| Action Date |
Action |
Description |
DEC Staff |
| 8/31/1983 |
Update or Other Action |
Engineering Science reviewed records on file at the Bioenvironmental Engineering Office and interviewed shop personnel to determine the types of hazardous materials, waste quantities and disposal methods. Following these interviews, the drain outfalls were identified as potential sources of environmental contamination because of the nature of compounds thought to have been discharged down floor drains in the building.
During the time the building was used for helicopter maintenance, the facility produced the following amounts of waste material per month: 15 gallons of engine oil, 5 gallons of hydraulic fluids, 5 gallons of JP-4, 55 gallons of *PD680 (stoddard solvent). Between 1970 and 1980, some of the material was removed from the building and stored in an underground storage tank adjacent to the old Power Plant (bldg. 11-433), and some was removed by an off-base contractor. The rest of the material was washed into the floor drains. Since the early 1980s, waste materials were disposed of through the DPDO (Now DRMO).
*NOTE: Each item the Govt. orders must have an N.S.N, a National Stock Number, unless the Agency gets special permission to local purchase the item. Each N.S.N. item goes out for bid and has an
associated minimum specification. The specification for PD680, aka. Stoddard Solvent, back in the 1980's and before was for a petroleum based degreaser with a specified flashpoint. No
requirement for non-halogenated existed. Besides that, because Alaska was so far from venders that supplied the Govt., many federal agencies in Alaska purchased solvents locally. There were no qualifications on those solvents and most often halogenated solvents worked with less effort than pure petroleum distillates, so they were preferred.
NSNs ordered through the PD680 specs had some batches with TCE, Methylene chloride, etc; it depended on who the supplier to the Govt.was at the time. So as a result between 1980 and 1983,
some PD680 batches were in fact halogenated. For historical releases it pays to be aware that chlorinated solvents may be associated with releases from PD680 or Stoddard Solvent. |
Louis Howard |
| 8/2/1988 |
Update or Other Action |
Operable Units' source areas that correspond to RCRA SWMUs from the RCRA RFA. SD26 IS-3 Bldg. 43-550 Floor Drain. This site was used for helicopter maintenance, -55 gals/month of PD-680* was used with some going down drain to dry well.
*NOTE TO FILE: PD-680 Each item the Govt. orders must have an N.S.N, a National Stock Number, unless the Agency gets special permission to local purchase the item. Each N.S.N. item goes out for bid and has an associated minimum specification. The specification for PD-680, aka. Stoddard Solvent, back in the 1980's and before it was for a petroleum based degreaser with a specified flashpoint. No requirement for non-halogenated existed. Besides that, because Alaska was so far from vendors that supplied the Govt., many federal agencies in Alaska purchased solvents locally. There were no qualifications on those solvents and most often halogenated solvents worked with less effort than pure petroleum distillates, so they were preferred.
NSNs ordered through the PD-680 specs had some batches with TCE, Methylene chloride, etc; it depended on who the supplier to the Govt.was at the time. So as a result between 1980 and 1983, some PD-680 batches were in fact halogenated. For historical releases it pays to be suspicious of drums that say PD-680 or Stoddard Solvent. |
Louis Howard |
| 3/18/1989 |
Update or Other Action |
Dept. of Air Force letter to Sue Curtin Black & Veatch.
Per your telephone request with Capt Godsave, we submit the following
information:
1. Storm sewer system maps for SP15, SP5/5A, SP7/10, IS-1: Attached.
2. Jet Fuel Supplier: Jet fuel is supplied per one year contracts. Presently, the majority of fuel is supplied by ARCO. Their contact person is Ms Candy Stallings, 213-486-2824. Other suppliers are Tesoro (Contact - Mr Raymond Measles at 907-561-5521), Chevron (415-944-6250), and Mapco (contact - Ms Bonnie Garner at 907-276-4100).
3. Buildings 42-400, 42-425, 43-550, 42-300, 43-410, 43-450, 32-060 floor drains: Originally, minor spillage and products operations in these facilities were washed into floor drains to dry wells. Present conditions are below. Since as-builts clear, this information may not be totally correct. 21-900, and from cleaning and from there are old and not
a. IS-1, Building 42-400: Floor drains run into two oil-water separators.
b. IS-2, Building 42-425: Sanitary sewer runs along side of building, unclear whether floor drains run into it or not.
c. IS-3, Building 43-550: Sanitary sewer runs along side of building, do not know whether floor drains run into it or not.
d. IS-4, Building 42-300: Floor drains run into an oil-water separator and then into the storm drain on the east and west side of the building.
e. IS-5, Building 43-410: Floor drains are connected to septic tank and leach fields at south side of building.
f. IS-6, Building 43-450: Floor drains probably go to the septic tank and leach pits east of the building and across the railroad track.
g. IS-7, Building 21-900: The floor drains run through sumps to remove sand and grit and dump right into the storm drain on the north side of the building. The floor drains for the mechanical room run out the south side of the building and into a seepage pit. There is also a catch basin on the south side of the building that runs into a seepage pit.
h. IS-8, Building 32-060: Although sanitary sewers run near the building, it appears that floor drains go directly to dry wells.
4. How close can wells be put to the runway? If top cover of wells are flush with the ground surface, there should not be a problem. If above ground surface and within 1000 feet of the runway, the well will require a waiver. If within 500 feet of the runway, well may also be required to be frangible.
5. If well is near the runway, can piping go underground beneath a taxiway to a treatment facility? That should not be a problem if taxiway is tunneled under.
