| Action Date |
Action |
Description |
DEC Staff |
| 1/24/1992 |
Update or Other Action |
In 1992, Tracer Research Corporation conducted a tightness integrity test of the flight line refueling system which showed pipelines associated with Tanks 44 and 45 (both JP-4 and 50,000 gallon in capacity) have a product leak. |
Louis Howard |
| 3/27/1992 |
Update or Other Action |
Letter to Air Force Colonel Everett Mabry Spill# 92-2-1-1-017-2 re: Petroleum contamination and integrity of fuel handling system at Fac# 11-680. On 1/24/1992 the department mailed Capt. Doug Tarbet a letter regarding tightness testing of underground storage tanks at facility 11-680.
VRCA Environmental had reported petroleum contamination beneath the site and stated it was not feasible to continue testing the tanks with Tracer Test method. VRCA concluded that a fuel line associated with the 50,000 gallon underground storage tank systems (USTs) were leaking. Air Force did not concur with VRCA's conclusions and hired Pacific Northern Environmental to retest the lines and tanks. No leaks were found with a test consisting of pressurizing the lines with an inert gas and measuring the pressure in the line for a period of time. We are not aware of any third party certification of this testing method (which is required by EPA under 40 CFR 280 in order for tests' results to be accepted).
Based on the history of the site, uncertified method used for testing fuel lines, it was recommended the fuel facility be taken out of service. On 3/19/1992 it was stated that the facility would be taken out of service as soon as the product was below the top of the tanks.
The department requests: by 3/10/1992 written confirmation be provided on the three 50,000 gallon tanks and associated product lines at 11-680, by 4/24/1992 provide as-built plans showing location, configuration of tanks, lines, and valves associated with 11-680, by 4/24/1992 provide copies of all reports and written correspondence pertaining to tightness testing and site assessment/investigation work conducted at 11-680 including correspondence from VRCA environmental. |
Ron Klein |
| 3/31/1992 |
Update or Other Action |
Tightness integrity test of the Flight Line refueling system was conducted and indicated a leak in the pipeline connecting the return-to-bulk header pipe to the above ground manifold pipe. |
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 |
| 4/10/1992 |
Update or Other Action |
Letter from Air Force to Ron Klein regarding the tank tightness testing by PNE for five underground storage tanks (USTs) at 11-680. PNE testing concludes that the USTs are tight but there is some question regarding the piping system associated with the 3 50,000 gallon JP-4 tanks. Information requested in 3/27/1992 letter is included for your review. The leak detection report is preliminary and a final certified report will be forwarded upon receipt. |
Ron Klein |
| 6/5/1992 |
Document, Report, or Work plan Review - other |
Letter to Air Force from K Patrick-Riley re: USTs and proposed tracer tight testing. The department will accept results of sufficient demonstration of an intact line if any of the 3 sets of conditions are met:
1) Tracer Tight test conducted in accordance with 18 AAC 78, Tracer Tight Standard Operating manual, and with the criteria established by the method evaluation conducted by Ken Wilcox and Associates. Note that this mandates a miminum 14 day waiting time between tracer injection and collection of vapor samples.
2) In accordance with 18 AAC 78, Tracer Tight Standard Operating manual, with all injection probes installed within one foot of the pipelines at a minimum 20 foot centers, minimum waiting time in days = .5 * (max. distance in feet between any 2 adjacent probes)
3) all of 2 above but minimum waiting time is the larger of theoretical max. distance between any point in the line and a probe = .5 * (max distance in feet between any 2 adjacent probes) OR theoretically longest time Tracer A will move vertically through soil that the probe draws 2-3 inches of mercury = .5 *(distance in feet that any injection probe exceeds 1 foot of distance between pipeline and probe.) |
Kent Patrick-Riley |
| 6/29/1992 |
Update or Other Action |
A confirmatory tightness test performed in June 1992 indicated that a segment of the connecting pipeline was leaking between the above ground manifold and valve pit 3-A. Tracer test results: based on the results of the sample analyses on June 16 and 18, Pipeline 2 passes and Pipeline 3 fails the Tracer Tight Leak Test. The tracer data also indicates a leak in Pipeline 2 at Probe 5.
This connecting pipeline was excavated, and it was determined that a flange gasket was missing on the vertical section of pipe connecting the above ground manifold to the underground piping. Hydrocarbon odors and apparent hydrocarbon pooling within the excavation were reported to the appropriate Base Point of Contact. |
Louis Howard |
| 7/15/1992 |
Update or Other Action |
Repairs were completed on the pipeline and a tightness test was conducted during July 1992 and determined the repairs were acceptable. |
John Halverson |
| 8/5/1992 |
Update or Other Action |
ENSR report: Line A: ENSR completed an inspection and repair of Line A in a manner which meets or
exceeds industry standards. The subsequent integrity assessment of the pipeline repairs
was accomplished in accordance with the scope of work approved by Mr. Kent Patrick-Riley
of the ADEC in a letter dated July 23, 1992 (see Attachment 5.) It Is ENSRs opinion that the apparent pressure loss observed during the testing period can be attributed to helium gas seepage past valve seals designed for liquid petroleum products, as well as inherent inaccuracies resulting from temperature/gas pressure relationships and associated thermal expansion/contraction factors in a multi-media environment consisting of soil of various
classifications, steel pipe, steel flanges, rubber valve seals, and the like. In consideration
of these factors, ENSR believes Line A is "tight• within the sensitivity limits of the tightness
testing protocol used.
ENSR does not believe the petroleum odors detected beneath the adjacent portion of the pipeline from Valve Pit 3 to 3A are a result of a breach in this pipelines integrity. This conclusion is based on the tightness results reported by each of Pacific Northern Environmental, Inc. during their February, 1992 Integrity assessment and Tracer Research during their June, 1992 !racer Tight Leak Test.
Line B:
ENSR completed an inspection and repair of Line B in a manner which meets or exceeds Industry standards. The subsequent integrity assessment of the pipeline repairs was accomplished in accordance with the scope of work approved by Mr. Kent Patrick-Riley of the ADEC in a letter dated July 23, 1992 (see Attachment 5.)
It is ENSRs opinion that the apparent pressure loss observed during the testing period can be attributed to helium gas seepage past valve seals designed for liquid petroleum products, as well as Inherent inaccuracies resulting from temperature/gas pressure relationships and associated thermal expansion/contraction factors in a multi-media environment consisting of soil of various
classifications, steel pipe, steel flanges, rubber valve seals, and the like.
The temperature impact on the ability of liquid petroleum valves can be readily observed from the data obtained during the testing of Line B. Approximately 15 percent of Line B, including the RTB header and associated valves, are unshielded from surface weather conditions. This is in direct contrast to Line A where less than 5 percent is exposed but protected in covered, underground vaults.
Based on ENSR's soap tests and helium vapor tests on the RTB header valve in the cool morning hours, combined with the apparent average pressure drop of about 1.6 psig during the four evenings and a daytime apparent average pressure drop of about 0.4 psig during the four days, ENSR concludes that lower temperatures increase the helium gas leak rate in the liquid petroleum valves tested. In consideration of these factors, ENSR believes Line B is tight within sensitivity limits of the tightness testing protocol used.
It is ENSR's opinion that all USTs and underground piping associated with Tank Farm No. 3 have been properly tested for their tightness and repaired where required in accordance with industry standards, and where applicable, State of Alaska regulations. Therefore, Tank Farm No. 3 is available to be returned to service. |
Louis Howard |
| 10/2/1992 |
Enforcement Agreement or Order |
State Elmendorf Environmental Restoration Agreement signed. The agreement is designed to remedy environmental contamination due to past practices at the Base and avoid the expense of formal enforcement proceedings. The Air Force will perform any necessary assessment, monitoring, remediation, and closure of the sites. The agreement addresses the following program areas: solid waste, underground storage tanks (USTs), and petroleum oil and lubricants (POL) spills. |
Louis Howard |
| 3/26/1993 |
Update or Other Action |
Department of Defense and ADEC joint Technical Memorandum of understanding signed concerning the Basewide Groundwater. Signatories: ADEC SCRO-Jennifer Roberts Remedial Project Manager and USAF Joseph Williamson Chief Environmental Programs and Restoration.
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 (attachment 1-contour map). based on this information Elmendorf would like to move all upgradient groundwater into the OU5 Feasibility Study, Proposed Plan and Record of Decision. This means we would address all groundwater from upgradient sources (CERCLA (ST20, OU3, and OU4) and OUs 1 and portions of OU2) and SERA) at OU5 instead of at each individual source area (see attachment 2-Area Map). Those sites which have free phased product would be looked at to see if there is an available technology to clean them up in a cost effective way. Soil contamination would still be addressed at the source areas. NOTE: addressed at the source areas is interpreted by ADEC as removal through excavation or active treatment systems (e.g. high vacuum extraction, bioventing, etc...).
Also included in the file is the AF memo: Restricted Use of the Shallow Aquifer on Elmendorf Air Force Base (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 regulators the use of the shallow aquifer for any purpose on Elmendorf is not allowed. Please see the attached Facility Board minutes (March 29, 1994 0930-Item 9 of minutes). Mr. William Hanson, Chief of Environmental, briefed to the Facilities Board the policy to not use the shallow water aquifer due to contamination. The Facilities Board approved this policy. Minutes approved by Thomas R. Case Brigadier General USAF Commander. The Installation Restoration Program (IRP) has additional Record of Decisions (RODs) for Operable Units 3 and 6 which require, as a stipulation of the agreement with Environmental Protection Agency and Alaska Department of Environmental Conservation, this aquifer remain unused.
2) Our concern is that key personnel in the review process within Civil Engineer Squadron are aware of these policies and that these policies are reviewed on a recurring basis. It is imperative that this restriction be recognized and observed during engineer reviews and operations.
3. If you have questions on this subject, please contact Mr. Joe Williamson at 552-7229. |
Jennifer Roberts |
| 1/20/1994 |
Enforcement Agreement or Order |
Janice Adair Regional Administrator Southcentral Regional Office signs the November 29, 1993 Underground Storage Tank Agreement. The Parties enter this Agreement to perform necessary inventory,registratIon, upgrading or closure, and tightness testing associated with USTs at Elmendorf. All draft final work plans for field work must be submitted to ADEC a minimum of 30 days prior to the start of field work or construction.
Site Assessment draft reports for closures must be submitted to ADEC within 60 days after completion of field work. All reports of confirmed leaking USTs, or the need for further investigation, will be forwarded to 3 SPTG/CEVR (or its) successor organization) for possible inclusion into the SERA*. Initial abatement activities required under 18 AAC 78.230 will be conducted by the Air Force prior to transfer of any site to the SERA.
*SERA=Environmental Restoration Agreement between ADEC and the Air Force dated October 1992.
Discovered USTs-All USTs discovered during the life of this Agreement will be addressed under this Agreement and will be added to Attachment A. The Air Force will notify ADEC by next day mail of any discoverv within five days of the discovery of an UST, unless release notification is required under 18 AAC 78 220, in which case those provisions will control.
Installation: Any new USTs installed by the Air Force shall be installed in accordance with 40 CFR 280 and 18 AAC 78.022 through 18 AAC 78.090 and will have leak detection, corrosion protectlon, overfill protectIon, and spill protection. The Air Force will notify ADEC at least 30 days prior to initiating installation of an UST. UST installation work will be conducted by a certified UST worker as required by 18 AAC 78.030 and 18 AAC 78.400.
Release Detection: The Air Force shall install and perform release detection in accordance with
the schedules outlined in Attachment A. If release detection is not installed or the tank not
previously permanently closed by the date in Attachment A, the Air Force will close the tank in
accordance with the closure requirements in 18 AAC 78. All tightness testing performed to
satisfy these requirements will be conducted bv a certified UST worker as required bv 18 AAC
78.030 and 78.400
Operation and Maintenance of Corrosion Protection: The Air Force shall meet the requirements of 18 AAC 78.045 and 40 CFR 280.31 for any steel USTs, that have corrosion protection systems The testing of the corrosion protection systems shall be done by a certified UST worker as required by 18 AAC 78.400.
Site Assessment or System Tig:htness Test: The Air Force shall either conduct a system tightness test on all regulated USTs located at the Base or permanently close the USTs in accordance with Attachment A. If site assessments or system tests have been conducted, the Air Force shall submit proof of compliance by the deadlines set in Attachment A. All tightness testing work will be conducted by a certified UST worker as required by 18 AAC 78.400.
Release Investigation and Corrective Action: Release investigations, interim corrective action and corrective action on petroleum contamination identified in work conducted pursuant to this Agreement is not within the scope of this Agreement. These activities will be conducted pursuant to the Environmental Restoration Agreement between ADEC and the Air Force dated October 1992. |
Janice Adair |
| 4/21/1995 |
Update or Other Action |
AF memo: 18 April 1995 UST Meeting. Elmendorf AFB will accomplish the following actions regarding UST Projects. These actions are based upon conversation between, John Mahaffey, Larry Opperman and yourself. EAFB will make every effort to accomplish a clean closure of a UST removal site if possible.
UST removal locations requiring cleanup action will be transferred into the State-Elmendorf Environmental Restoration Agreement (SERA). A list of sites requiring cleanup will be coordinated with your office. The presumptive remedy for contaminated UST sites in the outwash plain only will be bioventing technology. Contaminated soils exceeding cleanup levels may be placed back into the excavation only if the site assessment (SA) indicates a need for further cleanup action.
Contaminated UST sites not in the outwash plain will require further investigation to determine appropriate cleanup options. We will make every attempt possible to assure new USTs or new aboveground tanks are not installed in any way that would hamper future access for cleanup. The project will first accomplish removal of all of the USTs. SA information will be used to prioritize sites for cleanup using existing project funds. Additional funding will be requested to complete cleanup if available. Sites not addressed for cleanup due to exhausted funding will be placed into SERA Phase IV. John Halverson signed on April 21, 1995. Memo was signed by Douglas G. Tarbett, Maj, USAF, Chief, Environmental Compliance. CC: 3 WG/JA and 3 SPTG/CE. |
John Halverson |
| 5/5/1995 |
Document, Report, or Work plan Review - other |
ADEC letter to Joseph Williamson and Claude Mayer RE: review comments SERA Phase II Draft Site Assessment Report March 1995. At all of the sites where residual free product was observed or groundwater contaminant concentrations are indicative of residual free product (e.g. ST32 tanks: 1, 3, 11, 17 and ST68), the monitoring wells need to be checked for measurable amounts of product. If free product is present, then product recovery methods need to be evaluated and implemented. This should reduce the time required for overall remediation and monitoring to verify whether natural attenuation will work.
1.4.1 The report states natural attenuation is the top ranked alternative for both POL contaminated soil and groundwater at EAFB. Based on our previous discussions, it is ADEC's understanding natural attenuation was not being pursued as a primary remedial alternative for petroleum in sol.
