU5MW-02, SP1-02 Kenney Avenue, & Slammer Avenue plumes. If sources can be identified, evaluate alternative remedial strategies to accelerate attainment of the TCE cleanup level in OU5 GW. LUCs shall remain in place to ensure protectiveness until cleanup goals are met.
Resample well OU3MW-25 (OU3MW-25 plume) to confirm that TCE concentration remains below the cleanup level. If confirmed, prepare memorandum to site file to document that sampling for this plume should be discontinued.
Optimize early warning & sentry monitoring well networks to eliminate wells that are not
downgradient of plumes & consider additional wells where there is a greater probability of
contaminant migration.
High O&M costs for the WRS are attributed primarily to the moving parts (pumping systems).
Evaluate the feasibility of shutting down pump stations. Pump station 2 can be mothballed in
accordance with the decision guide for shutting down pumping stations because Seep 3 has met
cleanup levels for the past five years. Seep 1 may be diverted from Pump Station 1 since it has
also met cleanup levels for the past five years. This would leave only Seep 2 discharging to Pump Station 1, which would then only have to operate at a fraction of its current flow rate.
See site file for additional information. |
Louis Howard |
| 2/23/2009 |
Document, Report, or Work plan Review - other |
Draft Zone 3 Mgt. Area Annual Report January 2009 review letter sent to Air Force (M. Markell). ADEC requests the Air Force submit completed ADEC Laboratory Data Review checklist(s) (currently version 2.5) with this report for review as required by ADEC Technical Memorandum 06-002 (October, 9, 2006). ADEC has determined that the quality assurance submittals described in the memorandum are necessary to meet requirements of 18 AAC 75.335 (b) (2) (B) & (G), 75.335 (c) (3) & (4), 75.355 (a), 75.360 (2) and 18 AAC 78.007. However, if an independent third party conducted the data quality assessment for data validation (other than OASIS or PARSONS) which meets the requirements of the checklist, then the review presented in the document would be sufficient. Please provide the name of the company/agency that conducted the review. Otherwise, please complete the checklist(s). This matter was raised in a previous letter to the Air Force (April 2007 ADEC letter on Draft Annual Monitoring Field Report Zone 3).
2.4.2 Groundwater Analytical Results Page 2-2: The text states groundwater samples were collected from wells LF59MW-03 and LF59MW-06R and from the two up gradient compliance monitoring wells, OU1LF-19 and LF05GW-2B. The trichloroethene (TCE) concentrations in the two compliance wells exceeded cleanup criteria (5 µg/L) in 11 of the 19 discrete groundwater samples collected during the compliance program investigations. This fact combined with the results from the Compliance Program “Operable Unit 1 Landfill Corrective Measures Study Report December 2008 draft” calls attention to additional plumes downgradient from landfill cells LF07, LF07A (Southern Plume and LF13 (Northern Plume).
It appears the assumptions in the Final CERCLA Site Closure Report for Sites (source areas) LF05, LF07, LF13, and OT56 (2004) which was signed by the Air Force, EPA and ADEC are no longer valid. The closure document documented (at that time) all remedial actions and objectives specified in the Record of Decision (ROD) have been met in accordance with CERCLA and thus were eligible for closure.
Source areas LF07 (includes LF07A cell) and LF13 are above their respective ROD cleanup goals for TCE. LF05GW-2B, OU1LF-19, SP-14, and SP-15 may be more properly associated with groundwater contamination from LF07 and LF07A. Grab samples taken by the Compliance Program downgradient from LF13 were found to be above ROD established cleanup level of 5 ug/L for TCE (SP:26: 9 ug/L, SP-10 9.6 ug/L, SP-09 14 ug/L, and SP-07: 11 ug/L). Additionally, LF59 has had groundwater detections of 1,1,2,2-Tetrachloroethane (PCA) during previous investigations and in September 2008 (at a concentration of 8.6 ug/L) which may be attributed to another VOC source in the western portion of LF59 (Page 5-8 of the 2008 OU1 Corrective Measures Study Report).
3.3.3.1 Groundwater Elevation Measurements Page 3-4: The text states that the water elevations in Fairchild Avenue plume wells were not used to develop the zone-wide groundwater contours because water levels were above the top of the screen at all locations. ADEC requests clarification on whether or not the Air Force will address this issue by installing additional wells so that zone-wide groundwater contours on Figure 1.2 can be developed. If not, then ADEC requests the Air Force to explain why the information is not needed as part of the groundwater monitoring in Zone 3.
3.3.3.2 Groundwater Analytical Results Page 3-5: The text states no other compounds besides TCE were detected above the cleanup levels. The sentence should state: “No other compounds were detected above the cleanup levels identified in the 1995 OU5 Record of Decision.” Well OU3MW-11 June 16, 2008 sample results showed tetrachloroethylene (PCE) at 6.1 ug/L which is above cleanup levels established by 18 AAC 75.345 Table C for PCE. TCE may be a daughter product of reductive dechlorination of PCE which is a process of natural attenuation that the Air Force is relying on to achieve cleanup in groundwater at OU5.
3.4.2.1 Groundwater Elevation Measurement Page 3-7: ADEC requests clarification from the Air Force on the significance of having the two wells used for monitoring TCE being screened at shallow intervals across or near the water table. Generally, deeper wells may be necessary to determine the vertical extent of contamination if a significant dissolved portion is present. DNAPLs may exhibit overall vertical migration even if horizontal ground water flow predominates; therefore, at a minimum, screens need to be placed at or near the bottom of a saturated zone or just above a confining layer instead of at or near the water table. Multiple wells completed at different depths may be required if both LNAPLs and DNAPLs are present.
|
Louis Howard |
| 3/17/2009 |
CERCLA ROD Periodic Review |
Cover letter to the EPA's Five-Year Review signature sheet sent to Richard J. Walberg, Colonel, US Air Force Vice-Commander from EPA Region 10 Office of Environmental Cleanup Daniel D. Opalski, Director. The Environmental Protection Agency (EPA) has completed their review of the third Five-Year Review report for the United States Air Force (USAF) Elmendorf Superfund site, in Anchorage Alaska.
EPA reviewed this report for technical adequacy, accuracy, and consistency with EPA guidance. In general, EPA agrees with the protectiveness determinations in this report. However, I understand that all parties to the Comprehensive Environmental Response, Compensation, and Liability Act (CERCLA) Section 120 Federal Facility Agreement (FFA) are aware of a potential new source that has not been fully characterized, namely SS-022. It is also my understanding that while the Five-Year Review identifies this potential new source, the USAF has not adequately discussed the interim measures it has already taken to ensure protectiveness as site characterization proceeds, such as Institutional Controls (ICs) at SS-022 and the ongoing Remedial Investigation.
Therefore, we recommend that within ninety (90) days (by June 15, 2009), USAF supplement the Site File and Administrative Record with a Memorandum to document the ICs (e.g., installation of a fence, signage, and notation on the Environmental Restoration Program Atlas) that have been implemented for the protection of human health and the environment at SS-022. The Memorandum should also mention the Installation-wide ICs (including restriction of ground water use) already in place.
In addition, EPA agrees with USAF's recommendation for further action at the OU-l landfill area for the trichloroethylene (TCE) groundwater contamination, and requests that the Program Managers meet to discuss the timeline for completion of the groundwater contamination characterization and establish deadlines and, as appropriate, target dates for subtasks, as required under the FFA.
|
Louis Howard |
| 3/31/2009 |
Update or Other Action |
Final work plan received. The work plan describes tasks that will be performed in 2009 within the Zone 2 and Zone 3 Management Areas at Elmendorf Air Force Base (AFB), Alaska. This work plan outlines the 2009 scope of work for four sites in the Zone 3 Management Area: ST37, ST48, ST68, and LF59. Site ST37 includes several discrete plumes including the Fairchild Avenue Plume, Kenney Avenue Plume, Slammer Avenue Plumes, OU3MW-25 Plume, OU5MW-02 Plume, and SP1-02 Plume. In addition to these plumes, Site ST37 includes groundwater seeps and surface water locations near the southern boundary of the base, the Beaver Pond, the Operable Unit (OU) 5 engineered wetland remediation system (WRS), and the early warning and sentry well networks.
Zone 3 also includes operation, maintenance, and monitoring (OM&M) of the Restoration Staging Facility, which is also commonly referred to as the “Contractor’s Yard”.
ST37 (OU5) contains various plumes and the Early Warning Wells (6) and Sentry Wells (11) for the Base which are sampled seminannually (April and August). These wells will sample COCs semiannually (summer/winter) with passive diffusion bags.
Six early warning and eleven sentry wells will be sampled semiannually in 2009 using passive diffusion bag samplers (PDBS). These wells are located in the southern portion of ST37. The Sentry Wells are located downgradient of the early warning line and OU 5 plumes. Early Warning Wells provide early detection of TCE from upgradient plumes before the contamination impacts Ship Creek or other downgradient environmental receptors. The PDBS will be placed in the monitoring well for at least two (2) weeks prior to retrieval. The procedure for collecting samples with PDBS is described in SOP No. 13. Field water quality parameters, such as temperature, conductivity, pH, DO, ORP, and turbidity will not be monitored. Groundwater samples will be transferred from the PDBS to appropriate sample containers. Sample containers and preservation methods are addressed in SOP No. 15 of the FSP. Samples from early warning and sentry wells will be analyzed for VOCs.
SOP #13: The typical passive diffusion bag (PDB) consists of a low-density polyethylene layflat
tube closed at both ends and is filled with analyte-free deionized water. The PBD membrane acts as a semi-permeable membrane to certain contaminants, specifically chlorinated VOCs. VOCs in the groundwater diffuse across the membrane into the deionized water in the bag until equilibrium is established between the diffusible VOC in the groundwater and in the deionized water. The PDBs will be filled with water by the supplier and set with dedicated hardware.
The PDBs will be placed in the monitoring wells approximately 1 foot from the bottom of the well and will be attached with a nylon string to the top of the well casings. The PDBs will be left in the wells for approximately two weeks and at that time will be removed and used to fill three VOA vials for each monitoring well sampled. The samples will be handled as previously described for groundwater samples. Field parameters will not be taken as part of the analysis for PDB samples; however, the depth to groundwater and bottom of the well will be recorded on a
passive diffusion sampler data sheet included in an attachment to the FSP. The condition
of the wells will be recorded on the sampling form.
Winter conditions may affect installation of PDBs. In some cases during extremely cold temperatures, ice may form inside the casing and require removal prior to inserting the PDB. Groundwater inside the well may also partially solidify and become slushy. Under this circumstance, the PDB cannot be lowered to the appropriate depth within the well. A stainless steel bailer or purge block will be lowered into the well and used to mix the well water column and effectively reduce sludge so the PDB can be lowered to the appropriate depth. PDBs will remain in the well for at least two (2) weeks before samples are collected. |
Louis Howard |
| 4/13/2009 |
Update or Other Action |
Staff received for review: 2009 Zone 2 and Zone 3 Management Areas Work Plan. This work plan outlines the 2009 scope of work for four sites in the Zone 3 Management Area: ST37, ST48, ST68, and LF59. Site ST37 includes several discrete plumes including the Fairchild Avenue Plume, Kenney Avenue Plume, Slammer Avenue Plumes, OU3MW-25 Plume, OU5MW-02 Plume, and SP1-02 Plume. In addition to these plumes, Site ST37 includes groundwater seeps and surface water locations near the southern boundary of the base, the Beaver Pond, the Operable Unit (OU) 5 engineered
wetland remediation system (WRS), and the early warning and sentry well networks.
Zone 3 also includes operation, maintenance, and monitoring (OM&M) of the Restoration Staging Facility, which is also commonly referred to as the “Contractor’s Yard”.
The 1995 ROD for OU 5 specifies the selected remedy for Site ST37, which includes monitored natural attenuation (MNA) and treatment of contaminated groundwater seeps by the WRS.
The COCs originally specified for Site ST37 include benzene, TCE, total fuel hydrocarbons-gasoline range (TFH-gas), and TFH-diesel range. The USAF and the regulating agencies have agreed to utilize Alaska Department of Environmental Conservation (ADEC)-method defined hydrocarbon ranges for GRO and DRO as replacement COCs/analytical methods for TFH-gas and TFH-diesel in groundwater, respectively. The ROD-specified COCs for surface water and
seeps originally included TFH-gas and grade 4 jet propulsion fuel (JP-4). These were
replaced in 1998 with total aromatic hydrocarbons (TAH) and total aqueous hydrocarbons (TAqH) as defined in Alaska’s Water Quality Standards (Title 18 Alaska Administrative Code Chapter 70 [18 AAC 70]. This modification was officially acknowledged in a 2005 memorandum to the site file. Based on recent monitoring data, the only COC concentrations that remain above cleanup levels in Site ST37 seeps, surface water, and groundwater are TCE, benzene, TAH, and TAqH.
ST37 consists of the following plumes: Fairchild Avenue Plume (8 wells), Kenney Avenue Plume (2 wells), Slammer Avenue Plume (4 wells), OU3MW-25 Plume (1 well), OU5MW-02 Plume (2 wells), SP1-02 Plume (2 wells), Seeps and Surface water (10 seeps, 10 sampling points), and the Early Warning (6 wells) and Sentry Well Network (11 wells). |
Louis Howard |
| 4/30/2009 |
Document, Report, or Work plan Review - other |
Staff provided comments on the Draft 2008 Zones 2 and 3 Management Areas Work Plan, March 2009
for Elmendorf Air Force Base, Alaska.
2.4.5 Seep and Surface Water
The text states PAH and VOC concentration data will be used to calculate total aromatic hydrocarbons (TAH) and total aqueous hydrocarbons (TAqH) concentrations to evaluate results against Alaska’s water quality standards presented in 18 AAC 70. ADEC concurs. Typically at other contaminated sites where TAH and TAqH concentrations are calculated, ADEC requests the responsible party to use one-half (1/2) of the practical quantitation limit (PQL) and not the method detection limit (MDL) for non-detects (NDs) in the calculation of TAH and TAqH.
2.9.3.2.2 Pump Station #1
Background Data Supporting Proposed Optimizations Page 2-39
The text states results for target analytes that were detected above the reporting limit were used to calculate the maximum TAH concentration. Typically at other contaminated sites where TAH and TAqH concentrations are calculated, ADEC requests the responsible party to use one-half (1/2) of the practical quantitation limit (PQL) and not the method detection limit (MDL) for non-detects (NDs) in the calculation of TAH and TAqH.
Proposed PS #1 Optimization Study Activities for 2009 Page 2-41
The text states if the cleanup standards for benzene, TAH, or TAqH are exceeded in any effluent samples from the PS #1 SCA, PS #1 will be restarted and this portion of the optimization test will be terminated. Typically at other contaminated sites where TAH and TAqH concentrations are calculated, ADEC requests the responsible party to use one-half (1/2) of the practical quantitation limit (PQL) and not the method detection limit (MDL) for non-detects (NDs) in the calculation of TAH and TAqH.
Pumphouse PS #2 Optimization Study Activities for 2009
Contingencies Page 2-44
The text states that one of the conditions that would lead to a re-start of the pumping include COC concentrations in annual samples collected from OU4SP-03 that exceed applicable cleanup standards. Typically at other contaminated sites where TAH and TAqH concentrations are calculated, ADEC requests the responsible party to use one-half (1/2) of the practical quantitation limit (PQL) and not the method detection limit (MDL) for non-detects (NDs) in the calculation of TAH and TAqH.
Proposed WTC Optimization Study Activities Page 2-45
The text states if concentrations of TCE and all other COCs in the WTC effluent remain below applicable standards... the USAF may seek concurrence from USEPA and ADEC to continue bypassing the OFC indefinitely. Typically at other contaminated sites where TAH and TAqH concentrations are calculated, ADEC requests the responsible party to use one-half (1/2) of the practical quantitation limit (PQL) and not the method detection limit (MDL) for non-detects (NDs) in the calculation of TAH and TAqH.
SOP #13 Groundwater Sampling
Passive Diffusion Bag Sampling Attachment 1-31
ADEC concurs with the tasks and approach outlined in this section. There are some limitations regarding passive diffusion bag (PDB) sampling. Passive samplers do not provide direct or real-time data. PDB samplers cannot be used for all contaminants; metals and other inorganic compounds will not diffuse through the membrane. The general target is non-polar VOCs with a molecule size of less than 10 angstroms. Biofouling can make PDBs less effective. PDB sampling in monitoring wells relies on the presence of an uninhibited horizontal water flow.
Other factors, such as vertical flow, biofilms, or iron fouling may negatively affect the quality of PDB sampling data. Well stratification can be an issue even in wells with small screened intervals. If PDB samplers are used to identify the highest potential concentration in a well, numerous linked samplers may be needed to decide on the optimal placement of the final sampler.
SOP # 14 Subsurface Soil Sampling Attachment 1-34
ADEC requests the Air Force clarify text in the second paragraph regarding VOC/GRO samples collected concurrently will not be emptied into a stainless steel bowl for homogenization prior to filling the sample jars. |
Louis Howard |
| 11/11/2009 |
Update or Other Action |
Draft MEMORANDUM TO THE SITE FILE Elmendorf Air Force Base Operable Units (OUs) 1,2,4, and 5 received. The minor revisions to the OU 1,2,4 and 5 RODs clarify how LUCs will be implemented and managed for activities within these operable units. In addition, this minor revision will correct inconsistencies to chemical specific ARAR in the Operable Unit 4 ROD. In 2003, the USAF published guidance for active installations entitled Air Force Policy on Performance-Based Records of Decision (RODs) for Land Use Control (LUC) Implementation (SAF/IE Memo, 7 Oct 03) requiring documentation of LUCs in administrative documents such as the ROD. LUCs are part ofthe selected remedies in the RODs for OUs 1,2,4, 5, and 6 and Site DP98. This Memorandum to the Site File uses the 2003 guidance to clarify how the USAF intends to implement the LUCs at OUs 1,2,4 and 5. The ROD for Site DP98 is compliant with USAF Policy. The ROD for OU 6 was updated to be compliant with the policy in an Explanation of Significant Difference dated 15 June 2007. The cleanup for OU3 is complete and no LUCs are in place as part of the remedy.
Land Use Control Performance Objective: Restrict access to the contaminated groundwater throughout OU5 until cleanup levels have been achieved.
Proposed minor change-Groundwater: Institutional controls (also called LUCs) that prohibit use of the upper aquifer will ensure that people will not be exposed to contaminated groundwater until cleanup goals are achieved. Land Use Controls will be managed and implemented in accordance with section 4.1 of this memorandum to site file. The Land Use Control boundaries are depicted in Figures 4.3 and 4.4 of this memorandum to site file. |
Louis Howard |
| 12/1/2009 |
Update or Other Action |
Semi-annual progress report received. SUMMARY OF WORK PERFORMED DURING LAST SIX MONTHS-Conducted optimization study of wetland remediation system, including increased sampling frequencies and improvements to drainage near seep areas (Apr 09 – Oct 09), Performed quarterly, semi-annual, and annual groundwater and surface water sampling (ongoing) and Distributed Final 2008 Zone 3 Management Area Annual Report (Aug 09).
PLANNED ACTIVITIES FOR NEXT SIX MONTHS-Continue limited operation of the wetland remediation system in conjunction with the extended Wetland Optimization Study (Oct 09 – Apr 10), Finalize minor site letter for clarification of land use controls (LUCs) at OUs 1, 2, 4, and 5 (Jan 10),
Submit Draft 2009 Annual Monitoring Report to agencies (Feb 10) and Perform quarterly, semi-annual, and annual groundwater and surface water sampling (annual event in Jun 10). |
Louis Howard |
| 2/3/2010 |
Document, Report, or Work plan Review - other |
Staff reviewed and commented on the Draft Zone 3 Management Area Wetland Remediation System Optimization Study, December 2009 Elmendorf Air Force Base, Alaska. The text in the document on pages 1 and 5 refer to the Record of Decision (ROD) (United States Environmental Protection Agency [USEPA] for Operable Unit 5. The reference should be for the United States Air Force (USAF) and not the U.S. EPA since it is the Air Force's Operable Unit 5 on Elmendorf Air Force Base which the referenced Record of Decision was developed and finalized.
1. Introduction Paragraph 2 Page 1-The text states: "As presented in the Record of Decision (ROD) (United States Enviromnental Protection Agency [USEPA], 1995) for Operable Unit 5 (OU 5), the remedy for this area includes operation and monitoring of an engineered Wetland Remediation System to collect and remediate petroleum, oil and lubricants (POL)-contaminated seep water associated with the south bluff of Elmendorf AFB." ADEC requests the Air Force add text from the OU 5 ROD in this section which describes the specific components of the selected remedy applicable to this study.
