Site Report: Dutch Hbr-Unalaska Vly UST 2965
| Site Name: | Dutch Hbr-Unalaska Vly UST 2965 |
|---|---|
| Address: | Former Building 2965, Upper Broadway, Unalaska, AK 99685 |
| File Number: | 2542.38.023 |
| Hazard ID: | 2886 |
| Status: | Cleanup Complete |
| Staff: | No Longer Assigned, 9074655229 dec.icunit@alaska.gov |
| Latitude: | 53.846962 |
| Longitude: | -166.504914 |
| Horizontal Datum: | WGS84 |
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We make every effort to ensure the data presented here is accurate based on the best available information currently on file with DEC. It is therefore subject to change as new information becomes available. We recommend contacting the assigned project staff prior to making decisions based on this information.
Problems/Comments
Underground Storage Tank (UST) 2965 was associated with the remnants of a former latrine, Building 2965, located on upper East Broadway Avenue in Unalaska, Alaska. During a Remedial Investigation and interim removal actions (IRA) in 1997, a single-walled steel 300-gallon UST with heavy corrosion was located on the north side of the former building. The UST and 15 cubic yards (cy) were removed from the site in August and September 1997. Three confirmation samples were collected from the base of the excavation at the bedrock interface to characterize the site. Diesel range organics (DRO) and naphthalene exceeded DEC Method Two Cleanup Levels, at concentrations of 3,100 milligrams per kilogram (mg/kg) and .086 mg/kg, respectively, in one sample.
Action Information
| Action Date | Action | Description | DEC Staff |
|---|---|---|---|
| 6/5/2000 | Site Characterization Report Approved | Comprehensive Remedial Investigation Report, dated May 2000 and prepared by Jacobs Engineering, documents the ~300 gal UST was removed in Aug. 1997; approximately 15 cy of petroleum contaminated soil were removed and thermally treated. Three confirmation soil samples were collected and analyzed for DRO, RRO, BTEX and two were analyzed for PAHs. All analytical results met the most stringent method 2 soil cleanup levels with the exception of DRO. One sample, collected ~ 7' below ground surface, contained DRO at 3,100 mg/kg, exceeding the migration to groundwater cleanup level but not the ingestion or inhalation levels. Residual soil contamination appears to be isolated in extent; due to shallow bedrock further excavation was not feasible. The report recommends no further action. | John Halverson |
| 1/23/2003 | Site Added to Database | Unalaska Valley expanded into a total of 26 unique sites from one. | John Halverson |
| 12/8/2003 | GIS Position Updated | TopoZone | Debra Caillouet |
| 6/10/2005 | Update or Other Action | File number issued 2542.38.023. | Aggie Blandford |
| 7/3/2008 | Exposure Tracking Model Ranking | Initial ranking with ETM completed. | Daniel Fremgen |
| 9/14/2010 | CERCLA Proposed Plan | ADEC received the draft final Proposed Plan #7 addressing Unalaska Valley Management Area 11. The plan recommends Alternative 1 (Corrective Action Complete/Cleanup Complete with NDAI) for UST 2965. Remaining contamination is localized in the bedrock fractures and below Method 3 ACLs, and the source has been removed to the extent practicable. | Meghan Dooley |
| 10/6/2023 | Cleanup Complete Determination Issued | On this date, a Cleanup Complete Determination was issued for the Unalaska Valley UST 2965 site. Based on the information provided to date, it has been determined that the contaminant concentrations remaining on site do not pose an unacceptable risk to human health or the environment, and no further remedial action will be required unless information becomes available that indicates residual contaminants may pose an unacceptable risk. | Cascade Galasso-Irish |
| 10/6/2023 | Exposure Tracking Model Ranking | A new updated ranking with ETM has been completed for source area 73862 UST. | Cascade Galasso-Irish |
| 2/22/2024 | Document, Report, or Work plan Review - other | On this date, DEC reviewed and approved the redline final, RTCs, and final Restoration Summary Report for the Amaknak Formerly Used Defense Sites F10AK0841-13, -14, -15, -16, -18, -20, Unalaska Valley, Pyramid Valley-Port Levashef, Summer Bay-Humpy Cove, Margaret Bay-Airport, Mount Ballyhoo, and Little South America in Unalaska, Alaska. Of the 53 sites included in this report, 39 of these sites are either closed in the Contaminated Sites database or are not eligible active sites. Fourteen (14) sites remain open in the CS database, either pending further coordination on the pathway to closure or are currently with DEC management for closure decision. This letter is documenting the approval of the final document but does not preclude the need for further investigation of sites included in the report. | Cascade Galasso-Irish |
Contaminant Information
| Name | Level Description | Media | Comments |
|---|---|---|---|
| DRO | Other | Soil | DRO concentrations at the site are below the site-specific MTG ACL for the site(8,300 mg/kg), at a maximum concentration of 3,100. |
Control Type
| Type | Details |
|---|---|
| No ICs Required |
Requirements
| Description | Details |
|---|---|
| Advance approval required to transport soil or groundwater off-site. | |
| Movement or use of contaminated material (including on site) in a manner that results in a violation of the water quality standards is prohibited (18 AAC 70) |
No associated sites were found.