6. What is the frost depth for Elmendorf AFB? The Building Code says 42 inches.
7. Does DRMO recycle fuel? DRMO does have a contract to recycle fuel.
8. At Site D-16, can soil at the site be used for grading? If soil is within acceptable levels for contaminants, yes. However, trees should be left as much as feasible.
9. How much would a contractor be required to pay the government for electricity? The government normally supplies contractors reasonable amounts of electricity at no cost. The government also requests that contractors, in this case, practice conservation.
Signed
Thomas Ritz Major, USAF
Acting Chief, Engineering & Environmental Planning Branch. |
Jennifer Roberts |
| 12/29/1989 |
Update or Other Action |
ADEC letter to Everett L. Mabry Colonel, Base Civil Engineer, HQ 21st Combat Support Group (AAC) RE: RI/FS Stage 4 Second Draft Work Plan Elmendorf Air Force Base, October 1989.
SITE IS-3
The Department requests that the source of the pesticide alpha-BHC be determined.
Paragraph 5.2.2.9 does not clearly state the drainage status of
the floordrains. The Department requests that the drainage status
of the floordrains be determined. If the floordrains are currently
hooked into dry wells, we request that the floordrains be properly
hooked into an oil/water separator and the discharge water be
properly disposed of under Alaska Water Quality Regulations. |
Ron Klein |
| 12/30/1989 |
Site Added to Database |
Solvent contamination. |
Louis Howard |
| 9/15/1990 |
Update or Other Action |
Black and Veatch investigation placed a boring, collected soil samples at 15 feet and 45 feet, and finished the boring as a monitoring well (IS3-01). In this area groundwater is generally at 40 feet. TPH was detected at 1,300 ug/L in a groundwater sample and 2 pesticides, alpha BHC and delta BHC, were detected at 26 ug/l and 1.7 ug/l respectively. Also, dissolved manganese exceeded the secondary drinking water standards. Use of geophysical techniques, B&V concluded that dry wells existed under the east and west ends of the building. Location of the dry wells in relation to the location of well IS3-01 indicated that the chemicals detected in the monitoring well may not adequately represent environmental contamination from the dry wells. |
Jennifer Roberts |
| 11/12/1991 |
Enforcement Agreement or Order |
Federal Facility Agreement under Comprehensive Environmental Response, Compensation, and Liability Act (CERCLA) signed for docket # 1089-07-19-120. The agreement ensures that the environmental impacts associated with past and present activities at the Base are thoroughly investigated and appropriate removal and/or remedial action(s) taken as necessary to protect human health and the environment. Elmendorf Federal Facility Agreement signed.
The general purposes of this Agreement are to: (a) Ensure that the environmental impact associated with past and present activities at the Site are thoroughly investigated and appropriate removal and/or remedial action(s) taken as necessary to protect the public health, welfare, and the environment.(b) Establish a procedural framework and schedule for developing, implementing, and monitoring appropriate response actions at the Site in accordance with CERCLA, the NCP, Superfund guidance and policy, RCRA, RCRA guidance and policy, and applicable state law.
The FFA divided the CERCLA study source areas at Elmendorf AFB into the following seven operable unites (OUs), on the basis of geographic proximity and similar source characteristics or contaminants:
- OU1 Landfills (LF05, LF07, LF13, LF59, OT56)
- OU2 Tank Spill Sites (ST20, ST41, including the ST41 Sludge Disposal Area)
- OU3 Central Containment Area (SD16, SD31, SD52, SS21)
- OU4 Northern Containment Area (SD24, SD25, SD28, SD29, FT23, SSl0)
- OU5 Southern Containment Area (ST37)
- OU6 Surface Disposal Sites (LF02, LF03, LF04, SD15, SD73, WP14)
- OU7 Limited Field Investigation (SS19)
Proposed listing on NPL was 07/14/1989 and Final listing on NPL was on 08/30/1990.
SD26 (formerly IS-3) Bldg. 43-550 Floor Drain. This site was used for helicopter maintenance contains a wash rack, 55 gallons per month of PD-680 were used with some going down drain to dry well.
See site file for additional information. |
Jennifer Roberts |
| 11/12/1991 |
Update or Other Action |
Jennifer Roberts Federal Facility Coordinator sent letter to Joe Williamson and Rich Howard pursuant to Section 9.1 of the Elmendorf Air Force Base Federal Facility Agreement (FFA). ADEC designates Jennifer Roberts as the Project Manager and Ron Klein as the Alternate Project Manager for all activities covered under the FFA. |
Louis Howard |
| 12/30/1991 |
Update or Other Action |
EPA sent letter to AF Rich Howard and Joe Williamson. The notification will serve as an addendum to the previous letter of November 4, 1991 which designates the USEPA project managers pursuant to Section 9.1 of the Elmendorf Air Force Base (EAFB) Federal Facilities Agreement (FFA). Marcia Combes will serve a lead remedial project manager (RPM) for Base-wide activities, as well as Operable Units (OUs) 2, 3, 5, 6, 7. Michele Poirier-McNeill will serve as lead RPM for OUs 1 and 4. In addition, both RPMs will serve as an alternative RPM on OUs for which they are not the lead. For communication and correspondence purposes, the lead RPM should be the point of contact, and the alternate should be copied. |
Jennifer Roberts |
| 5/21/1992 |
Meeting or Teleconference Held |
During a May 21, 1992 meeting, the remedial project managers for the USAF, USEPA and ADEC evaluated the geophysical data collected during the LFI and historical data. Due to the location of the geophysical anomaly and the estimated direction of groundwater flow, the RPMs determined that the anomaly was not the source of the previously detected groundwater contamination. Therefore no sampling was conducted at SD26. A more thorough discussion of the GPR survey and associated findings is provided in Appendix A to the Final OU4 LFI Report CH2MHILL 1992. |
Jennifer Roberts |
| 9/16/1992 |
Update or Other Action |
USAF letter to Jennifer Roberts regarding "Revisions to Elmendorf AFB Federal Facility Agreement (FFA) Scope of Work for Operable Units (OU) 4 and 7." As a result of the 1992 field investigation, the USAF requests to move FT23 from OU7 to OU4. Based on the results of the Limited Field Investigation (LFI) it appears FT23 may be the source of contamination observed in past investigations at SD24, SD25, SD26, and SD27.