ST68: The recommendation calls for bioventing to treat soil contamination and natural attentuation of the groundwater impacts. Free product was observed in the soil during repairs of the fuel distribution system in 1992 and was observed in monitoring wells during the Phase II Site Assessment. Free product recovery methods need to be evaluated and implemented. Soil vapor extraction, possibly followed up by bioventing, appears to be more appropriate remedial alternative for the site. |
John Halverson |
| 7/27/1995 |
Update or Other Action |
It appears the contaminated soil above level "A" was removed from around the tank but, high levels of soil contamination (21, 600 ppm DRO, 1780 ppm GRO) still exist around the four dispensers and the closed (in-place closure) piping (11,600 ppm DRO & 1588 ppm GRO). |
Louis Howard |
| 7/31/1995 |
Update or Other Action |
SERA II Site Assessment. Source SS50 (formerly referrred to as Site SP-15) is located west of 22nd Street and east of 24th Street in an open area between the two streets. A 1,000 gallon avgas spill occurred at SS50 in 1961. The majority of the spill was reportedly contained and collected; however, some of the avgas seeped into the ground. The presence of benzene and petroleum hydrocarbons have been identified in the groundwater.
1990 an RI/FS Phase III, Stage 3, site investigation was conducted which included a soil gas survey and installation of 2 groundwater monitoring wells SP15-01 and SP15-02. BTEX compounds exceeding background levels were found during the soil gas survey and BTEX compounds in groundwater exceeding MCLs was attributed to the former avgas spill. Based on these findings, SS50 was selected for further investigation under SERA. The contaminants of concern are GRO and BTEX.
The investigation was successful in determining that residual contamination from the reported avgas spill at SS50 is no longer contaminating soil or groundwater. However, ST68 is implicated as a source of soil and groundwater contamination identified during the SS50 investigation.
Conclusions: Soil-The results of the SERA II investigation indicate that the only soil contamination present above the regulated levels is within the zone of seasonal groundwater fluctuation and related to the groundwater contamination that has migrated onto the site from the adjacent ST68 site.
Chromatograms of the SS50 contamination are characteristic of a middle distillate petroleum product, not light refined product such as avgas. The results of this investigation indicate that there is no soil or groundwater contamination at SS50 orginating from the former avagas spill or spoil pile. Contamination identified through SS50 investigation emantes from ST68.
Groundwater- high concentrations of petroleum hydrocarbons were found in groundwater from wells near adjacent to ST68, with visible sheens indicative of free product.
The results of this investigation suggest that ST68 is the source contributing to groundwater contamination identified at SS50 and the groundwater contamination in SP15-01 through the 1990 RI/FS. Organic lead was not detected in groundwater samples at SS50. Total lead concentrations ranged from 0.0087 and 0.3 mg/L (NOTE: 18 AAC 75 2012 Table C Groundwater Cleanup level for Lead is 0.015 mg/L).
Recommendations: On the basis of data indicating no soil or groundwater contamination at SS50 originating from the former avgas spill or spoil site, no further action is recommended for SS50. It is recommended that consideration of the groundwater contamination identified be transferred to ST68 (Bldg. 11567 Hazard ID 2746). |
Louis Howard |
| 9/4/1995 |
Update or Other Action |
SERA Phase II Site Assessment Report Final Volume received. Site contamination investigation activities began in1994 and determined the presence of petroleum contamination in soil and groundwater. ST68 is just north of N Street and west of the north-south runway adjacent to Building 11-680. This site has five active USTs: three 50,000 gallon USTS-Tanks 43, 44, and 45 (STMP 108, 109, 110) storing JP-4, one 25,000 gallon UST-Tank 42 (STMP 107) storing regular avgas, and one 12,000 gallon UST-Tank 122 (STMP 175) storing diesel fuel. No investigations were conducted at ST68 prior to March 1992. A March 1992 tightness tes of the tanks and associated piping indicated a leak in the line segment connecting the return-to-bulk header to the aboveground manifold. A tightness test performed in June 1992 indicated a segment of the pipeline was leaking between the aboveground manifold and valvel pit 3-A. The segment was excavated, and a flange gasket was missing on the vertical section of pipe connecting the aboveground manifold to the underground piping. Workers reported hydrocarbon odors and hydrocarbon pooling within the excavation. Repairs were completed on the piping during July 1992 and piping passed a tightness test.
Groundwater contamination being identified at ST68 requires the cleanup level to be "A".
The analytical results show soil contamination: DRO 770 mg/kg, GRO, 6,100 mg/kg, benzene (13 mg/kg), toluene (43 mg/kg), ethylbenzene (260 mg/kg), and xylenes (9.3 mg/kg). Three monitoring wells were installed at the site. DRO 14000 ug/L GRO 80000 ug/L Benzene at 4200 ug/L. toluene (3.4 mg/L), ethylbenzene (1.2 mg/L) and xylenes (4.4 mg/L) were detected in groundwater samples from monitoring well 65-WL-01. Free phase products were also detected in several downgradient monitoring wells.
NOTE: SS50 (formerly referred to as Site SP-15) is located west of 22nd Street and east of 24th Street. A 1,000 gallon avgas spill occurred at SS50 in 1960. SS50 has soil and groundwater contamination present with ST68 implicated. All samples with elevated petroleum hydrocarbons were collected near groundwater level or the zone of seasonal groundwater fluctuation.
The soil contamination is related to the groundwater contamination that has migrated onto the site from the adjacent ST68 site. Base well BW40 is approximately 1,600 ft. downgradient from the contamination identified at SS50. BW40 has been completed in the lower confined aquifer, which has been demonstrated through the basewide water level program not to be in communication with the upper confined aquifer.
Chromatograms of SS50 contamination are characteristic of middle distillate petroleum product, not light refined product such as avgas. The results of this investigation indicate that there is no soil or groundwater contamination at SS50 originating from the former avgas spill or spoil pile. The contamination identified through the SS50 investigation comes from Site ST68. To remediate the contaminated soil at ST68, a bioventing well, module, and soil probe network were installed in 1995. |
Jennifer Roberts |
| 9/26/1995 |
Document, Report, or Work plan Review - other |
Letter to C. Mayer Dept. of Air Force 3 SUG/CEVR RE: SERA Phase II Site Assessment Report Final July 1995.
The document was submitted as a final report, however, it includes information (bioventing treatability test results, conclusions, recommendations & other modifications) that were not in the draft. Therefore, the department considers the report a second draft or a draft-final rather than a final document & request the comments provided below be addressed.
Several UST sites within ST32 are recommended for closure or no further action is recommended based on the finding of no soil or GW contamination. However, in most cases petroleum constituents were found in soil or GW samples. The wording should be changed to state that no soil or GW contamination was found above risked based concentrations or regulatory levels defined in 18 AAC 78, unless analyses were detected in any samples from a site.
The department requests the Air Force respond to the items listed below.
Several areas within ST32 were found to have significant concentrations of petroleum compounds in the GW. The source for much of this contamination has not been determined, however, the piping network which remains in the ground appears to be the most likely source. The piping is part of the UST system. Releases have been documented from the system & proper closure is necessary as defined in the UST regulations (18 AAC 78). Additional release investigation & proper closure of the pipelines are requested
A fuel line, extending to the east of ST32, is shom1 on Figure 3.1-3B between tanks 7 & 8. Another line is shown in Figure 3.1-3A extending to the west from ST32. The assessment report does not provide information on the status of these lines. As noted in the previous comment, additional assessment & proper closure of the lines are requested to comply with the UST regulations.
Section 4.2.5 recommends closure of source area SS50 & addressing GW impacts in the area under ST68. The department does not object to this proposal. A separate closure document will need to be prepared, signed & placed in the administrative record & appropriate files.
Section 4.3.6 states that GW contamination associated with ST68 has already been addressed through OU5. However, section 4.1 states that new data acquired during the SERA Phase II investigation indicates that contamination at ST68 is approximately an order of magnitude greater than what used in the OU5 GW modeling. Based on this, & that fact that the downgradient extent of GW impacts has not been defined, the statement that GW at the site has been addressed through OU5 is incorrect & needs to be revised.
The following wells need to be monitored & evaluated for the presence of recoverable petroleum product & if product is present recovery efforts need to be implemented:
ST32 - Tank 1, monitoring well 59WL01; Tank 3, monitoring well 50WL18; Tank 11, monitoring wells 59WL04 & 59WL11; Tank 15, monitoring well 59WL23; Tank 17, monitoring well 59WL10; &, ST68- monitoring wells 62WL01, 62WL02, & 62WL03.
Additional soil borings &/or monitoring wells have been recommended to define the extent of impacts in the following areas:
ST32 - near 59WL3 l, southeast of Tank 2, southeast of Tank 5, southeast of Tank 6, southeast of Tank 7, southeast of Tank 8, northwest of Tank 17, around Tank 1, around Tank 3 (elevated GW contamination, source & extent not defined, the well shown to be downgradient has a water table elevation 12 feet lower than the well through the former tank site even though it is only 45 feet away horizontally, it's possible they may be screened in different perched lenses of water), Tank 10, Tank 11, Tank 12, upgradient of Tank 15, Tank 25, & Tank 28; ST68; &, ST74 (a potential upgradient source is referenced).
Natural attenuation, free product recovery, additional investigation, SVE & bioventing have been proposed as possible remedial alternatives for various contaminant source areas investigated under SERA Phase II. The department requests a draft scoping document be submitted outlining how (contract mechanism, narrative description & schedule) the Air Force intends to pursue corrective action at each source area. |
John Halverson |
| 11/16/1995 |
Document, Report, or Work plan Review - other |
ADEC letter to Air Force (C. Mayer) RE: SERA Phase II Site Assessment Report, ENSR's response to comments on the draft final document. The response provided still does not adequately address the comment. The report states petroleum contamination found at ST68 was an order of magnitude greater than what was used in the groundwater modeling at OU5.
The downgradient extent of the groundwater contaminant plume has not been defined. It is unclear how an extrapolation of this was done to conclude the modeling has sufficiently evaluated the potential for future migration and risk to downgradient receptors. Supporting information needs to be provided or the section needs to be reworded. It should state that long-term groundwater monitoring is necessary to evaluate whether the modeled plume degradation represents actual site conditions. |
John Halverson |
| 11/17/1995 |
Document, Report, or Work plan Review - other |
Letter from ADEC to Dept. of Air Force (C. Mayer) RE: Comments on Radian's "Basewide Support for bioventing Studies SERA Phase II Sites Work Plan" and "Pre-final (90%) Design Submittal".
Work Plan-Section 2.3 describes source area ST68. It states that there are three 50,000 gallon USTs, used to store JP-4, at the site. The tanks stored JP-4 up until about 1992, and since then have contained JP-8. If releases have occurred since the change in fuels, JP-8 would be a contaminant of concern.
Source area ST68 was identified as having high concentrations of gaoline range organics (GRO) in the soil and LNAPL on the water table. The SERA Phase II site assessment report recommends evaluation of free product recovery and soil remediation by soil vapor extraction followed by bioventing. The work plan does not address product recovery or SVE. This is an issue that needs to be addressed. |
John Halverson |
| 12/11/1995 |
Update or Other Action |
Memo from Dept. of AIr Force, 3 SPTG/CEVR for ADEC John Halverson Subject: SERA Phase II Site Assessment Report Final, July 1995.
1. Our response to the Air Force action items identified in your September 26, 1995 letter are:
a) Ref. item 1 and 2). Our understanding is additional release investigation and removal of the pipelines and valve pits within ST32 is required. This effort would have to be programmed as a future project. Our estimate in getting this work done is complete Remedial Design in FY 97 with the Remedial Action accompished in FY 98. Also, it should be noted that a MCP project FXSB 963013, West Ramp Hydrant Fueling System will impact ST32. Our review comments on this project have requested the removal of pipelines and valve pits within the construction area of this project.
b. Ref. item 3). The GW monitoring program was changed to include the SERA Phase II sites. The wells included are listed: 62WL05, 62WL06, 49WL01, ST20-03, 62WL07, 64WL01, 59WL31, 59WL36, 59WL37, 59WL38, 59WL30, 59WL29, 59WL35, 59WL42, 59WL43, 59WL39, 59WL40, 59WL41, 48WL01, 62WL02
C. Ref. item 4). We will prepare separate closure document for SS50. Our goal is to have closure documents completed by March 1996.
d. Ref. item 5) Compliance section is aware of the UST identified at site SS49. Tank is being incorporated into a future project. Mr. Larry Opperman is working this action item.
e. Ref. item 6) The pump for BW50 was removed after it was discovered to be screened in the shallow aquifer during the OU6 RI/FS. Reference section 7.0 of the OU6 RI/FS Draft/Final. On page 7-48 under recommendations it stated Media (soil & GW) Recommended No Further Action. Therefore, there are no contaminate sources present which could threaten the supply well.
f. Ref. item 7) Radian is under contract to evaluate passive fuel recovery at ST68. The ST32 monitoring wells will be added to Radian's contract. Our request for additional dollars for Radian's efforts at ST32 is being coordinated.
g. Ref. item 8) The data gaps have been addressed in bioventing basewide project for SERA Phase II sites. The new wells are: ST68-62WL05, 62WL06, 62WL07. These are downgradient wells for ST68. ST32-59WL36, 59WL37, 59WL38, 59WL35, 59WL42, 59WL43, 59WL39, 59WL40, and 59WL41. These are compliance wells on the edge of the moraine.
h. Ref. item 9) The outline on pursuing corrective action at each SERA Phase II Source area:
ST32-NFA tanks: 9, 13, 14, 18, 19, 21, 22, 23, 26, 27, 29. MNA Tanks 1, 3, 10, 11, 12, 15, 16, 20, 24, 25 and 28.
Request being worked for additional dollars to accomplish/look into free product recovery at 59WL01 (Tank 1), 50WL18 (Tank 3), 59WL04 (tank 11), 59WL11 (tank 11) and 59WL23 (tank 15).
Recommend bioventing Tanks 2, 4, 5, 6, 7, 8 and 17. Systems scheduled to be running late December 1995/January 1996.
Request being worked for additional dollars to accomplish/look into free product recovery for 59WL10 (tank 17).
See site file for additional information. |
John Halverson |
| 2/29/1996 |
Leaking Underground Storage Tank Corrective Action Underway |
Bioventing system is operational for petroleum contamination at site. |
Louis Howard |
| 7/2/1996 |
Update or Other Action |
Technical Memorandum for Bioslurping Technology (Radian Intl. to AFCEE R. Garland) stated six wells at ST68 were listed for bioslurping bail-down testing to determine whether free product could be recovered. In the June-July 1996 timeframe, all of the wells were checked for measurable free product. At that time, none of the wells at ST68 contained measurable free product. |
Louis Howard |
| 8/26/1996 |
Update or Other Action |
Letter from Hugh C. Cameron Brigadier General USAF Commander to Jim Hayden. Thanks for your letter dated July 24, 1996 concerning the inadvertant mailing of Notice of Violation (NOV) letters. As you know, we take our environmental responsibilities very seriously and appreciate the high level of cooperation between the Base and your Department. This has allowed us to focus on our environmental issues and has led to many environmental improvements at Elmendorf. |
Louis Howard |
| 9/5/1996 |
Update or Other Action |
Technical Memorandum for Bioslurping Technology (Radian Intl. to AFCEE R. Garland) stated six wells at ST68 were listed for bioslurping bail-down testing to determine whether free product could be recovered. All of the wells were sampled again for free product. The September results again indicated none of the wells at ST68 contained measurable free product; therefore, a bail-down test was not performed at the ST68 wells. |
Louis Howard |
| 12/31/1996 |
Document, Report, or Work plan Review - other |
Staff provided comments on the technical memorandum "SOP for Closing Bioventing Systems on the Glacial Outwash Plain at EAFB" dated November 14, 1996. Project managers from ADEC, the EPA, and EAFB agreed that attempting to develop a correlation between monitoring data and closure sampling would be beneficial. If a good correlation is shown to exist, then developing a closure procedure based on monitoring data should be possible. Since there has been extensive site investigation and monitoring work done on EAFB, this appears to be a reasonable alternative. It would reduce sampling costs associated with having to do subsurface soil confirmation sampling at every bioventing site in the outwash plain.
