| Action Date |
Action |
Description |
DEC Staff |
| 12/12/1994 |
Update or Other Action |
Final Site assessment for Underground Storage Tank No. 165 dated December 1994, F41624-92-D-8006, Order No. 0015. Based on the field investigation, UST 165 is a 750 gallon carbon steel, underground storage tank located in the central portion of the Base on the north side of Building 11-160. The UST was installed on January 1, 1982 and used to store waste oil. As part of the site assessment, two soil borings were installed near the UST in accordance with ADEC requirements. One sample was collected from each boring and analyzed. Results of the site assessment do not show waste oil related contaminants in the soil exceeding cleanup levels.
One sample was collected from each boring at 13 to 14.5 feet below ground surface (bgs) and analyzed for gasoline-range organics (GRO); diesel-range organics (DRO); benzene, toluene, ethylbenzene, and xylenes (BTEX); total recoverable petroleum hydrocarbons (TRPH); halogenated volatile organic compounds (HVOCs); polychlorinated biphenyls (PCBs); arsenic; cadmium; chromium; and lead.
Benzene, methylene chloride, and vinyl chloride were non-detect; however, the laboratory reporting limits (LRLs) (0.026 to 0.027 milligrams per kilogram [mg/kg] for benzene, 0.11 mg/kg for methylene chloride, and 0.053 to 0.054 mg/kg for vinyl chloride) are greater than the ADEC 18 AAC 75, Method Two (January 2003) cleanup levels (0.02, 0.015, and 0.009 mg/kg, respectively). Arsenic results were within the normal range of background concentrations for Elmendorf AFB. All other results were below cleanup levels.
It is recommended that UST 165 be permanently closed. |
Louis Howard |
| 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. |
Louis Howard |
| 6/1/1995 |
Leaking Underground Storage Tank Release Confirmed - Petroleum |
LUST Site created in CSP for source area ID 75983 |
Former Staff |
| 6/1/1995 |
Leaking Underground Storage Tank Cleanup Initiated - Petroleum |
|
Former Staff |
| 6/1/1995 |
Site Added to Database |
|
Former Staff |
| 10/12/1995 |
Update or Other Action |
UST Site Assessment Report HUSH House Tank, Elmendorf AFB, Contract # DACA85-94-D-0014, DO# 0004, Submitted to Linder Construction Inc. and submitted by AGRA Earth & Environmental, 31-01568, dated October 1995. The UST removal and assessment occurred from June 29, 1995 to July 14, 1995. Soil excavation work began on June 29, 1995. Soils surrounding the oil/water separator vault were excavated on July 5, 1995.
Soil samples collected beneath the separator's vault and on the north excavation wall adjacent to the separator. SS-4: 2,700 mg/kg TPH, 2,100 mg/kg DRO, 96 mg/kg GRO, 2.63 mg/kg BTEX. Sample SS-5: 5,400 mg/kg TPH, DRO 7,000 mg/kg, GRO 730 mg/kg, BTEX 57.26 mg/kg (sample 55-5). No groundwater samples were analyzed. 80 cubic yards of soil were removed and thermally treated. The sludge sample SS-9 from the contents of the tank was reported to contain: 68,000 mg/kg TPH, 45,000 mg/kg DRO, 1,300 mg/kg GRO, 94.3 mg/kg BTEX, 12 mg/kg Cd, 130 mg/kg Cr, 78 mg/kg lead. It was non-detect for HVO, PCBs, arsenic, and TCLP lead.
Based on the field and analytical data collected at this site, further site assessment and/or remediation activities are required at this site. Specifically, hydrocarbon impacts greater than the regulatory limits are still present below the former oil/water separator location and in the soil adjacent to the building foundation. |
Louis Howard |
| 3/12/1997 |
Update or Other Action |
Environmental Compliance Program, AFID 165, SERA Phase IV ST410 Release Investigation Report, Draft Final Dated March 1997. ST410 is a former underground storage tank (UST) and oil-water separator site at the Old HUSH House (bldg. 11-140). The UST had a 500 gallon capacity and contained waste oil. The separator was housed in a concrete vault west of the UST. The piping systems associated with the separator and UST were also known to leak and the tank failed a tightness test (AGRA 1995). The 1996 release investigation detected BTEX at 34.94 mg/kg, GRO at 750 and 221 mg/kg, DRO at 3,600 and 2,690 mg/kg. Site disposition recommendations for AFID 165/ST410 will be submitted under separate cover pending the completion of risk assessment work on the affected areas. |
Louis Howard |
| 8/21/2002 |
Update or Other Action |
RECKEY has automatically been generated. |
Cynthia Pring-Ham |
| 10/21/2002 |
Update or Other Action |
Jennifer Roberts (DEC Federal Facilities) 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. |
Louis Howard |
| 4/26/2004 |
Update or Other Action |
Decision document received. Elmendorf Air Force Base (AFB) site ST410 is located south of Building 9561 (formerly Building 11-400), a Hush House for jet engine testing. This building has also been referred to as former building number 11-162; however, historical documents refer to it as Building 11-400. The site is located near the intersection of Slammer Avenue & Simpson Harbor Drive. This site is located on the south side of the East/West Runway & is within the Operable Unit 5 (OU5) modeling area.