Delete the requirement of an interim remedial action (IRA) at OU4. Based on the LFI, the remedial project managers identified the dry wells at SD24, SD28, and SD31 as potential IRAs. However, further review of the results of the LFI, indicate only the sludge at the bottom of the dry well at these sources were sampled and no soil samples were obtained. At this time there is no evidence of soil contamination in the immediate vicinity of the dry wells. Without additional investigation of these wells, it does not appear an IRA is warranted. Instead of an IRA, we will pursue funding to remove the sludge in each dry well. ADEC project manager Jennifer Roberts signed document to show its concurrence. |
Jennifer Roberts |
| 10/15/1992 |
Update or Other Action |
USAF 1992 LFI conducted at SD26 was used to assess the final disposition of the outfall and to recommend a no further action (NFA) or that a remedial investigation/feasibility study (RI/FS) be conducted. As a result of the geophysical survey and the research of other potential contaminant sources, SD26 is not a source of the groundwater contamination observed in monitoring well IS3-01.
NOTE TO FILE: SD26 and SD27, while recommended for NFA, are still located within the boundary of OU 4. The groundwater and soil contamination [present at SD26 and SD27] associated with these two facilities were considered as part of the overall OU 4 contamination. (OU4 2.2 Regulatory and Enforcement History Page 2-4 September 1995)
Although the direction of groundwater flow is not completely defined in this area, the location
of the geophysical anomaly at SD26 is not hydraulically upgradient of well IS3-01. The
results of the research conducted to identify other potential sources of contamination near
SD26 indicated that potential upgradient sources existed. These sources include reported fuel
spills; petroleum, oil, and lubricants (POL) lines; underground storage tanks; and Source FT23,
the fire training area.
Some of these sources are contributing to the groundwater contamination detected in earlier investigations at monitoring well IS3-01. The fire training area is known to be contaminated with a variety of contaminants, including fuels, chlorinated solvents, and pesticides. In addition, information obtained on past uses of Building 43-550 and nearby buildings indicated that no pesticides had been used in that area. The pesticides found in a groundwater sample from a previous investigation are therefore not likely to have been caused by the use of the drains and outfalls at SD26.
The fire training area is known to be contaminated with a variety of contaminants, including fuels, chlorinated solvents and pesticides. For this reason, the fire training area, Source FT23, was added to OU4 for purposes of future investigations under CERCLA. The extent of groundwater contamination from the fire training area and in the vicinity of SD26 will be evaluated during the OU4 remedial investigation scheduled for 1993. |
Jennifer Roberts |
| 12/4/1992 |
Document, Report, or Work plan Review - other |
Letter sent to USAF regarding the Draft Operable Unit (OU) 4 ARARs. Citations to the National Contingency Plan (NCP) need to be included for all legal assertions in this section and throughout the document. For example, in section 2.2 the draft makes a statement without reference to the Code of Federal Regulations: " The NCP states that cleanup level of zero is not appropriate for Superfund-type cleanups because:
(1) CERCLA does not require the complete elimination of risk; and
(2) it is impossible to detect whether 'true' zero has actually been attained." The State of Alaska Water Quality Standards contained in 18 AAC 70 apply to groundwater as well as surface water. See 18 AAC 70.110.(46): "'water' means lakes, bays, sounds, ponds, impounding reservoirs, springs, wells, rivers, streams, creeks, estuaries, marshes, inlets, straits, passages, canals, the Pacific Ocean, Gulf of AK, Bering Sea, and Arctic Ocean, in the state's territorial limits AND all other bodies of surface or underground water that are wholly or partially under state jurisdiction." See also AS 46.09.900(35).
The state's water quality standards are therefore applicable to groundwater. As promulgated regulations, Alaska's water quality criteria are ARARs. See United States v. Akzo Coatings of America, 946 F.2d 1409 (6th Cir. 1991). To the extent, state water quality regulations adopt USEPA's water quality criteria are also ARARs and not "potentially TBC standard." See e.g. 18 AAC 70.020(b) (Toxics and other Deleterious organic and inorganic substances). To correct this confusion between state and federal requirements in this area, a new section entitled "Alaska State Water Quality Standards" is suggested. |
Jennifer Roberts |
| 3/26/1993 |
Update or Other Action |
DOD and ADEC joint Technical Memorandum of understanding signed concerning the Base-wide Groundwater (GW) signed by: ADEC Jennifer Roberts RPM and USAF Joseph Williamson Chief Environmental Programs and Restoration. Due to the base-wide GW study and the FY92 field work that occurred at Operable Units (OUs) 1, 2, and 5 it appears a large portion of the GW flows into OU5 (Attachment 1-Contour Map). Based on this fact, Elmendorf (EAFB) will move all upgradient GW into the OU5 Feasibility Study, Proposed Plan and Record of Decision (ROD).