To decide whether this will be a feasible alternative, it will be necessary to identify the number of sites with various types of petroleum contamination; conduct bioventing system monitoring and respiration testing along with confirmation soil sampling at a representative number of the sites; and show a good correlation between the monitoring data and the soil sample results. To do this, ADEC requests a list be prepared showing the number of bioventing sites currently operating or proposed. The site list should be broken down into categories for gasoline range organics (GRO), diesel range organics (DRO), and residual range organics (RRO). ADEC requests 25% of the sites under each category, with a minimum of 10 from each be included in the confirmation soil sampling sites to decide if a good correlation can be developed. If less than 10 sites exist under any category (i.e. RRO) confirmation sampling should be done at each site in that category rather than pursuing an alternative closure process for them.
At Page 3, under "problem definition", it refers to relatively small volumes of contaminated soil commonly treated at the Base through bioventing. It states that once the obviously contaminated soil around an underground storage tank has been removed, the remaining contaminated soil is often in a relatively shallow and even layer. The basis for these statements is not clear. In many cases, when USTs were removed, contaminated soil was placed back into the ground. Since most outwash plain consists of coarse grained soil with a low organic carbon content, most of the releases have resulted in contaminate migration down to the groundwater.
Table #3 Footnote #1 refers to respiration testing between June 15 and September 30. It is likely that some frost may remain in the ground during June. Also, if sufficient biological activity is generated, the soil temperatures would remain elevated later into the year. Therefore, ADEC recommends respiration testing be conducted later in the year (i.e. between July 15 and November 15).
Figure 2 does not include fields for helium injection and monitoring during respiration tests. These should be included to evaluate whether short circuiting may be occurring. Average air flow rates at each venting well should also be reported. This may help indicate whether soil moisture may be a limiting factor due to drying of the soil during bioventing. The depth and screen length of soil implants should be provided on the form to simplify the review process. |
John Halverson |
| 2/11/1997 |
Site Added to Database |
Site added by Shannon and Wilson, Inc. |
S&W-Miner |
| 6/3/1997 |
Update or Other Action |
Work plan for ST68 received. One soil boring will be drilled in the area of highest contamination at ST68 to determine the currently existing conditions in the soil. The new soil boring location was also chosen because it is the most active bioventing well in the SERA II Study. Monitoring well 64WL-01 will not be sampled during this project since this well is scheduled for periodic sampling under the Basewide Support and Groundwater Monitoring Program this spring (1998).
The "Basewide Support for Bioventing Studies SERA Phase II Sites Workplan" which addressed installing treatment systems at ST32 (several, but not at all of the tank sites), ST66, ST68, and ST74. The plan is the corrective action plan for those sites. |
Louis Howard |
| 2/27/1998 |
Update or Other Action |
A limited field investigation was performed at ST68 in 1997 to determine remaining contaminant concentrations. This investigation included advancement of one soil boring near monitoring well 64WL-01. The sample collected from 22.5 feet bgs, was analyzed for DRO, GRO, and BTEX.
Only benzene and toluene were above the cleanup levels for the site at 0.1 mg/kg and 6.1 mg/kg, respectively; the remaining contaminants were below cleanup levels. These contaminant concentrations had decreased considerably from concentrations detected during the 1994 SERA Phase II investigation. The report recommended that bioventing continue at the site. |
Louis Howard |
| 3/16/1998 |
Document, Report, or Work plan Review - other |
ADEC sent comment letter to USAF RE: SERA Phase II Bioventing Remediation Monitoring Annual Report. Source Area ST68 page 4-7
The recommendations state that bioventing should continue and DEC concurs. DEC reserves the right to comment on the SERA risk assessment and its appropriateness for use at this site. |
Louis Howard |
| 6/30/1998 |
Update or Other Action |
Air Force Technical Document to support no further action declaration. Site SS50, AVGAS Spill Site located west of 22nd Street and east of 24th Street in an open area between the two streets. Based on the current conditions at Environmental Restoration Program (ERP) Site SS50, no further action (NFA) at this site is required under the ERP.
The results of the SERA II investigation indicate that the only soil contamination present above the regulated levels is within the zone of seasonal groundwater fluctuation and related to the groundwater contamination that has migrated onto the site from the adjacent ST68 site. High concentrations of petroleum hydrocarbons were found in groundwater from wells near adjacent SERA site ST68, with visible sheens indicative of free product.
The results of this investigation suggest that ST68 is the source of contamination contributing to groundwater contamination identified at SS50. Elevated concentrations of BTEX, DRO, and GRO were detected in soil samples collected from 62BH07, and all monitoring wells except 62WL04. All samples with elevated petroleum hydrocarbon concentrations were collected near groundwater level. The sample collected from 23.5 feet bgs had the highest contaminant concentrations.
Detectable concentrations of BTEX and GRO were indicated in groundwater samples collected from well SP15-01 and all wells installed in 1994 (62WL01, 62WL02,62WL03, and 62WL04). Contaminant concentrations in all wells except for 62WL04 exceeded the federal MCL for benzene (5 [ig/L). Contaminant concentrations in wells 62WL01,62WL02, and 62WL03 were at concentrations indicative of LNAPL.
Additionally, chromatograms of SS50 contamination are characteristic of middle distillate petroleum product, not light refined product such as avgas. The results of this investigation indicated there is no soil or groundwater contamination at SS50 originating from the former AVGAS spill or spoil pile. Contamination identified through the SS50 investigation emanates from ST68. |
Louis Howard |
| 12/7/1999 |
Institutional Control Record Established |
No current receptors exist for the groundwater at the Base due to the institutional controls (ICs). As a requirement of previously signed RODs for Operable Units (OUs) at the Base, ICs have been established to restrict the use of the shallow aquifer in the outwash plain on Base for both SERA and CERCLA sites. These restrictions are enforced through the Base Comprehensive Plan (BCP).
Projects and other activities are reviewed during the planning stage to ensure compliance with the BCP. In addition, construction projects and other activities also undergo an environmental review. This review helps ensures compliance with groundwater use restrictions. |
Louis Howard |
| 12/7/1999 |
Long Term Monitoring Established |
The SERA II Round 2 monitoring well results were received. Benzene detected at well 64-WL-01 130 ug/L and DRO at 4.26 mg/L. Well 62-WL-05 had GRO at 18 mg/L and benzene at 480 ug/L Benzene levels at wells 59-WL-36, 62-WL-05, and 64-WL-01 increased slightly during round 2. 3 remaining wells exceeded the benzene MCL during round 2 1999 sampling, remained the same at 59-WL-31 and decreased slightly at 60-WL-04 and ST20-03. Groundwater sampling has been occurring since 1994 at this site. |
Louis Howard |
| 1/10/2000 |
Update or Other Action |
10/99-12/99 Quarterly report received. Of the 34 wells sampled 11 wells remain above the MCL for benzene. Groundwater cleanup levels for petroleum constituents are estimated to be met in September 2010. |
Louis Howard |
| 1/24/2000 |
Update or Other Action |
Bioventing report received for basewide long-term operation and maintenance of systems. For the purposes of final closure sampling, the required minimum number of samples will be three per boring-at the area with the highest PID reading, at the highest historical contaminant level and at soil/groundwater interface. Analysis of BTEX, DRO and GRO contaminants of concern (PAHs if following Method Two) will be required. |
Louis Howard |
| 2/11/2000 |
Document, Report, or Work plan Review - other |
Staff reviewed and commented on the Draft Basewide Bioventing System report, dated January 2000. DEC concurs with most of the recommendations for ST43/55. For negotiating cleanup levels beyond the Level A criteria, DEC will consider adopting the cleanup criteria in 18 AAC 75. However, this move to a Method 2 cleanup level will require more analytical work on the Air Force's part to show the site has achieved cleanup levels. 18 AAC75.325 (g) states: If using method two or method three for determining the applicable soil cleanup levels as described in 18 AAC 75.340 - 18 AAC 75.341, or if applying the groundwater cleanup levels at Table C in 18 AAC 75.345, a responsible person shall ensure that, after completing site cleanup, the risk from hazardous substances does not exceed a cumulative carcinogenic risk standard of 1 in 100,000 across all exposure pathways and a cumulative noncarcinogenic risk standard at a hazard index of 1.0 for each exposure pathway.
While it is correct that the cleanup levels found in Table B2: "Under 40-inch Zone" is 300 mg/kg GRO and 250 mg/kg DRO, the Air Force must also comply with the note no. 15 to Tables B Method Two Soil Cleanup Levels Table and Petroleum Hydrocarbon Soil Cleanup Levels B2. If using method two, the applicable petroleum hydrocarbon cleanup levels must be met in addition to the applicable chemical-specific cleanup levels for: benzene, toluene, ethylbenzene, and total xylenes (BTEX) and PAHs. |
Louis Howard |
| 4/17/2000 |
Document, Report, or Work plan Review - other |
Staff reviewed and commented on draft Basewide Bioventing Systems Biweekly monitoring and soil gas respiration testing annual report. 1996-1999 Respiration tests: Respiration tests were conducted in 1996-1999 to measure biodegradation rates. In 1999, biodegradation rates were measured at 0 to 111 mg/kg/year.
For the purposes of final closure sampling, the required minimum number of samples (from a minimum of three borings) will be three per boring-at the area with the highest PID reading, at the highest historical contaminant level and at soil/groundwater interface. ADEC will require analysis of benzene, toluene, ethylbenzene, and total xylenes (BTEX), diesel range organics (DRO) and gasoline range organics (GRO) contaminants of concern (sampling for PAHs will be required if the Air Force chooses to cleanup under Method Two). Laboratory analyses, where applicable, will utilize approved AK lab methods, i.e. AK 101 and 102. |
Louis Howard |
| 6/28/2000 |
Offsite Soil or Groundwater Disposal Approved |
Request by the Air Force to thermally treat contaminated soil from the drilling efforts at ST68. Based on the sampling results, the Air Force proposes to bulk the soil and transport the bulked materials to Alaska Soil Recycling for thermal treatment and disposal of the treated soil. The department concurred. |
Janice Adair |
| 7/11/2000 |
Document, Report, or Work plan Review - other |
Staff reviewed work plan for closure confirmation sampling for ST68, ST32, ST61, and ST32 bioventing sites. Plan approved as submitted. Three closure soil borings to be completed per site and three samples taken per boring to confirm whether or not clean closure can be determined. |
Louis Howard |
| 9/22/2000 |
Update or Other Action |
2000 Round 1 Basewide groundwater monitoring results received. Methyl tert-butyl ether (MTBE) added to the list of analytes at ADEC's request. No MTBE was detected in any of the wells. Benzene was detected in 64-WL-01 at 62 ug/L. This is a decrease from 1999 when the spring sampling detected 86 ug/L and fall sampling detected 130 ug/L of benzene. |
Louis Howard |
| 12/8/2000 |
Update or Other Action |
Basewide Monitoring SERA Phase II Round 2 results received. 62 WL-05 benzene results remained steady at 230 ug/L for rounds 1 and 2. 64-WL-01 benzene levels went from 62 ug/L in round 1 to 60 ug/L in round 2. 62-WL-05 GRO levels in rounds 1 and 2 remained steady at 15,000 ug/L. DRO levels remained below 1,500 ug/L in rounds 1 and 2. |
Louis Howard |
| 1/3/2001 |
Update or Other Action |
Historic contamination extends from 12 to 32 feet bgs; therefore the three boreholes were advanced to 33 feet bgs. Borings: 64BH03, 64BH04, 64BH05 were advanced and nine soil samples were collected and anlyzed for DRO, GRO, and BTEX to determine remaining contaminant concentrations. Because previous subsurface investigations at this site inidcated that the vertical extent of contamination extended from 12 to 31 feet bgs, the three boreholes were advanced to 33 ft. to encompass the full extent of contamination. Depth intervals were screened with a PID and the interval with the highest PID reading, an interval with historic contamination and the interval just above the groundwater were collected for lab analysis.
Local depth to groundwater is approximately 25 feet bgs with the "smear zone" (The smear zone is defined as the range of depths within which the groundwater will fluctuate under normal seasonal conditions, and therefore, in which free product would move and “smear” the soil in response to these seasonal changes in the water level elevation. The smear zone soils may therefore be saturated or unsaturated with groundwater at any given time.) extending to 21 feet bgs. Soils at the site (especially 64BH05) need to be resampled to show that the contamination is below site closure criterion (ACM Level "D"). Groundwater will require sampling and will need to be below MCLs for 4 consecutive events (two years) before no further action determination can be considered. |
Louis Howard |
| 4/3/2001 |
Document, Report, or Work plan Review - other |
Staff reviewed and commented on the Air Force's Response to Comments Draft Year 2000 Biovent Closure Effort, Elmendorf Air Force Base, AK, dated 22 March, 2001. Some of these comments have been previously submitted in a January 3, 2001 letter on the “Draft 2000 Bioventing Closure Effort, 30 November 2000” and a March 21, 2001 letter on “Draft 2000 Bioventing Annual Report, Elmendorf Air Force Base, AK, dated 28 February, 2001.
There are specific regulations, which allow ADEC to require the Air Force to conduct periodic sampling of soils when bioventing systems are shutdown. Please refer to 18 AAC 75.345(h) and (i), which are applicable to include soils at: ST 32 Tank 4, ST 32 Tank 5, ST 32 Tank 6, ST 61, and ST 68.
(h) ADEC will require long-term monitoring if ADEC determines monitoring is necessary to ensure protection of human health, safety, or welfare, or of the environment and if groundwater, surface water, soil, or sediment contains residual concentrations of a hazardous substance that exceed the applicable cleanup levels. If long-term monitoring is required under this subsection, the USAF shall submit a plan and schedule for monitoring as part of the requirements for cleanup operations under 18 AAC 75.360. Unless otherwise approved by ADEC, the USAF shall conduct monitoring quarterly for at least one year to establish the concentration trend. ADEC will evaluate the monitoring program yearly. If the monitoring indicates that the concentration trend
(1) is increasing, ADEC will require additional followup monitoring and assess the need for additional cleanup; or
(2) is stable or decreasing, and that hazardous substance migration is not occurring, ADEC will decrease or discontinue the monitoring frequency and locations, if the USAF demonstrates that continued monitoring is not necessary to ensure protection of human health, safety, and welfare, and of the environment.
For the purposes of monitoring soil contamination at the above sites, ADEC is requesting the soil be sampled every three years to verify degradation of the contaminants present at the sites. If there were other timeframes the Air Force wishes to discuss, ADEC would be willing to meet and discuss them. These sites will not be considered “closed” until the applicable cleanup levels are met. |
Louis Howard |
| 3/7/2002 |
Document, Report, or Work plan Review - other |
Staff reviewed and commented on the Basewide Bioventing report for 2001.