UST Removal: The UST & OWS were removed in June & July 1995. Five soil samples were collected from the excavation & analyzed for GRO, DRO, BTEX, total petroleum hydrocarbons (TPH), HVOCs, PCBs, arsenic, cadmium, chromium, & lead (Figure 1). Three of the samples also were analyzed for polynuclear aromatic hydrocarbons (PAHs). Sample SS-5 contained 730 mg/kg GRO, 7,000 mg/kg DRO, 0.96 mg/kg benzene, & 9.8 mg/kg toluene, which exceeded Method Two cleanup levels (300 mg/kg, 250 mg/kg, 0.02, & 5.4 mg/kg, respectively). Only DRO (2,100 mg/kg) exceeded cleanup levels in sample SS-4.
There is no evidence that arsenic or HVOCs are present at the site. Benzene was detected in two other samples; therefore, it could be present in the three samples with non-detect results. All other analytical results were below Method Two cleanup levels.
During the removal of the tank, approximately 0.5 liter of liquid was released from the tank to the soil. Impacted soil was excavated & added to the suspected contaminated soil stockpile. One sample was collected from the 80 cubic yards (cy) of suspected contaminated soil & analyzed for GRO, DRO, BTEX, TPH, HVOCs, PCBs, arsenic, cadmium, chromium, & lead. GRO (840 mg/kg), DRO (12,000 mg/kg), benzene (0.73 mg/kg), & toluene (6.1 mg/kg) exceeded Method Two cleanup levels; therefore, this soil was transported offsite for thermal treatment. As with the samples collected from the excavation, arsenic & HVOCs were non-detect but the LRLs exceeded the cleanup levels.
SERA IV: During the State-Elmendorf Environmental Restoration Agreement (SERA) Phase IV investigation conducted in 1996, four borings were installed. One boring was completed as a bioventing injection well & three borings were completed as piezometers. The bioventing injection well was screened above the saturated zone; therefore, it cannot serve as a monitoring well. Soil samples were collected from each boring at approximately 5-foot intervals for lithologic logging & field screening.
Two samples from each boring were analyzed for GRO, DRO, residual-range organics (RRO), & BTEX. GRO (750 mg/kg) & DRO (3,600 mg/kg) exceeded Method Two cleanup levels in the sample collected near the former OWS vault at 16 feet bgs. Benzene was non-detect; the LRL was 0.05 mg/kg & the method detection limit was 0.01 mg/kg. All other results were below cleanup levels.
The selected remedy for this site is monitored natural attenuation. GRO, DRO, benzene, & toluene concentrations in soil exceed the ADEC 18 AAC 75 Method Two (January 2003) cleanup levels at this site. Based on SERA investigation results, elevated contaminant concentrations ST410 are located from approximately 14 feet bgs to the groundwater interface.
Excavation is NOT recommended because the highest levels of contamination were detected next to the building foundation & the highest contamination levels were detected from 14 to 26 feet bgs. The replacement UST & OWS installed at this location are currently in-use & support mission-critical operations at the Hush House. The area is covered by asphalt & located in a secure fenced area on the airfield.
This site is located within the OU5 modeling area as identified in the Operational Agreement (OA) between ADEC & Elmendorf AFB signed 28 July 2002. In the OA, both parties agree that the portion of the unconfined shallow aquifer in the outwash plain has demonstrated, through modeling & sampling, the ability to naturally attenuate residual hydrocarbon contamination from most petroleum, oil, & lubricant (POL) spills in a reasonable period of time.
The Elmendorf AFB Basewide Groundwater Monitoring Program WILL be utilized to monitor groundwater during implementation of the remedy. The nearest downgradient monitoring well currently in the Basewide Groundwater Monitoring Program is 61-WL-02, located approximately 600 feet southwest of ST410. |
Louis Howard |
| 4/1/2005 |
Update or Other Action |
2004 Phase I RPO Annual Report received for groundwater performance optimization monitoring program.
Source Delineation
The upgradient source of chlorinated solvents at the Slammer Avenue Plume has not been well
defined. However, two source areas, ST46 and SD40, correspond with the downgradient portion
of the plume and are related to fuels contamination. These source areas were identified in the
OU 5 RI/FS (USAF, 1994d) and are related to a multi-product fuel pipeline corridor that
parallels the bluff.
