| Action Date |
Action |
Description |
DEC Staff |
| 6/5/2003 |
Offsite Soil or Groundwater Disposal Approved |
Air Force sent proposal to transport petroleum contaminated soil generated from a release at a heating fuel tank near Building 16716. After review, ADEC concurs with the plan to transport the petroleum contaminated soil generated from a release at a heating fuel tank near Building 16716. Under 18 AAC 78.600 Cleanup levels: General Requirements (b) ADEC will waive the requirement that a product be identified by analysis if the Air Force demonstrates that only one type of product was stored or distributed during the facility’s operational life. The Air Force has demonstrated that only heating fuel has been stored or used, in the tank and therefore a waiver for RECIEPT of lab analysis by ADEC PRIOR to treatment is authorized.
This waiver is a ONE-TIME approval for this SPECIFIC site and may not be used for any other site. Be aware that the treatment facility may require the Air Force to provide copies of the lab analysis for the soil prior to accepting it for thermal treatment. Confirmation sampling MUST be conducted to confirm the amount of contamination remaining in the excavation and at least two grab samples MUST be collected of the UNTREATED soil PRIOR to transport. Soil must be transported in covered loads from Elmendorf Air Force Base to be thermally remediated at a local treatment facility. Please submit post-treatment sampling results and scale receipts showing the total amount of soils treated referencing Bldg. 16716. ADEC’s review and concurrence on the request to thermally treat the POL contaminated soil is to ensure the proposed work is in accordance with State of Alaska environmental conservation laws and regulations. While ADEC may comment on other state and federal laws and regulations, our concurrence on the treatment does not relieve the United States Air Force (USAF) or its consultants, contractors, or AF civilian personnel from complying with other applicable laws and regulations. |
Louis Howard |
| 9/30/2003 |
Update or Other Action |
STMP 45 UST Removal Action Report Building 16716. One 20,000-gallon underground heating oil tank (HOT) for Building 16716 was removed in 2003. 6,050 mg/kg DRO remains at 17 ft. below ground surface (bgs) and 5,870 mg/kg DRO at 16 ft. bgs both located in the northwest corner of the excavation. A total of 225 tons contaminated soil was excavated and transported to ASR for thermal treatment. Groundwater is expected to be at approximately 50 feet bgs in this area and was not encountered during the removal effort. Contaminated soil was removed to the maximum extent practicable. The location of the building prevents further access to excavating additional contaminated soil.
NOTE: “practicable” means capable of being designed, constructed, and implemented in a reliable and cost-effective manner, taking into consideration existing technology, site location, and logistics in light of overall project purposes; “practicable” does not include an alternative if the incremental cost of the alternative is substantial and disproportionate to the incremental degree of protection provided by the alternative as compared to another lower cost alternative.
Further excavation activities could not be performed due to the proximity of the building's foundation and worker safety. |
Louis Howard |
| 5/25/2004 |
Site Added to Database |
DRO. |
Sarah Cunningham |
| 5/25/2004 |
GIS Position Updated |
Updated coordinates using TopoZone and Elmendorf AFB map. NAD27. |
Sarah Cunningham |
| 6/28/2004 |
Conditional Closure Approved |
The Department has reviewed the documents associated with 16716 Hangar 15 Building 16716 and concurs that the site will not require any further remediation or site investigation. The Department concurs with Air Force that further excavation at the site would jeopardize the foundation of Building 16716.
RESCINDED.
2017 Draft RI Report for SS109 states: "It was previously concluded that cleanup complete was appropriate for the UST removal area at ERP Site BLDG 16716 (CG519). Monitoring that occurred at two wells did not indicate DRO contamination in groundwater, but both locations are SOUTHWEST of contamination identified in 2016. The source area well was installed beneath the UST and did not reflect the direction of release; the “hydraulically downgradient” well was actually cross-gradient to likely groundwater flow.”
“The residual DRO contamination near the former UST removal ERP Site BLDG 16716 (CG519) appears more widespread than anticipated in site closure documentation. Fuels are not considered a Comprehensive Environmental Response, Compensation, and Liability Act (CERCLA) hazardous substance; fuel contamination is governed under State of Alaska regulations.”
24 mg/L DRO detected in groundwater grab sample from soil boring SB12 installed in 2016. |
Louis Howard |
| 6/28/2004 |
Institutional Control Record Established |
In the event that the remaining contaminated soil becomes accessible by construction and/or the removal of the foundation, or other information becomes available which indicates that the site may pose an unacceptable risk to human health, safety, welfare or the environment, the Air Force will be required under 18 AAC 75.300 to notify the Department. Also, any transport or disposal of contaminated soil excavated from the site requires approval from the Department in accordance with 18 AAC 75.325(i).