General Comments
Decommissioning Bioventing Systems
Where the Air Force is recommending bioventing systems be decommissioned, the Department requests additional clarification if the Air Force has looked at other alternatives to treat the smear zone contamination and found it was not practicable to implement them. The basis for not being practicable can be due to reasons such as: reliability of the alternative, alternative is not cost effective, site location, logistics in light of overall project purposes.
If an analysis of alternatives was conducted, then it should be stated it is not practicable due to the incremental cost of implementing an alternative is substantial and disproportionate to the incremental degree of protection provided by the alternative as compared to another lower cost alternative.
Well Log Submittal
The Department also wishes to inform the Air Force of the well log recording requirement by the Alaska Department of Natural Resources (ADNR), Division of Mining, Land and Water. The requirement is referenced in the Underground Storage Tank (UST) Procedure Manual, Section 4.7.1 Installing groundwater monitoring wells. Alaska statutes: 38.05.020, 38.05.035, 41.08.020, 46.15.020 and regulations 11 AAC 93.140 require a log of the well be submitted to the ADNR within 45 days after installing a well.
The Department concurs with the recommendations in the document for ST 68. |
Louis Howard |
| 10/21/2002 |
Update or Other Action |
J. Roberts sent a letter to Joe Williamson dissolving the State Elmendorf Environmental Restoration Agreement. The Alaska Department of Environmental Conservation (DEC) has reviewed the issue of abolishing the State Elmendorf Environmental Restoration Agreement (SERA) per your recommendation. Elmendorf Air Force Base and DEC entered into the SERA in 1992. The agreement was developed as a tool to bring the Base into compliance with Alaska's regulations addressing underground storage tanks, oil and other hazardous substance releases and solid waste.
Since that time, Elmendorf has made significant progress in investigating and cleaning up historic contamination problems. Many of the sites covered by the SERA have been successfully cleaned up and closed. Cleanup is underway at the remaining sites.
Additionally, Alaska has amended the regulations addressing fuel storage tanks, oil and other hazardous substance spills and solid waste. We concur with you that the SERA is no longer a necessary or beneficial. This letter serves as notice that DEC will end oversight on environmental work at Elmendorf by using the SERA. Instead, it is understood that the sites and programs formerly addressed by SERA: solid waste, underground storage tanks (UST), and oil and other hazardous substance discharges will be addressed in accordance with 18 AAC 60, 18 AAC 78 and 18 AAC 75. |
Jennifer Roberts |
| 1/31/2003 |
Update or Other Action |
2002 Annual Report Basewide Environmental Monitoring Program Draft January 2003 received. Note to file under:
ARARs
This data-reporting category addresses groundwater 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 groundwater COCs were not specifically identified in previous investigations (SERA and 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 and the quality of data improves with new methods. For instance, as natural attenuation occurs, select constituents will reach cleanup levels and 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.
The three SERA Phase II Program locations where groundwater sampling occurs include: ST32, ST48, and ST68, as identified in the Site Assessment Report for SERA Phase II. |
Louis Howard |
| 6/24/2004 |
Update or Other Action |
Letter from the department approving the draft decision document for ST68. The document records the Air Force's decision to terminate the use and remove the existing bioventing system located at ST68 and allow the residual contaminants to remain at the site and naturally attenuate.
Analysis of the existing data shows the bioventing system in place at ST68 does not appear to be adequately remediating the smear zone soils in the area. One conclusion is this could be due to the recontamination in the soils by contaminated groundwater. Also bioventing is ineffective in treating contamination within the smear zones due to the lack of ability to force water from within the soil pore spaces and replace it with oxygen.
Continued operation would not increase the contamination in the smear zone, a reduction of contaminant levels in groundwater corresponds directly to a reduced level of contamination in the smear zone. It is well documented that natural attenuation of groundwater in and around the ST68 source area is occurring as monitoring wells have shown a consistent decrease in contaminant levels over time. |
Louis Howard |
| 7/16/2004 |
Update or Other Action |
2003 Annual Tech report Environmental Monitoring and System Optimization of Basewide Bioventing Systems. ST68 cleanup standards: DRO 2000 mg/kg, GRO 1000 mg/kg, benzene 0.02 mg/kg, toluene 5.4 mg/kg, ethylbenzene 5.5 mg/kg and total xylenes 78 mg/kg.
Historical: Closure sampling was conducted at ST68 during 2000. The data suggest that
contamination is present only in isolated areas and quickly dissipates outside of the localized
area. Conclusions in the Year 2000 Bioventing Closure Effort Report suggest continued
bioventing is unlikely to result in the reduction of hydrocarbons below the soil cleanup levels. ADEC concurred with shutdown of the bioventing system, provided that
ongoing monitoring of soil and groundwater is performed.
Recommendations: A Decision Document was developed for ST68 to record the USAF
decision to shut down the bioventing system and allow contaminants at this location to naturally attenuate. The Decision Document is being finalized at this time. |
Louis Howard |
| 3/1/2005 |
Document, Report, or Work plan Review - other |
Staff reviewed and commented on the basewide bioventing systems annual technical report. One soil boring (64BH06) was advanced during the 2004 site investigation at ST68 and one soil sample plus a field duplicate were collected and analyzed for GRO and BTEX to determine remaining contaminant concentrations. The boring was advanced as close as possible to boring 64BH01, and the samples collected from a depth of 16 ft. bgs, where elevated concentrations of GRO and BTEX were found above the smear zone at this location during the 1994 investigation. The 2004 results combined with the 2000 site investigation confirmed that GRO and BTEX concentrations no longer exceed cleanup levels in vadose zone soils.
The Department concurs that the bioventing system for this site be shut down and removed. The groundwater will be monitored at in-source well 64-WL-01 and downgradient well 62-WL-02 under the Basewide Groundwater Monitoring Program. |
Louis Howard |
| 3/10/2005 |
Document, Report, or Work plan Review - other |
Staff reviewed and commented on the draft soil sampling report for bioventing system at ST68. ADEC concurs with the recommendations that the bioventing system be shut down and removed since the remaining soil contamination is confined to the smear zone at ST68. The location of the smear zone is approximately at 21 to 25 feet bgs. Groundwater should continue to be monitored by monitored natural attenuation. |
Louis Howard |
| 3/21/2005 |
Update or Other Action |
2004 Phase I RPO Annual Report (Draft Final) Groundwater Performance Optimization Monitoring Program received. Performance monitoring should continue to verify that these COC concentrations continue to show a decreasing trend. To optimize performance monitoring at this plume, it is recommended that the following evaluations be performed on the ST68 Plume:
COC monitoring: COC monitoring for this plume is currently performed at four wells. An evaluation of monitoring network optimization software was performed in Section 2.3. MAROS was identified as the most capable software to guide optimization of the COC monitoring networks for this Program. MAROS requires at least four wells for network optimization and six to determine proper sampling frequencies. Although the ST68 Plume meets requirements for network optimization, the site consists of two areas of contamination monitored by only two wells each.
Therefore, network optimization by using MAROS is not appropriate for this site. Monitoring network optimization and sampling frequencies should continue to be determined by using the decision guides presented in Appendix H.
Contaminant mass calculations: Although the ST68 Plume is monitored by four wells, the minimum required by MAROS, the site consists of two separate plumes, monitored by two wells. MAROS is not capable of analyzing data from these plumes separately. Because the ST68 Plume is essentially two plumes monitored by two wells each, there are not enough existing data points to calculate the contaminant mass of the ST68 plumes. Therefore, contaminant mass calculations are not recommended for the ST68 Plume.
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 ST68 Plume. As explained in Section 5.6.2.3, the wells used to monitor the ST68 plumes are too far apart to produce accurate MNA conclusions. The installation of additional monitoring wells at this plume to perform an accurate MNA assessment is not recommended.
Cleanup date predictions: It is recommended that a cleanup date for the ST68 plumes be predicted by using SourceDK Tier 1. Tier 1 is the desired choice because ST68 is an active bioventing site and is essentially two plumes, monitored by two wells each. The more complex, source-mass-based Tier 2 is not designed to account for in-source remediation technologies. Milestones should be established manually once the predicted cleanup date is known.
Bioventing treatment system: Bioventing processes have been ongoing for several years at the ST68 Plume and have been conducted to reduce smear zone contaminants. Although COC concentrations at two of the four Program wells used to monitor this plume currently exceed cleanup levels, a decreasing trend for benzene and GRO at the ST68 Plume is apparent. It is uncertain whether this decline is attributable to natural attenuation, the bioventing system, or a combination of the two. Regardless, COC concentrations are progressing toward their required cleanup levels and the bioventing system is reaching the end of its remedial capabilities. Because respiration rates have declined, it is recommended that the bioventing system at the ST68 Plume be shut down and the remedy for this plume transition to MNA for groundwater contaminants.
Remedy protectiveness summary: Although bioventing has been the soil remedy for the ST68 Plume, it is recommended that MNA for groundwater become the remedy for this plume. These remedies should be considered protective of human health and the environment. Bioventing has effectively reduced COC concentrations in soil. 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 |
| 4/1/2005 |
Document, Report, or Work plan Review - other |
The Alaska Department of Environmental Conservation (ADEC) received the 2004 Phase I RPO Annual Report (Draft Final) Groundwater Performance Optimization Monitoring Program 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 |
| 5/19/2006 |
Update or Other Action |
Future well maintenance recommendations from the 2005 Annual Basewide Groundwater Monitoring Field Report. Two separate plumes are associated with ST68: one at 64WL-01 and one at 62WL-05. Each plume is isolated with the extent of contamination found only at the in-source location. Two downgradient wells, 62WL-02 and 62WL-06, are also monitored. At 62WL06 it is recommended for abandonment or mechanical repair, concrete wellhead is damaged and the casing is bent. |
Louis Howard |
| 10/30/2006 |
Conditional Closure Approved |
Staff received the draft final decision document for ST68. Based on the information provided, staff recommended the document go final. The document finalizes ADEC's concurrence on the Air Force's recommendations to not require further remedial action at the site based on 2000 and 2004 soil sampling results from various soil borings advanced at the site. These soil sampling results have consistently shown no exceedances of the most stringent soil cleanup levels at the site. Groundwater will continue to be monitored until 18 AAC 75 Table "C" cleanup levels have been met. Institutional controls have been in place for several years base-wide regarding groundwater use in the shallow aquifer at contaminated sites. |
Louis Howard |
| 7/3/2007 |
Update or Other Action |
Dec. Document for ST68
Final Project Completion and Reopener Clause
Upon completion of the remedy termination procedure outline in Section 5.5.2 of this Decision
Document, final project completion will follow guidelines outlined in ADEC 18 AAC 75.380(c).
ADEC will determine final compliance with the applicable soil and groundwater cleanup
standards.
After reviewing the final cleanup report for ST68, if ADEC determines that the site has been
adequately characterized under ADEC 18 AAC 75.335 and has achieved the applicable
requirements under the site cleanup rules, the ADEC will issue a written determination that the
cleanup is complete. This determination will be subject to a future department determination
that the cleanup is not protective of human health, safety, or welfare, or of the environment.
While the State has jurisdiction over POL-contaminated sites, the final closure decision will be
supported by a cooperative interagency process. Should ADEC find that the cleanup and
applicable LUCs are not protective of human health, safety, or welfare, or of the environment,
the ADEC will require, as necessary to ensure protection of human health, safety, or welfare, or
of the environment, a responsible person to conduct additional actions that meet the requirements
of the site cleanup standards.
Alaska Department of Environmental Conservation hereby approves this Decision Document
and acknowledges that this cleanup remedy satisfies State laws and regulations. The Department
is basing its decision on the most current and complete data provided by the Air Force. The
Department reserves its rights, under 18 AAC 75 Oil and Other Hazardous Substances, Pollution
Control regulations and Alaska Statute 46.03, to require additional investigation, cleanup, or
containment if subsequent information indicates that: 1) additional contamination that was
previously undiscovered remains at the site and presents an unacceptable risk to human, health,
safety, or welfare, or the environment; or 2) the information provided was invalid, incomplete, or fraudulent. |
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 remedy for ST68 includes MNA and LUCs specified in a DD finalized in 2007. The COCs identified for Site ST68 were benzene and GRO. ST68 is monitored by 4 wells (2 wells are on an annual basis, 1 well on a five year basis and 1 well on a 2 year basis).
|
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.
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 |
| 8/21/2009 |
Update or Other Action |
Draft Work Plan for OT092 Fuel Pipeline and SS43/ST68 Bioventing Systems Decommissioning received.
OT092 included multiple segments of buried fuel pipeline that transported diesel fuel from the
Port of Anchorage to and around Elmendorf AFB during the 1940s to 1990s. These pipeline
segments total approximately 27,000 linear feet and include valve pits. On 15 April 1998,
OT092 was validated under the Environmental Restoration Program. The results of a limited
site assessment were reported in 1999 and included a general remedial design. OT092 is considered a state program site because the expected contaminants are petroleum products. However, because no releases are known to have occurred, no Decision Document has been produced for OT092.
In 1993, site SS43 was investigated under a Superfund Emergency Response Actions (SERA) Phase I assessment, which identified gasoline-range organics (GRO), diesel-range organics (DRO), and benzene, toluene, ethylbenzene, and xylenes (BTEX) as contaminants in soil and groundwater. In 1995, a corrective action plan recommended bioventing as the soil remedy and monitored natural attenuation (MNA) as the groundwater remedy. In 1996, the bioventing system started operating. 2003 soil sampling showed that GRO,DRO, and BTEX concentrations no longer exceed cleanup levels above the smear zone. Because the vadose zone is clean, the only soil contamination remaining is in the smear zone,where bioventing is not effective; therefore, the bioventing system at SS043 will be decommissioned in accordance with state regulations.
Soil field screening samples will be collected from the floor and sidewalls of the excavations
at a rate of 1 per 100 square feet of area (10-foot by 10-foot grid). Field screening will be used to guide the excavations and help segregate the clean overburden stockpile from contaminated soil. The SAP (Appendix B) presents additional field screening information. Confirmation sampling will begin once excavation and field screening are completed.
Excavations will be sampled at a frequency of one confirmation soil sample per 250 square feet, with two soil samples from the first 250 square feet of excavated area. At least one sample will be collected from the floor of each excavation. For excavation of pipeline segments, at least one sample will be collected from each 50 linear feet of excavated area. Confirmation soil samples will be collected at the location of the highest field screening results, at the frequency specified above. Samples will be collected and submitted to an approved laboratory for analysis. Samples will be analyzed for GRO, DRO, and BTEX.
Clean Stockpile Sampling-Soil sampling from the clean soil stockpiles will be performed in accordance with 18 AAC 78 and as described in the SAP (Appendix B). Field screening samples will be collected from the stockpiles at a minimum frequency of one per 25 cy. Analytical confirmation soil samples will be collected from random locations within the stockpile, with a frequency of one sample per 50 cy of stockpile and two samples from the first 50 cy. Analytical samples will be submitted to an approved laboratory and analyzed for GRO, DRO, and BTEX.