This means addressing all GW from upgradient sources (CERCLA (ST20, OUs 3 and 4) and OUs 1 and portions of OU2) and SERA) at OU5 instead of at each individual source area (see Attachment 2-Area Map). Sites with 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 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.). |
Jennifer Roberts |
| 5/7/1993 |
Conditional Closure Approved |
Historical records available for SD26 indicate that, from 1970 until the early 1980s, waste engine oil, hydraulic fluids, JP-4, and PD680 were produced at the facility. Some of these
waste materials were washed into floor drains that were reportedly connected to dry wells. According to base personnel, the floor drains and latrines are currently connected to the
sanitary sewer, and building personnel are not aware of any dry wells, septic tanks, or leach fields.
Concentrations of chemicals detected in soil samples collected from SD26 during the previous investigation by Black and Veatch were compared to RBCs and applicable or relevant and appropriate requirements (ARARs found in the Final OU4 LFI report CH2MHILL 1992). Those results showed that organic compounds were not detected in the soils and the concentrations of metals did not exceed background soil data. As a result of the geophysical survey and the research of other potential contaminant sources, SD26 is not a source of the groundwater contamination observed in monitoring well IS3-01. The recommended action for the floor drains and outfall structure investigated at SD26 is no further action (NFA).
Of the other contaminant source areas near SD26, only POL lines and the fire training area lie hydraulically upgradient of monitoring well IS3-01 at SD26. The current condition of the POL lines upgradient of SD26 is unknown. Based on preliminary groundwater directions, it appears that the fire training area may be the primary source of groundwater contamination. For this reason, Source FT23 was added to the OU4 for purposes of future investigations under CERCLA. The extent of groundwater contamination from the fire training area FT23 and in the vicinity of SD26 will be evaluated during the OU4 RI scheduled for 1993.
USAF Determination of No Further Action for purposes of investigation or study is justified for source SD26 Building 43-550 dated April 1993. Document was signed by USAF Oscar V. Bryan Colonel Base Civil Engineer on April 27, 1993, on May 7, 1993 by ADEC Project Manager Jennifer Roberts and USEPA Project Manager Marcia Combes. |
Jennifer Roberts |
| 9/15/1994 |
Risk Assessment Report Approved |
Risk assessment combined with RI/FS final version received and approved. 12 constituents were identified as major contributors to groundwater risk. 8 were identified as contributors to carcinogenic groundwater risk: benzene, chloromethane, dieldrin, 1,1-dichloroethene, 1,2-dichloroethane, chloroform, trichloroethene, and carbon tetrachloride. 4 constituents were principal contributors to non-carcinogenic groundwater risk, including toluene, ethylbenzene, cis-1,2-dichloroethene, and trichloroethene. Results of the risk evaluation for soils indicated six constituents as primary contributors to the carcinogenic risk in soil, including benzo(a) pyrene, benzo(b)fluoranthene, dibenzo(a,h)anthracene, benzo(a)anthracene, PCB-1260, and benzo(k)fluoranthene. Non-carcinogenic risk in soil did not exceed an HQ of 1.0.
The results of the risk assessment indicate that each of the six soil and five of the six groundwater areas of interest have a carcinogenic risk in excess of 1.0 x 10-6 using the most conservative residential estimates. At the Asphalt Drum Storage Area, no groundwater risks were identified.
Ecological risk assessment: Ecological quotients for moose did not exceed 1.0 for moose. EQs of 1.0 were exceeded for copper and lead for meadow voles at OU4. None of these exceedances appear to be highly significant for the following reasons: the overall nature of the methodology used was conservative. In several cases the calculated doses, reference criteria, or measurement endpoints were inappropriate for this site because even normal background concentrations caused exceedances. Finally, the relatively uniform distributions of concentrations of manganese, selenium and thallium across all the sites is not typical of highly contaminated areas. |
John Halverson |
| 9/15/1994 |
Site Characterization Report Approved |
Remedial investigation/feasibility study final version received and approved.
NOTE: RI states: Hangar 14 RI Groundwater screening results: NH-13 5.3 ug/L TCE, NH-16 benzene 87 ug/L NH-20 benzene 140 ug/L This "plume" of benzene is unique in that no BTEX constituents other than benzene were detected. A sample of groundwater from NH-20 was submitted for quick turnaround analysis for method 8240. This was done to verify both the concentrations and identification of benzene by the field GC. The results were confirmed and a result of 124 ug/L for benzene was detected in this groundwater sample.
OU4W-14 had benzene at 207 ug/L and 155 ug/L This well was installed to specifically confirm the presence of benzene at this location. Likewise OU4W-15 and OU4W-16 were installed at upgradient and downgradient locations to define the extent of benzene contamination. Hangar 14 had the highest overall occurrences of nitrate/nitrite at OU 4. Concentrations of up to 48 mg/L were detected. Pure benzene is rarely used as an industrial agent and the use of it at an Air Force facility is hightly unlikely.
A potential source would be migration of BTEX constituents from an upgradient location; however no upgradient facilities which might be likely sources have been identified. It is possible that former landfills or buildings in the area might have been a contributor to BTEX contamination in the past, but it is unlikely that isolated benzene would be detected as the residual contaminant.
Nitrate/nitrite sources could be from residue from fertilization of vegetative cover, and runoff of deicing agents containing urea.