Specifically, source area ST46 was caused by a JP-8 fuel line leak, and source area SD40 is probably related to a poorly documented railroad maintenance operation.
Additional fuel releases along the pipeline corridor occurred between the late 1950s and the late 1970s (USAF, 2003c). Contaminants found in Beaver Pond sediments during the OU 5 RI/FS
included JP-8, diesel fuel, gasoline, BTEX components, and heavy metals. Water samples contained BTEX components, gasoline, and several chlorinated solvents, including TCE.
The OU 5 RI did not identify an upgradient source of TCE for the Slammer Avenue Plume. TCE
had been commonly used as a degreasing agent in flightline shops decades ago. Sources of TCE
contamination are typically related to drain leaks and disposal sites associated with such
maintenance shops. High levels of TCE and low levels of daughter products in monitoring wells
OU5MW-06 and OU5MW-07, which are both approximately 400 feet north of the bluff edge
and consequently unrelated to the fuel pipeline, indicate proximity to a source of chlorinated
solvents.
The northern boundary of the plume is well defined by a low level of TCE measured in 61WL-07. Sampling in 2002 at wells 61WL-01 and 61WL-02 resulted in low levels of TCE and delineated the northern boundary of the plume (USAF, 2003c). Although the upgradient OU 2 UST site ST20 was reportedly used to store used solvents and other waste from industrial shops (USAF, 1998), the groundwater COC data from 61WL-01 and 61WL-02 indicate that ST20 is an unlikely source. Several State Program Sites are also located upgradient of the Slammer Avenue Plume, but can be eliminated as potential source areas because chlorinated solvents have not been found in wells used to monitor those sites.
Although no source areas were identified in the records search, the direction of groundwater
indicates that the Cope-T Ramp (South) and Taxiway D South portions of the airfield are a
potential source area location. Maintenance shop activities in this area could be a potential
source of contamination, although a specific point source has not been identified and
investigations have not been performed in this area. |
Louis Howard |
| 4/4/2007 |
Site Closure Approved |
Duplicate site see reckey# 199521X018001 |
Louis Howard |
| 7/7/2011 |
Exposure Tracking Model Ranking |
Initial ranking with ETM completed for source area id: 75983 name: autogenerated pm edit - Elmendorf - ST410 AFID 165 |
Louis Howard |
| 7/27/2012 |
Update or Other Action |
Draft site closure report received.
Final soil verification sampling was completed in September 2010. One in-source boring was
completed (ST410-BH01) to 30 feet below ground surface (bgs) (Attachment B). Three samples were collected from the boring: one from the upper 10 feet bgs, one from a depth between the surface and the water table (20 to 25 feet bgs), and one at or near the water table (24 to 30 feet bgs). Each sample was analyzed for previously detected contaminants (GRO, DRO, RRO, and BTEX), as well as volatile organic compounds (VOCs) and PAHs.
Maximum concentrations were 1.3 mg/kg GRO, 29 mg/kg DRO, 340 mg/kg RRO, 0.0052 mg/kg benzene, 0.130 mg/kg toluene, and 0.033 mg/kg xylenes. Various PAHs and VOCs were also detected. All detections were below ADEC 18 AAC 75.341 Method Two, Tables B1 and B2 Under 40-Inch Zone, Migration to Groundwater cleanup levels.
In accordance with State of Alaska regulation 18 AAC 75, the USAF has completed cleanup
activities at ST410, JBER-Elmendorf.
Analytical results indicate soil contamination levels are below ADEC 18 AAC 75.341 Method Two, Tables B1 and B2 Under 40-Inch Zone, Migration to Groundwater cleanup levels and groundwater contamination levels are below ADEC 18 AAC 75.345 Table C cleanup levels.
ADEC’s review and concurrence on the request for Cleanup Complete status is required in
accordance with State of Alaska environmental conservation laws and regulations. While ADEC may comment on other state and federal laws and regulations, ADEC’s concurrence on the site closure does not relieve the USAF or its consultants, contractors, subcontractors, or USAF civilian personnel from the need to comply with other applicable state and federal laws and regulations.
The site has been adequately characterized under 18 AAC 75.335 and has achieved the applicable requirements under the site cleanup rules. Cleanup at the site is complete, subject to a future ADEC determination that the cleanup is not protective of human health, safety, or welfare, or of the environment. ADEC will, as necessary to ensure protection of human health, safety, and welfare, or of the environment, require the USAF to conduct additional actions that meet the
requirements of 18 AAC 75 Contaminated Site regulations and Alaska Statute 46.03 – 46.09. |
Louis Howard |