Because petroleum contaminated soil (contaminant levels higher than the Method 2 cleanup levels in Tables B1/B2 found in 18 AAC 75.341) remains at these sites, the Base Master Plan needs to be updated to document the locations of residual contamination and the need to manage contaminated soil properly. The Base Master Plan is used during the review of any construction or dig permits that could potentially encounter contaminated soils or groundwater during the project. |
Louis Howard |
| 7/23/2004 |
Site Ranked Using the AHRM |
Site ranked by project manager since it was not ranked before. |
Louis Howard |
| 7/6/2006 |
Update or Other Action |
2005 Annual Report Monitored Natural Attenuation of Basewide Compliance Program Wells received. Currently, the 3 CES/CEVQ is required by ADEC to monitor the degree to which certain regulated contaminants are naturally attenuating on 27 sites throughout the Base. The natural attenuation of each of these sites is being monitored by sampling and analyzing the groundwater under the contaminated areas and/or downgradient of the contaminated source.
In 2003, during the removal of the UST, DRO concentrations were found that exceeded the 18 AAC 75 cleanup level. Groundwater at monitoring well IS6-01, located hydraulically downgradient of the Building 16716 site, did not have detectable concentrations of DRO in 2005.
The primary recommendation for all of the sites is to perform a review of each site's conceptual site model (CSM) in 2006. The well network for each should be evaluated as part of this review.
It should be noted that the Compliance Monitoring Program is being transitioned into the Elmendorf Restoration Program in 2007. As such, the CSM review should be followed by performing a remedial process optimization (RPO) effort for all of the compliance sites so that the manner in which all of the groundwater sites on Elmendorf are monitored and evaluated will
be consistent which the two programs are merged together. |
Louis Howard |
| 6/20/2007 |
Document, Report, or Work plan Review - other |
Staff reviewed and commented on the 2006 Annual Report Monitoring of Compliance Program Sites, Elmendorf Air Force Base (EAFB) dated May 2007. ADEC concurs with the recommendations to sample 16716MW-IN for diesel range organics (DRO). |
Louis Howard |
| 7/5/2007 |
Update or Other Action |
Staff reviewed and commented on the Draft Work Plan and Field Sampling Plan Compliance Program Sites, Elmendorf Air Force Base (EAFB) dated June 27, 2007. For Building 16716 the following wells will be monitored: 16716MW-IN and IS6-01 for DRO.
ADEC has developed a technical memorandum and a Laboratory Data Review Checklist (checklist) summarizing the minimum requirements for both laboratory data packages and quality assurance (QA) summaries (data reduction, verification, evaluation, etc.). All reports submitted by the Air Force which contain analytical laboratory sample results shall contain a completed checklist and a QA summary. The latest checklist is available online at http://www.dec.state.ak.us/spar/guidance.htm#csp and must be completed, signed and dated by the firm submitting the report to ADEC. It is not to be completed by the analytical laboratory that performed the sample analysis. The summary must be included as a specific text section of the report. All laboratory results, including laboratory quality control (QC) sample results, must be reviewed and evaluated for quality, validity and usability. The text must include any effects on data validity and/or usability due to field sampling/laboratory quality control discrepancies.
Upon incorporation of comments regarding the checklist, ADEC will approve the work plans. |
Louis Howard |
| 5/20/2009 |
Update or Other Action |
Draft groundwater monitoring report received. Groundwater monitoring well 16716MW-IN was sampled and analyzed by an analytical laboratory for DRO. DRO was detected in the sample with a concentration below the cleanup level. It is recommended that soil samples be collected again from ST600 in 2015 (if funding is available) to determine if vadose zone soil contaminant concentrations have been remediated to below cleanup levels. Until soil samples are collected, annual groundwater monitoring at well 16716MW-IN should continue for DRO. |
Louis Howard |
| 4/15/2010 |
Update or Other Action |
2009 Annual Report for monitoring of compliance program sites received. Elmendorf AFB site Building 16716 is located on the east side of Building 16716, Hangar 15, on Talley Avenue, on the north side of the East/West Runway. It consists of one former unregulated 20,000-gallon steel UST used to store diesel fuel. The UST was located just outside the boiler room on the east side of the building. The UST appeared to be in good condition when it was removed in June 2003. There was no evidence of leaks; however, stained soil was observed around the fill pipe. Further subsurface investigation in 2003 indicated that a release had occurred.
