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Site Report: ADOTPF- Main Shop Ketchikan

Site Name: ADOTPF- Main Shop Ketchikan
Address: 5150 North Tongass Highway (4 mile), Ketchikan, AK 99901
File Number: 1516.26.023
Hazard ID: 23177
Status: Cleanup Complete
Staff: ,
Latitude: 55.377551
Longitude: -131.725088
Horizontal Datum:WGS84

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.


Two 1,000-gallon regulated underground storage tanks (USTs) are listed as release Event ID# 2598. One gas and one diesel were closed by removal in 1999; the piping run from the dispenser awning to these USTs was later found closed in-place. Release from these two USTs impacted soil from the surface to the water table at 8' below ground surface. A 40 cubic yard volume of contaminated soil was transported to and treated at a Juneau remediation facility.

Action Information

Action Date Action Description DEC Staff
9/11/2000 Leaking Underground Storage Tank Release Confirmed - Petroleum LUST Site created in CSP for source area ID 77865 (Added by System) David Allen
9/11/2000 Site Added to Database * Not Assigned
10/2/2001 Update or Other Action Changed Project Manager from Paul Horwath to Mike Jaynes Cynthia Pring-Ham
8/26/2002 Update or Other Action Project Manager change from Jaynes to Wanstall. File review and site evaluation. Tank closure adequate, Corrective Action is not. CAP for remaining contamination needed. Bruce Wanstall
5/6/2004 Leaking Underground Storage Tank Cleanup Initiated - Petroleum Sorbent pads used to remove free product from water in excavation. 40 cubic yards of contaminated material identified by headspace vapor soil screening and hydrothermally activated irridescent sheen test from single excavation to remove both USTs. Soil was transported with DEC approval to USR Juneau for thermal remediation. Bruce Wanstall
5/6/2004 Update or Other Action This property shared by DOT and DPS. Three release events from underground storage tank closures are recorded at the site with limited corrective action taken. Migration of residual soil impacts may be influenced by streams on east and west sides of the property. Bruce Wanstall
3/1/2005 Update or Other Action Noll 2003 Report reviewed; Qualified lab confirmed; Noll Environmental is not listed as qualified sampler for the Underground Storage Tank Program. 25 cubic yard contaminated soil stockpile remains on-site. Bruce Wanstall
7/18/2005 Site Visit Met shop foreman on-site to discuss history of UST closures and contaminated soil stockpile conditions. Inspected sediments and banks of streams that run along opposite sides of the property; no petroleum impacts were found. Seeps in stream banks are not present; no indication that groundwater is present beneath the former UST closure sites. No wells are located on the property or in the area to indicate existing or potential use of groundwater as drinking water source. Bruce Wanstall
5/22/2007 Site Visit Site visit to determine status of the contaminated soil stockpile; discuss soil sampling plan with facility manager Nick Barstadt; inspect stream banks for off-site GW seepage. Bruce Wanstall
6/20/2007 Exposure Tracking Model Ranking Surface soil and subsurface soil exposure routes are deminimis; exposure by future ingestion of groundwater can be controlled using institutional site controls. Bruce Wanstall
8/24/2007 Update or Other Action Review and comment on workplan for the Ketchikan ADOT&PF Maintenance Shop LUST contamination. Three monitoring wells will be installed and the contaminated soil stockpile will be assessed. Bruce Wanstall
2/7/2008 Report or Workplan Review - Other 2007 UST Groundwater Assessment Report Data meet CSP quality assurance standards. Bruce Wanstall
2/11/2008 Report or Workplan Review - Other ADEC approved the Groundwater and Soil Stockpile Assessment Report on the ADOTPF Ketchikan Maintenance Station by Shannon & Wilson. Soil samples from the stockpile were non-detect for DRO. Water samples analyzed for BTEX, GRO, DRO, and RRO were all below Table C screening levels. Bruce Wanstall
1/21/2011 Report or Workplan Review - Other ADEC evaluation of the letter-report titled Groundwater Sampling, ADOT&PF Maintenance Facility, Ketchikan, Alaska by Shannon & Wilson finds the data meet field and laboratory quality assurance criteria and is approved. The tops of the three well casings were observed to have frost-jacked cycles to heights that prevented the monument lids from securing into the monument rings. Submersible pump was used to purge the wells and collect samples. The 2010 well samples have DRO and RRO in concentrations exceeding Table C levels. Bruce Wanstall
9/2/2011 Report or Workplan Review - Other DEC evaluation of 2011 Groundwater Monitoring Report ADOT&PF Maintenance Facility Ketchikan AK by Oasis finds the site activity met the objectives of the project and an assessment of the sample collection demonstrated that a sufficient number of representative samples were collected and the precision, accuracy and completeness of the resulting analytical data is sufficient to be used to support the decision making process. In accordance with Title 18 Alaska Administrative Code (AAC) 75.360, qualified person(s) used data collection and field screening methods consistent with DEC methodology in the approved site assessment work plan. The DEC laboratory report checklist submitted as an attachment is acceptable and the data meet field and laboratory report quality assurance criteria in Contaminated Sites Program guidance documents, therefore the Report is approved in accordance with 18 AAC 75.335(d). Bruce Wanstall
3/22/2012 Exposure Tracking Model Ranking A new updated ranking with ETM has been completed for source area 77865 USTs as ID# 2598. Oasis collected samples of groundwater from wells MW-1, MW-2, and MW-3 in July 2011. Samples were analyzed for COCs DRO and RRO with parallel silica gel cleanup to remove potential biogenic compounds contributing to the contaminant levels. No DRO or RRO was detected in any of the samples from the three site wells. Bruce Wanstall
7/3/2012 Exposure Tracking Model Ranking A new updated ranking with ETM has been completed for source area 77865 USTs as ID# 2598. Bruce Wanstall
7/5/2012 Cleanup Complete Determination Issued The cleanup actions to date have served to excavate and adequately remove contaminated soil from the site. Based on the information available, DEC has determined no further assessment or cleanup action is required. There is no longer a risk to human health or the environment, and this site will be designated as closed on the Department's database. This determination is in accordance with 18 ACC 75.276(f) and does not preclude DEC from requiring additional assessment and/or cleanup action if future information indicates that this site may pose an unacceptable risk to human health or the environment. Bruce Wanstall

Contaminant Information

Name Level Description Media Comments
Benzene Between Method 2 Migration to Groundwater and Human Health/Ingestion/Inhalation Soil Benzene was detected in soil in 1999 but it did not appear in groundwater monitoring.
DRO > Human Health/Ingestion/Inhalation Soil A soil sample in 1999 far exceeded all other samples at 12,000 mg/kg at 7 ft bgs.
GRO Between Method 2 Migration to Groundwater and Human Health/Ingestion/Inhalation Soil Level detected in 1999 was 1,000 mg/kg but it was not detected in groundwater.
DRO < Table C Groundwater 3.83 mg/L was the maximum level in groundwater in 2007 but in 2011 level was below instrument detection.
RRO < Table C Groundwater RRO was at 22.4 mg/L in 2010 but in 2011 was below instrument detection.

Control Type

Type Details
No ICs Required


Description Details
Advance approval required to transport soil or groundwater off-site.

Missing Location Data

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