| Action Date |
Action |
Description |
DEC Staff |
| 5/22/2017 |
Site Added to Database |
A new site has been added to the database |
Mitzi Read |
| 5/23/2017 |
Document, Report, or Work plan Review - other |
Soil samples collected during a Phase II Site Assessment contained DRO, RRO, benzene, ethylbenzene, xylenes, 1,2,4-trimethylbenzene, benzo(a)anthracene, and benzo(a)pyrene above cleanup levels. Benzo(a) pyrene was detected above the human health cleanup level at 1.08 mg/kg. Contamination was detected above cleanup levels to a depth of 5-7 feet bgs where a confining layer is present. |
Bill O'Connell |
| 6/5/2017 |
Document, Report, or Work plan Review - other |
Reviewed work plan for 130 East Potter Dr. The objective of the work is to delineate the extent of soil contamination detected during Phase II sampling and remove an area of contamination that exceeds health based cleanup levels. Five soil borings will be advanced in the area of contamination in the southwestern portion of the property to delineate the horizontal extent of contamination. Borings will be advanced into the top 12 inches of a suspected clay confining layer to evaluate the vertical extent. An area with benzo(a)pyrene above the health based cleanup level will be excavated and the contaminated soil will be transported to ASR for disposal. Confirmation samples will be collected from the limits of the excavation. |
Bill O'Connell |
| 8/9/2017 |
Document, Report, or Work plan Review - other |
Reviewed Work Plan for Contaminated Soil Excavation at 130 Potter Drive. Previous site characterization efforts documented the presence of petroleum constituents at concentrations exceeding health-based cleanup levels. Approximately 2-3 yards of contaminated soil will be excavated from the impacted area, followed by field screening and confirmation sampling of the excavation. Excavated soil will be staged for offsite disposal pending analytical results. |
Bill O'Connell |
| 5/16/2018 |
Document, Report, or Work plan Review - other |
The ADEC has reviewed "Additional Phase II Environmental Site Assessment and Limited Remediation Activities 130 East Potter Drive Anchorage, AK". Field work was completed in June and August 2017 to delineate and remediate the site.
In June 2017 Nine analytical soil samples plus one duplicate were collected from five soil borings positioned to define the extent of contamination. Sample SB15-2 exhibited concentrations of DRO at 1,220 mg/kg below Method 2 ingestion/inhalation levels, as well as RRO at 11,600 mg/kg below Method 2 inhalation levels but exceeding Method 2 ingestion levels. Sample SB-16-2 and SB16-3 (duplicate) contained DRO below method 2 ingestion/inhalation cleanup levels and RRO below inhalation levels, but above ingestion levels. SB-16-2 and SB16-3 also exceeded ADEC Method 2 ADEC Human Health cleanup criteria for 1,2,4-trimethylbenzene, 1,3,5-trimethylbenzene, benzene, ethylbenzene, toluene and total xylenes. Soil was excavated and removed in the area of SB10 (identified in the phase I)and following the removal analytical soil samples were collected from the base and sidewalls of the excavation. Based on the data in the Phase I assessment samples were only analyzed for benzo[a]pyrene, and all samples collected were below the ADEC Method 2 Human Health level of 0.20 mg/kg.
In August soil was excavated and removed from the vicinity around SB16. Upon completion of the excavation eight analytical soil samples (plus two duplicates) were collected. RRO was detected in samples E1 and N1 at 60,200 mg/kg, and 73,500 mg/kg respectively which exceeds ADEC maximum allowable concentrations. Sample S1 and S2 also contained RRO up to 13,300 mg/kg which exceeds ADEC Method 2 ingestion levels, and Benzene at 52.500 mg/kg which exceeds Method 2 Human Health cleanup levels. Additionally sample W1 contained RRO at 12,200 mg/kg which exceeds Method 2 ingestion levels.
All of the soil excavated from the site was placed into supersacks for analytical results, then transported to Alaska Soil Recycling with ADEC approval. |
Chelsy Passmore |
| 10/15/2018 |
Document, Report, or Work plan Review - other |
The ADEC has reviewed the revisions and additional information provided in the “Work Plan for Excavation of Contaminated Soil; 130 East Potter Drive, Anchorage, AK”. The ADEC has no objections to the work plan. |
Chelsy Passmore |
| 1/17/2019 |
Meeting or Teleconference Held |
The ADEC met with Paragon Professional Services, and BGES (consultant). Biogenic interference, the open excavation, and site closure evaluation were discussed. |
Chelsy Passmore |
| 8/12/2019 |
Document, Report, or Work plan Review - other |
The ADEC has reviewed the February 2019 "Site Remediation Activities" Report for the 130 E Potter Dr site in Anchorage, AK, and issued comments to the consultant. Excavation occurred around soil boring SB5, SB15, and SB16. A total of 76.23 tons of contaminated soil were taken to ASR for thermal treatment. |
Chelsy Passmore |
| 8/12/2019 |
Document, Report, or Work plan Review - other |
The ADEC has reviewed the February 2019 "Site Remediation Activities" Report for the 130 E Potter Dr site in Anchorage, AK, and issued comments to the consultant. Excavation occurred around soil boring SB5, SB15, and SB16. A total of 76.23 tons of contaminated soil were taken to ASR for thermal treatment. |
Chelsy Passmore |
| 11/10/2020 |
Cleanup Complete Determination Issued |
DEC sent a letter closing this site. BTEX and DRO remain in soil to depths of 4.5 feet below ground surface below levels protective of human health. A clay layer was shown to be prevent migration of the contaminants to groundwater. |
Janice Wiegers |