Valve Pit Sampling-At least two soil samples will be collected to assess conditions at each valve pit location. If excavation is necessary to expose the valve pits and decommission pipeline segments, then the valve pit area will be sampled and backfilled as detailed in Section 2.7.2. If the valve pit is accessible at grade and no excavation is required, the valve pit area will be inspected visually, and surficial soils will be field screened inside and outside of the valve pit. Field screening data and visual observations will be used to guide the collection of soil samples in and around the valve pits. Analytical samples will be analyzed for GRO, DRO, and BTEX, in accordance with the SAP (Appendix B). |
Louis Howard |
| 8/25/2009 |
Document, Report, or Work plan Review - other |
Draft Work Plan OT092 Fuel Pipeline & SS43/ST68 Bioventing Systems Decommissioning August 2009 comment letter sent to the AF. ADEC, Contaminated Sites Program, Federal Facilities Oversight staff received the above document for review & comment on August 21, 2009 via electronic mail. The message requested comments by September 4, 2009. ADEC will, as a courtesy to the AF, review the document as requested in the abbreviated time period. This will not & should not be expected as the normal time frame for reviews. At least thirty (30) days is typically required for ADEC staff to adequately review & comment on draft work plans/documents. Below are ADEC’s expedited comments on the document.
1.2 Scope of Work Page 1-2: The text states 375 tons or 250 cubic yards of soil will be removed. ADEC expects a subsequent work plan will be developed for review & comment should the volume of soil far exceeds 250 cubic yards which the contractor is unable to address.
2.2.4 Segment End Access Page 2-5: The text states: “Clean excavated soil shall be segregated from contaminated soil on the basis of field screening results.” ADEC will require the “clean” stockpile be sampled to verify the field screening results are actually below cleanup levels since field screening shall not substitute for actual laboratory analyses. Lack of a response by field screening shall not preclude the AF or its contractor from the need to sample soil & analyze for contaminants. It appears that the soil will be sampled (per 2.7.3). This is acceptable to ADEC.
2.2.5 Segment Removal Page 2-5: The text states: “All excavated soil shall be assessed for the presence of fuel contamination. Soil that is free of contamination may be used to backfill the excavation immediately upon completion of an environmental site assessment.” ADEC will require that laboratory analyses from the “clean” stockpiles be used as the basis for determining whether it should be used for backfill or remediated. Field screening results shall not be used as a substitute for laboratory analyses to determine whether or not soil is free of contamination. It appears that the soil will be sampled (per 2.7.3). This is acceptable to ADEC.
2.7.1 Field Screening Page 2-24: The text states: “Soil field screening samples will be collected from the floor & sidewalls of the excavations at a rate of 1 per 100 square feet of area (10-foot by 10-foot grid). Field screening will be used to guide the excavations & help segregate the clean overburden stockpile from contaminated soil.” A photoionization detector (PID) is not to be substituted for laboratory analyses to confirm whether or not overburden is “clean” or “contaminated”.
2.7.2 Excavation Confirmation Sampling Page 2-24: The text states: “Confirmation soil samples will be collected at the location of the highest field screening results, at the frequency specified above.” Absent a positive response with the field screening device, ADEC expects the field sampling to be based on where contamination is expected to be found, i.e. near valve pits, hot taps, joints of pipeline segments, elbows & lastly best professional judgment by the “qualified person”. At no time, will lack of field screening results preclude the AF from collecting the required number of samples.
3.1 Remedial Action Completion Report Page 3-1: The text states that a remedial action completion report will be prepared in accordance with 18 AAC 75.335(c). ADEC requests the AF ensure the report is prepared & signed by the qualified person. If it is meant to be a final report, then the applicable portions of 18 AAC 75.380 Final reporting requirements & site closure must also be included in the remedial action completion report.
3.1 Field Screening Page B-3-1: The text states the PID will be used to perform headspace soil sample field screening. ADEC requests the AF clarify whether the PID will be operated with a lamp source that is able to detect the contaminants of concern, operates at a minimum of 10.6 eV, & is capable of ionizing those contaminants of concern.
The text states the soil will be warmed before reading headspace vapors. ADEC UST Procedure Manual at 4.4.2 Headspace Analytical Screening Procedure for Field Screening (4) states: “...the temperatures of the headspace must be warmed to at least 40 degrees F (approximately 5 degrees C), with instruments calibrated for the temperature used.” ADEC requests the AF change to the text in the document to reflect the minimum temperature for headspace & calibration requirement.
Upon incorporation of ADEC comments, the work plan is approved by ADEC. ADEC’s review & approval of this work plan is to ensure the work is done in accordance with State of Alaska environmental conservation laws & regulations. ADEC’s approval of the plan does not relieve responsible persons from the need to comply with other applicable laws & regulations. |
Louis Howard |
| 10/15/2009 |
Meeting or Teleconference Held |
A meeting of the remedial project managers (RPMs) convened at 0900 on 15 October 2009 in the CEAN Conference Room, Building 5312, at Elmendorf Air Force Base (EAFB), Alaska. Attendees included: Mr. Jacques Gusmano (Environmental Protection Agency [EPA]), Mr. Louis Howard (Alaska Department of Environmental Conservation [ADEC]), Mr. Don Aide (CEANR), Ms. Donna Baumler (CEANR), Mr. Gary Fink (CEAN), Ms. Melissa Markell (CEANR), and Ms. Renee Wright (3 WG/PA).
Zones 2 and 3, SS22 Updates (Ms. Markell)
(1) Parsons is changing project managers for the Zones 2 and 3 contracts from Bill Plaehn to Steve Brauner.
(2) CEANR has changed the RPM for Zone 2 from Melissa Markell to Don Aide. The boundary for Zone 2 has been changed to encompass ST48 and ST68 as these are flightline support area sites with fuel contamination similar to other Zone 2 sites.
(3) A map with sample results and proposed sampling areas for ST32 was distributed (Attachment 6). The map represents what was happening in the middle of the 2009 field season, where more extensive contamination than anticipated was found at ST32 and the plan to install permanent monitoring wells was replaced with a plan to collect groundwater grab samples. This map was distributed to provide a preview of what will be discussed in the annual report regarding the field efforts for 2009. More investigation, an updated conceptual site model, and new sampling program recommendations are anticipated for ST32 in the next few years.
(4) A summary of the biovent decommissioning at FT23 was distributed (Attachment 7). Mr. Fink thanked EPA and ADEC for the quick response and concurrence that allowed this decommissioning to occur. Ms. Markell explained that while the soil remediation had concluded at FT23, groundwater was still being monitored and the soil vapor investigation conducted in summer 2009 could lead to more soil vapor work, including installation of more soil vapor monitoring points. Preliminary soil vapor and groundwater monitoring results were not available for this meeting.
(5) A proposal to continue the Wetland Remediation System Optimization Study was distributed (Attachment 8). Analytical results to date were attached, showing that all sample results have been below cleanup levels. Ms. Markell read through the proposal, emphasizing that if the study continued and a need to reactivate pumping was realized during the winter, a temporary pump and conveyance line would be used since the existing system would be unusable until spring 2010. If the study results indicate that cleanup levels are being met using the passive collection and drainage system, use of passive treatment would be proposed for the duration of the remedy. Mr. Gusmano stated that this proposal was acceptable only because a back-up system would be in place; without the ability to reinstate pumping, it would be hard to concur. Mr. Howard agreed.
(6) Updates to the SS22 schedule for the FFA are under review. These proposed new dates will be sent to the agencies for review and concurrence within the next couple of weeks. A Triad meeting to plan the investigation work for 2010 will be scheduled in the 2-23 November timeframe. EPA and ADEC will provide their available dates to assist in scheduling.
(7) The draft memorandum on interim LUCs at SS22 is in internal review. This memo is expected to be sent for agency review within a few weeks. The memo does not fully cover all interim LUCs at SS22 because the possession-only permit is still pending from the Radioactive Isotope Committee (RIC) Secretariat. The current version of the memo includes descriptions of the dig permit process, health physics monitoring, and fencing. Once the permit is received, details on signage requirements and other LUCs will be specified; another memo will be issued to describe these interim LUCs. |
Louis Howard |
| 2/16/2010 |
Update or Other Action |
Staff received the draft 2009 Zone 3 Management Area Annual Report Environmental Restoration Program. Site ST68 is a State Program site northwest of the Heritage Park area, along Slammer & Sijan Avenues in the southern portion of Zone 2. Prior to 2010, Site ST68 was discussed in documents for the Zone 3 Management Area. Beginning in 2010, this site is discussed in documents for the Zone 2 Management Area because the boundary between the Zone 2 & Zone 3 Management Areas was revised during the 2009 field season.
GW samples were collected from wells 62WL-02 & 64WL-01 on 24 June 2009 & were submitted to a fixed-base laboratory for analysis of BTEX & GRO. Benzene measured in duplicate samples collected from 62WL-02 (6.9J/8.0J ug/L) were above the 5 ug/L cleanup level, & GRO levels (3,100/3,000 ug/L) were above both the DD cleanup level of 1,300 ug/L & the revised ADEC cleanup level of 2,200 ug/L. No other VOCs exceeded state cleanup levels.
Biogeochemical indicator parameters measured in GW from the ST68 Plumes indicate a moderately anaerobic environment. Conditions at well 64WL-01 are similar to those observed in 2008, while DO & ORP data collected for 62WL-02 in 2009 (0.30 milligram per liter [mg/L] & -93.5 millivolts (mV), respectively) suggest a slightly more anaerobic & reducing environment than was indicated by data collected in 2008 (0.79 mg/L & -64.5 mV, respectively). Overall, the range of individual parameter values for the ST68 Plumes in 2009, & the corresponding interpretation of the active electron acceptor processes, are consistent with expectations for conditions within a petroleum hydrocarbon plume (i.e., conditions are oxygen depleted). In terms of COC degradation, petroleum hydrocarbons degrade under anaerobic conditions at rates that are significant, but slower than what would typically occur in an aerobic environment
The 2007 RPO evaluation identified the ST68 Plume (64WL-01) as a Green priority site because it is on track to reach cleanup levels. The 2009 results for 64WL-01 are below cleanup levels & are consistent with historical results. However, results for 62WL-02 indicated that both benzene (6.9J/8J µg/L) & GRO (3,100/3,000J µg/L) were above their respective cleanup levels of 5 µg/L & 1,300 µg/L, indicating that the core of the 64WL-01 may have moved downgradient from that well. Because 2009 was the first year that COC levels have been above cleanup levels in well 62WL-02 since 1998, the Green priority designation for the 64WL-01 plume remains appropriate. A priority change may be recommended in the future if benzene & GRO concentrations in well 62WL-02 continue to increase or remain stable.
The 2007 RPO evaluation identified the ST68 Plume (62WL-05) as a Yellow priority site because GRO levels are not expected to reach cleanup levels by the end date of 2025 stated in the DD. Well 62WL-05 was not sampled in 2009; therefore, the Yellow priority remains appropriate. COC levels measured in well 64WL-01 have been below cleanup levels for 3 consecutive years, indicating that it can be removed from the sampling program.
No further sampling is recommended at 64WL-01, & this well can be considered for future abandonment. The ADEC GW cleanup level for GRO was updated in 2008 to 2,200 ug/L. Formal modification of the 2007 Decision Document to match the current GRO standard should be implemented when practicable. |
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 for review and 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 groundwater plumes and 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) and ST68 (CS DB Hazard ID 2746).
5.4 Summary and Recommendations Page 5-4
The text states: “The ADEC groundwater cleanup level for GRO was updated in 2008 to 2,200 µg/L (ADEC, 2008). Formal modification of the DD to match the current GRO standard should be implemented when practicable.” ADEC concurs.
ADEC review and comment on this draft report and appendices is to ensure that the work is done in accordance with State of Alaska environmental conservation laws and regulations. While ADEC may comment on other state and federal laws and regulations, our comments on the document does not relieve the Air Force from the need to comply with other applicable laws and regulations.
|
Louis Howard |
| 3/10/2010 |
Update or Other Action |
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.
5.4 Summary and Recommendations, Page 5-4 EPA agrees with updating the GRO standard. |
Louis Howard |
| 12/2/2010 |
Update or Other Action |
Letter Report for the Treatment System Removal at SS43, ST32 Tank 7, and ST68 received.
Site ST68 is located along Slammer and Sijan Avenues, northwest of the Heritage Park area. In March 1992, a tightness test of the tanks and associated piping at Tank Farm No. 3 indicated a leak in one of the lines. Excavation and repairs were undertaken, at which time hydrocarbon odors and apparent hydrocarbon pooling within the excavation were reported. Repairs were completed in July 1992. In 1994, a site assessment was conducted. The assessment identified BTEX, GRO, and DRO as the COCs. Recommendations included Monitored Natural Attenuation for groundwater and bioventing for soil. Bioventing began in 1996.
Sampling efforts in 2004 showed that BTEX and GRO concentrations in the soil no longer
exceeded cleanup levels above the smear zone, and the bioventing system was recommended
for decommissioning.
Decommissioning activities occurred over two days in 2009 (16 through 17 September) and
were completed in 2010 (12 through 14 July). The objectives for the bioventing system
removal at SS43, ST32, and ST68 sites were removing the biovent system, disconnecting the
electrical utility panel, and salvaging the treatment system blower and filter unit. All work
was performed in accordance with the OT92 Fuel Pipeline and SS43/ST68 Bioventing Systems
Decommissioning Work Plan.
Decommissioning consisted of de-energizing the system, and removing the blower and filter
units and enclosures, aboveground and underground piping, injection wells, vapor monitoring
probes, electrical panels, and other system components. All decommissioning activities were
performed in accordance with Alaska Department of Environmental Conservation (ADEC)
regulations 18 Alaska Administrative Code (AAC) 80 (ADEC 2009) and ADEC guidance
(ADEC 1992).
Prior to removing the bioventing systems, utilities were located, and a qualified electrician
isolated the equipment from the electrical supply at the freestanding electrical panel near the
blower box. The blower and filter units were identified for salvage in the Work Plan (USAF
2009) and transported to the Defense Reutilization and Marketing Office (DRMO) yard on
Davis Highway after decommissioning. Wells were decommissioned using a Volvo BL60 backhoe to lift the outer casing and concrete monument. Removal of the outer casing and monument allowed for direct access to the inner 2-inch polyvinyl chloride (PVC) casing. The boring holes were filled with a slurry of bentonite and water to within 1 foot of the ground surface. Surface completion of the site was accomplished by using local fill material and a vegetative mat to bring the area to local grade. Asphalt was used as the final surface after removal of vapor monitoring probes in paved areas of the ST68 treatment system.
SS43: The blower assembly, three injection wells, and five vapor monitoring probes were
decommissioned (Figure 2-1).
ST32 Tank 7: The blower assembly, one injection well, and four vapor monitoring probes were decommissioned. The field team was unable to disassemble the electrical connections from the utility box to the CONEX; therefore, the utility box was left in place.
SS68: Two blower assemblies, six vapor monitoring probes, and three injection wells were decommissioned (Figure 2-3). One soil probe (BV-68-2A) was not located during fieldwork and is most likely covered by the paved surface at the expected location.
Attachment 1 presents photographs of associated site activities. Attachment 2 contains the
treatment system equipment receipts from DRMO. Several sections of PVC piping associated
with the bioventing system were disposed of at the Anchorage Municipal Landfill.