OU 5 Specific Components of the Selected Remedy-
• Groundwater will be monitored to estimate the rate of natural attenuation, to provide an
early warning of potential off-site contaminant migration, and to ensure protection of human health and the environment.
• Water will be monitored near the exit of the constructed wetland to ensure that the wetland is reducing concentrations to below the Alaska water quality standards.
• Water from the seeps and beaver pond wetland areas will be monitored to estimate the
rate of natural attenuation and make sure that contamination does not reach Ship Creek.
2. Purpose and Objectives Paragraph 1 Page 5-The text states: "The purpose of the Optimization Study was to allow testing of various Wetland Remediation System operational configurations while also ensuring that the system continues to meet treatment objectives established by the ROD and requirements of state regulations (USEP A, 1995)."
ADEC requests the Air Force list the remedial action objectives from the OU 5 ROD in this
section.
OU 5 Remedial Action Objectives
• Protect human health and the environment by preventing ingestion and contact with contaminated groundwater by people and preventing animal contact with contaminated seep water;
• Vse treatment techniques whenever practicable;
• Implement a solution that is capable of managing impacts from up gradient sources as the contaminants reach OU 5; and
• Implement a cost effective solution that can achieve the cleanup levels for the final COCs.
4. Conclusions and Recommendations Page 23-ADEC requests the Air Force document the Phase III results when they verify the conclusions of Phases I and II as a Memo to the Site File documenting the operational changes, if the EPA remedial project manager concurs it qualifies as a non-significant (or Minor) Post-ROD change or if it is a significant/fundamental change to the remedy.
5 References Page 27-ADEC requests the reference to United States Environmental Protection Agency be changed to the United States Air Force in the reference and include Operable Unit 5 as there are multiple RODs for Elmendorf Air Force Base. |
Louis Howard |
| 2/16/2010 |
Update or Other Action |
Staff received the draft 2009 Zone 3 Management Area Annual Report Environmental Restoration Program. The plumes associated with Site ST37 include the Fairchild Avenue Plume, Kenney Avenue Plume, Slammer Avenue Plumes, OU3MW-25 Plume, OU5MW-02 Plume, & SP1-02 Plume. In addition to these plumes, Site ST37 includes seeps & surface water locations near the southern boundary of the base & the Early Warning & Sentry Well Networks.
Fairchild Avenue plume: The 2007 RPO evaluation identified the Fairchild Avenue Plume as a Red priority site because TCE levels in deeper, downgradient wells OU5MW-34 & OU5MW-38 were not decreasing, & therefore a cleanup date could not be predicted. TCE levels at these two wells & at OU3MW-11 which is closer to the source area, in 2009 were similar to 2008 levels. Because a decreasing trend is still not evident for OU5MW-38, the Red priority designation for the Fairchild Avenue Plume remains appropriate.
Kenney Avenue Plume: The 2007 RPO evaluation identified the Kenney Avenue Plume as a Red priority site because TCE levels in the center of the plume (403WL-01) did not appear to be decreasing at a sufficiently rapid rate to achieve site cleanup by 2025, & TCE levels at one seep at the toe of the Kenney Avenue Plume (OU5SP-10) appeared to be increasing. TCE levels at well 403WL-01 were lower in 2009 than in 2008, although TCE levels measured at seep point OU5SP-10 were relatively consistent with those detected in 2008. If another significant decrease in TCE level is seen in well 403WL-01 in 2010, a change to the priority designation for the Kenney Avenue Plume may be possible. However, at this time, the Red priority designation for the Kenney Avenue Plume remains appropriate.
As discussed in the 2007 RPO evaluation, the source area(s) for the Kenney Avenue Plume needs to be investigated, & source removal/treatment needs to be initiated if appropriate. Because of the consistently low (less than 5 ug/L of TCE) levels detected at OU5MW-36, sampling at this well should be discontinued & another well identified to facilitate assessment of temporal trends in TCE levels in groundwater. Measurement of methane & total organic carbon at 403WL-01, OU5SP-09, OU5SP-10, OU5SP-11, & a limited number of wells between 403WL-01 & Seeps 9, 10, & 11 should be considered while planning the 2010 field season. Data collected in 2010 should be evaluated to determine the appropriate frequency of biogeochemical sampling beyond 2010 at locations downgradient of the substrate injection area & whether additional treatment of the Kenney Avenue Plume source area should be considered.
Slammer Avenue Plumes: The 2007 RPO evaluation identified the Slammer Avenue Plumes as a Red priority site because the TCE levels in the eastern portion of the plume are not decreasing. TCE levels measured in OU5MW-06 & OU5MW-07 in 2009 are lower than 2008 results. TCE levels at OU5MW-06 are slowly declining over time, suggesting that natural attenuation processes will eventually cause TCE levels to decline below the cleanup level in the western Slammer Avenue Plume.
TCE levels in samples from OU5MW-07, however, are largely unchanged over time, suggesting that the eastern Slammer Avenue Plume will persist above cleanup standards well beyond the anticipated 2025 cleanup date identified in the ROD. Based on the data from OU5MW-07, the Red priority designation for the Slammer Avenue Plumes remains appropriate. As discussed in the 2007 RPO evaluation, the source area(s) for the Slammer Avenue Plumes needs to be investigated, & source removal/treatment should be initiated if appropriate.
OU3MW-25 Plume: The 2007 RPO evaluation identified the OU3MW-25 Plume as a Green priority site because the TCE level was below the cleanup level. The TCE level at well OU3MW-25 remains below the cleanup level; therefore, the Green priority designation for the OU3MW-25 plume remains appropriate. The TCE level measured in well OU3MW-25 has been below the cleanup level since 2007. A discussion with the regulators should be initiated regarding a cessation of sampling at well OU3MW-25 & a NFA determination for this plume.
OU5MW-02 Plume: The 2007 RPO evaluation identified the OU5MW-02 Plume as a Red priority site because a cleanup date cannot be predicted. TCE concentrations in wells OU3MW-02 & OU5MW-44 in 2009 were slightly lower than the 2008 levels, but remain above the cleanup level of 5 µg/L. Although the absence of a detectable TCE level at downgradient early warning well OU5MW-45 demonstrates that the OU4MW-02 Plume is not migrating off-base, the Red priority designation for the OU5MW-02 Plume remains appropriate. As discussed in the 2007 RPO evaluation, the source area(s) for the OU5MW-02 Plume should be investigated, & source removal/treatment needs to be initiated if appropriate. |
Louis Howard |
| 2/22/2010 |
CERCLA ROD Periodic Review |
Final Memorandum to.the Site File for OUs 1,2,4, and 5 received. The purpose of this Memorandum to the Site File is to present non-significant or minor changes to the Record of Decision (ROD) signed for OUs 1,2,4, and 5. The minor changes to the OUs involve clarifying how the US Air Force (USAF) intends to implement the Land Use Control (LUC) at sites LF59 (in OUI), ST41 (in OU2), FT23, SD24, SD25, SD26, SD27, SD28, SD29 (in OU4) and ST37 (in OU5). LUCs are referred to as institutional controls in the RODs.
Land Use Control Objectives: Restrict access to the contaminated groundwater throughout OU5
until cleanup levels have been achieved.
Groundwater: Institutional controls (also called LUCs) that prohibit use of the upper aquifer will ensure that people will not be exposed to contaminated groundwater until cleanup
goals are achieved. LUCs will be managed and implemented in accordance with Section 4.1 of this
memorandum to site file. The LUC boundaries are depicted in Figures 4.3 and 4.4 of this memorandum to site file.
Rationale for change: Air Force Policy (SAFflE Memo, 7 Oct 03) requires RODs to contain
details on implementation of LUCs. Section 4.1 of this document describes how LUCs will be managed, including the duration of the LUCs.
|
Louis Howard |
| 2/26/2010 |
Document, Report, or Work plan Review - other |
The Alaska Department of Environmental Conservation (ADEC) Contaminated Sites Program has received the above document [Draft Zone 3 Management Area Annual Report, February 2010 Elmendorf Air Force Base, Alaska] for review & comment on February 16, 2010. The cover letter requested comments by March 12, 2010. Below are ADEC’s comments regarding the annual report which covers various GW plumes & the following source areas (but is not limited to): LF59 (CS DB Hazard ID 642), ST37 (CS DB Hazard ID 631), ST48 (CS DB Hazard ID 1237) & ST68 (CS DB Hazard ID 2746).
3.3.3 Summary & Recommendations Page 3-7
The text states: “Because of the number of deep or submerged well screens, the presence of adequate GW elevation control in the vicinity of the Fairchild Avenue Plume should be assessed during the next RPO effort.” ADEC requests the AF discuss the significance of the monitoring wells with deep or submerged well screens for the Fairchild Plume given the main contaminants are trichloroethene (TCE) & tetrachloroethylene (PCE).
3.4.3 Summary & Recommendations Page 3-10
“Data collected in 2010 should be evaluated to determine the appropriate frequency of biogeochemical sampling beyond 2010 at locations downgradient of the substrate injection area & whether additional treatment of the Kenney Avenue Plume source area should be considered.” ADEC concurs.
3.5.3 Summary & Recommendations Page 3-14
“As discussed in the 2007 RPO evaluation, the source area(s) for the Slammer Avenue Plumes needs to be investigated, & source removal/treatment should be initiated if appropriate (USAF, 2008a).” ADEC concurs.
3.6.3 Summary Recommendations Page 3-16
“The TCE concentration measured in well OU3MW-25 has been below the cleanup level since 2007. A discussion with the regulators should be initiated regarding a cessation of sampling at well OU3MW-25 & a NFA determination for this plume.” ADEC disagrees. The RPMs will need to discuss the validity of granting a no further action designation (NFA) to a single plume within a source area (ST37) with five other GW plumes.
3.7.3 Summary & Recommendations Page 3-19
"As discussed in the 2007 RPO evaluation, the source area(s) for the OU5MW-02 Plume should be investigated, & source removal/treatment needs to be initiated if appropriate (USAF, 2008a).” ADEC concurs.
3.8.3 Summary & Recommendations Page 3-24
“As discussed in the 2007 RPO evaluation, the source area(s) for the SP1-02 Plume needs to be investigated, & source removal/treatment needs to be initiated if appropriate (USAF, 2008a).” ADEC concurs.
3.9.2.1.1 Deviations from the Work Plan Page 3-32
The text in this section does not mention the deployment of passive diffusion bag samplers at various monitoring wells for time periods longer those stated in the 2009 Zone 2 & Zone 3 Management Areas Work Plan. The 2009 work plan stated:
2.4.3.2 Early Warning & Sentry Wells
Six early warning & eleven sentry wells will be sampled semiannually in 2009 using passive diffusion bag samplers (PDBS). The PDBS will be placed in the monitoring well for at least 2 weeks prior to retrieval. The procedure for collecting samples with PDBS is described in SOP No. 13.
SOP #13 GW Sampling Page 1-31 PASSIVE DIFFUSION BAG SAMPLING
First Paragraph: The PDBs will be left in the wells for approximately two weeks & at that time will be removed & used to fill three VOA vials for each monitoring well sampled.
Second Paragraph: PDBs will remain in the well for at least 2 weeks before samples are collected.”
However, ADEC has noted in its review of the report, Appendix B-Field Notes lists monitoring wells on the Passive Diffusion Sampler Data Sheet where PDBs were placed in well after sample collection in (16 sampled in October & 1 in November) 2009 with the intent for the PDBs to be sampled at a later date in spring 2010. The rest of the PDS sampler data sheets show a similar pattern & deployment notes regarding spring 2010 sampling event for the PDBS.
ADEC does not rule out the appropriateness for deploying PDBs longer than two weeks as stated in the work plan for PDBs. However, ADEC requests the AF provide at least a 48 hour notice to ADEC when it plans to have the contractor remove those PDBs which were placed in 2009 & are scheduled for removal in spring 2010. This notice is to provide ADEC staff an opportunity to directly observe the condition of the PDBS (e.g. presence of biofilm). Additionally, ADEC requests the AF photograph the condition of each of the PDB removed from monitoring wells as part of the standard operating procedure & include these color photographs (as an appendix) with every annual report for all zones that use PDBs.
See site file for additional information. |
Louis Howard |
| 3/12/2010 |
Document, Report, or Work plan Review - other |
The following are EPA comments on the subject Report:
In General, the Report does a good job correlating sampling strategy and well maintenance with the findings of the 2007 RPO Report.
Some items less clear, are the last well survey, or screen depths and lengths. Also the use of PDB samplers needs to be consistent and there may be an issue here. All the aforementioned issues effect sample integrity and consistency and determine proper depth of a sample in the
water column.
A brief intro to each section outlining the above well info would help greatly.
It is also hoped that some of the issues raised in the last RPO Report will have been addressed by the next RPO Report; or at least an improved plan implemented so better data can be collected to improve the monitoring program.
3.3.3 Summary and Recommendations,Page 3-7 This appears to be an RPO question left unanswered; well depth and screen location, and groundwater level control.
3.4.3 Summary and Recommendation, Page 3-10 EPA agrees with this finding.
3.5.3 Summary and Recommendations, Page 3-14 EPA agrees with this finding.
3.6.3 Summary and Recommendations, Page3-16 EPA agrees with ADEC comments, we need to discuss future sampling, but an NFA is not usually granted for a partial OU.
3.7.3 Summary and Recommendations, Page3-19 EPA agrees with this finding.
3.8.3 Summary and Recommendations, Page3-24 EPA agrees with this finding.
3.9.2.1.1 Deviations from the Work Plan, Page 3-32 The issue of PDBS and the consistency of this use seems open to question.
This is a matter for further clarification.
3.10.4 Summary and Recommendations, Page 3-45 EPA agrees with this finding. |
Louis Howard |
| 4/28/2010 |
Update or Other Action |
Memorandum for ADEC. SUBJECT: Response to ADEC Comment on Draft 2009 Zone 1 Field Activities Report (Ref: ADEC Memo, 12.Mar 10)
1. This memorandum is in response to ADEC's concern as to why diesel-range organics (DRO) and gasoline-range organics (GRO) at select groundwater plumes were not sampled in 2009 as
previously agreed in a January 14, 2003 meeting.
Specifically, ADEC's comment (Attachment 1) is in reference to Section 3.7.1 Implications of Contaminant and Geochemical Monitoring, Page 3-17 of the draft 2009 Zone 1 Field Activities Report, which stated:
"The text states: When these parameters were monitored from 1999 to 2007, GRO concentrations in this monitoring well exceeded cleanup levels while DRO concentrations hovered near the cleanup level. ADEC requests the Air Force provide an explanation or a memorandum to the site file as an appendix to the document on why DRO and GRO were eliminated from the monitoring program as previously agreed to in a January 14, 2003 meeting with ADEC, USAF and EPA."
2. The analytes in question were not included in the Zone 1 groundwater monitoring program
for FY09 due to an administrative oversight.
The agreement to monitor for DRO and GRO was captured in meeting minutes (Attachment 2), not in a more formal mechanism such as a decision document or memorandum to the site file. In preparation for programming of project requirements, we reviewed the governing documents for the Zone 1 sites. None of the governing documents for Zone 1 sites identified GRO/DRO as a contaminant of concern (COC); therefore, GRO/DRO sampling was not programmed or conducted in 2009.
3. The U.S Air Force agrees with ADEC's request to continue sampling for diesel-range organics (DRO) and gasoline-range organics (GRO) for CERCLA sites with fuel-related plumes. Minutes of a 14 Jan 03 meeting with EPA, ADEC and DRS, provided with the above referenced ADEC memo, documents that the Air Force agreed to add DRO/GRO into the sampling program under the following conditions:
a. The decision will be documented in the 5-Year Review. The addition of DRO/GRO to the program should be introduced in the 5-Year Review under· mention of new issues affecting protectiveness.
b. The Air Force will NOT add DRO/GRO as a CERCLA ARAR, but will compare DRO/GRO results to ADEC cleanup levels in the annual reports and will discuss in subsequent 5-Year Reviews. The benefit of this is that if CERCLA COCs meet ARARs, the Air Force can achieve a partial delisting.
c. The Air Force will add DRO and GRO to the suite of analyses at monitoring wells associated with fuel plumes starting in 2004.
d. The Air Force will not pursue a decision document with ADEC on DRO/GRO until more data is gathered on the extent of the problem.
e. Until a decision document is signed with ADEC, GRO and DRO concentrations will be compared to ADEC regulations in 18 AAC 75 (Table C, Groundwater Cleanup Levels; 1,500 ug/L for DRO, 1,300 ug/L GRO).
f. Sampling frequency for DRO/GRO will follow the latest Decision Guide for Sampling Frequency (see 2002 Basewide Annual Report). "Immediately up gradient" means within a 2-year warning line, similar to that generated for OU5.
g. ADEC GRO/DRO criteria apply to groundwater, not to seeps which daylight as surface water. Criteria in 18 AAC 70 (TAR, TAqH) apply to surface water.
4. The fact that these analytes were not included in the Zone 1 groundwater monitoring program
for FY09 is attributed to an oversight. The USAF will add DRO/GRO into the suite of analyses
at monitoring wells associated with fuel-related plumes for Zone 1 (LF04 South and WP14) and
will prepare a memo to the site file to prevent this type of oversight from occurring in the future.
The USAF strategy will be to compare DRO/GRO and total aromatic hydrocarbon (TAH)/total
aqueous hydrocarbon (TAqH) sample results as contaminants of interest with current ADEC
regulations in 18 AAC 75 - Table C - Groundwater Cleanup Levels and 18 AAC 70 for surface
water. Should you have any questions, please feel free to contact me at (907) 552-2875.
Signed Gary Fink YF-02 Chief, Environmental Restoration. |
Louis Howard |
| 5/28/2010 |
Update or Other Action |
Work Plan for ST37 TCE Plume and Source Area Investigation received. The purpose of this project is to address TCE plumes at ST37 that are exhibiting slower-than-anticipated natural attenuation rates, as specified in the ROD. It has been determined that additional information is required to evaluate the plumes, including further defining the extent of the plumes and identifying potential TCE sources of the plumes themselves. The TCE-specific cleanup level in the ROD is 5 micrograms per liter (µg/L) (USAF, February 1995).
Specific study objectives for the project include the following:
• Objective 1: Confirm or re-delineate laterally and vertically all plumes identified in Section 1.2.1 to a TCE concentration of 5 µg/L.
• Objective 2: Identify source area(s) for each plume and complete a preliminary review of technologies for addressing identified TCE sources.
• Objective 3: Propose locations for new monitoring wells and abandonment of non-useful wells, as appropriate, to optimize the groundwater monitoring network.
|
Louis Howard |
| 6/21/2010 |
Document, Report, or Work plan Review - other |
Staff reviewed and commented on the Draft Work Plan ST37 TCE Plume and Source Area Investigation May 2010.
Table 3-2 Groundwater Project Screening Levels
While the target analyte is TCE,ADEC requests the Air Force report in the text of the document exceedances of chlorinated solvents expected from daughter products of TCE (presumed to be a part of natural attenuation: cis-1,2 DCE, trans-1,2 DCE, vinyl chloride) and possible parent compounds of TCE (PCE and 1,1,2,2-Tetrachloroethane).
The table does not list a screening level for the following analytes detected by EPA Method SW8260B which do in fact have cleanup levels in 18 AAC 75 Table C (amended through October 9, 2008). Where there are no MCLs or Table C cleanup levels, ADEC requests the Air Force consider using the United States Environmental Protection Agency Regions 3, 6, and 9. Regional Screening Levels for Chemical Contaminants at Superfund Sites. http://www.epa.gov/reg3hwmd/risk/human/rb-concentration_table/index.htm as screening levels. These levels correspond to a 1 x 10-6 risk level for carcinogens or an HQ of 1 for noncarcinogens.
ADEC requests the Air Force report any exceedances of the non-OU5 ROD analytes in an appendix to the report with the well ID, field sample ID, analytical method, screening level, source of screening level and then the exceedance in bold type for follow up at a later date by ADEC if and when the OU5 ROD contaminants of concern reach cleanup levels
|
Louis Howard |
| 11/17/2010 |
Meeting or Teleconference Held |
A meeting of the remedial project managers (RPMs) convened at 0900 on 17 November 10 at
the Joint Base Elmendorf-Richardson (JBER)-Richardson Conference Room in Building 658.