Groundwater monitoring well 16716MW-IN was sampled using the approved procedures
provided in the 2008 Final Work Plan (USAF, 2008b). The sample was analyzed by an
analytical laboratory for DRO. DRO was detected in the sample with a concentration below the
cleanup level.
Following the removal of the UST in 2003, remaining DRO concentrations in soil were found to
exceed the cleanup level at this site. Annual groundwater samples, collected from 2006 to 2009,
from the in-source monitoring well 16716MW-IN did not have concentrations of DRO above
cleanup levels.
The 2008 Annual Report (USAF, 2009c) recommended that soil samples be collected again from
the Building 16716 site in 2015 (if funding is available) to determine if vadose zone soil
contaminant concentrations have been remediated to below cleanup levels continuation. ADEC
subsequently concurred with the recommendation (ADEC, 2009a). This is still recommended.
Until soil samples are collected, annual groundwater monitoring at well 16716MW-IN should
continue for DRO. |
Louis Howard |
| 7/26/2010 |
Update or Other Action |
2010 Environmental Compliance work plan received. Although Building 16716 has previously only exceeded the ADEC cleanup criterion for DRO, the soil will be analyzed for GRO, DRO, VOCs, RRO and PAHs in order to asses whether cleanup is complete. Previous groundwater sample results have indicated that contaminant concentrations in groundwater are below ADEC cleanup criteria; therefore, groundwater will not be analyzed.
If the soil analysis indicates concentrations below the ADEC cleanup criteria, no
additional samples will be collected.
If the soil analysis indicates any contaminant concentrations above the ADEC cleanup
criteria, the most appropriate path forward will be recommended based on analytical
results.
• Advance one boring to approximately 45 feet bgs in the former source area. The proposed soil boring location is presented in Figure A-12 (Appendix A).
• PetroFLAG™ screening samples will be collected and analyzed for every 5 feet of boring in accordance with ELM-SOP-1 (Appendix B).
• Three analytical samples will be collected from the soil boring: one sample will be collected from the upper 10 feet bgs; one sample will be collected at or near the water table and one will be collected from a depth between the surface and the water table.
• Analytical samples will be collected from the locations with the highest PetroFLAG™ screening results. Samples will be collected in accordance with ELM-SOP-2 (Appendix B). Samples will be analyzed for GRO, DRO, RRO, VOCs, and PAHs. |
Louis Howard |
| 7/19/2012 |
Update or Other Action |
Draft Final closure document received.
One in-source boring (BLD16716-BH01A) was advanced to 54 feet below ground surface (bgs)
during final soil verification sampling in September 2010 (Attachment B). Three samples were
collected from the boring: one from the upper 10 feet bgs (0 to 5 feet bgs), one from a depth
between the surface and the water table (40 to 45 feet bgs), and one at or near the water table
(50 to 54 feet bgs). Each sample was analyzed for GRO, DRO, RRO, volatile organic compounds (VOCs), BTEX, and PAHs.
Maximum contaminant levels of 2.2 mg/kg GRO, 18 mg/kg DRO, 100 mg/kg RRO, 0.011 mg/kg toluene, and 0.017 mg/kg total xylenes were detected at 5 feet bgs. All detections were below ADEC 18 AAC 75.341 Method Two, Tables B1 and B2 Under 40-Inch Zone, Migration to Groundwater cleanup levels. Various VOCs and PAHs were detected below cleanup levels, and benzene and ethylbenzene were not detected in any sample.
No contaminants have been detected in groundwater above ADEC 18 AAC 75.345 Table C Groundwater Cleanup Levels for five consecutive years. Soil verification sampling was completed in 2010 to determine if all soil had been remediated to below cleanup levels and support consideration for Cleanup Complete status. No contaminants were detected above ADEC 18 AAC 75.341 Method Two, Tables B1 and B2 Under 40-Inch Zone, Migration to Groundwater cleanup levels. Remaining residual contamination is below regulatory standards, and site closure is appropriate and protective of human health and the environment.
In accordance with State of Alaska regulation 18 AAC 75, the USAF has completed cleanup
activities at Building 16716, 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 |
| 7/27/2012 |
Update or Other Action |
ADEC has reviewed the site closure document and ADEC has determined the site meets the requirements of 18 AAC 75.380(d)(1). The site has been adequately characterized under 18 AAC 75.335 and has achieved the applicable requirements under the site cleanup rules. ADEC is issuing this written determination that the cleanup is complete, subject to a future ADEC determination that the cleanup is not protective of human health, safety, or welfare, or of the environment.