See site file for additional information. |
John Halverson |
| 12/7/1994 |
Update or Other Action |
Mgt. Action Plan Appendix G No Further Action Documents.
Source area SD26 within OU4 (Hangar 14/Building 43-550) is an active maintenance hangar for C130 propellers and engines. It is located approximately 1,500 feet southeast of Burns Road and about 2,000 feet west and 1,300 feet south of the north end of the north/south runway.
Historical records available for source area SD26 indicate that from 1970 through the early 1980s, waste engine oil, hydraulic fluids, JP-4, and PD680 were produced at the facility. Some of these waste materials were washed into floor drains that were reportedly connected to dry wells. The floor drains and latrines are currently connected to the sanitary sewer.
Source area SD26 was originally identified as a potential source of contamination in
the 1983 Phase I record search. This site is included in OU4 for purposes of remedial
investigation at Elmendorf AFB under CERCLA. Ten maintenance facilities were grouped together in OU4 for LFI during 1992.
A 1992 LFI was conducted at source area SD26 to identify and evaluate the drain outfalls at Building 43-550 and to assess the possible environmental impacts that may have resulted from past operations and disposal practices. The results of the LFI were used to assess the final disposition of the outfall and to recommend either NFA or that an RI/FS be conducted.
As a result of the LFI and the research of other potential contaminant sources, it was determined that source area SD26 is not a source of the groundwater contamination observed in the area. The recommended action for the floor drains and outfall structure investigated at SD26 was NFA.
The NFA document for SD26 was signed by the USAF on 27 April 1993 and by the state and EPA on 7 May 1993. Site SD26 was considered closed with the signing of the NFA document. |
Louis Howard |
| 4/11/1995 |
Proposed Plan |
SD26 (a.k.a. Building 43-550, Hangar 14) listed in the Proposed Plan for GW contamination (benzene). No soil contamination found exceeded Alaska cleanup matrix criteria. Institutional controls and intrinsic remediation (IC/IR) was the preferred alternative for groundwater contamination (7 years to cleanup to MCLs). This source area while recommended for No Further Action, is still included within OU4 and the groundwater will be addressed. Benzene was the sole contaminant of concern identified with a maximum concentration of 207 ug/L and the cleanup level is 5 ug/L for benzene. A plume 500 feet southwest of hangar 14 was estimated to be 300 feet by 150 feet with no other fuel related constituents identified in this plume. |
Jennifer Roberts |
| 6/15/1995 |
Site Ranked Using the AHRM |
Initial ranking. Action code added because it wasn't when the site was originally ranked. |
Louis Howard |
| 7/1/1995 |
Long Term Monitoring Established |
Round 1 of the groundwater sampling occurred and report received. |
Louis Howard |
| 10/10/1995 |
Cleanup Level(s) Approved |
Benzene was the sole contaminant of concern identified for groundwater with a maximum concentration of 207 ug/L and the cleanup level is 5 ug/L for benzene. |
Jennifer Roberts |
| 10/10/1995 |
Institutional Control Record Established |
Institutional Controls and monitored natural attenuation for contaminated groundwater (GW) estimates state that the GW will cleanup within 13 years. ICs on land use and water use restrictions will restrict access to the contaminated GW until cleanup levels have been reached. GW will be monitored and evaluated semi-annually to assess contaminant migration and timely reduction of contaminant concentrations by IR. This will include 5 year reviews to assess the protectiveness of the remedial action as long as contamination remains above cleanup levels. These assumptions are predicated upon there being no additional leaks or spills occurring at the source area. |
Louis Howard |
| 10/10/1995 |
Record of Decision |
ROD identifies one GW plume composed of benzene 500' SW of hangar 14. The ROD also lists the deep and shallow soils to be cleaned up within 4 years even though levels present are below the Alaska cleanup matrix criteria. ROD states hangars 10, 11, 14 (SD 24, 25 and 26) GW contamination will be intrinsically remediated and have institutional controls (ICs) on land use and water use restrictions to restrict access to the contaminated GW until cleanup levels have been met.
Deep soils at the FTA, the ADSA, and Hangar 10/11 [SD24/SD25] will be treated with bioventing to accelerate degradation of contaminants in those locations. Deep soils at other source areas will be allowed to degrade through intrinsic remediation. The Air Force will investigate and implement other remedial alternatives should the selected remedies prove to be unsuccessful at meeting the required cleanup levels.
Specific components of the selected remedy consist of the following:
Groundwater
* Institutional controls on land use and water use restrictions will restrict access to the contaminated groundwater throughout OU 4 until cleanup levels have been achieved.
* Groundwater will be monitored and evaluated semi-annually to assess contaminant migration and timely reduction of contaminant concentrations by intrinsic remediation. This will include five-year reviews to assess the protectiveness of the remedial action, as long as contamination remains above cleanup levels. A monitoring plan will be prepared to address the details involved in sampling.
* All groundwater is expected to be cleaned up within thirteen years.
Soil
* Institutional controls on land use will restrict access to the contaminated shallow soils throughout OU 4 until cleanup levels have been achieved.
* Deep soils at specified locations and depths at the FTA, the ADSA, and Hangar 11 will be treated with bioventing to accelerate degradation of contaminants in those locations. Deep soils at other source areas will be allowed to degrade through intrinsic remediation.
* Both shallow and deep soils will be monitored and evaluated bi-annually to assess contaminant migration and timely reduction of contaminant concentrations by intrinsic remediation. This will include five-year reviews to assess the protectiveness of the remedial action, as long as
contamination remains above cleanup levels.