Attendees included: Mr. Bill Adams - Environmental Protection Agency (EPA); Mr. Louis
Howard - Alaska Department of Environmental Conservation (ADEC); Mr. Robert Shirley - Air
Force Center for Engineering and Environment (AFCEE) Western Region Environmental Office;
Mr. Nick Muszynski - AFCEE Restoration - Program Management Office (R-PMO); Mr. Rafael
Vazquez - AFCEE R-PMO; Mr. Jim Klasen - lith Air Force Environmental Attorney;
Ms. Renee Wright - Environmental Restoration Community Relations Coordinator; and CEANR
personnel - Mr. Gary Fink, Mr. Mark Prieksat, Ms. Donna Bawnler, Mr. Don Aide, Mr. Tim
Plucinski, Mr. Dick Nenahlo, and Ms. Cynthia Tomlinson.
ST37 Wetland Remediation System Optimization Study - Ms. Baumler has recently received the technical memorandum describing the findings and recommendations for future operations, maintenance and monitoring at the Wetland Remediation System. A Memorandum to the Site File for OU5 is being prepared to formally change operation of the Wetland Remediation System from a pump-based treatment system to a passive treatment system. The draft memo. is expected to. be available fo.r review fro.m 24 Jan - 24 Feb II. The final OU5 Memorandum to the Site File is anticipated to be available for signatures on 15 Mar 11.
ST37 Plume and Source Investigation - Ms. Baumler explained that a project to investigate several groundwater plumes within ST37 and attempt to identify the source of chlorinated solvents began this summer. Field work consisted of advancing 47 soil borings (30 - Fairchild Plume, 6 - Kenney Plume, and 11 - Slammer Plume) and collection of groundwater samples at 2 depths.(shallow/deep) from each boring. The drilling method was changed from direct push to rotary because of shallow refusal, which in time, produced 51 drums of soil cuttings. Eighteen drums of soil cuttings were disposed of as hazardous waste (10 - trichloroethene [TCE] and 8 - methylene chloride) at an EPA-approved facility outside of Alaska. Only 2 rounds of samples were completed, no effort was available to complete Round 3 because of the unexpected production of soil cuttings (due to the change in drilling methods). A draft field activities report is expected on 13 Dec 10. No final document anticipated at this time. |
Louis Howard |
| 2/10/2011 |
Update or Other Action |
Staff received the Draft Zone 3 Mgt. Area Annual Report. TCE levels measured in samples from wells OU3MW-11 (20 ug/L), OU5MW-34 (40 ug/L), & OU5MW-38 (12 ug/L) exceeded the GW cleanup level of 5 ug/L. TCE was not detected downgradient of the plume at wells OU5MW-43 or OU5MW-46, & no other VOCs were detected above the cleanup levels identified in the OU 5 ROD. Tetrachloroethylene (PCE) levels in the 2009 samples from well OU3MW-11 (6.0 & 5.9J ug/L [duplicate samples]) were above the cleanup level of 5 ug/L. PCE levels measured in the 2010 sample from well OU3MW-11 (2.2 30 ug/L) were below the cleanup level.
Historical biogeochemical indicator parameters measured in samples from “deep” monitoring wells at the Fairchild Avenue Plume indicate that conditions vary from an anaerobic (reducing) environment near the former source areas to mildly oxidizing (aerobic) conditions at downgradient locations. Available 2010 data for “deep” wells located within the plume (wells OU3MW-11, OU5MW-34, & OU5MW-38) are consistent with historical data.
The biogeochemical environment observed in the downgradient “deep” well outside of the plume, well OU5MW-46, was weakly reducing (anaerobic). Weakly oxidizing conditions were observed in the one “shallow” well (OU5MW-43) sampled in 2010, which is downgradient of the plume boundary. the attainment of cleanup goals at this site will likely occur primarily as a result of other natural attenuation mechanisms including dispersion, adsorption, & dilution.
The 2007 RPO evaluation identified the Fairchild Avenue Plume as a Red priority site because TCE concentrations in deeper, downgradient wells OU5MW-34 & OU5MW-38 were not decreasing, & therefore a cleanup date could not be predicted. TCE levels at these two wells in 2010 were similar to 2009 levels. Levels at OU3MW-11, which is closer to the source area, were lower than 2009 levels but were still above the cleanup level of 5 ug/L. Because a decreasing trend is still not evident for OU5MW-38, the Red priority designation for the Fairchild Avenue Plume remains appropriate.
As discussed in the 2007 RPO evaluation, the source area(s) for the Fairchild Avenue Plume needs to be investigated, & source removal/treatment should be initiated if appropriate. Additional discrete GW samples were collected during the 2010 field season as part of a study performed to evaluate the current horizontal & vertical extents of individual plumes within Site ST37. The results of this study will be reported in 2011.
The absence of monitoring wells located west of the Fairchild Avenue Plume & screened across the water table limits interpretation of regional water table elevation contours near & to the west of the Fairchild Avenue Plume. The absence of water table elevation data west of the Fairchild Avenue Plume should be assessed as part of the next RPO effort.
The 2007 RPO evaluation identified the Kenney Avenue Plume as a Red priority site because TCE levels in the center of the plume (403WL-01) did not appear to be decreasing at a sufficiently rapid rate to achieve site cleanup by 2025, & TCE levels at one seep at the toe of the Kenney Avenue Plume (seep OU5SP-10) appeared to be increasing. TCE levels at well 403WL-01 were slightly lower in 2010 than in 2009, while TCE levels measured at seep OU5SP-10 were similar to those measured in 2009. The decrease in TCE level measured in well 403WL-01 between 2009 & 2010 was not significant enough to predict a cleanup date prior to 2025. Therefore, at this time, the Red priority designation for the Kenney Avenue Plume remains appropriate.
As discussed in the 2007 RPO evaluation, the source area(s) for the Kenney Avenue Plume needs to be investigated, & source removal/treatment needs to be initiated if appropriate. If the results of a source area investigation performed in 2010 identify TCE levels that are upgradient of the treatability study area & that are as high or higher than levels in well 403WL-01, addition of a new or existing well to the Kenney Avenue monitoring program should be considered to evaluate temporal trends in TCE levels in GW that is unaffected by the treatability study. Because of the consistently low (less than 5 ug/L of TCE) levels detected historically at OU5MW-36, sampling at this well was discontinued following the 2009 monitoring event.
Measurement of methane & total organic carbon at well 403WL-01; seeps OU5SP-09, OU5SP-10, & OU5SP-11; & a limited number of wells between well 403WL-01 & the downgradient seeps should be considered while planning the 2011 field season. Data collected in 2011 should be evaluated to determine the appropriate frequency of biogeochemical sampling beyond 2011 at locations downgradient of the substrate injection area, & whether additional treatment of the Kenney Avenue Plume source area should be considered.
See site file for additional information. |
Louis Howard |
| 2/24/2011 |
Document, Report, or Work plan Review - other |
Staff reviewed and approved the recommendations in the draft annual report for source areas (Fairchild Plume, Kenney Avenue Plume, Slammer Avenue Plume, OU3MW-25 Plume, OU5MW-02 and SP1-02 Plume in Operable Unit 5. Staff also concurred with the recommendations in this section for the seeps, surface water and the future operation, maintenance and monitoring of the Wetland Remediation System. Finally, staff concurred with the recommendations for the Early Warning and Sentry wells in Operable Unit 5. |
Louis Howard |
| 4/26/2011 |
Update or Other Action |
draft Operable Unit (OU) 5 Memorandum to the Site File received. This memorandum documents performance optimization of the OU5 Wetland Remediation System. The purpose of this document (Memorandum to the Site File) is to present a non-significant or minor change to the Record of Decision (ROD) signed for Operable Unit (OU) 5. The minor change to the OU5 ROD involves performance optimization of the groundwater remedy by modifying the functional specifications for seep water treatment. This Memorandum to the Site File documents this performance optimization effort. Other components to the selected remedy for OU5 will not be affected by this minor change.
Institutional controls (also called LUCs) that prohibit use of the upper aquifer will ensure that people will not be exposed to contaminated groundwater until cleanup goals are achieved. LUCs will be managed and implemented in accordance with Section 4.1 of the OUs 1, 2, 4, and
5 Land Use Controls Memorandum to the Site File. The LUC boundary for OU5 is depicted in
Figure 4.5 of the OUs 1, 2, 4, and 5 Land Use Controls Memorandum to the Site File.
Rationale for Change: This administrative change corrects the figure reference for the OU5 LUC boundary in the OUs 1, 2, 4, and 5 Land Use Controls Memorandum to the Site File.
Seep water will continue to be passively extracted from areas of contamination along the western
and central bluffs. Extracted seep water will either be drained directly to the constructed wetland or treated within the seep collection area where it is extracted. Enhanced natural chemical, physical and biological processes will reduce contamination below cleanup levels. Baffles will be installed to control flow of water and maintain retention time, and native vegetation will be put in place to help degrade contaminants.
Rationale for Change: New technical information indicates that natural processes are reducing contaminant concentrations in the seep collection area for Pump Station 1 prior to being drained
to the constructed wetlands. Allowing treatment to take place in this seep collection area eliminates the need to pump seep water to the constructed wetlands. Removing pumping eliminates
the need for external power to the system (which increases system reliably and reduces carbon emissions) while minimizing operational costs with no adverse impact to remedy performance.
Water will be monitored near the exit of the constructed wetland and the Pump Station 1 seep collection area to ensure that the passive treatment systems are reducing concentrations below Alaska water quality standards.
Rationale for Change: Monitoring will document that the concentrations of COCs in all water exiting the wetland remediation system are below Alaska water quality standards prior to reaching Ship Creek.
This change to the OU5 ROD does not significantly change or fundamentally affect the remedy selected in the ROD; therefore, no public comment is required. |
Louis Howard |
| 5/5/2011 |
Document, Report, or Work plan Review - other |
Staff reviewed and approved the OU 5 ST37 Memorandum to the Site File dated April 26, 2011 JBER, Alaska. ADEC concurs that the minor change to the OU5 ROD documents for optimizing performance of the groundwater remedy by a non-significant modification of the functional specification for seep water treatment meets the requirements for a Non-significant or Minor Change. The change will not have a significant impact on the scope, performance or cost of the remedy. ADEC has reviewed the memorandum to the site file and will approve the document as submitted, pending any EPA comments |
Louis Howard |
| 5/19/2011 |
Update or Other Action |
Wing Instruction 32-7003 dated May 19, 2011 Land Use Control Management. OPR: 673 CES/CEANR Certified by: 673 CEG/CC (Col Russell R. Hula). This instruction implements AFPD 32-70, Environmental Quality, & is used in conjunction with AFIs 32-7020, The ERP, 32-7066, Environmental Baseline Surveys in Real Estate Transactions, & 673ABWI 32-1007, Safeguarding Utilities From Damage.
It prescribes the processes & responsibilities for the management of & compliance with land use controls on Joint Base Elmendorf-Richardson (JBER) & applies to all military & civilian organizations that occupy facilities, or conduct business, on the installation. This publication does not apply to the USAF Reserve or Air NG units & members. The current land use control areas can be found on the Environmental Restoration map located on the GeoBase webpage.
General:
1.1. Land use controls (LUC), such as limitations on access, water use, excavations, & property transfers, will supplement engineering controls as appropriate for short-term & long-term mgt to prevent or limit human & environmental exposure to hazardous substances, pollutants, or contaminants.
Examples include limitations on the depth & location of excavations, prohibition of or restrictions on well drilling & use of GW, mgt. of excavated soils, & prohibition of certain land uses. LUCs, often used interchangeably with (ICs), are administrative, procedural, engineering, & regulatory measures to control human access to & use of property.
1.2. LUCs were established at JBER to prevent exposure to contaminated soil & water, based on agreements between the military services & the EPA & the ADEC. LUCs are used to reduce the potential for exposure to hazardous substances or to enhance the protectiveness of a soil &/or water cleanup remedy. They include restrictions on the use of portions of the shallow aquifer south of the Elmendorf Moraine, limitations on the types of buildings allowed in certain areas – primarily occupancy limitations, & land use designations for certain areas as recreational use only.
The LUCs have been implemented at several sites & operable units (OU) as part of the ERP. LUCs were established for DP98 & OUs 1, 2, 4, 5, & 6 on former Elmendorf AFB property in their respective records of decision (ROD), as a component of the selected cleanup remedy. LUCs were also established for restoration & compliance sites formerly part of Fort Richardson in their respective RODs or Decision Documents. LUCs must be in place as long as a property is not available for UU or UE & may include temporary or permanent restrictions or requirements. When all cleanup goals have been achieved for a given site, temporary controls, such as GW use restrictions, may be removed.
2. Responsibilities:
2.1. JBER personnel, tenants, or contractors whose projects or activities require excavation in areas where site-specific LUCs are in effect will comply with all LUCs, 673ABWI 32-1007, & applicable AF instructions. Base contractors & tenant organizations will have LUC compliance requirements incorporated into their contracts & interagency agreements, as will be necessary. Failure to comply with LUCs will be grounds for penalty, in accordance with provisions specified in applicable contract documents. At project completion, the JBER organization or contractor will sign a certification of LUC compliance & return the compliance statement to 673 CES/CEANR.
2.2. The 673d Civil Engineer Squadron (673 CES):
2.2.1. Asset Management Flight (673 CES/CEA):
2.2.1.1. Natural Resources Management (673 CES/CEAN):
2.2.1.1.1. Environmental Restoration (673 CES/CEANR):
2.2.1.1.1.1. Will provide GW & site-specific LUC requirements throughout the installation & identify any known soil contaminated sites & monitoring wells for the area of the proposed project.
2.2.1.1.1.2. Will conduct annual site visits to ensure compliance with LUCs during project implementation.
2.2.1.1.1.3. Will conduct 5-year reviews, at 5-year intervals, or as required by any subsequent RODs.
2.2.1.1.1.4. Will prepare annual LUC compliance reports & submit reports to ADEC & USEPA by 1 February each year.
2.2.1.1.1.5. Will disseminate LUC information to personnel involved in LUC mgt, including real property & 673 CES/CEPT for inclusion into GeoBase.
2.2.1.1.1.6. Will operate an active educational program that includes disseminating updated fact sheets & LUC information, providing notices through the installation intranet & the Arctic Warrior newspaper, & by briefing LUC mgt at project kick-off meetings; Environmental, Safety & Occupational Health Council meetings, & CEB meetings.
2.2.1.1.1.7. Will coordinate any changes in the base general plan (BGP), or real estate transactions, with USEPA & ADEC.
2.2.1.1.1.8. Will maintain copies of signed certificates of compliance, indicating requestor’s adherence to LUCs during project execution.
See site file for additional information. |
Louis Howard |
| 6/1/2011 |
Update or Other Action |
Final Memo to the Site File signed. The purpose of this document (Memorandum to the Site File) is to present a non-significant or minor change to the Record of Decision (ROD) signed for Operable Unit (OU) 5. The minor change to the OU5 ROD involves performance optimization of the groundwater remedy by modifying the functional specifications for seep water treatment. This Memorandum to the Site File documents this performance optimization effort. Other components to the selected remedy for OU5 will not be affected by this minor change.
Institutional controls (also called LUCs) that prohibit use of the upper aquifer will ensure that people will not be exposed to contaminated groundwater until cleanup goals are achieved.
LUCs will be managed and implemented in accordance with Section 4.1 of the OUs 1, 2, 4, and
5 Land Use Controls Memorandum to the Site File. The LUC boundary for OU5 is depicted in
Figure 4.5 of the OUs 1, 2, 4, and 5 Land Use Controls Memorandum to the Site File.
Seep water will continue to be passively extracted from areas of contamination along the western
and central bluffs. Extracted seep water will either be drained directly to the constructed wetland or treated within the seep collection area where it is extracted. Enhanced natural chemical, physical and biological processes will reduce contamination below cleanup levels. Baffles will be installed to control flow of water and maintain retention time, and native vegetation will be put in place to help degrade contaminants.
Water will be monitored near the exit of the constructed wetland and the Pump Station 1 seep collection area to ensure that the passive treatment systems are reducing concentrations below Alaska water quality standards.
This change to the OU5 ROD does not significantly change or fundamentally affect the remedy selected in the ROD; therefore, no public comment is required. |
Louis Howard |
| 7/15/2011 |
Update or Other Action |
Quality Program Plan for Evaluating Ship Creek Hydrology near Site LF59 & Optimizing Early Warning/Sentry Wells. This work plan describes tasks that will be performed in 2011 & 2012 to 1) evaluate Ship Creek hydrology near Site LF59, & 2) optimize the long-term monitoring program for early warning/sentry wells at Joint Base Elmendorf-Richardson (JBER), Alaska.
The early warning/sentry wells at JBER are part of the long-term monitoring program for OU5. The early warning well network consists of six wells & was established in 2001 to monitor groundwater quality downgradient of existing contaminant plumes within this OU. The sentry well network consists of 11 wells located downgradient of the early warning line. The long-term monitoring objectives for early warning & sentry wells are:
-Track chlorinated volatile organic compound (VOC) concentrations in groundwater & detect any contamination above OU5 ROD-specified cleanup levels; &
-Identify if contaminant concentrations increase to levels that would potentially impact environmental receptors, such as Ship Creek.
The OU5 ROD (USAF, 1995) identified the COCs in groundwater as TCE, benzene, total fuel hydrocarbons-diesel (TFH-diesel), & TFH-gasoline. The OU5 ROD identified COCs in surface water as sheen, TFH-gasoline, & grade 4 jet fuel (JP-4). The OU 5 ROD identified TFH-diesel as the only COC for soil. In 2010, TCE was the only COC in groundwater at OU5 that did not meet an applicable cleanup goal.
A Memorandum to the Site File for OU5 that was signed in 2003 (USAF, 2003) established a monitoring frequency for early warning & sentry wells that could be either semi-annual (if upgradient plumes are stable) or annual (if upgradient plumes are unstable). Historically, VOC concentrations in early warning & sentry wells have been monitored using pump-based methods & passive diffusion bag samplers (PDBS). Over the last three years, the standard operating procedure (SOP) for long-term monitoring of early warning & sentry wells has been to deploy the samplers 1 foot above the bottom of the well. This SOP further specifies that a PDBS should remain in the well for a minimum of 2 weeks & maximum of 3 months after deployment to allow VOCs in groundwater to achieve equilibrium with water inside the PDBS.
A remedial process optimization (RPO) evaluation performed in 2007 recommended a long-term monitoring optimization study for the early warning & sentry well networks to evaluate 1) the appropriateness of continued sampling at each existing well, 2) the need for installation of new monitoring wells, & 3) the current sampling frequency (USAF, 2008b).
In addition, comments received from Alaska Department of Environmental Conservation (ADEC) on the 2009 Zone 3 Management Area Annual Report (USAF, 2010b) suggested that evaluation of 1) the potential vertical stratification of COCs in early warning & sentry wells that have screens longer than five feet, & 2) deploying PDBS longer than 3 months was merited. This work plan describes fieldwork & other data evaluation techniques that will address the recommended optimization study & ADEC concerns for early warning & sentry wells.
To achieve the project goal of optimizing the long-term monitoring program for early warning/sentry wells, the following activities will be performed:
-Collect water samples from multiple depths for monitoring wells with more than five feet of saturated thickness to evaluate vertical stratification in VOC concentrations; -Measure VOC concentrations in PDBS that have been deployed for three months & six months to evaluate if deployment length has an impact on VOC concentrations; & -Use historical data with data collected as part of this study to recommend an optimized long-term monitoring program for early warning & sentry wells in terms of location, sample interval(s), deployment duration, & frequency of sample collection.
Fieldwork to support the optimization of early warning/sentry wells will consist of the following activities:
-Measure depth to water & total depth of each early warning & sentry well;
-Deploy PDBS for evaluating vertical stratification in wells with a saturated screen thickness greater than five feet;
-Deploy PDBS for evaluating the impact of deployment duration at wells with a water columns greater than 5.5 feet; &
-Retrieve PDBS & collect water samples for analysis of VOCs by USEPA Method SW8260B in a fixed-base laboratory.
Data collected in support of optimizing the long-term monitoring program for the early warning & sentry wells at OU5 will be used to support & develop an optimized long-term monitoring program for early warning & sentry wells in terms of location, sample interval(s), deployment duration, & frequency of sample collection. |
Louis Howard |
| 8/3/2011 |
Document, Report, or Work plan Review - other |
Staff reviewed and commented on the Draft Quality Program Plan For Evaluating Ship Creek Hydrology Near Site LF59 and Optimizing Early Warning/Sentry Wells July 2011 on JBER.
