| Action Date |
Action |
Description |
DEC Staff |
| 7/8/2014 |
Site Added to Database |
A new site has been added to the database |
Mitzi Read |
| 7/8/2014 |
Document, Report, or Work plan Review - other |
On this day the Alaska Department of Environmental Conservation (ADEC) Contaminated Sites Program (CSP) reviewed the Above Ground Storage Tank Containments report from Environmental Management Incorporated (EMI), dated January 28, 2014. The report documented an investigation of two former above ground storage tanks (ASTs) containment areas; named Cont1 and Cont2. Investigation of the two containments was performed in September of 2013. Cont1 was roughly 60 square feet in size and Cont2 was approximately 800 square feet in size; both containments had 4 to 5 feet high berms. Several surface soil samples [collected from between 6 and 12 inches below ground surface (bgs)] were collected from beneath the liner in both Cont1 and Cont2. Concentrations of diesel range organics (DRO) were present in both containment areas and ranged from 785 mg/kg to 25,400 mg/kg; all of which exceed the ADEC Method One cleanup level, as outlined in 18 AAC 75.341 (b), Table A2. |
Joshua Barsis |
| 7/8/2014 |
Exposure Tracking Model Ranking |
Initial ranking with ETM completed for source area id: 79644 name: Diesel ASTs & Containment Area |
Joshua Barsis |
| 7/17/2014 |
Potentially Responsible Party/State Interest Letter |
Letter of state interest sent on this day. |
Joshua Barsis |
| 7/28/2014 |
Document, Report, or Work plan Review - other |
CSP reviewed and approved the Draft Work Plan for Soil Removal at Above Ground Storage Tanks Containment Area. |
Joshua Barsis |
| 11/5/2014 |
Document, Report, or Work plan Review - other |
CSP received the “Soil Removal at Containment Area 1 and Follow-on Sampling at Containment Area 2” report from CH2M Hill on this day. The report documented excavation activities at containment area 1 and further characterization at containment area 2. Pad pore water was encountered during the containment 1 excavation at roughly 4 feet bgs, and limited the depth of excavation. Analytical results revealed that DRO, GRO, benzene, toluene, ethylbenzene, and xylenes remain in the subsurface soils at containment area 1 up to 3,600 mg/kg, 2,700 mg/kg, 1.4 mg/kg, 28 mg/kg, 17 mg/kg, and 220 mg/kg, respectively. DRO remains in the surface soils at containment area 2 up to 2,400 mg/kg. Containment area 2 was not excavated. |
Joshua Barsis |
| 11/20/2014 |
Exposure Tracking Model Ranking |
Initial ranking with ETM completed for source area id: 79701 name: Containment Area 2 |
Joshua Barsis |
| 11/20/2014 |
Exposure Tracking Model Ranking |
A new updated ranking with ETM has been completed for source area 79644 Containment Area 1. |
Joshua Barsis |
| 2/27/2015 |
Update or Other Action |
Letter sent indicating that additional delineation is required. |
Joshua Barsis |
| 4/15/2015 |
Site Characterization Workplan Approved |
Reviewed the Containment Area 1 Follow-on Soil Sampling Work Plan, dated April 2015. Activities outlined in the work plan include advancing soil borings and collecting additional soil samples to delineate contamination at Containment Area 1. |
Joshua Barsis |
| 12/1/2015 |
Document, Report, or Work plan Review - other |
Reviewed the report titled Follow-on Soil Sampling at Containment Area 1, dated October 2015. In August of 2015, a total of 21 soil borings were advanced around the perimeter of Containment Area 1 in an effort to delineate the lateral and vertical extent of contamination. Soil samples were collected from the active layer in each boring. Results of the investigation indicate that contamination is not migrating to the north, west, or east. Contamination was not fully delineated to the south or southeast, as evident by Samples SB10 and SB10-B. Sample SB10-B exhibited concentrations of DRO and GRO at 1,800 mg/kg and 150 mg/kg, respectively, both of which exceed Method One soil cleanup levels. In a letter dated 11-30-2015 ADEC requested further delineation of Containment Area 1 and Containment Area 2. |
Joshua Barsis |
| 5/3/2016 |
Document, Report, or Work plan Review - other |
Reviewed the Containment Area 1 and Containment Area 2 Follow-on Soil Sampling Work Plan, dated May 2016. The work plan proposes to collect soil samples, and potentially suprapermafrost groundwater samples from several soil borings advanced at Containment Areas 1 and 2. |
Joshua Barsis |
| 1/4/2017 |
Document, Report, or Work plan Review - other |
Reviewed the report titled Follow-on Soil Sampling at Containment Area 1 and Containment Area 2, dated for December 2016. Field activities were completed on July 14 and 15, 2016 and primarily consisted of collecting soil samples from 24 soil borings advanced at the site. Results from the investigation revealed that the vertical and horizontal extent of contamination in the soil has been generally delineated.
One water sample was collected from the base of Boring 18, where water was observed and a sheen was noted. Volatile constituents detected in the water sample exceeded the vapor intrusion (VI) target levels for groundwater. Because of the proximity of groundwater contamination to the Green Service Bays Building and the Beige Building, and because of the depth of groundwater, ADEC requested that the potential for VI exposure be evaluated, or that a work plan be submitted (if sampling is necessary) by May 1, 2017.
|
Joshua Barsis |
| 6/28/2017 |
Document, Report, or Work plan Review - other |
Reviewed the report titled Evaluation of Vapor Intrusion Pathway at Containment Area 1 in Deadhorse, dated June 28, 2017. This evaluation was completed to assess the vapor intrusion pathway at the Beige Building and the Green Service Bays Building, both of which are in close proximity to the porewater sample collected from Boring SB18 in 2016. Site-specific porewater target levels were calculated using the EPA Johnson and Ettinger Vapor Intrusion Model. The VI exposure pathway at Containment Area 1 is considered de-minimis and this site will be evaluated for closure in fall/winter 2017. |
Joshua Barsis |
| 3/29/2020 |
Cleanup Complete Determination Issued |
Cleanup complete issued on 3/31/2020. |
Joshua Barsis |
| 3/29/2020 |
Exposure Tracking Model Ranking |
A new updated ranking with ETM has been completed for source area 79644 Containment Area 1. |
Joshua Barsis |
| 3/29/2020 |
Exposure Tracking Model Ranking |
A new updated ranking with ETM has been completed for source area 79701 Containment Area 2. |
Joshua Barsis |