* When concentrations in the bioventing areas are below cleanup levels, bioventing will be discontinued. A monitoring plan will be prepared to address the details involved in sampling.
* All soils are expected to be cleaned up within eleven years.
The remedy will be implemented after the Remedial Design has been completed. A treatability study for bioventing design is currently in progress. Bioventing will be implemented until cleanup levels have been achieved. The actual timeframe for intrinsic remediation at the other source areas is not known, but groundwater and soil modeling predict cleanup levels will be achieved in 10 to 15 years.
Groundwater and soil will both be monitored to evaluate the progress of intrinsic remediation processes. Further response actions, coordinated with the regulatory agencies, may be considered if monitoring finds unacceptable contaminant migration occurring, or unacceptable reduction in contaminant concentrations through intrinsic remediation.
NOTE TO FILE: § 300.430 Remedial investigation/feasibility study and selection of remedy.(a) General—(1) Introduction. The purpose of the remedy selection process is to implement remedies that eliminate, reduce, or control risks to human health and the environment. Remedial actions are to be implemented as soon as site data and information make it possible to do so. Accordingly, EPA has established the following program goal, expectations, and program management principles to assist in the identification and implementation of appropriate remedial actions.
(iii) Expectations. EPA generally shall consider the following expectations in developing appropriate remedial alternatives:
(D) EPA expects to use institutional controls such as water use and deed restrictions to supplement engineering controls as appropriate for short- and long-term management to prevent or limit exposure to hazardous substances, pollutants, or contaminants. Institutional controls may be used during the conduct of the remedial investigation/feasibility study (RI/FS) and implementation of the remedial action and, where necessary, as a component of the completed remedy. The use of institutional controls shall not substitute for active response measures (e.g., treatment and/or containment of source material, restoration of ground waters to their beneficial uses) as the sole remedy unless such active measures are determined not to be practicable, based on the balancing of trade-offs among alternatives that is conducted during the selection of remedy. |
Louis Howard |
| 10/10/1995 |
Update or Other Action |
ROD formalized this source area along with SD27, SD30, and SS18 as having minimal soil contamination and designated as no further action sites. |
Louis Howard |
| 8/18/1996 |
Update or Other Action |
Round 1 for 1996 Groundwater monitoring received. |
Louis Howard |
| 10/17/1996 |
Update or Other Action |
Air Force memo: Restricted Use of the Shallow Aquifer on EAFB signed by William R. Hanson P.E. GM-14 Chief Environmental Flight dated October 17, 1996 Memorandum for 3 SPTG/CEC/CEO from 3 SPTG/CEV.
1) Due to the contamination and commitments to EPA/DEC the use of the shallow aquifer for any purpose on is not allowed. Attached Facilities Board minutes-03/29/1994 0930 Item 9 has Mr. William Hanson, briefing the Board on the policy to not use the shallow aquifer due to contamination. The Board approved this policy. Minutes approved by Thomas R. Case Brigadier General USAF Commander. The IRP has RODs for OUs 3 and 6 which require, the aquifer remain unused.
2) Personnel in the review process within CES must be aware of these policies and review them on a recurring basis. It is imperative this restriction be recognized and observed during engineer reviews and operations. |
Louis Howard |
| 12/6/1996 |
Update or Other Action |
Round 2 Base-wide groundwater monitoring results received for OU4. 1,1-Dichloroethane 7.76 ug/L and no other contaminants found in groundwater above action levels. |
Louis Howard |
| 6/16/1997 |
Update or Other Action |
USAF Memorandum to ADEC regarding Clarifications to OU2 ROD. The letter is a follow-up to the discussions regarding institutional controls at OU2. The USAF hopes by this correspondence, to clarify appropriate land use controls at OU2 and setup a land use restriction method consistent with the most recent Elmendorf RODs. The OU2 ROD states that groundwater at ST41 needs remedial action and a part of the selected remedy was to restrict land use by implementing zoning controls. The Summary of the ROD on page 9-2 states that the selected remedy includes "Zoning the affected area for industrial use only, excluding the development of commercial aquaculture."
However, the Declaration of the ROD states "Zoning the affected area for undeveloped outdoor/recreational use only." In light of this contradiction and the use of "restricted use areas" under the RODs for OU3 and OU6 the USAF is providing clarification of the permissible land uses within the area affected by ST41 groundwater. The affected area should include those areas that exceed the groundwater cleanup levels established in the OU2 ROD. A map of the area currently and potentially impacted by the contaminated groundwater from ST41 is at Attachment 1. This map may be revised based upon review of the contamination remaining in place, which will be conducted at least every 5 years. While the affected area remains above cleanup levels, it will be designated as a "restricted use area" in the base Planning Office. This designation provides for recreational use of the parcel (such as cross country skiing, bicycling, etc.) and the construction of unmanned facilities (such as parking lots, storage buildings, etc.) but prohibits the construction of any manned facilities (such as office buildings or a residence). Construction activities within the affected area of OU2 will be restricted to construction of unmanned facilities. Furthermore no construction will be allowed which comes within five feet of the groundwater. Existing industrial uses within OU2 are allowed as they are unmanned. This description conforms to the current base land use planning terminology and is consistent with the recently signed RODs for OUs 3 and 6. Land use restrictions will be enforced by the following method. When there is a construction project on Base, the project is to be approved by the Base Planning Office. The planner will route all projects through the Environmental Management Office. The project will be disapproved if it conflicts with the above construction restrictions. The USAF believes this will be a reliable and effective means of enforcing the zoning land use restrictions imposed by the various RODs. Signed by Randy E. Honnet Colonel USAF Vice Commander. |
Louis Howard |
| 9/9/1997 |
Update or Other Action |
Round 1 groundwater monitoring results received. |
Louis Howard |
| 8/15/1998 |
Update or Other Action |
Round 1 groundwater monitoring results August 1998. |
Louis Howard |
| 10/1/1998 |
CERCLA ROD Periodic Review |
Five year review: OU4 consists of 10 source areas which include floor drains in eight maintenance facilities (SD24 through SD30 and SS18), a fire training area (FT23), and an asphalt drum storage and processing area (SS10). Eight of the ten source areas in OU4 are located north of the east-west runway and south of the Elmendorf Moraine. The remaining two source areas (SD30 and SS 18) are located south of the east-west runway, near 2nd Street between OUs 3 and 5. Due to minimal soil contamination at SD26, SD27, SD30, and SS18, these sites have been designated as NFA sources and decision documents were signed in May 1993. HOWEVER, groundwater is impacted (RI/FS 1994 Table 7-3 page 7-19) with benzene (207 ug/L) and. dieldrin (0.0335 ug/L).