28 QAPP WS #15a The Project Reporting Limit of 1.0 ug/L, the MDLs (1/2 the RL), and the Method RL 1.0 ug/L and Achievable Laboratory Limits MDLs 0.25 ug/L and RL of 1 ug/L will not meet the Table C EDB cleanup level of 0.05 ug/L. EPA 8011 or EPA 504.1 should be used when evaluating ethylene dibromide (EDB). EPA 8260 will quantify EDB in ground water; however, the detection limits do not meet theTable C cleanup level of 0.00005 mg/L
49 QAPP WS # 28A Field duplicate - Minimum of one per every ten (10) field samples for each matrix sampled, for
each target analyte (minimum of one).
|
Louis Howard |
| 10/5/2011 |
Update or Other Action |
Investigation Sampling Report for Post Road Fish Hatchery JBER-Elmendorf received. The objective of this project was to further investigate and delineate the lateral extent of petroleum hydrocarbon concentrations identified in soil and groundwater at the Post Road Fish Hatchery site during November 2007 site characterization activities (Shannon & Wilson 2007) and during 2010 construction activities.
Soil borings were advanced and groundwater grab samples were collected from temporary well points to investigate the current status of contamination and potential for contaminant migration through groundwater. One permanent groundwater well (0U5MW12) was also sampled to investigate the potential for contaminant migration from an upgradient source.
The original scope of work as proposed in the Work Plan Addendum (USAF 2011) included collecting groundwater samples from each boring location using an inertial pump (a check valve at the bottom of a sample tube). Due to high turbidity conditions, additional samples were collected from two borings (SP03 and SP04) using a peristaltic pump for comparison. Additionally, the original scope of work included a third soil boring on the northeast side, downgradient of B25. The presence of heavy utilities located both above and below the ground surface as well as in the roadway prevented the advancement of a boring in this area.
In April 2011, seven soil borings were advanced on the hatchery site. Three soil borings (BH01, BH02, and BH03) were advanced downgradient of the 2007 surface sample location (B26) in the southwestern section of the site.
Borings were advanced to 10 feet bgs with the exception of BH01, which was advanced to 15 feet bgs. Groundwater was encountered between 6 to 9 feet bgs at all soil boring locations. Soil samples were field screened for total petroleum hydrocarbons using PetroFLAG® at a frequency of one sample per 5 feet of continuous-core boring advanced with the exception of soil borings BH03 and BH05, which were screened twice at the 0- to 5-feet bgs interval.
One DRO result for Sample FH-BH04A-6-6.5-SO exceeded the ADEC cleanup level of 250 mg/kg at 3,200 mg/kg. This sample was collected from the interval between 6 and 6.5 feet bgs, which is just above the groundwater interface. All other analytical results for samples collected from this boring and the other six borings were below ADEC cleanup levels and U.S. Environmental Protection Agency (EPA) regional screening levels.
Analytical samples for groundwater were analyzed for DRO, BTEX, and PAHs. Sample FH-SPO4A-WG-IP exceeded ADEC Table C cleanup criteria for DRO, PAHs, and TAqH. 160 mg/L DRO (1.5 mg/L), 0.0063 mg/L benzo(a)anthracene (0.0012 mg/L), 0.003 m/L benzo(a)pyrene (0.0002 mg/L), 0.0055 benzo(b)fluoranthene (0.0012 mg/L), 0.00036 mg/L dibenzo(a,h)anthracene (0.0012 mg/L), and TAqH 0.096 mg/L (0.015 mg/L).
This sample was collected using the inertial pump. A second primary sample was collected using a peristaltic pump instead of an inertial pump for comparative reasons (due to high turbidity). Analytical results from the sample collected using the peristaltic pump did not exceed ADEC cleanup methods.
Analytical results for the 2011 Post Road Fish Hatchery sample investigation confirm DRO contamination above ADEC cleanup criteria at soil boring BH04, which is located in the northeastern portion of the site. In addition, concentrations of DRO, PAH, and TAqH at this location exceeded the ADEC Table C criteria for groundwater in a turbid grab sample. The less turbid peristaltic sample did not exceed groundwater or surface water criteria. DRO levels in soil and groundwater above ADEC cleanup criteria had been previously documented at the area near BH04.
Based on these results and the history of contamination in the general vicinity, groundwater impacts may be present; however, groundwater analytical results are confounded by turbidity in the sample. As such, the recommended remedial action for the contaminated soil at the Fish hatchery is monitored natural attenuation and annual groundwater sampling. One permanent monitoring well should be installed at the location of BH04, and a second should be installed hydraulically downgradient adjacent to Ship Creek to further determine the degree and extent of potential groundwater impacts. |
Louis Howard |
| 10/26/2011 |
Update or Other Action |
ST37 TCE Plume & Source Area Investigation Report draft final received. The purpose of this project is to access seven TCE plumes at ST37 that are exhibiting natural attenuation rates that are slower than the rates that were anticipated in the Operable Unit 5 ROD (1995). During preparation of this report, available chlorinated VOC data from additional sites located within or near the extent of ST37 GW contamination were evaluated. Sites included in this evaluation were Sites SD16, SD31, & SS21 of Operable Unit (OU) 3, SD30 of OU4, ST46 of OU5, & ST71.
The specific study objectives for this project are as follows:
- Objective 1: Confirm or re-delineate laterally & vertically all plumes identified in Section 1.2.3 to the cleanup level for TCE of 5 micrograms per liter (µg/L) specified in the OU5 ROD (USAF, 1995a).
- Objective 2: Identify source area(s) for each plume & complete a preliminary review of technologies for addressing identified TCE sources.
- Objective 3: Optimize the GW monitoring network by proposing locations for installation of new monitoring wells (if required) & abandonment of non-useful wells, as appropriate, to optimize the GW monitoring network.
Water levels were gauged from all existing monitoring wells during a 7-hour period. The results of this survey indicated that the depth to near the Fairchild Ave Plume & Kenney Ave Plume ranged between 12 & 32 feet bgs. Near the Slammer Ave Plume, the depth to GW was between 26 & 38 feet bgs.
Although GW levels were also collected at all direct push locations, these measurements may not have accurately reflect static GW levels across the site because 1) measurements were collected over a several-week time period, & 2) the slow recovery rate observed at many locations implies that an equilibrium static water level may not have been occurred prior to measurement. Because of this uncertainty, depth-to-water measurements at direct push sample locations were not used to produce an updated GW elevation contour map.
In 2010, TCE < 1 µg/L were measured in samples collected from two discrete sample intervals at locations SA01 & SA03. SA01 & SA03 were installed in locations that are hydraulically upgradient of the western Slammer Ave Plume. A previous report (USAF, 2009a) suggested that the source for the western Slammer Ave Plume could be near the current location of Bldg 8515, which is west of Sijan Ave. The data collected in 2010 confirm that the source area for the western Slammer Ave Plume is west of Sijan Ave.
The source area for the eastern Slammer Ave Plume remains unknown. TCE data collected in 2010 demonstrate that this plume is at least 3 times longer than previously known, with a source area in an unknown location that is NE of the North-South Runway. Because elevated TCE was observed at the furthest upgradient location sampled during the 2010 study (i.e., 21 µg/L at SA11), the upgradient extent & source area location for the eastern Slammer Ave Plume remains unknown.
Available data suggest TCE contamination from the 5 plumes listed above is comingled into a plume with multiple lobes that will be referred to as the Western ST37 Plume in the remainder of this report. The western lobe of the Western ST37 Plume generally matches the extent of the former Fairchild Ave Plume. The downgradient (southern) extent of the western lobe is defined by TCE < MDL at discrete GW sampling location FA06 (collected in 2010) & wells OU5MW-37, OU5MW-40, & OU5MW-43.
The central lobe of the Western ST37 Plume encompasses the footprints of the former OU3MW-25, OU5MW-02, & SP1-02 Plumes. Data collected from discrete GW sampling points & existing wells in 2010 identify a continuous presence of TCE contamination above 5 µg/L from the vicinity of SD16 northern, upgradient extent) to SP1-02 in the bluff area (southern, downgradient extent).
The eastern lobe of the Western ST37 Plume corresponds to the former Kenney Ave Plume. Data collected at discrete sample locations KA01 & KA02 in 2010 confirm previous interpretations (e.g., USAF, 2009c) that the source area of the former Kenney Ave Plume is west of Kenney Ave & south of Bldg 5326. The southern (downgradient) extent of this lobe extends to several seeps in the bluff area where TCE has been detected.
See site file for additional information. |
Louis Howard |
| 2/2/2012 |
Update or Other Action |
Memorandum for 2010 Annual Land Use Control (LUC) Monitoring Letter for DP98 and OUs 1, 2, 4, 5, and 6.
References:
(a) DP98 Record of Decision, Section 12.2.3.4, dated May 2004
(b) OU6 Explanation of Significant Differences, Section 4.3.1.3, dated Mar 2007
(c) Memorandum to the Site File for OUs 1,2,4, and 5, Section 4, dated Jan 2010
1. This letter serves as the annual monitoring report on the status of LUCs in place at DP98 and
at OUs 1,2,4,5 and 6. The specific LUCs in place at each site are provided below. An
evaluation of the implementation of these requirements is provided in bold following each
specific LUC.
OU5:
Site ST37
Groundwater -Institutional controls (also called LUCs) that prohibit use of the upper
aquifer will ensure that people will not be exposed to contaminated groundwater until
cleanup goals are achieved.
Evaluation - LUCs are in place and continue to be effective at ST37. A land use control inspection was accomplished in Oct 2011. The inspection forms will be presented in Appendix B of the 2011 Zones 1, 2, and 3 Mgt. Area Annual Report.
2. The Air Force ensures compliance with LUCs by conducting periodic monitoring and completing site inspections. Separate controls are in place and enforced by the Air Force to prevent inappropriate soil and groundwater exposure at these sites. The Air Force currently requires all projects resulting in soil disturbance of greater than four inches below ground surface to follow 3 Wing Instruction 32-1007, Safeguarding Utilities from Damage, dated 20 Aug 10 and 673d Wing Instruction 32-7003, Land Use control Management, dated 19 May 2011. Both instructions require the proponent to obtain an approved Base Civil Engineer Work Clearance Request (3 WG Form 3) prior to conducting work on the Base. |
Louis Howard |
| 3/16/2012 |
Update or Other Action |
Co-Occurrence of 1,4-Dioxane with Trichloroethylene in Chlorinated Solvent GW Plumes at US Air Force Installations: Fact or Fiction (Richard H Anderson,*Janet K Anderson, & Paul A Bower)
Air Force Center for Engineering & the Environment, Technical Support Division (AFCEE/TDV), 2261 Hughes, Site 155, Lackland AFB, Texas 78236, USA. Contractor, AFCEE Environmental Restoration Branch (AFCEE/ERD), Lackland AFB, Texas, USA (Submitted 22 November 2011; Returned for Revision 23 January 2012; Accepted 16 March 2012)
ABSTRACT: Increasing regulatory attention to 1,4-dioxane has prompted the United States Air Force (USAF) to evaluate potential environmental liabilities, primarily associated with legacy contamination, at an enterprise scale. Although accurately quantifying environmental liability is operationally difficult given limited historic environmental monitoring data, 1,4-dioxane is a known constituent (i.e., stabilizer) of chlorinated solvents, in particular 1,1,1-trichloroethane (TCA). Evidence regarding the co-occurrence of 1,4-dioxane & trichloroethylene (TCE), however, has been heavily debated.
In fact, the prevailing opinion is that 1,4-dioxane was not a constituent of past TCE formulations &, therefore, these 2 contaminants would not likely co-occur in the same GW plume. Because historic handling, storage, & disposal practices of chlorinated solvents have resulted in widespread GW contamination at USAF installations, significant potential exists for unidentified 1,4-dioxane contamination.
Therefore, the objective of this investigation is to determine the extent to which 1,4-dioxane co-occurs with TCE compared to TCA, & if these chemicals are co-contaminants, whether or not there is significant correlation using available monitoring data. To accomplish these objectives, the USAF Environmental Restoration Program Information Management System (ERPIMS) was queried for all relevant records for GW monitoring wells (GMWs) with 1,4-dioxane, TCA, & TCE, on which both categorical & quantitative analyses were carried out.
Overall, ERPIMS contained 5788 GMWs from 49 installations with records for 1,4-dioxane, TCE, & TCA analytes. 1,4-Dioxane was observed in 17.4% of the GMWs with detections for TCE &/or TCA, which accounted for 93.7% of all 1,4-dioxane detections, verifying that 1,4-dioxane is seldom found independent of chlorinated solvent contamination. Surprisingly, 64.4% of all 1,4-dioxane detections were associated with TCE independently. Given the extensive data set, these results conclusively demonstrate for the first time that 1,4-dioxane is a relatively common GW co-contaminant with TCE. Trend analysis demonstrated a positive log-linear relationship where median 1,4-dioxane levels increased between approximately 6% & approximately 20% of the increase in TCE levels.
In conclusion, this data mining exercise suggests that 1,4-dioxane has a probability of co-occurrence of approximately 17% with either TCE &/or TCA. Given the challenges imposed by remediation of 1,4-dioxane & the pending promulgation of a federal regulatory standard, environmental project managers should use the information presented in this article for prioritization of future characterization efforts to respond to the emerging issue. Importantly, site investigations should consider 1,4-dioxane a potential co-contaminant of TCE in GW plumes. Integr Environ Assess Manag 2012;8:731–737. |
Louis Howard |
| 4/10/2012 |
Update or Other Action |
Draft 2011 Zones 1, 2 & 3 Annual Report received. Draft 2011 Zones 1, 2, 3 Annual Report received. Two sites are monitored under the Zone 3 Management Area: Sites LF59 & ST37. GW is monitored at seven plumes within these two sites. In addition, GW, seep, & surface water are monitored at locations near the southern boundary of JBER Elmendorf, the Beaver Pond, the OU5 Engineered Wetland Remediation System, & the early warning & sentry well networks. Zone 3 also includes the operations & maintenance (O&M) of the Contractor’s Yard.
ST37 was originally one of six fuel contamination source areas investigated after a fuel line broke & released an unknown quantity of diesel. These sites were grouped together due to their proximity & similar contamination. The OU5 ROD (USAF, 1995d) specifies the selected remedy for ST37, which includes MNA & treatment of contaminated GW seeps by the Wetland Remediation System. COCs in GW, seep, & surface water include TCE & fuel constituents.
The plumes associated with Site ST37 include the Fairchild Avenue Plume, Kenney Avenue Plume, Slammer Avenue Plumes, OU3MW-25 Plume, OU5MW-02 Plume, & SP1-02 Plume. Site ST37 also includes seeps & surface water sample locations near the southern boundary of JBER-Elmendorf & the Early Warning & Sentry Well Networks.
As of December 2011, TCE was the only COC in GW at Site ST37 that did not meet its cleanup goal (5 µg/L). The ROD estimated that all GW contaminants would meet cleanup goals by 2025. Minor modifications to the ROD-specified remedy have been documented in several memorandums to the site file. The first memorandum to the site file adopted a sampling frequency decision guide (USAF, 2003e), while the second memorandum clarified how USAF intends to manage land use controls (USAF, 2011g), & the most recent memorandum to the site file documents implementation of passive operation of the wetland remediation system for seep water treatment. The second memorandum to the site file was finalized in January 2010 & the third one in June 2011.
TCE measured in samples from wells OU3MW-11 (45 J µg/L), OU5MW-34 (34 J µg/L), & OU5MW-38 (13 J µg/L) exceeded the GW cleanup level of 5 µg/L.
The 2007 RPO Evaluation Report (USAF, 2008h) identified the Fairchild 12006 Avenue Plume as a Red priority site because TCE concentrations in deeper, in-plume wells OU5MW-34 & OU5MW-38 were not decreasing, & therefore a cleanup date could not be predicted. TCE levels at these two wells in 2011 were similar to 2010 levels. Concentrations at OU3MW-11, which is closer to the source area, were higher than 2010 levels & were still above the cleanup level of 5 µg/L. Because a clear decreasing trend is still not evident for OU5MW-34 or OU5MW-38, the Red priority designation for the Fairchild Avenue Plume remains appropriate.
• As discussed in the 2007 RPO evaluation, the source area(s) for the Fairchild Avenue Plume needs to be investigated, & source removal/treatment should be initiated if appropriate (USAF, 2008h). Additional discrete GW samples were collected during the 2010 field season as part of a study performed to evaluate the current horizontal & vertical extents of individual plumes within Site ST37. The results of this study will be reported under separate cover.
• The absence of monitoring wells located west of the Fairchild Avenue Plume & screened across the water table limits the interpretation of regional water table elevation contours near & to the west of the Fairchild Avenue Plume. The absence of water table elevation data west of the Fairchild Avenue Plume was assessed in the 2011 & will be reported under separate cover. The results of this effort should be incorporated into future field activities.
The TCE concentration in 403WL-01 (23 J µg/L) exceeded the GW cleanup level of 5 µg/L.
The 2007 RPO Evaluation Report (USAF, 2008h) identified the Kenney Avenue Plume as a Red priority site because TCE levels in the center of the plume (403WL-01) did not appear to be decreasing at a sufficiently rapid rate to achieve site cleanup by 2025, & TCE levels at one seep at the toe of the Kenney Avenue Plume (seep OU5SP-10) appeared to be increasing. TCE levels at well 403WL-01 were the same in 2010 & 2011, but were slightly lower than in 2009, while TCE levels measured at seep OU5SP-10 were similar to those measured in 2010. The decrease in TCE level measured in well 403WL-01 from 2009 & 2011 was not significant enough to predict a cleanup date prior to 2025. Therefore, at this time, the Red priority designation for the Kenney Avenue Plume remains appropriate.
See site file for additional information.
|
Louis Howard |
| 3/1/2013 |
Institutional Control Update |
2012 Annual LUC IC Monitoring memorandum received.
This letter serves as the annual monitoring report on the status of LUCs in place on JBER Elmendorf at DP98 and OUs 1, 2, 4, 5 and 6. The specific LUCs in place at each site are
provided below. An evaluation of the implementation of these requirements is provided in bold
following each specific LUC.
Groundwater - Institutional controls (also called LUCs) that prohibit use of the upper aquifer will ensure that people will not be exposed to contaminated groundwater until cleanup goals are achieved.
Evaluation - Inspection conducted on 29 Aug 12 and LUCs are in place and continue to be effective at ST37. |
Louis Howard |
| 5/30/2013 |
Update or Other Action |
Draft Annual Field Activities report received for review & comment.
Fairchild Ave. Plume
During 2012, GW monitoring wells OU3MW-11, OU5MW-34, OU5MW-38 & OU5MW-46 were sampled for VOCs. Analytical results indicated TCE measured from GW monitoring wells OU3MW-11, OU5MW-34 & OU5MW38 exceeded the OU5 ROD GW cleanup criteria at levels of 48 µg/L, 40 µg/L, & 13 µg/L (respectively). No analytical results exceeded contaminant cleanup levels in the remaining well, OU5MW-46. Results for all other analytes were below cleanup criterion. A LUC inspection performed for all of ST037 on 29 August 2012 did not identify any issues.
Site Summary
Based on the 2012 GW data, wells located within the plume (wells OU3MW-11, OU5MW-34, & OU5MW-38) exceeded OU5 ROD cleanup criteria, which is consistent with historical data. Downgradient of the plume, well OU6MW-46 TCE results were below cleanup criterion. These results are consistent with historical data. No changes to the annual monitoring are being proposed for this site.
Kenney Ave. Plume
During 2012, GW monitoring well 403WL-01 & ground water seeps OU5SP-09, OU5SP-10, & OU5SP-11 were sampled for VOCs. The reported TCE in 403WL-01 (29 µg/L) & seeps OU5SP-10 (8.5 µg/L), & OU5SP-11 (9.2 µg/L) exceeded the OU5 ROD GW cleanup criterion of 5 µg/L. No other VOCs were detected above the cleanup criteria.
Site Summary
Based on the 2012 GW data, TCE in the center of the plume (403WL-01) did not appear to be decreasing at a rate sufficient to achieve site cleanup by 2025. Seep OU5SP-10 at the toe of the Kenney Ave. Plume appeared to be slightly increasing, where concentrations at OU5SP-09 appear to be decreasing. TCE at well 403WL-01 were the same from 2009 to 2011, but increased in 2012. Based on historic & current monitoring results, TCE measured in well 403WL-01 will likely not reach a cleanup date prior to 2025.
No changes to the annual monitoring are being proposed for this site.
Slammer Ave. Plume
During 2012, GW monitoring wells GW-4A, OU5MW-06, OU5MW-07 & OU5MW-08 were sampled for VOCs. The TCE in wells OU5MW-06 (15 µg/L) & OU5MW-07 (20 µg/L) exceeded the OU5 ROD GW cleanup criterion of 5 µg/L. No other VOCs were detected above the cleanup criteria.