Decommissioning activities were completed in accordance with the OT92 Fuel Pipeline and
SS43/ST68 Bioventing Systems Decommissioning Work Plan (USAF 2009). These tasks included decommissioning of the bioventing system wells and associated piping, removal of the vapor monitoring probes, and removal of blower and filter units. Re-usable treatment system components were salvaged and transported to the DRMO, including the freestanding blower and filter units. The electrical utility panel remains at the ST32 Tank 7 site. |
Louis Howard |
| 1/24/2011 |
Update or Other Action |
Staff received the 2010 Zone 2 Mgt Area Annual Report.
Site ST68 contamination is associated with a pipeline leak between an aboveground manifold and a valve pit. Minor soil and substantial groundwater contamination were initially identified. A bioventing system began operating in 1996 to remediate the impacted vadose zone soil (USAF, 1999). Data collected during a 2000 site investigation indicated that the bioventing
system had achieved its full potential and no further remediation was possible through this system. ADEC (2001) concurred with shutting down the bioventing system if ongoing monitoring of the groundwater continued.
Historically, two areas of groundwater contamination were associated with this site and were monitored separately by wells 64WL-01 and 62WL-05. Two wells downgradient of the former ST68 Plumes (62WL-02 and 62WL-06) were used to monitor the area. However, analytical results for well 62WL-02 in 2009 showed that both benzene and GRO were above their respective cleanup levels of 5 µg/L and 1,300 µg/L for the first time since 1998. These data indicated that the downgradient portion of the former 64WL-01 Plume was most likely comingled with the 62WL-05 Plume.
Based on these results, the extent of Site ST68 groundwater contamination was revised to show a single ST68 Plume that includes wells 62WL-02 and 62WL-05, rather than the two distinct plumes that had been depicted historically (USAF, 2010c). Well 62WL23 -06 continues to serve as the downgradient monitoring well for Site ST68.
ST68: CONCLUSIONS-The 2007 RPO evaluation (USAF, 2008b) identified the ST48 plume as a Green priority because concentrations were below ADEC groundwater cleanup levels. However, wells 60WL-05 and 60WL-06 were installed in 2008 and 2009, respectively, to improve the existing monitoring well network. GRO concentrations measured in 2009 at both wells exceeded ADEC groundwater cleanup levels (Figure 10.1). Because there were insufficient data points from these two wells to develop trends to estimate a cleanup date for the site, the site designation for ST48 was changed from Green to Yellow (USAF, 2010c).
GRO concentrations in well 60WL-05, the in-plume well, were higher in 2010 (7,200 µg/L) than in 2009 (5,300J / 5,000J µg/L), and there are still too few data points to develop trends to estimate a cleanup date. Therefore, the Yellow designation remains appropriate.
Preparation of a draft DD for groundwater at Site ST48 is recommended. Available data suggests that GRO will be the only COC that exceeds applicable cleanup levels. To support the final DD, continued annual sampling of 60WL-05 and 60WL-06 in 2011 is recommended to develop an estimated time frame for cleanup using an MNA-based approach.
The 2007 RPO evaluation (USAF, 2008) included two plumes at Site ST68, the 64WL-01 Plume and the 62WL-05 Plume. However, 2009 groundwater monitoring results indicated that the two plumes identified in the RPO evaluation were likely comingled, and the site model was revised to show one plume rather than the two distinct plumes that had been depicted historically. The revised ST68 plume was given a Yellow priority designation based on GRO concentrations in well 62WL-05 that are not expected to reach cleanup levels by the end date of 2025 as stated in the DD (USAF, 2010c).
Analytical results from 2010 at well 62WL-02 indicated that both benzene (10 µg/L) and GRO (6,300 µg/L) concentrations were above their respective cleanup levels of 5 µg/L and 1,300 µg/L and were both higher than concentrations measured in samples collected at this well in 2009. Well 62WL-05 was not sampled in 2010, so no additional estimates can be made regarding a cleanup date. Therefore, the Yellow priority for the Site ST68 Plume remains appropriate.
The ADEC groundwater cleanup level for GRO was updated in 2008 to 2,200 ug/L (ADEC, 2008). Formal modification of the DD to match the current GRO standard should be implemented when practicable. |
Louis Howard |
| 7/15/2011 |
Update or Other Action |
Draft Work Plan Environmental Remedial Action-Operations & LTM & Maintenance received.
The purpose of this project is to perform RA-O & LTM activities for several JBER Programs. These programs include sites distributed across both JBER-Elmendorf & JBER-Richardson. This Work Plan addresses remedial activities in JBER-Elmendorf Zone 1, Zone 2, & Zone 3 Management Areas, JBER-Elmendorf Compliance Restoration Program (CRP) sites, the JBER Elmendorf Operable Unit (OU) 1 Landfill, JBER-Richardson Multiple Installation Restoration Program (IRP) Sites, & JBER-Richardson Poleline Road & OUE Armored Vehicle Maintenance Area (AVMA).
Currently there are ten active sites within the Zone 2 Management Area: FT23, SD15, SD24, SD25, SD28, SD29, SS43, ST32, ST48, & ST68. The OU4 ROD (USAF, 1995a) specifies the selected remedy for Sites FT23, SD24, SD25, SD28, & SD29. Currently, LUCs are used at all OU4 sites until cleanup levels are met, & GW monitoring is performed at Sites FT23 & SD25. At Site SD15, 149 an ESD; to the OU 6 ROD (USAF, 1997) transitioned the remedy for this site to monitored natural attenuation (MNA). The remedial approach for Site SS43 is described in the State-Elmendorf Environmental Restoration Agreement (SERA) Phase I Corrective Action Plan, & currently consists of natural attenuation with free product removal. The selected remedy for soils with contamination in excess of cleanup levels at Site ST32 is limited hot spot removal with off-site low-temperature thermal desorption.
A final remedy for GW at Sites ST32 & ST48 has not been established. The remedy for ST68 includes MNA & LUCs specified in a DD that was finalized in 2007. Impacted media at the Zone 2 Management Area sites includes soil & GW. COCs identified for Zone 2 sites include trichloroethene (TCE); tetrachloroethene (PCE); 1,1,1-trichloroethane (1,1,1-TCA); 1,1,2-TCA; 1,2-dichloroethane (1,2-DCA); 1,1-dichloroethene (1,1-DCE); 1,2-DCE; 1,1,2,2-tetrachloroethane (1,1,2,2-PCA); benzene, toluene, ethylbenzene, & total xylenes (BTEX); DRO; & gasoline-range organics (GRO).
The overall objectives of RA-O activities within the Zone 2 Management Area are to monitor the rate of natural attenuation within GW plumes, determine the effectiveness & protectiveness of the site remedies (currently MNA for all sites), & manage all waste according to state & federal regulations.
ST68, Fuel Line Leak at Tank Farm 3: Site ST68 is located just north of N Street and west of the north-south runway adjacent to Building 11-680. This site has five active USTs as follows:
• Three 50,000-galion registered USTs (tanks 43,44, and 45; STMP numbers 108, 109, and 110) storing JP-4;
• One 25,000-galion registered UST (tank 42; STMP number 107) storing regular avgas;
• One 12,000-galion UST (tank 122; STMP number 175) storing diesel fuel.
A March 1992 tightness test of the tanks and associated piping indicated a leak in the line segment connecting the return-to bulk header to the aboveground manifold. A tightness test performed in June 1992 indicated that a segment of the pipeline was leaking between the aboveground manifold and valve pit 3-A. This segment was excavated, and a flange gasket was missing on the vertical section of pipe connecting the aboveground manifold to the underground piping. Workers reported hydrocarbon odors and apparent hydrocarbon pooling within the excavation. Repairs were completed on the piping during July 1992, and the piping passed a tightness test.
The Zone 2 Management Area sites are located throughout the central portion of JBER-Elmendorf. The southern boundary of Zone 2 is parallel to the southern edge of the east/west instrument runway. The WP presents the site locations, associated sources, & plumes. Ten sites & 12 GW plumes are located within this management area, as follows (analytes shown exceeded cleanup levels during the most recent monitoring event):
• Site FT23 (2 plumes) - TCE & PCE
• Site SD15 - benzene & TCE
• Site SD24 - benzene
• Site SD25 - toluene & benzene
• Site SD28 - TCE & PCE
• Site SD 29 - TCE & PCE
• Site SS43 - benzene, gasoline range organics (GRO), DRO
• Site ST32 (2 plumes) - benzene, GRO, & DRO
• Site ST48 - GRO
• Site ST68 (2 plumes) - benzene & GRO |
Louis Howard |
| 4/10/2012 |
Update or Other Action |
Draft 2011 Annual Monitoring Report received. Currently there are ten active sites within the Zone 2 Management Area: FT23, SD15, SD24, SD25, SD28, SD29, SS43, ST32, ST48, and ST68.
The Site ST68 DD identified GRO and benzene as the COCs in Site ST68 groundwater and established cleanup levels, as shown in Table 3.42. Although the ADEC cleanup level for GRO in groundwater was updated in 2008 to 2,200 µg/L (ADEC, 2011), the numerical standard defined in the DD for GRO remains at 1,300 µg/L because this concentration is stated in the DD.
The benzene concentration measured in the sample collected from 62WL-02 (10 mg/L) was above the 5 mg/L cleanup level, and the GRO concentration (5,700 mg/L) was above both the DD cleanup level of 1,300 mg/L and the revised ADEC cleanup level of 2,200 mg/L. No other VOCs exceeded state cleanup levels. The benzene concentrations measured at 62WL-02 in 2011 were equivalent to the 2010 result which were both higher than those measured in 2009 and significantly higher than concentrations measured in this well between 1999 and 2008, during which time benzene concentrations did not exceed 2.8 mg/L. GRO concentrations measured at 62WL-02 in 2011 were just below those measured in 2010 and significantly higher than concentrations measured in this well between 1999 and 2008, during which time GRO concentrations were 1,000 mg/L or less.
As can be observed from the GRO data for 62WL-02 and 62WL-05 (Figure 3.23), GRO concentrations have varied over time from concentrations that were more than an order of magnitude below applicable standards to concentrations an order of magnitude or more above applicable standards. The observed pattern of concentration variability over time suggests that petroleum-related contamination has been entering Site ST68 groundwater as a pulsed, rather than continuous, source and from comingling with another plume.
The 2007 RPO Evaluation Report (USAF, 2008g) included two plumes at Site ST68, the 64WL-01 Plume and the 62WL-05 Plume. However, 2009 groundwater monitoring results indicated that the two plumes identified in the RPO evaluation were likely comingled, and the site model was revised to show one plume rather than the two distinct plumes that had been depicted historically. The revised ST68 plume was given a Yellow priority designation based on GRO concentrations in well 62WL-05 that are not expected to reach cleanup levels by the end date of 2025 as stated in the DD (USAF, 2007e).
Analytical results from 2010 and 2011 at well 62WL-02 indicated that both benzene (10 µg/L each year) and GRO (6,300 and 5,700 µg/L) concentrations were above their respective cleanup levels of 5 µg/L and 1,300 µg/L and were both higher than concentrations measured in samples collected at this well in 2009. Therefore, the Yellow priority for the Site ST68 Plume remains appropriate.
The ADEC groundwater cleanup level for GRO was updated in 2008 to 2,200 µg /L (ADEC, 2011). Formal modification of the DD to match the current GRO standard should be implemented when practicable. |
Louis Howard |
| 11/30/2012 |
Update or Other Action |
Final Preliminary Project Management Plan
Table 2-1
Summary of Site Performance Objective and Performance Indicators
ST068 (0009EX) JP-4 Line, Historic Spills (IRP)
Performance Objective (PO)
Optimized Exit Strategy to achieve Site Closure
Performance Indicators
• Prepare an approved Site Characterization Work Plan by August 2013
• Perform 2012 RA-O Monitoring Event under Addendum to Current LTM Plan with approved Annual RA-O Monitoring Event Memo by February 2013
• Coordinate, mobilize, and execute Characterization Investigation concurrently with 2013 RA-O Monitoring Event by September 2013
• Prepare an approved Site Characterization Summary Report by January 2014
• Continue RA-O Monitoring to meet DD and ADEC requirements
• Prepare and implement an approved OES Report to achieve SC by February 2020
Potential Risks
Plume characterization indicates plume does not meet strategy parameters
Risk Mitigation
Evaluation of the plume dynamics will be made to identify appropriate treatment (In-Situ Chemical Oxidation)
Treatment will be implemented to bring plume into steady state achieving Cleanup Complete with Institutional Controls.
NOTE TO FILE: Site has achieved CC with ICs already as of October 2006. |
Louis Howard |
| 4/30/2013 |
Update or Other Action |
Draft Annual Monitoring Report received for review and comment.
Historically, two areas of groundwater contamination were associated with this site and were monitored separately by wells 64WL-01 and 62WL-05. Two wells downgradient of the former ST068 Plumes (62WL-02 and 62WL-06) were used to monitor the area. In 2009, analytical results for well 62WL-02 showed that both benzene and GRO were above the respective cleanup levels of 5 µg/L and 1,300 µg/L for the first time since 1998. The data indicated that the downgradient portion of the former 64WL-01 Plume was most likely comingled with the 62WL-05 plume. Based on these results, the extent of Site ST068 groundwater contamination was revised to show a single ST068 Plume that includes wells 62WL-02 and 62WL-05, rather than the two distinct plumes that had been depicted historically.
The DD for Site ST068 was executed in 2007 (USAF, 2007e) and identified GRO and benzene as the COCs. Although the ADEC cleanup criterion for GRO in groundwater was updated in 2008 to 2,200 µg/L, the numerical standard as defined by the DD for GRO is 1,300 µg/L. Current monitoring requirements at ST068 include groundwater sampling for GRO and benzene at groundwater monitoring wells 62WL-02 (annual), and 62WL-05 (every 5 years).
In 2012, monitoring wells 62WL-02 and 62WL-05 were sampled for GRO, benzene, and VPH. A field duplicate VPH sample was also collected at 62WL-05. VPH was included for future use in calculating risk at the site using the HRC. GRO exceeded the DD cleanup criterion in both wells. Benzene exceeded the DD cleanup criterion in well 62WL-05.
Additional investigation to characterize the current presence/absence of soil contamination is being proposed for ST068 under the new PBR contract. No changes to the annual monitoring are being proposed for this site. |
Louis Howard |
| 5/28/2013 |
Document, Report, or Work plan Review - other |
Staff provided comments on the 2012 Annual Report which included site "ST068". This Annual Report summarizes the environmental activities conducted in 2012 that support sampling, analysis, system operations and maintenance (O&M), and ensure full compliance with applicable federal and State regulations. Many of the sites are guided by remedial action requirements as specified in the Decision Document (DD) for each site. The overall project objectives included collecting sufficient data to:
• Monitor concentrations of contaminants of concern (COC) at each site with sufficient precision and accuracy to evaluate their concentrations with respect to cleanup goals;
• Identify potentially toxic and/or mobile transformation products;
• Monitor the rates of natural attenuation of each plume, predict cleanup dates, and compare predicted cleanup dates to compliance dates presented in the applicable DD;
• Verify individual plumes characteristics, such as downgradient, lateral, or vertical expansion or retraction;
• Evaluate groundwater flow directions and hydraulic gradients to monitor plume migration and assess contaminant sources;
• Evaluate the effectiveness of land use controls/institutional controls (LUCs/ICs) to protect human health and the environment;
• Identify and repair damaged monitoring wells to protect groundwater; and
• Identify monitoring wells that are no longer needed or are damaged beyond repair.