The OU4 ROD (USAF, 1995a) was signed in October 1995, and the major components of the
selected remedy include:
* Intrinsic remediation I will be relied upon to attain cleanup levels in the contaminated
shallow aquifer. Groundwater will be monitored semiannually to evaluate contaminant
migration and timely reduction of contaminant concentrations.
* Until cleanup goals are achieved, institutional controls that prohibit the use of the
shallow aquifer will ensure that people will not be exposed to contaminated
groundwater.
All remedial actions are operational and functional, as documented in the OU4 RA report. Bioventing and monitoring are continuing at all OU4 locations in accordance with the bioventing performance and monitoring plan (USAF, 1996b). For shallow soils, sufficient intrinsic remediation has occurred such that cleanup goals have been reached at SS10 and SD25 (Hangar 11). No further monitoring of shallow soils is being done at these sites. Institutional controls have been established and are being maintained to prevent exposure until cleanup goals are attained throughout OU4.
Bioventing systems and monitoring wells have been inspected and are in good condition. One
groundwater monitoring well may need to be reconfigured to a flush mount to accommodate
flight operations. Based on review and evaluation of 1997 soil and 1997 and 1998 groundwater monitoring data, COCs in deep soils still exceed cleanup levels for fuel-related constituents (DRO, GRO, and jet fuel). Also, groundwater in the shallow aquifer still exceeds cleanup goals for benzene, ethylbenzene, toluene and certain waste solvents. Summaries of monitoring data and
information are available in the 1997 Groundwater Monitoring Annual Report. Due to current land use and institutional controls, there is no human exposure to the groundwater (or contaminated soils). Response actions at OU4 are expected to continue for another 11-12 years to address groundwater, based on site data and current estimates of the time to remediation documented in the 1997 Groundwater Monitoring Annual Report. |
Jennifer Roberts |
| 11/1/1998 |
Update or Other Action |
Round 2 groundwater monitoring received. |
Louis Howard |
| 11/8/1999 |
Update or Other Action |
The location of a former 500-gallon UST (tank 31-338) that was primarily used to store JP-4 jet fuel waste from fuel truck maintenance activities. The UST was removed in August 92, and replaced with a 1,200-gallon UST (31-338A) in an adjacent location.
The depth to groundwater in well 49WL01 located approximately 150 feet south-southwest of the site, was measured at 13.59 feet below ground surface (bgs). The depth to groundwater in the bioventing vent well was measured at 11.53 feet bgs. Shallow groundwater is not currently used as a drinking water source and is unlikely to be used as one in the future. Contaminant of concerns (COCs) with initial contamination levels are as follows:
Initial Contamination Levels for Soil Water
Diesel Range Organics (DRO) 860 mg/kg 9,700 ug/l
Gasoline Range Organics (GRO) 3,600 mg/kg 9,700 ug/l 9 Benzene .033 mg/kg 740 ug/l
Toluene 1.3 mg/kg 35 ug/l
Ethylbenzene 4.9 mg/kg 95 ug/l
Total xylenes 80 mg/kg 1,300 ug/l
STATEMENT OF BASIS-This decision is based on the following attached references:
a. Site ST71 from SERA Phase I Corrective Action Plan (CAP), Final, Apr 95
b. Alaska Department of Environmental Conservation's (ADEC) 27 Feb 97 Ltr
c. Table 4-17, Basewide Annual Groundwater Report, Final, Mar 98 (49WL01)
d. Site Closure Report for Site ST71, Nov 96 (refer to your copy)
e. Table 5-8, Basewide Annual Groundwater Report, Final, Jun 99 (49WL01)
f. Table 2-4, Basewide Monitoring OU4-Round 1, Aug 99 (49WL01)
DESCRIPTION OF THE SELECTED REMEDY-No further remedial action remedy is based on the field sampling conducted on 28 May 96 pursuant to closure of site ST71 on base. All of the laboratory analytical results for vadose zone soil were below ADEC (1995) Category A soil cleanup levels for all analytical methods. These results indicate that petroleum hydrocarbons in the vadose zone soil at the site have been remediated to the applicable matrix cleanup levels during the operation of the bioventing system.