Site Summary
TCE measured at well OU5MW-06 (15 µg/L) & well OU5MW-07 (20 µg/L) exceeded the GW cleanup criterion of 5 µg/L; these are similar to those measured at these wells from 2007 through 2011.
The TCE in the eastern portion of the plume (now the eastern Slammer Avenue Plume) were not decreasing. TCE measured in wells OU5MW-06 & OU5MW-07 in 2012 were similar to concentrations measured in these wells in 2011. TCE at well OU5MW-06 are declining over time, although it appears to be slow, suggesting that natural attenuation processes will eventually cause TCE to decline below the cleanup level in the western Slammer Ave. Plume. TCE in samples from well OU5MW-07 appear to be stable (not migrating) & are largely unchanged over time, suggesting that the eastern Slammer Ave. Plume will persist above cleanup standards beyond the anticipated 2025 cleanup date identified in the ROD (USAF, 1995c). No changes to the annual monitoring are being proposed for this site.
OU5MW-02 Plume
During 2012, GW monitoring wells OU3MW-02 & OU5MW-44 were sampled for VOCs only. Well OU5MW-45 was sampled for VOCs & SVOCs by using a passive diffusion bag sampler (PDBS). The TCE in wells OU3MW-02 (11 µg/L) & OU5MW-44 (25 µg/L) exceeded the OU5 ROD GW cleanup criterion of 5 µg/L. TCE at OU5MW-45 were below cleanup criterion for both sampling events. No other VOCs were detected above the cleanup criteria.
Site Summary
Based on 2012 analytical data, TCE in wells OU3MW-02 & OU5MW-44 were approximately the same as 2010 & 2011 concentrations & remain above the cleanup criterion of 5 µg/L. The results for TCE at downgradient early warning well OU5MW-45 demonstrates that the OU5MW-02 Plume is stable & not migrating off the installation.
No changes to the annual monitoring are being proposed for this site.
SP1-02 Plume
During 2012, GW monitoring wells SP1-02, OU5MW-15 & seep OU5SP-15 were sampled for VOCs only. Well OU5MW-45 was sampled for VOCs & SVOCs by using a PDBS. The TCE in well SP1-02 (5.4 µg/L) exceeded the OU5 ROD GW cleanup criteria of 5 µg/L. No other VOCs were detected above the cleanup criteria.
Site Summary
TCE at well SP1-02 continues to show a decreasing trend but remains just above the cleanup level of 5 µg/L. Since 2007, the TCE in well SP1-02 has significantly dropped & is expected to continue to slowly degrade over time. Downgradient well OU5MW-15 results indicate that the plume is not migrating. Well OU5MW-45 & seep OU5SP-15 results still bound the plume to the north & east.
No changes to the annual monitoring are being proposed for this site. |
Louis Howard |
| 6/28/2013 |
Document, Report, or Work plan Review - other |
Staff provided comments on draft annual field activities CERCLA report.
Comment#1
ADEC is requesting that 1,4-dioxane be sampled for in groundwater where trichloroethylene (TCE) or 1,1,1- trichloroethane (TCA) contamination exists or was previously above cleanup levels at any site (CERCLA or State restoration or compliance). Please incorporate these comments into any basewide sampling plans (current/future).
AFCEE research has found 1,4-dioxane at Air Force sites contaminated with TCE. The study, titled "Co-Occurrence of 1,4-Dioxane with Trichloroethylene in Chlorinated Solvent Groundwater Plumes at US Air Force Installations: Fact or Fiction," found detections of 1,4-dioxane at sites with TCE, independent of TCA.
"Surprisingly, 64.4% of all 1,4-dioxane detections were associated with TCE independently," the researchers say in the abstract. "Given the extensive data set, these results conclusively demonstrate for the first time that 1,4-dioxane is a relatively common groundwater co-contaminant with TCE."
The study authors recommend site investigations consider 1,4-dioxane as a potential co-contaminant of TCE at groundwater plume sites. The study, which was published in the Integrated Environmental Assessment and Management journal last year, explicitly warns that new discoveries of 1,4-dioxane contamination could delay cleanup completions and require more costly revisions to existing remedies, noting that there is strong evidence suggesting that 1,4-dioxane "will migrate much further than chlorinated solvents."
ADEC has promulgated enforceable cleanup levels (not advisories) for 1,4-Dioxane in soil and groundwater (latest version 18 AAC 75 April 2012 Table B1 and Table C) effective since 2008 which has remained unchanged in 2012 revised regulations.
Soil Under 40 inch Zone
540 mg/kg direct contact
0.21 mg/kg migration to groundwater
0.077 mg/L (77 µg/L) Table C groundwater cleanup level
This comment regarding monitoring requirements for 1,4-Dioxane applies to JBER-Elmendorf and JBER-Richardson sites with current or past TCE or TCA contamination. The monitoring requirement is also applicable to the “Early Warning and Sentry Wells” which were established to provide early detection of contaminant plumes that may impact Ship Creek or other downgradient environmental receptors.
1,4-Dioxane readily leaches to groundwater, is not expected to adsorb significantly to soil particles, and is difficult to biodegrade. Due to these properties, a 1,4-Dioxane plume typically proceeds ahead of the chlorinated solvent plume, and will tend to impact an aquifer system to a much larger extent.
Suggested laboratory methods: SW-846 Method 5030C, SW-846 Method 5021, SW-846 Method 8261A, SW-846 Method 5031, SW-846 8270C SIM, LVI and isotope dilution (1.0 µg/L or 2.0 µg/kg reporting limits). Dioxane can be detected using EPA 8260; however, its high water solubility causes relatively high reporting limits.
Routine organic extraction procedures like those traditionally used for EPA 8270 analyses produce low recoveries (approximately 50% or less). Whatever laboratory method is proposed for 1,4-Dioxane by JBER, the laboratory method must be able to detect at or below the ADEC promulgated groundwater cleanup level in Table C and migration to groundwater cleanup level in soil.
Be aware that with ADEC’s regulatory revisions in 2014, the level for 1,4-Dioxane (as well as many other compounds) will go down substantially from its current promulgated levels for soil and groundwater. These changes in regulations will be available for public comment sometime this year.
Finally, the EPA May 2013 Regional Screening Levels for tapwater lists a lower screening level of 0.67 ug/L which equates to a 1x10-6 total risk as well as a noncarcinogenic screening level of 47 µg/L which equates to a HI of 0.1.
12-4 to 12-7 ST037
Fairchild Avenue Plume
Kenney Avenue Plume
Slammer Avenue Plume
OU5MW-02 Plume
See comment #1 regarding 1,4-dioxane analysis in groundwater. This comment applies to JBER-E and JBER-E sites with current or past TCE or TCA contamination. |
Louis Howard |
| 7/3/2013 |
Document, Report, or Work plan Review - other |
EPA Sandra Halstead provided review comments on the 2013 Letter Work Plan Addendum.
1.0 Introduction
The 2012 Annual Report was not reviewed or finalized at the time of review of the draft 2013 LTM workplan. It is unknown if the tables are consistent with the recommendations. The table from 2011 was used as the basis for sampling location, COC group, and frequency.
2.1.2 LUC/IC Inspections
These site names are provided in Table 11-1 of the 2013 UFP-QAPP. It would be good to refer to that Table since some of the sites have changed names since the 2011 workplan.
Suggest using the same inspection sheet for both JBER-E and JBER-R LUC inspections. Attachment 1B provides more detailed information and is the preferred format.
2.1.3 OU5 WRS O&M
Add observer name to inspection form.
Table 1 JBER-Elmendorf CERCLA Regulated Sites
What happened to well OU6MW-67? It was on a 2 year frequency for VOCs.
FT023 & SD015
Well FP56 missing and well OU4MW-11 was not in the 2011 workplan. Are these the same?
Well OU6MW-18 is missing for annual sampling for VOCs.
ST037 Seeps
2011 Workplan lists BTEX as a constituent, not PAH for the Seeps.
Pump Stn #1, Ship Cr., Beaver Pond Area
2011 workplan included BTEX analysis for Pump Station #1, Ship Creek, Beaver Pond, and Wetland Treatment Cell samples.
Wetland Treatment Cell
No PAH in 2011 workplan; please make sure a sample is taken without MeOH preservative for SW8260 for soils/sediment. |
Louis Howard |
| 11/4/2013 |
Update or Other Action |
Fourth Five-Year Review (draft) received for review & comment.
One of the key findings from the 2010 plume & source area groundwater investigation was that the northern portion of the Fairchild Avenue Plume, the OU3MW-25 Plume, & the OU5MW-02 Plume may all be part of a larger, singular plume (the Fairchild Combined Plume). According to the investigation’s findings, the Fairchild Combined Plume may be a result of a former disposal site previously identified near the east-west runway, north of Fighter Drive & east of Fairchild Avenue (USAF, 2011g). Based on TCE concentrations, an additional source area may also be present in the vicinity of monitoring well 402WL-02.
The plume & source area groundwater investigation report also suggested that based on TCE concentrations, the southern portion of the Fairchild Avenue Plume is the result of a separate source area, most likely located in the vicinity of Building 6211. The ST37 TCE Plume & Source Area Investigation (USAF, 2011a) helped to further delineate the potential source areas contributing to the TCE contamination identified in the groundwater at ST37; however, the exact locations of the sources areas still remain undetermined. If they can be identified, treatment of source areas offers the best opportunity to accelerate attainment of cleanup levels for OU5 plumes.
Given that TCE concentrations in OU5 plumes are low (relative to solubility) & spread over a large area, identifying the source areas may prove difficult. Monitoring results at OU5 indicate that natural attenuation remedies are generally decreasing COC concentrations. However, the process is slower than anticipated in the ROD, & it is unlikely that concentrations of COCs will fall below their respective cleanup levels prior to the ROD-specified cleanup date (2025).
Early warning & sentry wells are monitored to indicate if contaminants are migrating offsite toward Ship Creek. Monitoring of early warning wells was initiated to provide sufficiently early indication of contaminant migration so that contingency actions, if necessary, could be programmed & implemented prior to contaminants reaching Ship Creek. A portion of the early warning/sentry wells are located in areas that are not downgradient of any known plumes & samples collected from these wells have consistently exhibited non-detectable concentrations of COCs. Because these wells are not located downgradient of an identified plume, they do not serve their intended purpose. Optimization of the early warning & sentry monitoring well system to eliminate unnecessary wells would reduce monitoring costs.
Recommendations & follow-up: Define the source(s) of contamination in seeps OU5SP-01 & OU5SP-02. Use investigation results to determine if source area treatment is a feasible & appropriate approach for reducing or eliminating COC concentrations in seeps that flow into the Pump Station #1 seep collection area. A comprehensive vapor intrusion study, especially in terms of residential occupancy exposure, should be conducted for all manned facilities potentially affected by the TCE plumes in OU5. Continue to further delineate the potential source areas at OU5 & evaluate alternative remedial strategies to accelerate attainment of cleanup levels in groundwater,
Protectiveness: Protectiveness determination of the remedy at OU5 is deferred until the potential impacts associated with the vapor intrusion pathway at the site are evaluated. The vapor intrusion assessment is expected to be performed in 2014.
The Future Five-Year Reviews for OUs 1, 2, 4, 5 & 6 & Site DP98 are necessary because contamination remains above levels that allow for UU/UE in these areas. The next Five-Year Review is due on or before January 27, 2019.
|
Louis Howard |
| 12/20/2013 |
Document, Report, or Work plan Review - other |
Staff provided comments on the draft 4th 5 Year Review report.
4-28 4.4.1 Operable Unit 5 Remedy Implementation & Status
1,4-dioxane analysis in GW is required for sites with current or past TCE or TCA contamination. TCE was identified as a contaminant present in water most likely present due to past disposal practices at OU 5 or upgradient sources.
The purpose of the early warning & sentry wells are not just for OU 5 ROD COCs but from upgradient contaminant plumes not found in OU 5 & source areas not listed in the OU 5 ROD including identified & unidentified petroleum source areas.
As stated in this section on Page 4-28:
“The early warning well network at OU5 was established in 2001 to provide early detection of contaminant plumes that may impact Ship Creek or other downgradient environmental receptors. The monitoring activities for the early warning & sentry wells are intended to track chlorinated VOC concentrations in GW, detect any contamination above OU5 ROD specified cleanup levels (5 µg/L for TCE), & determine if contaminant concentrations increase to levels that might potentially affect environmental receptors, such as Ship Creek.”
March 26, 1993 Basewide GW memorandum of agreement between USAF, USEPA & ADEC indicated that any GW contamination from upgradient of OU5 would be dealt by OU5 regardless of CERCLA or POL source areas & not be limited to COCs identified specifically in OU5 Record of Decision.
“As a result of the basewide GW study & the FY92 field work that occurred at Operable Units (OUs) 1, 2, & 5 it appears that a large portion of the GW flows into OU5 (Atch 1). Based on this information Elmendorf AFB would like to move all upgradient GW into the OU5 Feasibility Study, Proposed Plan & Record of Decison. This means we would address all GW from upgradient sources (CERCLA (ST20, OU3, & OU4) & SERA) at OU5 instead of at each individual source area (Atch 2).”
Therefore, the list of COCs & COPCs analyzed for in GW at OU5 must be increased & encompass those releases from upgradient CERCLA & petroleum (both UST & non-UST) source areas.
Operable Unit 5
Page 7-18
Changes in Toxicity & Other Contaminant Characteristics
Operable Unit 5
Please reference the sources for the updated chemical-specific toxicity information for the OU5 COC (TCE).
9.0 Table 9-1
OU4, OU5, DP-98
There is no description here or in the text of the document on the exact number of occupied facilities or manned facilities that are in proximity to VOC GW plumes or potential affected by the TCE plumes. A general idea of the number of facilities will help determine the scope of the vapor intrusion assessment required at each of these facilities before 12/31/2016. ADEC requests either here or in the text of the document a description be added detailing the number of facilities expected to be assessed. OU6 SD15 & OU1 need to be added to the table if there are manned/occupied facilities present in proximity to the TCE plume at LF059 & SD15.
Page 214
OU5
GW
Fuel contaminated GW was detected during the 1994 RI/FS. While not specifically detailed as DRO (C10-C25) or GRO (C6-C10), the 1994 investigation used TVHC or total volatile hydrocarbons to estimate fuels contamination. The TVHCs C4-9 [automotive gasoline] were quantified by integrating the peaks for compounds containing four carbon atoms through o-xylene. The TVHCs C10-X [diesel fuel] quantification began after o-xylene, and the endpoints varied with the sample run times. The TVHC results should be considered estimates of fuel contamination because quantitations were based on estimates of both retention times and response factors for fuel hydrocarbons (2.1.2.3 Page 121 of the 1994 RI).
A few of the groundwater exceedances for GRO/DRO from the 1994 RI (there are many more but this demonstrated that GRO and DRO in GW was present above applicable cleanup levels during the RI):
TVHC C4-9 [corresponds to GRO] and TVHC C10-X [corresponds to DRO]
Page 375 of the 1994 RI
OU5GW18-4 TVHC C4-9: 6.6 mg/L
Page 377 of the 1994 RI
OU5GW27-4 TVHC C10-X: 5.2 mg/L and TVHC C4-9: 210 mg/L
OU5GW28-4 TVHC C4-9: 4.8 mg/L
Page 379
OU5GW36-3 TVHC C4-9: 12 mg/L
OU5GW37-5 TVHC C4-9: 3.5 mg/L
Page 384
OU5GW61-3 TVHC C10-X: 4.3 mg/L and TVHC C4-9: 30 mg/L
OU5GW62-3 TVHC C10-X: 1.8 mgL and TVHC C4-9 15 mg/L
OU5GW63-3 TVHC C4-9: 7.5 mg/L
Page 385
OU5SL01-2 TVHC C10-X: 11 mg/L (Highest detection of DRO)
OUS5L02-2 TVHC C10-X: 3.9 mg/L and TVHC C4-9: 91 mg/L
OU5SL03-2 TVHC C10-X: 8 mg/L and TVHC C4-9: 1.9 mg/L
OU5SL04-2 TVHC C10-X: 2.7 mg/L and TVHC C4-9 4.1 mg/L
OU5SL 05-3 TVHC C4-9: 3.4 mg/L
Page 386
OU5SL09-4 TVHC C10-X: 1.4 mg/L and TVHC C4-9 9.2 mg/L
OU5SL11-4 TVHC C10-X: 6.2 mg/L and TVHC C4-9 9.1 mg/L
Highest detected TVHC4-9 (comparable to Gasoline Range Organics) in groundwater was found at OU5SL23-3 510 mg/L.
|
Louis Howard |
| 12/30/2013 |
Document, Report, or Work plan Review - other |
EPA comments on the draft 4th 5 Year Review report.
Draft Reference Documents Comment: Two key references are still in draft form (USAF 2011g & USAF 2013). Given these documents have not been approved by the regulators, please clarify the applicability of the information to inclusion in the report. If this information is retained, clarify these are preliminary or draft results in both the text narrative & figures.
In addition to the 2012 Annual Report still in draft form, some of the site-specific figures contained in Appendix C show “pending” for fourth quarter 2012 results; however, fourth quarter samples should have been collected a year ago, so it is unclear why no data have been presented. For example, on Figure C-14 the fourth quarter 2012 result for seep OU5SP-02 is listed as “pending.” Please revise the site-specific figures contained in Appendix C to include results from the fourth quarter 2012 sampling or provide an explanation as to why those data are pending & clarify all 2012 data are draft until the 2012 Annual Monitoring Report is finalized.
Remedial Alternative Evaluations Comment: Please clarify the process under CERLCA for implementing the recommendations at OU4 & OU5 “evaluate alternative remedial strategies”; OU6 “perform remedial process optimization”; & DP98 “evaluate the applicability of increasing the scale of pilot tests to improve remedy performance”. Do the terms imply the RI/FS for these sites will be reopened? Please clarify the Air Force will conduct the evaluation in conjunction with the ADEC & EPA & any new remedies will require approval from the regulators.
Draft FYR O&M Comment: None of the OU-specific/site-specific operations & maintenance (O&M) discussions or Appendix H summarize the cost associated with O&M during the period under review (2009 through 2013) & provide only O&M costs prior through the last 5 year review (2007). For example, for OU5, the conversion of the wetland remediation system from an active pumping system to passive system is claimed to be cost effective however no data to support this claim is provided. Please expand the OU-specific/site-specific O&M discussions to include not only cost summaries, but also an overview of activities that took place during the period under review (modifications, problems, successes, etc.) & costs associated during this review period. If information on O&M is not available for this review period, please provide rationale for its absence from the report & modify the Appendix H totals to clarify the total cost is calculated through 2007.
OU5: ST-37 (Fairchild Ave, Kenney Ave, & Slammer Ave plumes): There is some apparent MNA of these TCE plumes, but it's not terribly convincing in that it's not happening in all wells throughout the plumes. In general the plumes are not well characterized -- sources are not convincingly located/monitored & the leading edges are not identified & monitored for trends (the "early warning" wells are much too far downgradient of the plumes' mapped extents). The report defers protectiveness, & calls for VI investigations, but that's hard to do convincingly if the plume extents aren't well mapped out. In particular, note that part of the Fairchild Ave. plume at ~45 ppb flows under what appears to be housing.
Summary Form OU5 Remedy Performance Page S-4 Comment: The report contained almost identical language for the slow degradation of GW COCs at OU5 plumes & had a milestone date of 2013. Work was conducted on ST37 TCE Plumes & Source Area Investigations. Please describe why further delineation is necessary given the work conducted as part of the 3rd Five Year Review (2008) to address this issue. Please describe the process under CERCLA for “evaluation of alternative remedial strategies” at a site with a signed Record of Decision were the selected remedy has been implemented.
Table 4-7 Page 4-23, Table 4-8 Page 4-24, & Section 4.4.1 Page 4-25 Lines 7-9 Comment: The text on page 4-25 states “GW, seep, surface water, & sediment monitoring is ongoing for OU5, though sediment sampling has been discontinued in all except one location due to consistent non-detect analytical results;” however, Table 4-8 does not list sediment sampling as a remedy component & Table 4-7 does not include sediment cleanup levels for OU5. Please resolve these discrepancies.
Table 4-8 Page 4-24 Observation: The WJ Hernandez, just south of the JBER boundary on the SW corner of Reese Blvd & Post Rd, uses filtered GW in their aquaculture tanks. Do the LUC prohibitions to ‘restrict access to contaminated GW throughout OU5’ apply to adjacent parcels off the base boundary?
|
Louis Howard |
| 1/3/2014 |
Document, Report, or Work plan Review - other |
EPA comments on the draft 4th 5 Year-Review report.