2012 Field Activities and Results
The text states: “In 2012, monitoring wells 62WL-02 and 62WL-05 were sampled for GRO, benzene, and VPH. A field duplicate VPH sample was also collected at 62WL-05. VPH was included for future use in calculating risk at the site using the HRC. GRO exceeded the DD cleanup criterion in both wells. Benzene exceeded the DD cleanup criterion in well 62WL-05.”
HRC risk-based cleanup levels for petroleum hydrocarbons are applicable only for those allowed by regulation for Method Three - 18 AAC 75.340(e):
alternative soil cleanup levels for the
[1] “migration to groundwater” or
[2] “inhalation” pathways based on site specific soil data, or
alternative soil cleanup levels for the
[3] “direct contact/ingestion” or
[4] “inhalation” pathways based on an approved industrial land use scenario.
The Site Cleanup Rules for Method Three do not allow for changes to Table C groundwater cleanup levels or calculation of risk based groundwater cleanup levels. ADEC will not recognize the use of HRC for calculation of risk of groundwater contamination at any site on JBER-E or JBER-R, except through the use of Method Four [risk assessment as allowed by 18 AAC 75.325(h)]. Therefore, Table C Groundwater Cleanup levels will apply with no alternative groundwater cleanup levels allowed via Method Three (e.g. HRC) for all PBR sites on JBER-R and JBR-E. The promulgated regulations will take precedence over any conflict with what is stated in the regulations vs. technical memorandum or guidance.
Site Summary
The text states: “Additional investigation to characterize the current presence/absence of soil contamination is being proposed for ST068 under the new PBR contract. No changes to the annual monitoring are being proposed for this site.”
ADEC has no additional comments regarding ST068 for this document since comments will have or have been provided on the PBR UFP-QAPP developed for this site. |
Louis Howard |
| 6/10/2013 |
Exposure Tracking Model Ranking |
Initial ranking with ETM completed for source area id: 73722 name: auto-generated pm edit Elmendorf ST68 Bldg 11567 |
Louis Howard |
| 3/13/2014 |
Update or Other Action |
Draft 2013 Annual report received for review and comment. The overall project objectives included collecting sufficient data to:
• Monitor concentrations of contaminants of concern (COCs) at each site with sufficient precision and accuracy to evaluate their concentrations with respect to cleanup goals.
• Identify potentially toxic and/or mobile transformation products.
• Verify individual plume characteristics, such as downgradient, lateral, or vertical expansion or retraction.
• Evaluate groundwater flow directions and hydraulic gradients to monitor plume migration and assess contaminant sources.
• Evaluate the effectiveness of land use controls/ institutional controls (LUCs/ICs) to protect human health and the environment.
• Identify and repair damaged monitoring wells to protect groundwater.
• Identify monitoring wells that are no longer needed or are damaged beyond repair.
Historically, two areas of groundwater contamination were associated with this site and were
monitored separately by wells 64WL-01 and 62WL-05. Two wells downgradient of the former
ST068 Plumes (62WL-02 and 62WL-06) were used to monitor the area. In 2009, analytical
results for well 62WL-02 showed that both benzene and GRO were above the respective cleanup
levels of 5 µg/L and 1,300 µg/L for the first time since 1998. The data indicated that the
downgradient portion of the former 64WL-01 Plume was most likely comingled with the
62WL-05 plume. Based on these results, the extent of ST068 groundwater contamination was
revised to show a single ST068 Plume that includes wells 62WL-02 and 62WL-05, rather than
the two distinct plumes that had been depicted historically.
The DD for ST068 was executed in 2007 (USAF, 2007e) and identified GRO and benzene as the
COCs. Although the 18 AAC 75 Table C cleanup criteria for GRO in groundwater was updated
in 2008 to 2,200 µg/L, the numerical standard as defined by the DD for GRO is 1,300 µg/L.
Current monitoring requirements at ST068 include groundwater sampling for GRO and benzene
at groundwater monitoring wells 62WL-02 (annual), and 62WL-05 (every 5 years).
During 2013, monitoring well 62WL-02R was sampled for GRO and benzene. Neither GRO nor
benzene exceeded their ST068 DD cleanup criteria in the well.
The ADEC site status for ST068 is “Cleanup Complete with ICs.” A bioventing system was
operated at ST068 that had successfully remediated the vadose zone soil. GRO and benzene are
the only groundwater COC remaining at this site. Neither GRO nor benzene exceeded their
ST068 DD cleanup criteria in a sample collected from the in-source well 62WL-02R. The well
was installed in 2013 as a replacement for the damaged well 62WL-02. GRO concentrations had
exceeded the ST068 DD cleanup criteria in the former well.
Additional investigation to characterize the current nature and extent of soil and groundwater
contamination at ST068 will be proposed for ST068 in 2014 under the JBER PBR contract. No
changes to the annual monitoring are being proposed for this site. |
Louis Howard |
| 3/19/2014 |
Update or Other Action |
Scoping document received for ST068.
Objective:
Collect data to further characterize the site for evaluation using HRC to meet Air Force requirements for Response Complete.
(PER 18 AAC 75.345 (h) The department will require long-term monitoring if the department determines that monitoring is necessary to ensure protection of human health, safety, or welfare, or of the environment & if GW, surface water, soil, or sediment contains residual concentrations of a hazardous substance that exceed the applicable cleanup levels. If long-term monitoring is required under this subsection, a responsible person shall submit a plan & schedule for monitoring as part of the requirements for cleanup operations under 18 AAC 75.360. Unless otherwise approved by the department, a responsible person shall conduct monitoring quarterly for at least one year to establish the concentration trend. The department will evaluate the monitoring program yearly. If the monitoring indicates that the concentration trend
(1) is increasing, the department will require additional followup monitoring & assess the need for additional cleanup; or
(2) is stable or decreasing, & that hazardous substance migration is not occurring, the department will decrease or discontinue the monitoring frequency & locations, if the responsible person demonstrates that continued monitoring is not necessary to ensure protection of human health, safety, & welfare, & of the environment. The Air Force in this instance is interpreting RC to equal no GW monitoring requirements at ST068.)
Approach:
The Hydrocarbon Risk Calculator will be utilized to evaluate risk
ICs will be evaluated based on the level of risk as appropriate.
Characterize the aromatic & aliphatic equivalent carbon distribution of the GRO, DRO, & RRO
Define hydrogeologic & geotechnical properties using regional &/or site specific data
Compare site specific GW depth & flow direction data to regional flow & direction data
Identify soil type & terrain unit geotechnical data
Complicating Issues & Data Gaps
Extent of source area, downgradient & cross gradient --not yet documented
Need current analytical data for HRC parameters (DRO, GRO, RRO, BTEX, PAH, EPH, VPH)
Verify the zone of seasonal GW fluctuation (smear zone) thickness
SOIL
Define the horizontal & vertical extent of soil hydrocarbon contamination both above & below the water table using the step-out drilling approach
Sample soils in vadose zone & zone of seasonal water table fluctuation (smear zone):
Install three to four soil borings within the source area through the zone of seasonal GW fluctuation (smear zone)
Collect approximately 3 soil samples from each boring.
1 sample from vadose interval with highest PID results (if contaminated)
2 samples from the smear zone (one within & one below contamination)
Target Analytes: GRO, DRO, RRO, PAH, BTEX, EPH, & VPH
HRC Sampling:
A minimum of 10 soil samples from source zone to be analyzed for GRO, DRO, RRO, BTEX
A minimum of 3 soil samples from source zone to be analyzed for PAH, EPH & VPH (emphasis will be towards more heavily contaminated soils)
Two borings to be completed crossgradient of source area.
One boring to be completed downgradient of the source area (to be completed as a monitoring well)
Develop representative soil EPCs for the basic hydrocarbon analytes including GRO, DRO, RRO, BTEX, & PAHs
A step-out drilling approach will be used to further define the extent of contamination:
Advance a soil boring through the zone of seasonal GW fluctuation (smear zone) & screen soil boring samples as needed to verify contamination.
Step-out hydrologically downgradient at site specific distances & advance subsequent soil boring as needed to define the boundaries of the contaminated source area.
If necessary, a boring may be placed halfway between a boring pair where one is contaminated & the other is not contaminated.
The step-out distance will be determined by field conditions, but will be approximately 30% of the source length measured in the direction of GW flow. If a larger source area is indicated, then the boring step-out distance will increase accordingly.
Repeat the process to define the extent of contamination cross-gradient to the direction of GW flow.
GW
Further define the extent of GW contamination
Sample new downgradient well for GRO, DRO, RRO, & BTEX
Develop representative in source GW EPCs for the basic hydrocarbon analytes including GRO, DRO, RRO, BTEX, EPH, VPH, & PAHs
Sample in-source wells 64WL-01, 62WL-02R, & 62WL-03 for GRO, DRO, RRO, BTEX, PAH, EPH, & VPH
In-source well 62WL-05 was found damaged during the 2013 LTM effort; this well will be redrilled & sampled for the same suite
Input site characterization data into the HRC to evaluate risk.
Incorporate findings & conclusions in a Site Characterization & Risk Evaluation Report. |
Louis Howard |
| 8/20/2014 |
Update or Other Action |
Draft WP received for review and comment.
The objective at ST068 is to collect data to further characterize the site and to collect analytical data to evaluate risk via the HRC under ADEC Method Three. The results of the site
characterization and risk evaluation will be used in support of achieving RC.
Soil borings will be drilled to collect soil samples, which will be used to characterize the source area soil concentrations. Sufficient data will be collected to define the horizontal and vertical extents of source area contamination, both above and below the water table, using the step-out drilling approach described below. Approximately three borings will be advanced within the source zone; up to three of these borings will be completed as monitoring wells, one near
Building 11575 and one near Building 10480. Up to four borings will be completed crossgradient of the source area. One boring will be completed downgradient of the source area and completed as the downgradient monitoring well.
If the initial downgradient boring is contaminated, it will be considered one of the required in-source borings. Another boring will be drilled further downgradient and completed as a monitoring well, as long as the boring is clean. Vadose zone soil will be screened via PID; analytical soil samples will be collected from the vadose zone if PID readings indicate contamination. One analytical soil sample per boring will be collected from both the zone of seasonal water table fluctuation (smear zone) and from below the vertical extent of contamination.
The investigation will target the collection of a minimum of 10 soil samples from the source area
for GRO, DRO, residual-range organics (RRO) and BTEX analysis, and a minimum of three samples for petroleum-related volatile organic compounds (VOCs), polycyclic aromatic hydrocarbons (PAHs), extractable petroleum hydrocarbons (EPH) and volatile petroleum hydrocarbons (VPH) analysis.
The source area samples with the highest PID readings will be collected and analyzed for PAHs, EPH and VPH. Samples collected from these more heavily contaminated soils will tend to provide conservative results. Data will be used to develop representative soil exposure point concentrations for the basic hydrocarbon analytes including GRO, DRO, RRO, BTEX, and PAHs. A step-out drilling approach will be used to define the extent of contamination. The initial soil boring will be advanced through the zone of seasonal groundwater fluctuation (smear zone) and soil samples will be screened to verify contamination.
In order to verify and further define the extent of contamination, a monitoring well will be
advanced downgradient of the known plume. Depending on the field investigation, at least one, and up to three new in-source monitoring wells will be installed; one each near Building 11575 and Building 10480, and one to potentially replace Well 62WL-05, which may be damaged beyond repair.
Wells will be sampled for the following analytical parameters:
• Upgradient Well 62WL-01: GRO, DRO,/RRO, and BTEX
• Up to three new in-source wells: GRO, DRO, RRO, BTEX, PAHs, VPH, EPH, and vapor intrusion (VI) parameters (VOCs)
• Current in-source Wells 64WL-01, 62WL-02R, 62WL-03, and 62WL-05: GRO, DRO, RRO, BTEX, PAHs, VPH, EPH, and VI parameters (VOCs)
Data will be used to develop representative in-source groundwater exposure point concentrations
for the basic hydrocarbon analytes including GRO, DRO, RRO, BTEX, EPH, VPH and PAHs. |
Louis Howard |
| 8/28/2014 |
Update or Other Action |
Staff provided comments on the draft SC work plan.
ES-2 Site-Specific Background
If the requirement for analysis under 18 AAC 75 requires lead, ethylene dibromide (EDB) & 1,2-Dichloroethane (1,2-DCA) or other COCs which were not analyzed for previously, then these COCs would need to be added as part of the investigation prior to the updated or new decision document. Also the most current cleanup levels in 18 AAC 75 would need to be reflected in any updated or new decision document for ST068.
ES-4 Borings & Soil Sampling
Unless JBER has data to support these COCs be excluded from this investigation, ADEC will require analysis of soil that have the highest PID readings (minimum of one soil sample each from the two soil borings along the A to A’ axis on Figure 2) for EDB , 1,2-DCA & lead.
The text states: “Wells will be sampled for the following analytical parameters:
• Upgradient Well 62WL-01: GRO, DRO,/RRO, & BTEX
• Up to three new in-source wells: GRO, DRO, RRO, BTEX, PAHs, VPH, EPH, & vapor intrusion (VI) parameters (VOCs)
• Current in-source Wells 64WL-01, 62WL-02R, 62WL-03, & 62WL-05: GRO, DRO, RRO, BTEX, PAHs, VPH, EPH, & VI parameters (VOCs)”
ADEC requests all monitoring wells sampled as part of this investigation include analysis for EDB, 1,2-DCA & lead. If these sample results are below Table C criteria, then they no longer need be considered a COC in GW.
WS #17 Sampling Design & Rationale
Page 17-1
The text states: “If the site conditions meet the ADEC risk standard, a determination will be made that ST068 meets AF RC with Institutional Controls (ICs).”
The site currently is assigned a “cleanup complete – institutional controls” status which ADEC views as AF Response complete with institutional controls (ICs).
Page 17-2
The text states: “On a site-specific basis, exposure point concentrations for additional target analytes may be required (for example, lead & EDB may be required at gasoline release sites).”
Lead, EDB, 1,2-DCA are also required for gasoline, aviation gasoline (aka AVGAS) & all waste oil, used oil, or unknown product type releases.
Site-Specific Sampling Plan
Borings & Soil Sampling
Page 17-3
The text states: “A minimum of one, but potentially up to three samples will be collected from a boring location & submitted for laboratory analysis of the primary sampling suite: GRO, DRO, RRO, & BTEX.”
Page 17-4
The text states: “The investigation of the source area will target the collection of a minimum of 10 soil samples from the source area for GRO, DRO, RRO, & BTEX analysis…”
See Comment #2 above regarding EDB, 1,2-DCA & lead analysis for soil at ST068 due to AVGAS being a product that is associated with ST068.
GW Sampling
Page 17-5
The text states: “Analytical parameters will be as follows:
• Upgradient Well 62WL-01: GRO, DRO, RRO, & BTEX
• Up to three new in-source wells: GRO, DRO, RRO, BTEX, PAHs, VPH, EPH, & VI parameters (VOCs)
• Current in-source Wells 64WL-01, 62WL-02R, 62WL-03, & 62WL-05: GRO, DRO, RRO, BTEX, PAHs, VPH, EPH, & VI parameters (VOCs)”
See Comment #2 above regarding EDB, 1,2-DCA & lead analysis for GW at ST068.