Monitoring well 49WL01 has been added to the OPERABLE UNIT (OU)4 monitoring program. With the exception of benzene concentrations in groundwater at down gradient well 49WL01 (14.9 ug/l), GRO (930 mg/kg at 49BH07-12 and 500 mg/kg at 49BH08-13), and DRO (1,600 mg/kg at 49BH07-12) concentrations in saturated soil samples, this site meets all applicable state cleanup goals. Contaminated soil below the watertable is not effectively remediated through bioventing.
The vadose zone soil was below ADEC (1995) Category A soil cleanup levels for all analytical methods. This has allowed the bioventing system at this site to be turned off in 1997 and will be removed in the future. The groundwater contamination is under the cleanup levels in Table C using the criteria outlined by 18 AAC 75.345 (b)(2)(A)&(B). In addition, the wetland remediation system constructed on the Ship Creek flood plain prevents ST71 contamination from leaving the base property boundary. Therefore, there is no further requirement for tracking conditions at ST71. Monitoring well 49WL01 has been added to the OPERABLE UNIT (OU)4 (Basewide) monitoring program.
If any information is presented in the future that indicates contamination from this project area is present (above established cleanup levels) and/or poses a risk to the public's health or the environment, then additional assessment and corrective action may be necessary. The location of this monitoring well is useful to track trends of trichloroethene (TCE), dichloroethene (DCE), and chloride concentrations in the outwash plain. The remedy of no further remedial action under the ERP is selected because the contaminant levels at the site present no significant threat to human health or the environment; thus, no treatment is necessary. |
Louis Howard |
| 2/21/2002 |
Document, Report, or Work plan Review - other |
Staff reviewed and commented on the annual base-wide groundwater monitoring report.
Regulatory Levels
ADEC requests removing the word “Potential” from the heading “Potential Regulatory Level” in the tables throughout the document. Listing the word “Potential” gives the reader the impression that compliance with the levels listed is optional or not required (e.g. Tables 4-7, 4-11, 4-15, 4-20, 4-25, 4-29, 4-32, and 6-2).
Free Product
Please note 18 AAC 75.325(f) states: A responsible person shall to the maximum extent practicable,
(A) use permanent remedies;
(B) recover free product in a manner that minimizes the spread of contamination into an uncontaminated area by using containment, recovery, and disposal techniques appropriate to site conditions.
ADEC recognizes that in some cases it may not be technically practicable to implement an active or passive recovery system for free product. The Elmendorf Remedial Action Report for Operable Unit (OU) 2 (September 1998) set a precedent for defining what is meant by “technically practicable” for free product recovery. Section 2.4.1 Product Recovery Endpoints at the 1st bullet on page 10 states: “As designed and constructed, the ST41 ground water treatment system cannot recover floating product when there is less than a measurable thickness of 0.1 feet of product. Therefore, as an endpoint for product recovery, if less than 0.1 feet is sustained for one year, recovery at that source can be discontinued. Floating product will be measured monthly. When product thickness falls below 0.1 feet for one year, the recovery of product at that source will not be considered “technically practicable”.
Therefore, where free product is greater than 0.10 feet, ADEC expects corrective action (active or passive) to be implemented for free product recovery. Currently, free product was found to exceed 0.10 feet or more in SERA Phase I well 43-WL-11. This well had the highest level of free product measured at 0.86 feet. The presence of measurable free product is generally not considered conducive for intrinsic (natural) attenuation. ADEC requests the identity of the free product be described in the text at each source area that it is found (e.g. gasoline, diesel, or chlorinated solvents).
3.3.4 Target Analytes Pages 3-10 and 3-11
Benzene and TCE are identified as target analytes to evaluate contaminant of concern (COC) trends in detail and be consistent with the Base wide Groundwater model. ADEC concurs, however, focusing on these two analytes does not accurately reflect whether diesel range organics (DRO) and gasoline range organics (GRO) plumes are migrating, expanding, steady state, or receding (especially for wells noted to have either free product or fuel odor and/or sheen being observed during sampling). Benzene can be at low levels or even non-detectable while concentrations of DRO and GRO remain above cleanup levels (1.5 mg/L and 1.3 mg/L respectively). Please see the following examples below of where benzene was below the 5 ug/L cleanup level, but DRO and GRO are above cleanup levels.
OU 4
Round 1 sampling at well 49-WL-01 detected benzene at 0.11 ug/L and DRO at 2,400 ug/L and well OU4W-11 detected benzene at 4.3 ug/L while GRO was detected at 3,000 ug/L and DRO was detected at 6,100 ug/L.
OU6
Round 1 sampling at well OU6MW67 detected benzene at 2.8 ug/L, GRO at 2,500 ug/L and DRO at 1,700 ug/L during round 1 sampling. During round 2 sampling, well OU6MW-91 detected GRO at 25,000 ug/L and DRO at 9,500 ug/L while benzene was found to be non-detectable.
See site file for additional information. |
Louis Howard |
| 7/2/2004 |
Site Number Identifier Changed |
Changed the Work plan from X1 to X9 due to the presence of metals and hazardous substances above cleanup levels. |
Former Staff |
| 6/7/2013 |
Exposure Tracking Model Ranking |
Initial ranking with ETM completed for source area id: 71622 name: auto-generated pm edit Elmendorf OU4 SD26 Bldg. 42-550 |
Louis Howard |
| 3/31/2021 |
Document, Report, or Work plan Review - other |
DEC reviewed the "Draft JBE054 N/S Runway Extension Site Investigation UFP-QAPP" dated March 2021 and provided comments to the U.S. Air Force via email. The intent of the investigation is to characterize the nature and extent of soil contamination within the footprint of a proposed runway extension. |
Melinda Brunner |