Summary Form pages S-2 to S-5 Comment: For the deferred protectiveness on OU4, OU5, and DP98 , it is recommended to change the current protectiveness to “No” and to establish an interim milestone date in 2014 for assessment of vapor intrusion risk in occupied residences and offices.
If data currently exists that suggests this is a current protectiveness issue and complete pathway, then the answer can be retained as ‘yes’. Section 6.4 Data Review did not present vapor intrusion data, calculations, or assessment to be able to answer this question.
Summary Form OU4, OU5, DP98 Monitoring VI pathway Pages S-3, S-4, S-5 Comment: EPA agrees with both the issue of potential vapor intrusion and evaluation of the VI risk in these OUs, however the recommendation should spell out what is intended in the “vapor intrusion evaluations that provide multiple lines of evidence” as outlined in OU4 and DP98. OU5 recommends a “comprehensive vapor intrusion study, especially in terms of residential occupancy exposure”.
Page 8 of Assessing Protectiveness at Sites for VI - 5YR Supplemental Guidance (OSWER Directive 9200.2-84) provides additional direction for the data collection efforts.
The magnitude and extent of the VI investigation is not defined (how VI will be characterized, estimate how many buildings will be assessed).
Additionally, the current monitoring well networks at many sites do not appear adequate to define the extent of groundwater plumes or determine whether plumes remain stable. This affects not only the MNA effectiveness determination but may also hinder the vapor intrusion assessments attributed to VOC plumes.
It is suggested to prioritize the vapor intrusion evaluations at these OUs. Select interim milestones for conducting the vapor assessments by the end of calendar year 2014 and identify 2016 as the date the protectiveness determination can be made
1)Prioritize evaluation of residential indoor air VOC concentrations, followed by office spaces
2) The plume source and boundaries for the OU5 plumes are not well defined, and any VI evaluation at this OU should concentrate on residential housing and office space in and around the OU5 plumes as a priority.
Summary Form OU5 Monitoring Page S-3 Comment: This Five Year Review is intended to evaluate CERCLA-based sites and compounds. The issue for seeps OU5SP-01 and OU5SP-02 is petroleum –based and does not appear to be commingled with CERCLA-based contaminants. The issue and recommendations can be retained in the document as an issue that requires attention due to state regulations, but this should be removed from the Summary Form and the Section 8 and 9 Issues and Recommendations/Follow-up Action Tables, respectively.
Summary Form OU5 Remedy Performance Page S-4 Comment: The slow groundwater attenuation rate issue identified in the Fourth (2014) Five Year Review for the OU5 Remedy Performance is the same as was identified in the Third (2008) Five Year Review. The Recommendation should include finalizing the draft 2010 ST-37 TCE Plume and Source Area Investigation (2011g) and delineate the potential source areas at OU5.
Summary Form Protectiveness Statements Pages S-6 and S-7 OU4, OU5, DP98: Please add a date when the protectiveness determination can be made. (Addendum Due Date).
The Summary form protectiveness statement suggests the evaluation will be conducted in 2016. The Protectiveness Statements in Section 10.0 state the “vapor intrusion assessment is expected to be performed in 2014”.
It is suggested the assessment of vapor intrusion risk will include all residential areas and office space by the end of the calendar year 2014, and a protectiveness determination completed by the end of calendar year 2016. |
Louis Howard |
| 3/17/2014 |
Document, Report, or Work plan Review - other |
EPA Letter to Air Force regarding the 4th Five Year Review for JBER-Elmendorf.
The U. S. Environmental Protection Agency Region 10 has reviewed the Fourth CERCLA Five-Year Review report for Superfund sites, specifically for Operable Units (OU) 1, 2, 4, 5, 6 and DP98 associated with Elmendorf Air Force Base on Joint Base Elmendorf-Richardson, Alaska. The conclusions in this letter are based on the draft report from November 2013 and revised Response to Comments, Summary Form, and Sections 8 and 9 which were received by the EPA on March 12, 2014.
The EPA reviewed the report for technical adequacy, accuracy, and consistency with the National Contingency Plan and EPA guidance. The document provides a summary of the status and protectiveness for OUs for which Records of Decisions (RODs) have been completed and are not determined as No Further Action. It also identifies actions to be taken that ensure protectiveness of the selected remedies and on-going remedial actions and documents a schedule for completion of the recommended actions.
The following are the EPA’s protectiveness determinations for these OUs and the overall Site protectiveness that will be reported to Congress in the EPA’s annual report. Also included are additional recommendations and follow-up actions necessary to address issues raised in the Five-Year Review that affect or could affect protectiveness. In general, the EPA concurs with the protectiveness determinations in this Air Force report. Each OU is discussed individually below.
OU 5
The EPA concurs with the deferred protectiveness determination for OU 5 pending additional sampling to address the potential for vapor intrusion at occupied buildings in proximity to the contaminated chlorinated groundwater plumes. The vapor intrusion evaluation will prioritize buildings with the most vulnerable populations (child care centers, schools, homes or offices occupied by women of childbearing age) and is expected to be completed for all occupied facilities by 2015.
In addition, a benzene contaminated seep at OU5SP-02 remains above cleanup levels, and the source contributing to this contamination is undefined. Natural development of biofilm on the gravel at the seep collection area prevents exposure to ecological receptors. EPA agrees with the recommendation to define the source of contamination of the seeps.
The third Five Year Review (2008) for OU5 recommended further investigation and delineation of the contaminated groundwater plumes. The Air Force acted on the recommendation with the 2011 ST37 TCE Source Area Investigation Report, but has not finalized the report at the time of this review. EPA agrees with the recommendation in the Fourth Five Year Review (2014) to utilize the findings from this groundwater investigation and continue delineation of potential source areas and plumes at OU5. Many of the groundwater plumes at OU5 show decreasing concentrations of contaminants, but will not achieve cleanup levels in the timeframe estimated in the ROD by 2025. Land Use Controls for OU5 prohibit access to contaminated groundwater as a source of drinking water. EPA agrees with the recommendation to evaluate alternative remedies under the process established in the FFA to accelerate attainment of cleanup levels in groundwater at OU5.
An addendum to determine the protectiveness of OU 5 will be prepared by December 31, 2016.
|
Louis Howard |
| 3/20/2014 |
CERCLA ROD Periodic Review |
ADEC appreciates the Air Force’s efforts in completing the Fourth Five Year Review and your project team on addressing ADEC’s comments to finalize the document. ADEC, EPA and JBER project managers have an excellent working relationship and ADEC looks forward to continuing this spirit of cooperation into the future.
ADEC concurs with the deferred protectiveness determination for OU5 pending an assessment in 2015 of the vapor intrusion pathway at manned buildings above and in the vicinity of the contaminant plumes in OU5. Priority for sampling and reporting of results should be given to those buildings with the most vulnerable populations (e,g, child care centers, schools, homes/residences or offices occupied by women of childbearing age). An addendum to the Five-Year Review report should be prepared by December 31, 2016 which incorporates the results of the vapor intrusion assessment and any change on protectiveness for OU5. Benzene at the OU5SP-02 seep remains above cleanup levels, and the source contributing to this contamination is undefined. ADEC agrees with the recommendation to define the source of this contamination.
Several groundwater plumes at OU5 show decreasing concentrations of contaminants, but will not achieve cleanup levels in the timeframe estimated in the ROD for OU5 by 2025. Land Use Controls for OU5 prohibit access to contaminated groundwater as a source of drinking water. ADEC agrees with the recommendation to evaluate further response actions (e.g. alternative remedies) under the process established in the Elmendorf Air Force Base Federal Facility Agreement to accelerate attainment of cleanup levels in groundwater at OU5.
GRO and DRO should be monitored for as part of the early warning and sentry well system since groundwater from upgradient sources (CERCLA and petroleum) in the outwash plain travels to OU5 or be monitored under State regulations as soon as possible since there is no longer a Two-Party Agreement for petroleum and the Air Force agreed that petroleum contamination would be addressed under current State regulations. Petroleum contamination was detected in groundwater at OU5 with levels that exceed current regulatory requirements during the 1994 RI, but GRO and DRO did not have a cleanup level at the time the 1995 ROD was signed and are not currently being monitored.
|
John Halverson |
| 5/14/2014 |
Update or Other Action |
Draft 2013 Annual Field Activities Report received. This report summarizes the 2013 annual long-term management activities, including remedial action-operation (RA-O) and Record of Decision (ROD) requirements, conducted at Joint Base Elmendorf-Richardson (JBER) Comprehensive Environmental Response, Compensation, and Liability Act (CERCLA) sites. The United States Air Force (USAF) has mandated a reduction of long-term environmental liabilities and life-cycle costs through accelerated cleanup of contaminated sites. As such, the Performance-Based Remediation (PBR) initiative has been developed to protect human health and the environment in a cost-effective manner, while at the same time reducing life-cycle costs.
In April 2012, Weston Solutions, Inc. (WESTON) was awarded a PBR contract from the Air Force Civil Engineer Center (AFCEC) (Contract Number FA8903-09-D-8589, Task Order No. 0016). The contract includes performing RA-O and ROD requirements at several JBER sites. The WESTON team performing the activities summarized in this report consists of WESTON and CH2M HILL Constructors, Inc. (CH2M HILL). WESTON executed project work on sites located within JBER-Elmendorf, while CH2M HILL executed project work on sites located within JBER-Richardson.
Fairchild Avenue Plume Site Summary
Based on the historical and 2013 groundwater data, wells located within the plume (wells OU3MW-11, OU5MW-34, and OU5MW-38) continue to exceed OU5 ROD cleanup criteria. Downgradient of the plume, TCE concentrations continue to not be detected in wells OU5MW-43 and OU5MW-46. The TCE trends in the in-plume wells are shown on Figure 12-2. Mann-Kendall trend tests show that there is a statistically significant decreasing trend at the 95% level of significance for wells OU3MW-11, OU5MW-34, and 49WL-01 and an increasing trend for well OU5MW-38.
Kenney Avenue Plume Site Summary
TCE concentrations in the center of the Kenney Avenue Plume (well 403WL-01) continue to exceed the OU5 ROD cleanup criteria. The TCE trend in well 403WL-01 is shown on Figure 12-4. Mann-Kendall trend tests show that there is a statistically significant decreasing trend at the 95% level of significance in the well. Downgradient seeps also continue to have TCE concentrations that exceed the OU5 ROD. The USAF performed the study to evaluate enhanced in-situ bioremediation of chlorinated solvents in groundwater at the Kenney Avenue Plume. These wells were installed and used for injection of an organic substrate and emulsion and monitored during the treatability study. Additional information including results of the study can be found in the study’s final report titled, Treatability Study for Enhanced Bioremediation at the Kenney Avenue Plume, Operable Unit 5 (USAF, 2009d).
Slammer Avenue Plumes Site Summary
The TCE concentrations measured in the western Slammer Avenue Plume at well OU5MW-06 continue to exceed the OU5 ROD cleanup criteria; however, it exhibits a decreasing trend. The TCE trend in well OU5MW-06 is shown on Figure 12-6. Mann-Kendall trend tests show that there is a statistically significant decreasing trend at the 95% level of significance in the well. The TCE concentrations measured in the eastern Slammer Avenue Plume at well OU5MW-07 continue to exceed the OU5 ROD cleanup criteria; concentrations measured at this well have been similar from 2007 through 2013. The eastern Slammer Avenue Plume cross-gradient well (OU5MW-08) and well located at the leading edge of the plume (GW-4A) do not have concentrations exceeding the OU5 ROD cleanup criteria. This plume has been identified as the leading edge of the SS022 Plume. It is recommended that the wells monitoring the former eastern Slammer Avenue Plume be discontinued from monitoring for ST037 once a monitoring program for SS022 has been established to avoid duplication.
OU5MW-02 Plume Site Summary
The TCE concentrations in wells OU3MW-02 and OU5MW-44, located inside the plume, remain above the OU5 ROD cleanup level of 5 µg/L. The TCE trends in these two wells are shown on Figure 12-8. Mann-Kendall trend tests show that there is a statistically significant decreasing trend at the 95% level of significance for well OU3MW-02. The Mann-Kendall trend test showed no significant trend for well OU5MW-44. TCE has not been detected in the downgradient early warning well OU5MW-45, demonstrating that the OU5MW-02 Plume is stable and not migrating off the installation.
SP1-02 Plume Site Summary
The TCE concentration at well SP1-02 has shown a decreasing trend but remains just above the
cleanup level of 5 µg/L. The TCE trend in well SP1-02 is shown on Figure 12-10. Mann-Kendall trend tests show that there is a statistically significant decreasing trend at the 95% level of significance in the well. Downgradient well OU5MW-15 results indicate that the plume is not migrating. Well OU5MW-45 and seep OU5SP-15 results still bound the plume to the northwest
and east. |
Louis Howard |
| 5/14/2014 |
Update or Other Action |
Draft 2013 Annual Field Activities Report received. This report summarizes the 2013 annual long-term management activities, including remedial action-operation (RA-O) and Record of Decision (ROD) requirements, conducted at Joint Base Elmendorf-Richardson (JBER) Comprehensive Environmental Response, Compensation, and Liability Act (CERCLA) sites. The United States Air Force (USAF) has mandated a reduction of long-term environmental liabilities and life-cycle costs through accelerated cleanup of contaminated sites. As such, the Performance-Based Remediation (PBR) initiative has been developed to protect human health and the environment in a cost-effective manner, while at the same time reducing life-cycle costs.
In April 2012, Weston Solutions, Inc. (WESTON) was awarded a PBR contract from the Air Force Civil Engineer Center (AFCEC) (Contract Number FA8903-09-D-8589, Task Order No. 0016). The contract includes performing RA-O and ROD requirements at several JBER sites. The WESTON team performing the activities summarized in this report consists of WESTON and CH2M HILL Constructors, Inc. (CH2M HILL). WESTON executed project work on sites located within JBER-Elmendorf, while CH2M HILL executed project work on sites located within JBER-Richardson.
Seeps, Surface Water, and Wetland Remediation Systems Site Summary
The results of visual inspection and assessment of analytical data collected over 28 months
demonstrate that pumping is not required for the Wetland Remediation System to reduce influent
COC concentrations in seeps to concentrations that are below applicable cleanup levels.
Continued operation of the Wetland Remediation System in a passive configuration is recommended.
As stated previously, Pump Station #3 was shut down in 2007 because the results of Phases I and
II of the Wetland Remediation System Optimization Study indicated that COC degradation within the two seep collection areas serviced by Pump Stations #1 and #2 was sufficient to achieve applicable cleanup standards within the seep collection areas prior to discharge from those areas.
Early Warning and Sentry Wells Site Summary
Analytical samples collected from Early Warning and Sentry wells in 2013 were all below the
OU5 ROD cleanup criterion for TCE. No changes are being proposed for the Early Warning and
Sentry well sampling program. |
Louis Howard |
| 5/22/2014 |
Document, Report, or Work plan Review - other |
Staff provided comments on the Draft 2014 Remedial Action-Operation & Maintenance WP Addendum JBER, Alaska dated May 2014.
Table 1
ST037 Early Warning Wells and Sentry Wells
ADEC is requesting that the early warning wells be sampled for diesel range organics and gasoline range organics in addition to VOCs. Other constituents that are to be considered for monitoring at these wells are 1,4-Dioxane, PFOS and PFOA (PFCs). ADEC has raised the issue with the Air Force numerous times formonitoring of 1-4 Dioxane and PFCs. The issue remains unresolved at this time.
The purpose of the early warning and sentry wells are not just for OU 5 ROD COCs, but from upgradient contaminant plumes not found in OU 5 and source areas not listed in the OU 5 ROD including identified and unidentified petroleum source areas.
1994 RI/FS E.2 Feasibility Study Page 18 COCs for OU5: “Remedial actions considered for groundwater and surface seeps in OU 5 must also accommodate contaminants that may migrate in groundwater from all upgradient sources.
Therefore, the list of COCs may be expanded in the future, if new COCs are identified during groundwater characterization investigations in areas upgradient from OU 5.”
March 26, 1993 Basewide Groundwater memorandum of agreement between USAF, USEPA and ADEC indicated that any groundwater contamination from upgradient of OU5 would be dealt by OU5 regardless of CERCLA or POL source areas and not be limited to COCs identified specifically in OU5 Record of Decision.
“As a result of the basewide groundwater study and the FY92 field work that occurred at Operable Units (OUs) 1, 2, and 5 it appears that a large portion of the groundwater flows into OU5 (Atch 1). Based on this information Elmendorf AFB would like to move all upgradient groundwater into the OU5 Feasibility Study, Proposed Plan and Record of Decison. This means we would address all groundwater from upgradient sources (CERCLA (ST20, OU3, & OU4) and SERA) at OU5 instead of at each individual source area (Atch 2).”
Use of Passive Diffusion bags (PDBs) are acceptable for LTM and many VOCs, but not for closure monitoring and not for GRO, DRO, metals, and PAHs. Use of PDBs shall not be accepted for the required 2 year closure groundwater monitoring. Use of PDB data from any groundwater well shall not be used for comparison to Table C with respect to discontinuing GW monitoring.
1994 RI/FS Page 645 7.8 Contaminants of Concern states: “Remedial actions considered for groundwater and surface seeps in OU 5 must also accommodate contaminants that may migrate in groundwater from all upgradient sources. Therefore, the list of COCs may be expanded in the future, if new COCs are identified during groundwater characterization investigations in areas upgradient from OU 5.”
1994 RI/FS Table 8-1 Specific Remedial Action Objectives for OU5 Eighth Bullet: “Design the remedial action for groundwater to address contaminants from groundwater at Elmendorf AFB upgradient from OU 5. Build enough flexibility into the alternatives to allow for addressing new contaminants and varying concentrations of contaminants.”
|
Louis Howard |
| 6/4/2014 |
Document, Report, or Work plan Review - other |
Staff provided comments on the Annual CERCLA GW report.
ST037
Fairchild Avenue Plume
See comment regarding 1,4-dioxane analysis in GW & ICs adequacy being “N/A” & dig permits during the last 12 months.
The results from the ST37 TCE Plume & Source Area Investigation Report (Draft Final October 2011) needs to be acknowledged & incorporated into the annual report. 2011 Zones 1, 2, & 3 Annual Report stated: “Additional discrete GW samples were collected during the 2010 field season as part of a study performed to evaluate the current horizontal & vertical extents of individual plumes within Site ST37. The results of this study will be reported under separate cover.”
However, the 2012 & 2013 reports do not mention what was the result of the 2011 ST37 TCE plume investigation & how it relates to what was detected during the annual GW monitoring effort.
Pages 12-2 & 12-3
For TCE, wouldn’t one expect the shallower wells not to have as much contamination as the “deep wells based on the propensity of chlorinated solvents to move downward in an aquifer? Perhaps if the Air Force were to install deeper monitoring wells with screens below = the water table & downgradient, one might see more TCE in the sampling results?” This topic needs to be discussed at the next RPM meeting & dealt with instead of just reporting it year after year & not doing anything about it.
Site Inspection Checklist: If excavation activity is being conducted for “possibly electrical lines” shouldn’t the comment include a recommendation to check for dig permit that allows for excavation activities by Pump Station #1 or even an actual review of dig permits issued for this area conducted as part of the scope for this project?” Photos of the excavation would have been helpful & a good reference as part of this document.
Page 12-9
12.4 Kenney Avenue Plume
The text states: “The source of contamination for this plume is attributed to historical activities at Building 5332, the Former Diesel Maintenance Shop Yard (USAF, 1994b).”
However, the text from a later document - ST37 TCE Plume & Source Area Investigation Report Draft Final (October 2011) states in Section 1.2.3.2: “Data from annual GW monitoring at wells near Building 5332 was used to determine that the source of contamination for the Kenney Avenue Plume is not Building 5332 (USAF, 2008).”
Please clarify which statement is true & correct text & include the 2011 draft final report as a reference.
Delete text “The Kenney Avenue Plume is also believed to contribute to TCE concentrations detected in GW seeps along the bluff near the location of the engineered Wetland Treatment Cell.”
Instead state: “TCE has been detected in a downgradient direction at several seep locations at the base of a bluff below 2nd Street, indicating that the [Kenney Avenue] plume is discharging to the surface at the northern fringe of the Ship Creek flood plain.” (ST37 TCE Plume & Source Investigation Section 1.2.3.2 Page 1-9). There are no other probable sources of TCE for the seeps besides the Kenney Avenue Plume.
The text states that well OU5MW-45 is an Early Warning Well & was sampled two times for VOCs using a passive diffusion bag sampler. TCE was not detected at concentrations above the sample method limit of detection in well OU5MW-45 during the either sampling event.