RESCINDED.
2017 Draft RI for SS109: "It was previously concluded that cleanup complete was appropriate for the UST removal area at ERP Site BLDG 16716 (CG519). Monitoring that occurred at two wells did not indicate DRO contamination in groundwater, but both locations are SOUTHWEST of contamination identified in 2016. The source area well was installed beneath the UST and did not reflect the direction of release; the “hydraulically downgradient” well was actually cross-gradient to likely groundwater flow.”
“The residual DRO contamination near the former UST removal ERP Site BLDG 16716 (CG519) appears more widespread than anticipated in site closure documentation. Fuels are not considered a Comprehensive Environmental Response, Compensation, and Liability Act (CERCLA) hazardous substance; fuel contamination is governed under State of Alaska regulations.”
Groundwater grab sample from soil boring installed as part of SS109 SB12 detected DRO groundwater contamination at 24 mg/L. NOTE: Solubility limit for DRO in water is ~5 mg/L. |
Louis Howard |
| 6/7/2013 |
Exposure Tracking Model Ranking |
Initial ranking with ETM completed for source area id: 75334 name: auto-generated pm edit Bldg. 16716 SMTP 445 |
Louis Howard |
| 3/30/2016 |
Institutional Control Record Removed |
Institutional Controls have been removed. |
Louis Howard |
| 11/30/2017 |
Update or Other Action |
Draft VI report received for review and comment. The southern half of Building 16716 is located within the buffer zone of a VOC groundwater contamination plume with the depth to groundwater approximately 55 feet bgs. The building is relatively airtight during normal operations. Floor penetrations include numerous floor drains, an in-floor sump/vault, and concrete floor seams. No non-VI ambient air COI contaminant sources were identified.
The maximum PCE detections in soil gas during FSE1 and indoor air during both sampling events occurred at collocated sample locations 16716-SG001 and 16716-AA001, in the southeastern corner of the facility. This soil gas location also had the consistent upward sub-slab pressure gradients noted above. There is no other spatial bias apparent in the locations of COI
detections in ambient air or soil gas.
Based on the above lines of evidence, the VI pathway is considered potentially complete at
Building 16716. The consistent detections of PCE in soil gas and indoor air suggest VI as a
potential source for these contaminants, especially in the southeastern portion of the facility.
See site file for additional information. |
Louis Howard |
| 12/6/2017 |
Site Reopened |
Draft SS109 (F-22 Weapons Release Shop) Remedial Investigation & HHRA Report-new information causes ADEC to reopen site. Additional monitoring wells installed in 2016 as part of the Remedial Investigation for SS109 WRS better defined the groundwater direction and found groundwater impacted with DRO attributed to Building 16716.
GW: Soil boring SB12 installed in 2016 detected 24 mg/L for a groundwater grab sample from 52’ bgs (DRO result is above the solubility limit of ~5 mg/L).
SOIL: 2016 results detected DRO at 1,600 mg/kg obtained from 55’ bgs (below water table). As part of the RI investigation, no other soil samples above it had DRO > cleanup level of 250 mg/kg in SB12.
"It was previously concluded that cleanup complete was appropriate for the UST removal area at ERP Site BLDG 16716 (CG519). Monitoring that occurred at two wells did not indicate DRO contamination in groundwater, but both locations are SOUTHWEST of contamination identified in 2016. The source area well was installed beneath the UST and did not reflect the direction of release; the “hydraulically downgradient” well was actually cross-gradient to likely groundwater flow.”
“The residual DRO contamination near the former UST removal ERP Site BLDG 16716 (CG519) appears more widespread than anticipated in site closure documentation. Fuels are not considered a Comprehensive Environmental Response, Compensation, and Liability Act (CERCLA) hazardous substance; fuel contamination is governed under State of Alaska regulations.”
See site file for additional information. |
Louis Howard |
| 3/25/2025 |
Cleanup Complete Determination Issued |
CG519 was reopened in 2017 because of the results from an investigation conducted at SS109 which suggested that contaminants could have been migrating from CG519. However, in 2018 an additional investigation at SS109 defined the lateral and vertical extents of fuel contamination. As a result, CG519 is no longer considered to be the source of contamination at SS109, and this site has been re-closed. Remaining contamination at adjacent SS109 will be addressed separately under File No. 2101.38.139 and Hazard ID: 25615. |
Ginna Quesada |
| 3/25/2025 |
Institutional Control Record Removed |
Institutional Controls have been removed. |
Ginna Quesada |
