Site Report: Hilcorp NS South Hangar Pad (BPX)
| Site Name: | Hilcorp NS South Hangar Pad (BPX) |
|---|---|
| Address: | ~4.5 Mi NE of Deadhorse Airport, Prudhoe Bay, AK 99734 |
| File Number: | 300.38.271 |
| Hazard ID: | 4594 |
| Status: | Cleanup Complete - Institutional Controls |
| Staff: | IC Unit, 9074655229 dec.icunit@alaska.gov |
| Latitude: | 70.248679 |
| Longitude: | -148.349605 |
| Horizontal Datum: | NAD83 |
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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
After drilling boreholes for vertical support members to 28 feet, the boreholes became filled with jet fuel, which was encountered at about approximately 18 feet bgs. Site is located adjacent to DSM Shop site. SOurce is suspected to be 1971 jet fuel spill of 45,000 gallons. The 2009 CC with ICs decision was based on this site being considered part of a larger site which includes the Drill Site Maintenance Pad and that contamination that had been associated with the South Hangar Pad site might actually be related to the DSM site.
Action Information
| Action Date | Action | Description | DEC Staff |
|---|---|---|---|
| 2/19/2008 | Site Added to Database | Site added to the database. | Mitzi Read |
| 2/19/2008 | Exposure Tracking Model Ranking | Initial ranking with ETM completed. | Bill O'Connell |
| 3/25/2008 | Update or Other Action | Received Interim Status Report on South Hangar Pad. Product in VSM holes determined to be jet fuel from a previous release and was only found at depths greater than 20 feet bgs Chlorinated compounds were not found in soil at the site. Additional investigation to delineate the extent of contamination is anticipated. | Bill O'Connell |
| 4/2/2008 | Site Characterization Workplan Approved | Site assessment work plan received for South Hangar Pad Tent Site. Boreholes will be drilled in area of known jet fuel contamination in an attempt to delineate the vertical and possibly the horizontal extent of subsurface contamination. A bail down test will be conducted at the existing VSM boreholes to determine connectivity and product recharge. A proposed new tent site will be evaluated using soil borings to see if contaminatiomn is present. Additional investigation will be conducted later in 2008 if more information is needed. | Bill O'Connell |
| 5/26/2009 | Site Characterization Report Approved | Reviewed South Hangar Pad Tent Site Fuel Investigation Report. The presence of free product in the subsurface is attributed to a 45,000 gallon Jet fuel spill in 1971. During this investigation, a baildown test was performed at the VSM holes where product was first identified, nine soil borings were advanced on the gravel pad and seven soil borings were advanced in the surrounding tundra. The bail down test found very poor product recovery at the VSM boreholes, with a recovery rate of approximately 0.002 gallon per day, which is significantly below the feasibility threshold for product recovery. Of the 16 additional boreholes, only one contained free product. Borehole SB-20 located just north of the original tent site contained approximately 5 feet of product after a five day period. Soil samples collected from boreholes found DRO up to 27,500 mg/kg at 18.5 to 20 feet bgs in borehole SB-3, GRO up to 3,240 mg/kg in borehole SB-20, ethylbenzene up to 394 mg/kg at 18-18.5 feet bgfs, and xylenes up to 1,730 mg/kg in the same sample. Generally, hydrocarbon impacts were not found between the base of the pad and the 18-foot depth interval and boreholes advanced in the tundra did not find hydrocarbon impact at all except at borehole SB-8, located adjacent the area of product found at the pad. | Bill O'Connell |
| 5/27/2009 | Exposure Tracking Model Ranking | A new updated ranking with ETM has been completed for source area 75618 Suspected-45,000 gallon jet fuel spill in 1971. | Bill O'Connell |
| 6/10/2009 | Cleanup Complete Determination Issued | The Alaska Department of Environmental Conservation, Contaminated Sites Program (ADEC) has completed a review of the environmental records associated with BPX South Hangar Pad located near Prudhoe Bay, Alaska. 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 as long as the site is in compliance with established institutional controls (ICs). | Bill O'Connell |
| 7/7/2009 | Institutional Control Record Established | Institutional Controls established and entered into the database. | Bill O'Connell |
| 6/13/2012 | Institutional Control Compliance Review | An IC review was conducted on this site, periodic review is not due until 2014, and the staff assigned was changed from Bill O'Connell to IC Unit. | Evonne Reese |
| 7/29/2014 | Institutional Control Update | An IC reminder letter was issued to the responsible party on this date. | Kristin Thompson |
| 11/3/2014 | Update or Other Action | The 2009 CC with ICs decision was based on this site being considered part of a larger site which includes the Drill Site Maintenance Pad and that contamination that had been associated with the South Hangar Pad site might actually be related to the DSM site. | Keather McLoone |
| 9/28/2016 | Update or Other Action | At this time, the project manager chooses to retain management of this site which has institutional controls. | IC Unit |
| 7/9/2024 | Institutional Control Compliance Review | IC compliance review completed on this date. An IC reminder letter was issued to the responsible party and cc’d to the landowner. The next review will be in five years’ time. | Gaige Robinson |
| 8/27/2024 | Institutional Control Compliance Review | The landowner responded to the IC reminder letter and provided a written confirmation that land use has not changed | Gaige Robinson |
Contaminant Information
| Name | Level Description | Media | Comments |
|---|---|---|---|
| DRO | > Method 1 (Arctic only) | Soil | Contamination resides deeper than 18 feet bgs in Arctic Zone |
Control Type
| Type | Details |
|---|---|
| Signed CS Determination |
Requirements
| Description | Details |
|---|---|
| Advance approval required to transport soil or groundwater off-site. |
No associated sites were found.