As an Early Warning Well, one would not expect to see TCE or any other contaminant above applicable cleanup levels, since that would mean potential off-site migration of contaminants towards sensitive receptors or environment (e.g. Ship Creek).
Please clarify whether or not the PDBS was deployed at the top of the screened interval or the bottom of the screened interval in OU5MW-45 & how long the PDBS was deployed until sampled for each sampling event. If deployed each time at the top of the screened interval, it may not be optimally placed to monitor TCE in GW which tends to “sink”. The screened interval for OU5MW-45 in the shallow aquifer is from 95.58 – 110.58 feet amsl, which is approximately 15’ (Table 1.2 2010 Zone 3 Management Area Annual Report). Also provide some general observation of the PDBS overall condition (e.g. indication of biofouling, staining, etc).
The 2011 Zones 1,2,3 Annual Report states: “Additional discrete GW samples were collected during the 2010 field season as part of a study performed to evaluate the current horizontal & vertical extent of individual plumes within Site ST37. The results of this study will be reported under separate cover.”
The 2012 & 2013 do not mention if the ST37 investigation (draft final October 2011) results for evaluation of the horizontal & vertical extent of plumes was successful or not & what impact the findings has on subsequent GW monitoring at OU5MW-02. |
Louis Howard |
| 11/5/2014 |
Document, Report, or Work plan Review - other |
EPA provided comments on the draft CERCLA report.
Comment: This entire discussion on ST-37 should be updated to include new conclusions and recommendations in the ST37 TCE Plume and Source Area Investigation Report, draft final, October 2011.
Comment: Please correct the statement on COCs to be accurate. Benzene still exists above cleanup levels in seep OU5-SP02.
Comment: The sources and CSM for ST037 needs to be updated using the October 2011 TCE Plume and Source Area Investigation Report. A portion of site SD16 located NE of Bldg 8237 is likely source of contamination for the western lobe ST037 Plume (formerly Fairchild Plume).
Comment: There are a number of comments and concerns on Figure 12-1:
• Explain in the narrative and on Figure 12-1 that 'deep' wells are still in the shallow aquifer, just screened 15-30 ft below the water table.
• The October 2011 TCE Plume and Source Area Investigation Report determined the likely source of TCE is in the area of bldg 8237.
• 2011 TCE source investigation recommends continue monitoring at 49WL01. Why was it discontinued in 2007?
Comment: Update source location based on 2011 ST037 TCE Investigation to be near Bldg 4314.
Comment: Why isn't there quarterly data for OUSP-09 in 2013? The narrative suggests OU5SP-09 was sampled quarterly; only OUSP-10 was frozen during the last quarter sampling.
Comment: Update with ST037 TCE investigation; upgradient area of plumes undefined (near 19th and 20th street near Bldg 8515 - is this SS022?).
Comment: Please clarify why there is no 2013 discussion or data for the point of compliance with surface water (BPSW-01)?
Comment: Agree in theory with this recommendation but a more detailed analysis of the 2011 TCE report and SS22 groundwater plume boundaries should be conducted (perhaps using MAROS) prior to discontinuing monitoring of wells associated with ST037 Slammer Plumes.
Comment: Update with info from the ST037 TCE investigation. This is part of a central lobe of the ST37 plume; swale/trench near SD016 possible source.
Comment: Please clarify why the MNA evaluation stops with 2010 data. Does this mean the biogeo data from 2011, 2012 and 2013 have not been evaluated in relation to data 2010 and earlier?
Comment: Update with ST037 TCE report; source is likely at OU5MW-44.
Comment: The Slammer Avenue plume depicted on this figure is labeled as the SS022 plume on Fig 12-5. Please correct this inconsistency.
Comment Please finish or clarify the incomplete sentence “Additionally, in order to identify if contaminant concentrations increase to levels that would potentially impact environmental receptors, such as Ship Creek.”
Comment: Add in the ST037 TCE investigation report; Jacobs had a copy of it in 2013 as it was used in discussions in the JBER-E FYR. |
Louis Howard |
| 6/29/2015 |
Document, Report, or Work plan Review - other |
Staff reviewed and commented on the Well Decommissioning work plan covering several sites.
Main comments were regarding the use of an alternate well in lieu of well OU5MW-01 to monitor for any chlorinated solvents and future monitoring for 1,4-dioxane from the Fairchild Plume. Finally, staff stated that given 1,4-dioxane’s propensity to travel in groundwater well beyond the detected concentrations of its source material (i.e. TCE), well OU5MW-43 may not be in position to capture the furthest extent of 1,4-dioxane contamination. |
Louis Howard |
| 7/23/2015 |
Update or Other Action |
Draft Annual Field Activities report received for review and comment.
For the eastern lobe of the Western ST037 Plume (formerly the Kenney Avenue Plume), a new monitoring well is needed to evaluate trends in a previously unknown source area. An optimized method to selecting the location and screen interval for this source area monitoring well is to collect discrete groundwater samples between discrete sample locations FA01-2010, KA03, and KA05.
For the central lobe of the Western ST037 Plume, one or more new monitoring wells are recommended for installation north of Fighter Drive to monitor source area(s). An optimized method to selecting the location and screen interval for each new well is to collect discrete groundwater samples between existing monitoring wells and the discrete groundwater sample points installed in 2010 as part of this study to determine the number and optimal monitoring location for each source are.
For the western lobe of the Western ST037 Plume, (formerly the Fairchild Avenue Plume), installation of one source area well near Building 6211 between Arctic Warrior Drive and 12th Street is recommended. An optimized method to selecting the location and screen interval for this source area monitoring well is to collect discrete groundwater samples to supplement discrete sample locations installed in 2010 to determine the location of the highest TCE concentration in this area
A discrete sampling event, outside of the LTM program , based on the 2010 investigation results and recommendations, which includes the installation of a minimum of three new wells and discrete sampling of up to 12 existing wells, is recommended to further delineate the Western ST037 Plume and optimize the current sampling approach. This sampling event would be used to determine the efficacy of current well network and add or remove wells based on results.
The TCE concentrations measured in the eastern Slammer Avenue Plume at wells OU5MW-06 and OU5MW-07 continue to exceed the OU5 ROD cleanup levels; concentrations measured at this well have been similar from 2007 through 2014. The eastern Slammer Avenue Plume crossgradient well (OU5MW-08) and well located at the leading edge of the plume (GW-4A) do not have concentrations exceeding the OU5 ROD cleanup levels. This plume has been identified as the leading edge of the SS022 Plume. It is recommended that a monitoring program for SS022 be established and the wells monitoring the former eastern Slammer Avenue Plume be discontinued to avoid duplication of effort.
NOTE to file: Future five-year reviews for OUs 1, 2, 4, 5 and 6 and DP098 are necessary because contamination remains above levels that allow for UU/UE in these areas. The next five-year review is due on or before March 17, 2019.
See site file for additional information. |
Louis Howard |
| 8/10/2015 |
Document, Report, or Work plan Review - other |
Staff provided comments on the Annual CERCLA Report. Staff commented on the need to sample groundwater for 1,4-dioxane associated with TCE contamination. Also, staff provided comments on sampling requirements for sampling for Perfluorinated compounds at seep/surface water sites and early warning/sentry well locations. |
Louis Howard |
| 4/11/2016 |
Document, Report, or Work plan Review - other |
Staff provided comments on the draft PFC Site Inspections work plan for JBER-E and JBER-R.
Main comments were regarding obtaining prior approval from ADEC and EPA project managers before making changes to the approved QAPP and that the EPA RSSLs are less stringent than the human health soil cleanup levels and migration to ground cleanup levels ADEC will be promulgating this winter (2016). It was noted that WS# 10 is especially vague: "Based on the above, the best available screening criteria for PFOA and PFOS releases are the EPA PHAs for groundwater and RSSLs for soil. Because ADEC has proposed lower concentration limits that are in the public
comment process, the ADEC levels should also be considered."
It states that ADEC levels should also be considered, however in WS # 11, it states the concentrations of PFOA and PFOS in soil and groundwater will be compared to project screening levels based on the most conservative risk based EPA or ADEC values.
For determining presence or absence of PFOS and PFOA using solely risk based screening levels is not acceptable to ADEC. If the migration to groundwater cleanup level is adopted by ADEC and it exceeds for PFOS or PFOA, a release is confirmed and it is deemed to be contaminated by ADEC. 18 AAC 75.990 Definitions.
(23} "contaminated soil" means soil containing a concentration of a hazardous substance that exceeds the applicable cleanup level determined under the site cleanup rules. If AFCEC chooses to proceed with risk based values (as it is apparent upon review of Table 10-2 Steps 2, 4, & 5), then ADEC reserves the right to require further investigation/cleanup under 18 AAC 75 for all areas of concern/source areas where AFC EC determined no addition action was necessary at an area of concern/ source area, but the PFC levels detected exceed migration to groundwater cleanup levels for PFCs.
See site file for additional information. |
Louis Howard |
| 5/4/2016 |
Document, Report, or Work plan Review - other |
Staff provided comments on the draft VI WP.
To be consistent with text on Page 41 of the document, restate as follows (it is redundant but an important issue worth repeating and emphasizing:
“HGL will immediately notify JBER, ADEC and AFCEC if any indoor air, soil gas, or sub-slab gas sampling result identifies one or both of the following: a chemical concentration greater than the respective ADEC Indoor Air Target Level (ADEC, 2012); soil gas or sub-slab chemical concentrations greater than 10,000 times ADEC Target Levels or an unacceptable risk to human health. HGL will make this notification based on either preliminary or final data regardless of the status of VI Study Report and VI Risk Assessment development to allow for an immediate assessment of building occupant safety. Indoor air sampling results will be reviewed after each field data collection event.”
ADEC requests clarification in the text on whether the inability to collect PID readings in some buildings inhibit their inclusion as a BOI? PID screening results in buildings were utilized to create the BOI list; thus the inability to field screen in a building may reduce the chance these buildings would be included in the BOI list. If PID readings were not measured in a building then the building should be assumed to have a positive PID headspace readings as a conservative measure.
TCE may be the only CERCLA ROD chemical of concern but there are other volatile contaminants present that may present a vapor intrusion issue. ST037 monitoring results in the 2014 Annual Field Activities Report – 2014_CERCLA sites_Crosstab.xls: 14ST037-Q4-OU5SP02-SP-0 lab ID 1146094004 12/16/2014 11:58 had a detected benzene result in groundwater at 18.8 µg/L.
ADEC recommends that the composite indoor air samples not be limited to 24 hour intervals. Site conditions may be present such that indoor air composite samples greater than 24 hours (e.g. two weeks) be collected particularly if there is a weather event in which the barometric pressure changed significantly. Additionally, if the during the first event there is significant variation between indoor sample results within a building, collection of samples over a longer time frame may reduce some of the sample results variability.
Please expand the discussion on the approach to sample location selection. Rooms or areas in buildings with greater occupancy or traffic should be considered when choosing locations of sub-slab and indoor air samples. Furthermore, building rooms or areas with sensitive receptor occupancy should also be considered. If an HVAC system is intermittently operating, then recommend that samples be collected during times it is not operating.
Additionally, please provide a rationale for selection of the outdoor air sample location. Outdoor air samples are often collected on the roof of buildings upgradient of prevailing wind direction
The text states: “TCE is the only COI at this site. Each building is discussed below.”
Building 7535
The RI/FS for SS022 4.4.9 stated: “Two subslab samples were collected, one from beneath the slab in each of these two areas where the boilers were located. Sample SG01 had an exceedance for 1,2,4-trimethylbenzene, while SG02 had no detected exceedances. Both of the samples from this building had elevated detection limits as a result of leak detection gas (1,1-difluoroethane) in the sample. While the amount of leak detection gas in the sample is well within the acceptable range according to ADEC guidance, it did cause the detection limits to increase. While the data is useable, the uncertainty associated with the elevated detection limits will be addressed in the draft risk assessment.”
See site file for additional information. |
Louis Howard |
| 1/13/2017 |
Update or Other Action |
ADEC received a GW monitoring report for several JBER sites which summarizes the 2015 annual long-term management (LTM) activities, including remedial action-operation (RA-O) & ROD requirements conducted at JBER CERCLA sites.
The TCE levels in the eastern Slammer Ave. Plume at OU5MW-06 & OU5MW-07 continue to exceed the OU5 ROD cleanup goal which have been similar from 2007 through 2015. The plume’s cross-gradient well (OU5MW-08) does not have TCE above the OU5 ROD cleanup goal, but GW-4A located at the leading edge of the plume does exceed it for the first time. This plume has been identified as the leading edge of the SS022 Plume & contamination from Site TU091 may be the source of the western Slammer Avenue Plume.
Well GW-4A is downgradient of the drainage ditch and the 2015 results exceed the TCE cleanup level. To help determine the extent of the TCE plume, the collection of samples for TCE & PCE analyses from the next downgradient well screened over the same approximate depth is recommended. Well SS37MW07 would be the most representative as it completed to 16.0’ below top of casing GW-4A was completed to 12.3’. It is also recommended to continue quarterly surface water monitoring at the existing Beaver Pond Area surface water monitoring points to demonstrate compliance with ADEC’s water quality standards.
It is recommended to keep the quarterly surface water sampling at the wetland treatment cell because the Mann-Kendall trend results show an unstable plume. The daylighting GW near pump station #3 is not associated with the inactive treatment system nor is it associated with seeps or surface water from the bluff. Water levels in the wet wells & force main are several feet bgs in this area & cannot contribute to the GW discharge area by the railroad.
Recommendations for the eastern lobe of the Western ST037 Plume (fka the Kenney Ave. Plume), a new well is needed to evaluate trends in a previously unknown source area. The location & screen interval for this new source area well may be selected by the collection of additional discrete GW samples between previous discrete sample locations FA01-2010, KA03, & KA05. For the central lobe of the Western ST037 Plume, the installation of a new well is recommended north of Fighter Drive to monitor source area(s). The location & screen interval for the new well may be selected by the collection of additional discrete GW samples between existing wells & the discrete GW sample points installed in 2010. In addition, it is recommended that the damaged well OU5MW-34 be inspected for possible repairs. If it cannot be repaired, it should be decommissioned & replaced.
Sample frequency to remain quarterly at the Beaver Ponds for all surface water locations. Inspect & repair or replace monitoring well OU5MW-34.Inclusion of well OU5MW-46 (previously sampled using low flow sample methods) into the Early Warning & Sentry Monitoring Well (EWSMW) network, replacing OU5MW-01 (sampled using PDB methods). Inclusion of OU5MW-46 into the EWSMW network would change the sampling method from a low flow method to a PDB sampling method.
See site file for additional information. |
Louis Howard |
| 4/26/2017 |
Update or Other Action |
Draft Seep Assessment work plan received for review and comment. The project objectives are to address the recommendation made in the 2014 CERCLA Five-Year Review for JBER-E, and to (1) identify the source and delineate the extent of soil and groundwater contamination that is resulting in elevated concentrations of benzene, TAH, and TAqH in seeps 1 and 2 and (2) predict the timeframe to meet RAOs (via natural attenuation) at the seeps.
Concentrations of benzene, TAH, and TAqH in groundwater have been detected above the
cleanup levels at seeps 1 and 2 since 2003. Based on the large historical release of fuel identified in the OU5 RI, the potential exists for significant residual fuel contamination to remain in the soil that may act as a source of groundwater contamination.
Data gaps identified for ST037 include the following:
? The location of the source area(s) is unknown and the extent of soil contamination
contributing to benzene, TAH, and TAqH at concentrations above cleanup levels at seeps 1
and 2 has not been delineated. The origin and source of the on-going contamination at seeps
1 and 2 is thought to be the subsurface diesel fuel line leak in the late 1950s from the
pipelines situated at the top of the bluff; however, the exact location of the leak was never
identified. In addition, two USTs removed in September 1993 in the vicinity of Building
2218 and soil contamination encountered in 2013 during the installation of a tower and
antenna system south of Building 2228 have been identified as potential sources.
? The nature and extent of upgradient groundwater contamination contributing to elevated
concentrations of benzene, TAH, and TAqH at seeps 1 and 2 has not been delineated.
? Geotechnical data for use in predicting the timeframe to achieve the RAOs at seeps 1 and 2
via natural attenuation is needed.
See site file for additional information. |
Louis Howard |
| 5/11/2017 |
Update or Other Action |
Staff noted that TAqH: summation of the following PAHs: Acenaphthene, acenaphthylene, anthracene, benzo(a)anthracene, benzo(a)pyrene benzo(b)fluoranthene, benzo(g,h,i)perylene, benzo(k)fluoranthene, chrysene, dibenzo(a,h)anthracene, fluoranthene, fluorene, indeno(1,2,3,-cd)pyrene, naphthalene, phenanthrene, pyrene plus TAH.
Please state as part of the 1994 RI, an independent gaseous standard was not analyzed to calibrate the soil gas samples. Therefore, the soil gas sample concentrations could be quantitated because the standard headspace concentration was unknown and the soil gas results were designated as “unitless.” The soil gas screening results from the 1994 RI are qualitative and indicated the absence or presence of constituents.
See site file for additional information. |
Louis Howard |
| 6/1/2017 |
Update or Other Action |
Draft site inspection (SI) at aqueous film forming foam (AFFF) areas on JBER-E and JBER-R waa received for review and comment. The purpose of the SI was to determine the presence or absence of perfluorooctanoic acid (PFOA) and perfluorooctane sulfonate (PFOS) in the environment. These compounds are a class of synthetic fluorinated chemicals used in industrial and consumer products, including defense-related applications. This class of compounds is also referred to as per- and polyfluorinated alkyl substances (PFAS).
Groundwater Results- Four groundwater samples were collected from surface seeps OU5SP-01, OU5SP-02, OU5CP002, and OU5SP-011. PFBS was detected at concentrations below the EPA RSL. PFOA was detected at concentrations above the EPA HA but below the ADEC cleanup level at OU5SP-01, OU5SP-02, and OU5CP-02, and at a concentration above the EPA HA and the ADEC cleanup level at OU5SP-11. PFOS was detected at a concentration below the EPA HA and ADEC cleanup levels at OU5SP-01, above the EPA HA but below the ADEC cleanup level at OU5SP-02 and OU5CP-02, and above the EPA HA and ADEC cleanup level at OU5SP-11.
Surface water results- One surface water sample was collected from surface water locationWCSW-02 at ST037. PFBS was detected at a concentration below the EPA RSL. PFOA and PFOS were detected at concentrations above the EPA HA and the ADEC groundwater cleanup level.
See site file for additional information. |
Louis Howard |
| 6/13/2017 |
Document, Report, or Work plan Review - other |
Staff reviewed the Draft SI Report for AFFF Areas on JBER-E and JBER-R sites. Data indicate that ST037 and LF004 seeps, located at the southern and southwestern Base boundaries, have been impacted by PFAS in groundwater and may be migrating off base in groundwater and surface water.
It appears there are documented releases of PFOS and/or PFOA at these areas which require additional investigation through a remedial investigation/feasibility study under CERCLA or as required by 18 AAC 75.335 Site Characterization.
See site file for additional information. |
Louis Howard |
| 7/17/2017 |
Document, Report, or Work plan Review - other |
EPA received the Draft Site Inspection Report for Aqueous Film Forming Foam Areas, Joint Base Elmendorf-Richardson, Alaska, May 2017 for review the week of June 2, however Appendix B2 (App B2) laboratory data was not included. EPA received App B2 for review the week of June 20. EPA preliminary comments were sent to the Air Force on July 17, 2017. EPA Office of Research & Development staff, as well as EPA Region 5 Laboratory chemists, reviewed App B2. EPA has asked the Air Force for clarification regarding what level of report & data review was done by the government prior to submittal of the report to EPA & have not received a clear response.
EPA’s initial review has identified a number of data quality issues & that the government data review should be completed & submitted to EPA before we are asked to finalize our comments. The comments submitted reflect only those requiring clarification on the narrative or figures & do not concern data quality or final conclusions on the source areas based on the data. The comments are not inclusive of review of the laboratory data & therefore cannot substantiate any conclusions drawn on the presence or absence of PFAS at the twenty-six areas of concern.
The subsections of Section 2.3 do not clearly identify the potential sources of per- and polyfluorinated alkyl substances (PFAS) associated with the two seep sites, LF004 and ST037 (e.g., disposal of AFFF, migration in groundwater from other AFFF areas, etc.). Please revise Section 2.3 to clearly identify the potential sources of PFAS associated with the two seep sites, LF004 and ST037.
Section 3.7.27.3 references seep location “OU5CP002” and seep location “OU5CP-02,” but it appears these both refer to the same location. The location numbers should be consistently presented. Please revise Section 3.7.27.3 to consistently present the seep location numbers.