Soil Gas Sampling
Page 17-6
The text states: “If the HRC indicates unacceptable VI risk based on GW sample results, then soil gas sampling will be performed.”
Please reference the 2014 Basewide UFP-QAPP which contains the latest version of SOPs (5a-5f) for Soil gas SOP-05 Soil Gas Sampling.
For example, the text could state: “If the HRC indicates unacceptable VI risk based on GW sample results, then soil gas sampling will be performed in accordance with the SOP-05 Soil Gas Sampling in the approved JBER Basewide UFP-QAPP (USAF, 2014).”
The text states: “If soil gas sampling indicates VI risk, then indoor air sampling will be considered.”
Please note that if the indoor air concentrations of any COC exceeds one-tenth of the indoor air target level, ADEC recommends at least two rounds of sampling to investigate variability & seasonal trends before deciding if further work is necessary (ADEC Vapor Intrusion Guidance for Contaminated Sites October 2012).
Additionally, state that ADEC’s Building Inventory & Indoor Air Sampling Questionnaire will be completed for each building under investigation combined with a building walk-through. |
Louis Howard |
| 9/25/2014 |
Document, Report, or Work plan Review - other |
ADEC has reviewed the Air Force's responses to ADEC's comments and finds the responses satisfactory. The work plan may be finalized. |
Louis Howard |
| 9/25/2014 |
Meeting or Teleconference Held |
Response
NOTE: In the Comment Resolution Meeting held 15 Sept 2014, a change in approach toward achieving Air Force “Response Complete” status was discussed.
ADEC COMMENT: Site-Specific Background
The text states: “The Decision Document criteria will continue to be the legal cleanup criteria until the Decision Document is formally updated in agreement with the ADEC to the current 18 AAC 75 Table C criteria.”
If the requirement for analysis under 18 AAC 75 requires lead, ethylene dibromide (EDB) and 1,2-Dichloroethane (1,2-DCA) or other COCs which were not analyzed for previously, then these COCs would need to be added as part of the investigation prior to the updated or new decision document. Also the most current cleanup levels in 18 AAC 75 would need to be reflected in any updated or new decision document for ST068.
AF RESPONSE: Since the site already has a “Cleanup Complete-ICs” status and “Response Complete” requires a “Cleanup Complete-ICs” status with no ongoing monitoring, the revised approach involves the preparation of a trend analysis to determine groundwater plume stability. If the plume can be demonstrated to be stable to the ADEC, then periodic groundwater monitoring can be terminated. A report documenting the trend analysis will be prepared for submittal to the ADEC.
The following Responses to Comments have been prepared in the event that the Decision Decision for the site is ever opened for modification.
Concur: If the Decision Document is opened for future characterization of the site, EDB and 1,2-DCA will be added to the analytical suite as part of the field investigation for this site.
Any updated or new decision document would reflect the current 18 AAC 75 cleanup levels.
ADEC COMMENT: Sampling Design and Rationale
Page 17-1
The text states: “If the site conditions meet the ADEC risk standard, a determination will be made that ST068 meets AF RC with Institutional Controls (ICs).”
The site currently is assigned a “cleanup complete – institutional controls” status which ADEC views as AF Response complete with institutional controls (ICs).
AF RESPONSE: Understood that the site is designated “cleanup complete – institutional controls”. The AF “Response Complete” designation requires the elimination of periodic groundwater monitoring. A dissolved phase trend analysis will be conducted. If the trend analysis shows a stable or decreasing trend and that hazardous substance migration is not occurring, then cessation of long-term monitoring will be requested.
|
Louis Howard |
| 12/24/2014 |
Update or Other Action |
Draft GW Trend Analysis report received. The ST068 DD & the ADEC Contaminated Site Database identify the ST068 site status as “Cleanup Complete with Institutional Controls” with ongoing GW monitoring. The section of the contaminated site regulations addressing the need for long-term monitoring (18 AAC 75.345[h][2]) indicates that monitoring may be eliminated if it can be shown that the GW has a stable or decreasing concentration trend, & that the monitoring is not necessary to ensure the protection of human health or the environment.
It appears that the sampling &/or laboratory method used in September of 1995 & 1996 & in 1997 provided anomalously low GRO results. The interpretation that the September of 1995 & 1996 & 1997 GRO results are anomalously low is corroborated by the fact that the BTEX results in the same well were more consistent & higher than the GRO detection limit. A better understanding of the recent GRO concentration trend in 62WL-05 may be derived from using the GRO data collected between 1999 & 2012 (when low-flow sampling techniques & the AK101 test method were consistently used). Figure 4 shows a “statistically significant evidence of a decreasing trend” at the 95% confidence level, & the time-series graph shows a clear decreasing trend.
The benzene data from 62WL-05 presented in Figure 5 show a “statistically significant evidence of a decreasing trend” at the 95% confidence level, & the time-series graph shows a clear, consistent decreasing trend.
Monitoring well 62WL-05 is in the downgradient portion of the ST068 source area, & consequently, GW samples from this well are interpreted to be representative of the dissolved phase concentrations that emanate from the NAPL-contaminated source area & cause the downgradient dissolved phase plume. Monitoring well 62WL-05 currently has the highest GRO & benzene concentrations of the wells monitored at the ST068 site.
The biodegradation of the dissolved hydrocarbon emanating from the ST068 source area is documented by the low &/or non-detect results of the monitoring conducted in monitoring well 62WL-06, which is less than 400 feet downgradient of the ST068 source.
Monitoring well 62WL-02 is in the upgradient third of the ST068 source area, & downgradient of the area treated by the bioventing system. The 1994 to 2013 GRO data presented in Figure 6 show “insufficient evidence to identify a significant trend” at the 95% confidence level. The Mann-Kendall analysis was rerun at the 90% confidence level, & there was “statistically significant evidence of a decreasing trend” at the 90% confidence level.
The benzene data from 62WL-02 presented in Figure 7 show a “statistically significant evidence of a decreasing trend” at the 95% confidence level. The time-series graph shows a clear, consistent, decreasing trend, & that benzene concentrations have been below cleanup levels for the last two monitoring events.
GW monitoring is no longer needed to protect human health at ST068, because there is an administrative LUC prohibiting the use of GW from the shallow aquifer for any purpose (e.g., drinking water, irrigation, fire control, dust control, etc.). The LUC will remain in effect until the GW cleanup levels have been met. Future monitoring would be performed at USAF discretion.
GW monitoring is no longer needed to protect the environment downgradient of ST068, because the dissolved hydrocarbon biodegrades relatively close to the NAPL-contaminated soil source area & far upgradient of Ship Creek (which ultimately receives the GW flowing through the ST068 site). The biodegradation of the dissolved hydrocarbon emanating from the ST068 source area is documented by the low &/or non-detect results of the GW monitoring conducted in 62WL-06. |
Louis Howard |
| 1/7/2015 |
Document, Report, or Work plan Review - other |
Staff provided review comments on the GW Trend Analysis Report (draft).
Site-Specific Background
Page 1-2
Please add text to this section stating that 62WL-02 is not the current well being monitored. The replacement well currently sampled is now 62WL-02R. In 2013, a site inspection identified that Well 62WL-02 was found to be damaged, likely by a lawn mower or other maintenance equipment. The damaged well was properly abandoned & a new replacement well, 62WL-02R, was installed, developed, & sampled for analyses of GRO & benzene. Neither GRO nor benzene results exceeded the GW criteria in Well 62WL-02R.
Page 1-3
Unless there is data to the contrary, it appears lead, ethylene dibromide (EDB), 1,2-Dichloroethane (1,2-DCA) & 1,2-dichloropropane (1,2-DCP) were not analyzed for previously at ST068. Polynuclear aromatic hydrocarbons (PAHs) would also need to be included if not analyzed before at ST068 & demonstrated to be below applicable cleanup levels.
These COCs would need to be added as part of the any future GW monitoring requirements at ST068 in addition to the updated or new decision document. The requirement for lead & lead scavengers are based on the original sources for ST068 which includes aviation gasoline.
Site ST068 is associated with Tank Farm 3, which has five underground storage tanks (USTs). These USTs include three 50,000-gallon jet propellant fuel type 4 (JP-4) USTs, one 25,000-gallon aviation gas UST [Tank 42 (STMP 107)], & one 12,000-gallon diesel fuel UST. Aviation gasoline is known to contain lead & lead scavengers.
Also the most current cleanup levels in 18 AAC 75 for GRO, DRO, BTEX, would need to be reflected in any updated or new decision document for ST068
Monitoring Well 62WL-02 Results
Text needs to be added explaining to the reader why the GRO ND data for 62WL-02 from: 1995-2 ND (170 µg/L) & 1998-2 ND (10.6 µg/L) GRO data was not included in the trend analysis on Figure 6 while the benzene ND data for 2001-1 & 2001-2 (0.11 µg/L for both events) was included & used on Figure 7. Also please note 62WL02-02 benzene trend analysis is valid for 1994 – 2012. In 2013 the well was found to be damaged & replaced by 62WL-02R. The table needs to reflect this change in wells in Figure 7 as is done on Figure 6 to be consistent.
ADEC typically recommends that the 95% confidence level be used when determining trends with Mann-Kendall. Mann-Kendall trends are identified as “decreasing” or “increasing” if the test resulted in a significance of =95%; otherwise, trends were classified as “no trend.”
Conclusions
ADEC concurs with the conclusions to discontinue monitoring of GW at ST068, but the status of the site (ST068) shall remain indefinitely as: “cleanup complete with institutional controls” until the concentration of contamination in the GW reaches cleanup levels that allow for unlimited use & unrestricted exposure . The implementation of LUCs would continue until GW & smear zone soil contamination is no longer a threat to human health & the environment (i.e., one analytical GW sampling round shows contaminant levels below GW cleanup levels). This would then be verified by two years of consecutive GW sampling events where analytical results in all of the ST68 monitoring wells show that the COCs are less than the applicable GW cleanup levels (2007 ST068 Decision Document Page 5-2).
If the Air Force determines that it cannot meet specific land use control requirements, it is understood by all parties that the remedy may be reconsidered & that additional measures may be required to ensure the protection of human health, welfare, safety &/or the environment. A LUC review would be required no less than every five years to ensure the controls that are in place are effective & continue to protect human health, welfare, safety & the environment.
Additional GW monitoring of the GW at the site will be required if the Air Force wishes to remove the institutional controls at the site for DRO, GRO, BTEX, PAHs, lead, & lead scavengers (EDB, 1,2-DCA & 1,2-DCP).
Recommendations
ADEC will require additional analytes for existing GW monitoring wells as well as a new monitoring well (near or at 62WL-07’s former location) for ST068 should the Air Force decide to pursue a cleanup complete determination from ADEC. These analytes would include lead, PAHs & lead scavengers in addition to the DRO, GRO, BTEX analytes. |
Louis Howard |
| 2/19/2015 |
Document, Report, or Work plan Review - other |
Staff provided two minor comments on reference updates and approved redline version of the Groundwater Trend Analysis for ST068 as a final version. |
Louis Howard |
| 5/19/2015 |
Document, Report, or Work plan Review - other |
Staff provided comments on the draft annual groundwater monitoring report for State Sites which included this site. Main comments were made requesting analysis of groundwater include lead, ethylene dibromide, 1,2-dichlroethane and 1,2-dichloropane and polynuclear aromatic hydrocarbons if they were not analyzed before by the Air Force during prior monitoring events for Tank 42 which contained aviation gasoline. This would be required if the Air Force wished to revise the decision document and change the status of the site from cleanup complete with institutional controls to cleanup complete. Finally, staff stated that groundwater monitoring may wells will need to be maintained in case they are needed for future monitoring of ST068 constituents in the future, compliance monitoring program needs, future monitoring for PFCs or 1,4-dioxane as downgradient sentry well or upgradient wells as part of a routine monitoring program requirement to track 1,4-Dioxane or PFCs in groundwater. |
Louis Howard |
| 11/15/2017 |
Update or Other Action |
Draft 2016 Annual Report Monitoring of State-Regulated Sites received. There was some ground disturbance at the center of the site near the intersection of Mundy and Sijan Ave.; it looked like new piping was buried below the ground surface. Construction and paving activities were observed northeast of the site, in the flightline area.
Wells appear to be secure and in good condition. The condition of well 62WL-05 is good, however during repaving of the parking lot an outer casing was installed around the original outer well casing. The lid is labeled “cleanout” and the inner metal lid for well casing is slightly cemented in and unopenable. The excavation was for waterline repair and was outside of any areas of past contamination.
See site file for additional information. |
Louis Howard |
| 11/30/2017 |
Update or Other Action |
Draft VI report received for review and comment. The BTEX compounds are considered to be the most volatile, and therefore more mobile, of the aromatic hydrocarbons. Naphthalene has a relatively low volatility and is likely to partition to soil or sediment, thereby limiting its mobility in the environment. Based on these characteristics, naphthalene may not be an appropriate indicator for determining if the VI pathway is complete (as compared to the other COIs).
The Building 11568 aircraft fuel pumping station (see Appendix C, Photograph C.23), which is
located approximately 175 feet west of the southwestern corner of Building 11551 (see Figure
5.12), could be a potential source for ambient air petroleum impacts. Specific characteristics of Building 11568 operations, including the venting of petroleum vapors, are not known.
Regardless of the uncertainties associated with the relationship between indoor and outdoor air
results, the presence of multiple COIs in indoor air and soil gas suggest the presence of a
potentially complete VI pathway at Building 11551.
See site file for additional information. |
Louis Howard |
| 7/23/2018 |
Document, Report, or Work plan Review - other |
Staff responded with letter to a request for the Air Force on confirming cleanup complete with ICs as stated in an ADEC letter of January 7, 2015 stating same. DRO, GRO, BTEX, PAHs, lead and lead scavenger sampling of groundwater will be required to meet cleanup levels for a minimum of two consecutive rounds prior to ceasing groundwster monitoring.
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 |
| 5/18/2024 |
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 |
| 2/12/2025 |
Document, Report, or Work plan Review - other |
DEC submitted comments regarding the Non-UST Closure Report Repair Fuel Farm #4 Project FXSB 17-4720, dated January 2025. The report describes the field screening and soil sampling activities associated with the demolition and construction activities at the Fuel Farm #4 site located on Joint Base Elmendorf- Richardson (JBER), Anchorage, Alaska. Excavation activities Contamination in soil did not exceed DEC’s most stringent cleanup levels and the report recommends the closure of the Fuel Farm #4 site. |
Ginna Quesada |
| 2/24/2025 |
Document, Report, or Work plan Review - other |
DEC approved of the Non-UST Closure Report Repair Fuel Farm #4 Project FXSB 17-4720, dated January 2025, revised February 2025.The report describes the field screening and soil sampling activities associated with the demolition and construction activities at the Fuel Farm #4 site located on Joint Base Elmendorf- Richardson (JBER), Anchorage, Alaska. Excavation activities Contamination in soil did not exceed DEC’s most stringent cleanup levels and the report recommends the closure of the Fuel Farm #4 site. |
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 |