See site file for additional information.
|
Louis Howard |
| 8/28/2017 |
Exposure Tracking Model Ranking |
Initial ranking with ETM completed for source area id: 71610 name: Underground tank |
Louis Howard |
| 11/7/2017 |
Update or Other Action |
Letter report received for CY2016 [January 1, 2016 - December 31, 2016] Annual Land Use Control (LUC) and Institutional Control (IC) Monitoring at Joint Base Elmendorf-Richardson (JBER). This letter serves as the annual monitoring report on the status of LUCs/ICs in place on JBER-Elmendorf (JBER-E) and JBER-Richardson (JBER-R). The Air Force ensures compliance with LUCs by conducting periodic monitoring and site inspections. Formal LUC/IC inspections occur annually on JBER during late spring through early fall and are typically conducted by contract. A total of 55 sites were formally inspected. Random site inspections are also conducted throughout the year by JBER Restoration staff.
Discrepancies: A few areas of construction activities that included ground disturbances were noted: 1) disturbance around an electrical box near the intersection of Jerstad Ave and Arctic Warrior, 2) construction activities related to utility installation at the intersection Sijan Ave. and Arctic Warrior, and 3) a section of asphalt was cut near well 61WL-04 along Sijan Ave. None of the disturbances were in areas of known or suspected contamination. Repairs were made at well OUSMW-34 and the inner PVC casing was repaired to enable the well to be sampled. Well
OUSMW-15 was cut down during maintenance activities.
See site file for additional information. |
Louis Howard |
| 11/21/2017 |
Update or Other Action |
Per AFCEC email: A memo from the USACE summarizing issues found in their review should be in hand on the 4th of December. |
Louis Howard |
| 11/30/2017 |
Update or Other Action |
Draft VI report received for review & comment. Building 7265 is an operational commercial/industrial use facility that includes offices, storage areas, & a garage on the ground floor, & is occupied by approximately 6 people on a normal workweek day shift basis (Monday - Friday, 9 hours per day). Floor penetrations include floor drains, an in-floor vault/sump, & concrete floor seams (all in the garage). Building 7265 is located entirely within the ST037 GW contamination plume boundary & TCE is the only COI. The depth to GW is approximately 15 feet bgs.
TCE was detected in indoor air during FSE1 & FSE2, & in soil gas during FSE1. There is no spatial bias apparent in the locations of the TCE detections in ambient air or soil gas. The detections of TCE in soil gas & indoor air suggest the presence of a complete VI pathway. Based on the above lines of evidence, the VI pathway is considered complete at Building 7265.
Building 4228 is located entirely within the boundary of a VOC GW contamination plume with the depth to GW approximately 29 feet bgs. The building is airtight during normal operations & includes a vapor barrier beneath the concrete slab floor. Floor penetrations are limited to floor drains in the restrooms. No non-VI ambient air TCE contaminant sources were identified. Sub-slab air pressure gradients do not apply to Building 4228, as all soil gas samples were collected from near-slab locations to avoid potential damage to the vapor barrier.
Although TCE was detected in indoor air during FSE2, the low estimated concentrations are near the lab reporting limit & are lower than the ND reporting limit values from FSE1. Combined with the detection of TCE in only one soil gas sample at a low estimated concentration, the sample results do not suggest the presence of a complete VI pathway. Based on the above lines of evidence, the VI pathway is considered incomplete at Building 4228.
Regarding short-term exposure to TCE in indoor air, the maximum detected indoor air concentrations of 8.7 µg/m3 (FSE1) & 7.1 µg/m3 (FSE2) are slightly > one or both of USEPA’s TCE industrial Indoor Air Response Action Levels of 7 µg/m3 (10-hour work day) & 8 µg/m3 (8-hour work day).
Sub-slab air pressure gradients do not apply to Building 4230, as all soil gas samples were collected from near-slab locations. Although TCE was detected in indoor air during both sampling events & in soil gas during FSE1, the crawlspace air concentrations do not support the observed indoor air concentrations relative to a complete VI pathway from soil gas. The indoor air results suggest the presence of a non-VI source for TCE within the trailers. Based on the above lines of evidence, the VI pathway is considered potentially complete at Building 4230.
Building 5208A is located within the buffer zone; the western half of Building 5211A is located within the boundary of a VOC GW contamination plume with the depth to GW approximately 27 feet bgs. The buildings are generally airtight & include a vapor barrier beneath the concrete slab floor. No floor penetrations or drains were observed. Sub-slab air pressure gradients do not apply to Buildings 5208A, as all soil gas samples were collected from near-slab locations to avoid potential damage to the vapor barrier.
Soil gas sampling was not conducted at Building 5211A (only ambient air samples during FSE2). Although TCE was detected in one of two soil gas samples, no TCE was detected in either building during the respective sampling events. Therefore, the VI pathway is considered incomplete at Buildings 5208A/5211A
TCE was detected in soil gas during FSE1 & in indoor air during both sampling events. TCE in indoor air were consistently > outdoor air. TCE soil gas detections were oriented along a southwest-to-northeast line, with concentrations decreasing from the southwest to the northeast. The TCE detections in soil gas & indoor air suggest the presence of a complete VI pathway. Based on the above lines of evidence, the VI pathway is considered complete at Building 8515.
See site file for additional information. |
Louis Howard |
| 1/23/2018 |
Document, Report, or Work plan Review - other |
Draft Vapor Intrusion study received for review and comment.
Main comment was to add text stating the main purpose of sampling was to help address the Operable Unit 5 protectiveness deferred statements in the Fourth CERCLA Five-Year Review. Other comments are to add information regarding the 500 gallon used oil tank associated with a former oil/water separator (OWS) located at building 8574 in the text and figure for ST037.
See site file for additional information. |
Louis Howard |
| 1/23/2018 |
Document, Report, or Work plan Review - other |
Draft Vapor Intrusion study received for review and comment.
Main comment was to add text stating the main purpose of sampling was to help address the Operable Unit 5 protectiveness deferred statements in the Fourth CERCLA Five-Year Review. Other comments are to add information regarding the 500 gallon used oil tank associated with a former oil/water separator (OWS) located at building 8574 in the text and figure for ST037.
See site file for additional information. |
Louis Howard |
| 2/8/2018 |
CERCLA SI |
SI responses to ADEC's comments are satisfactory and may be incorporated into the final report. with the exception of lack of clarity in the response on which program the PFAS contamination will be investigated under at JBER: RI/FS in accordance with CERCLA as new source areas under the Federal Facility Agreements OR as new sites under State Authority (i.e. 18 AAC 75).
ADEC is requesting specific responses as to which path the investigation will occur (RI/FS per the FFA or Site Characterization per 18 AAC 75..335). Please respond. Additionally, ADEC is reviewing the Data Quality Evaluation Report AND the Technical Memorandum for Data Quality Findings Perfluorinated Compound Site Inspection for Joint Base Elmendorf-Richardson |
Louis Howard |
| 2/9/2018 |
Document, Report, or Work plan Review - other |
Staff reviewed and commented on the draft Annual report for CERCLA sites. Main comments were on requiring PFOS and PFOA sampling for all groundwater samples from this source area. Monitoring well OU3MW-02 had PFOA and PFOS detected at concentrations above the EPA HA and the ADEC cleanup levels.
Western ST037 Plume, Slammer Avenue Plumes: ADEC will require all surface water/seep areas be tested for PFOS and PFOA. PFOA was detected at concentrations above the EPA HA but below the ADEC cleanup level at OU5SP-01, OU5SP-02, and OU5CP-02, and at a concentration above the EPA HA and the ADEC cleanup level at OU5SP-11. PFOS was detected at a concentration below the EPA HA and ADEC cleanup levels at OU5SP-01, above the EPA HA but below the ADEC cleanup level at OU5SP-02 and OU5CP-02, and above the EPA HA and ADEC cleanup level at OU5SP-11.
Seeps, surface water and wetland remediation system: Staff will require from this point forward, PFOS/PFOA sampling be conducted in all seeps, surface water and the wetland remediation system effluent discharge point. One surface water sample was collected from surface water locationWCSW-02 at ST037. PFBS was detected at a concentration below the EPA RSL. PFOA and PFOS were detected at concentrations above the EPA HA and the ADEC groundwater cleanup level (Section 3.7.27.4 Surface Water Results SI Report for AFFF Areas. 2017). PFOS and PFOA were detected at LF04SP-02 at concentrations of 0.42 and 0.39 µg/L, respectively.
See site file for additional information.
|
Louis Howard |
| 8/28/2018 |
Offsite Soil or Groundwater Disposal Approved |
Staff approved disposal of 31 drums of investigation derived waste to a permitted facility in the lower 48 States. |
Louis Howard |
| 1/15/2019 |
Update or Other Action |
Draft 5 Year Review received for comment which include Operable Unit 5 Source Area ST037. Issue: Limited natural attenuation of COCs in groundwater (GW) is occurring at the site, indicating that RAOs may not be achieved within the projected timeline of 30 years. Recommendation: Conduct additional site characterization (SC) activities as recommended in the Data Compilation & Remedial Action Evaluation Report, Western & Eastern ST037 Plumes, August 2017. Upon completion of SC activities, data analysis should be performed to refine understanding of the plume configuration, aquifer hydraulics, & extent of source area contamination. When data evaluation is complete, prepare a treatability study proposing focused treatment based on results of the SC activities to prevent off-site migration of contaminated GW, remediate areas of saturated & smear zone soils, & reduce concentrations in the plume to expedite cleanup to ROD established levels.
Issue: Cancer risks exceed 1 x 10-4 or have an HQ greater than 1 for the following non-COC chemicals: (in GW) 1,1,2,2-PCA, naphthalene, & vanadium; (in surface water) TCE; & (in soil) total xylenes. Recommendation: Investigate, by conducting a sampling event, the following chemicals for potential inclusion as remedy COCs: (in GW) 1,1,2,2-PCA, naphthalene, & vanadium; (in surface water) TCE; & (in soil) total xylenes. Document any changes to COCs in a decision document.
ISSUE: No soil LUC is in place at ST037. Cancer risks exceed 1 x 10-4 or have an HQ greater than 1 for total xylenes in soil. Recommendation: Soil sampling should be conducted to evaluate current total xylene concentrations. Based on these findings, determine if LUCs restricting soil excavation or use at the site are warranted &, if so, document this in a decision document.
See site file for additional information. |
Louis Howard |
| 2/14/2019 |
Document, Report, or Work plan Review - other |
Staff commented on the draft five year review. Main comments were: PFAS investigation is needed to delineate the nature and extent of contamination at this source area (CS DB Hazard ID 641) in Operable Unit 5. No soil borings were installed at the seeps, therefore, this is a data gap. In 2016, four groundwater samples were collected from surface seeps OU5SP-01, OU5SP-02, OU5CP-02, and OU5SP-11. PFOA was detected at concentrations above the EPA HA, but below the ADEC cleanup level at OU5SP-01, OU5SP-02, and OU5CP-02, and at a concentration above the EPA HA and the ADEC cleanup level at OU5SP-11. PFOS was detected at a concentrations above the EPA HA, but below the ADEC cleanup level at OU5SP-02 and OU5CP-02, and above the EPA HA and ADEC cleanup level at OU5SP-11.
One surface water sample was collected from surface water location WCSW-02 at ST037. PFOA and PFOS were detected at concentrations above the EPA HA and the ADEC groundwater cleanup level.
See site file for additional information. |
Louis Howard |
| 6/14/2019 |
Update or Other Action |
ST037 SEEP ASSESSMENT REPORT ST037 – SEEPS 1 AND 2 received for review and comment. Three soil borings located further north of the pipeline (upgradient groundwater direction) had lower concentrations of petroleum hydrocarbons that did not exceed the preliminary screening levels (PAHs), which suggests that the pipeline corridor is the source of contamination in the ST037 source area. all sample results were below their respective PSLs for polynuclear aromatics hydrocarbons (PAHs) and benzene, toluene, ethylbenzene, xylenes (BTEX). Gasoline range organics (GRO) had 8 wells had five samples above table C cleanup level of 2,200 ug/L (max detect 7,100 ug/L). Diesel range organics (DRO) was detected in 7 wells above Table C cleanup level of 1,500 ug/L (max detect 28,000 ug/L).
See site file for more information. |
Louis Howard |
| 6/25/2019 |
Document, Report, or Work plan Review - other |
Staff provided comments on the draft 2019 Seep Assessment Report ST037 - Seeps 1 and 2 Dated June 2019. Main comments: Suggestion for analyses of groundwater in all wells at ST037 would be to sample for total and dissolved lead as well as ethylene dibromide (EDB) and 1,2-dichlroroethane (1,2-DCA) in future assessment follow-up monitoring.
See site file for additional information. |
Louis Howard |
| 8/21/2019 |
Document, Report, or Work plan Review - other |
Staff reviewed the annual monitoring report for select CERCLA sites. Main comments were to request the Air Force sample for perfluorinated compounds at the Western ST037 Plume, Slammer Avenue Plume and the seeps, surface water features, and the Wetland Remediation System as well as the Early Warning and Sentry Monitoring Well Network. This will require the Air Force to conduct additional investigation through a remedial investigation/feasibility study under CERCLA or as required by 18 AAC 75.335 Site Characterization (as amended through October 27, 2018) either under the existing source area or under a new site designation. This additional investigation will either take place in 2020 or more likely 2021.
See site file for additional information. |
Louis Howard |
| 4/12/2021 |
Document, Report, or Work plan Review - other |
DEC submitted comments on Draft JBER Basewide UFP-QAPP dated February 2021. |
William Schmaltz |
| 5/19/2021 |
Document, Report, or Work plan Review - other |
DEC Reviewed and approved of Basewide Uniform Federal Policy - Quality Assurance Project Plan. QAPP summarizes general activities for a 5 year period on JBER. |
William Schmaltz |
| 5/28/2021 |
Document, Report, or Work plan Review - other |
DEC Approved of Final LTM and LUC Inspection Work Plan for select CERCLA sites dated May 2021. |
William Schmaltz |
| 8/9/2021 |
Document, Report, or Work plan Review - other |
DEC staff reviewed and provided comments on Draft 2020 Land Use Control report for Select CERCLA sites dated June 2021. Report summarized LUC inspections performed in December 2020. Most sites were covered in snow and a full inspection could not be performed until spring 2021. DEC requested that the spring 2021 inspections are included in the 2020 report or as a separate cover because they are a continuation of the 2020 inspections and separate of the 2021 inspections. |
William Schmaltz |
| 2/16/2023 |
Document, Report, or Work plan Review - other |
DEC reviewed and provided comments regarding the 2023 Letter Work Plan Remedial Action Operations and Long-Term Management, Draft, dated January 2023.The work plan describes the site inspections, maintenance activities, and groundwater, seep, and surface water monitoring, at multiple sites located on Joint Base Elmendorf- Richardson (JBER), Anchorage, Alaska. The scope of work briefly summarizes the site locations, sampling/monitoring schedules, and activities such as free-product removal from monitoring wells and monitoring/maintenance activities at the Operable Unit 5 wetlands. The details regarding the procedures for the remedial action operations and long-term management activities will remain consistent with the 2021 Uniform Federal Policy Quality Assurance Project Plan (UFP-QAPP). |
Ginna Quesada |
| 4/20/2023 |
Document, Report, or Work plan Review - other |
DEC reviewed and provided comments for the 2021 Annual Remedial Action-Operations and Long-Term Management Report for Select CERCLA Sites, Draft, dated December 2023. The report describes the site inspections, maintenance activities, and groundwater monitoring, at multiple sites located on Joint Base Elmendorf- Richardson (JBER), Anchorage, Alaska. Site inspections and sampling were recommended to continue for all applicable sites to ensure that conditions remain protective of human health and the environment. |
Ginna Quesada |
| 1/29/2024 |
Document, Report, or Work plan Review - other |
DEC reviewed the 2022 Annual Remedial Action-Operations and Long-Term Management Report for Select CERCLA Sites, Draft, dated October 2023. The report describes the site inspections, maintenance activities, and groundwater monitoring, at multiple sites located on Joint Base Elmendorf- Richardson (JBER), Anchorage, Alaska. Site inspections and sampling were recommended to continue for all applicable sites to ensure that conditions remain protective of human health and the environment. |
Ginna Quesada |
| 5/18/2024 |
Document, Report, or Work plan Review - other |
DEC submitted comments regarding the 2023 Annual Remedial Action-operations And Long-term Management Report for Select State-regulated Sites Draft, Dated April 2024. The report describes the site inspections, maintenance activities, and groundwater monitoring, at multiple sites located on Joint Base Elmendorf- Richardson (JBER), Anchorage, Alaska. Site inspections were recommended to continue for all sites to ensure that conditions remain protective of human health and the environment. The report recommends updating land use controls (LUC) site boundaries at CG534, a ‘Cleanup Complete’ determination without institutional controls (ICs) for SS522, the removal of groundwater LUCs at SS041, and a ‘Cleanup Complete with ICs determination for TU101. |
Ginna Quesada |
| 6/25/2024 |
Document, Report, or Work plan Review - other |
DEC approved the 2023 Annual Remedial Action-operations And Long-term Management Report for Select State-regulated Sites Final, dated June 2024. The report describes the site inspections, maintenance activities, and groundwater monitoring, at multiple sites located on Joint Base Elmendorf- Richardson (JBER), Anchorage, Alaska. Site inspections were recommended to continue for all sites to ensure that conditions remain protective of human health and the environment. The report recommends updating land use controls (LUC) boundaries at CG534, a ‘Cleanup Complete’ determination without institutional controls (ICs) for SS522, the removal of groundwater LUCs at SS041, and a Cleanup Complete with ICs determination for TU101. |
Ginna Quesada |
| 7/2/2024 |
Document, Report, or Work plan Review - other |
DEC approved the 2022 Annual Remedial Action-Operations and Long-Term Management Report for Select CERCLA Sites, Final, dated June 2024. The report describes the site inspections, maintenance activities, and groundwater monitoring, at multiple sites located on Joint Base Elmendorf- Richardson (JBER), Anchorage, Alaska. Site inspections and sampling were recommended to continue for all applicable sites to ensure that conditions remain protective of human health and the environment. |
Ginna Quesada |
| 8/14/2024 |
Document, Report, or Work plan Review - other |
DEC provided comments regarding the ST037 Data Gap Study Management Plan Draft, dated August 2024. The work plan describes the methods for conducting a data gap study concerning the delineation of volatile organic compounds (VOCs) and poly and perfluoroalkyl substances (PFAS) at the AFFF Seep OU5 Diesel Fuel Line Site (ST037) located on Joint Base Elmendorf- Richardson (JBER), Anchorage, Alaska. The objective of the study is to delineate the middle and downgradient contamination at the Western ST037 Plume to determine the extent of the plume and to provide recommendations for future investigative efforts. |
Ginna Quesada |
| 9/19/2024 |
Document, Report, or Work plan Review - other |
DEC approved the ST037 Data Gap Study Management Plan Final, dated September 2024. The work plan describes the methods for conducting a data gap study concerning the delineation of volatile organic compounds (VOCs) and poly and perfluoroalkyl substances (PFAS) at the AFFF Seep OU5 Diesel Fuel Line Site (ST037) located on Joint Base Elmendorf- Richardson (JBER), Anchorage, Alaska. The objective of the study is to delineate the middle and downgradient contamination at the Western ST037 Plume to determine the extent of the plume and provide recommendations for future investigative efforts. |
Ginna Quesada |
| 11/12/2024 |
Document, Report, or Work plan Review - other |
DEC approved the 2023 Annual Remedial Action-Operations and Long-Term Management Report for Select CERCLA Sites, Final, dated October 2024. The report describes the site inspections, maintenance activities, and groundwater monitoring, at multiple sites located on Joint Base Elmendorf- Richardson (JBER), Anchorage, Alaska. Site inspections and sampling were recommended to continue for all applicable sites to ensure that conditions remain protective of human health and the environment. |
Ginna Quesada |
| 4/15/2025 |
Document, Report, or Work plan Review - other |
DEC provided comments for the 2024 Annual Remedial Action-Operations and Long-Term Management Report for Select State-Regulated Sites Draft, dated April 2025.The report describes the site inspections, maintenance activities, and groundwater monitoring, at multiple sites located on Joint Base Elmendorf- Richardson (JBER), Anchorage, Alaska. Site inspections were recommended to continue for the majority of the sites to ensure that conditions remain protective of human health and the environment. DEC concurs with the recommendation to close SS522 site without ICs, discontinue groundwater sampling at TU107, and reducing the sampling frequency for some wells at TU103. |
Ginna Quesada |
