Site Report: ConocoPhillips Itkillik River Unit #1 (ARCO)
| Site Name: | ConocoPhillips Itkillik River Unit #1 (ARCO) |
|---|---|
| Address: | 7.5 Mi. Up Itkillik River, from Colville River Confl, Nuiqsut, AK 99789 |
| File Number: | 300.38.081 |
| Hazard ID: | 2362 |
| Status: | Cleanup Complete - Institutional Controls |
| Staff: | IC Unit, 9074655229 dec.icunit@alaska.gov |
| Latitude: | 70.116389 |
| Longitude: | -150.148056 |
| Horizontal Datum: |
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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
It was reported that diesel fuel was seeping out of an abandoned drill pad. Tundra has been impacted adjacent to the pad. Previous site assessments indicate that one or more diesel spills occurred on the gravel pad in the mid-1970s. Soil samples collected from the pad, runway, and tundra surrounding the pad, were analyzed for diesel range organics (DRO), polynuclear aromatic hydrocarbons (PAHs), and benzene, toluene, ethylbenzene, and xylenes (BTEX). The most recent investigation (CH2M-HILL September 2003) focused on characterizing and defining the extent of DRO contamination on the gravel pad and tundra. The following activities were conducted during April 2004 and documented in the Final Cleanup Report. -Survey and stake locations and elevations of borings, stained areas and solid waste debris, -Excavation of six stained areas on the gravel pad , -Collection and removal of plastic and metal debris for off-site disposal, -Excavation, and stockpiling of soil from the area of known contamination on the west side of the pad in the vicinity of borings IRB-13 and IRB-15, -Screen and sample stockpiles, -Backfill and regrade excavated areas, -Transportation of contaminated soil to Deadhorse for thermal remediation during the summer of 2004.
Action Information
| Action Date | Action | Description | DEC Staff |
|---|---|---|---|
| 12/28/1994 | Site Characterization Report Approved | (Old R:Base Action Code = SA2R - Phase II SA Review (CS)). Site assessment report prepared 5/20/94 and reviewed by ADEC on 12/28/94. | Scott Rose |
| 1/5/1995 | Site Added to Database | Site added to database. | Scott Rose |
| 11/12/2002 | Update or Other Action | BP Charter Site - Conoco Phillips assuming responsibility for CU. Meeting on this day to discuss site. Pnillips has found a potential RP for this contamination, and will pursue RP to contribute to CU scheduled for winter 2003. This may delay CU until winter of 2004. | Linda Nuechterlein |
| 4/25/2003 | Update or Other Action | The historic information indicated ARCO vacated the site in early 1970's and there were no environmental issues. Wetern Geophysical used the site in 1975 and in subsequent years. A potentially responsible party letter was sent to Western Geco for additional information. | Jim Frechione |
| 2/11/2004 | Cleanup Plan Approved | Cleanup plan prepared by CH2MHill proposes excavation of hot spot areas on the pad, and offsite treatment either at DS 1H and/or Deadhorse. CPAI proposes a target cleanup level of 2000 mg/kg DRO. Previous assessments have identified 3 areas with greater than 2000 ppm DRO. | Linda Nuechterlein |
| 5/25/2004 | Update or Other Action | Received Final CU Report from Conoco Philips. The following activities were conducted during April 2004: -Survey and stake locations and elevations of borings, stained areas and solid waste debris, -Excavation of six stained areas on the gravel pad , -Collection and removal of plastic and metal debris for off-site disposal, -Excavation, and stockpiling of soil from the area of known contamination on the west side of the pad in the vicinity of borings IRB-13 and IRB-15, -Screen and sample stockpiles, -Backfill and regrade excavated areas, -Transportation of contaminated soil to Deadhorse for thermal remediation during the summer of 2004. | Linda Nuechterlein |
| 8/11/2004 | Update or Other Action | Approval given to transport & dispose of 800 cubic yards of thermally treated gravel. Arctic Fox Environmental sampled & submitted post treatment results. | Linda Nuechterlein |
| 1/26/2005 | Conditional Closure Approved | A NFRAP letter was sent to the RP (ConocoPhillips) to document that cleanup actions to date have served to excavate and remove contaminated soil from areas in close proximity to the Itkilik River. There are other areas at the Itkilik site that have elevated levels of petroleum hydrocarbons remaining but they do not currently pose a risk to human health or the environment. Based on this information, DEC has determined that no further remedial action is required for the Itkillik River Unit #1 pad. An institutional control will be recorded in the Department’s CS database to identify areas on the pad where hazardous substance contamination above the Methos Two Migration to GW level may remain. This site will be removed from the North Slope Existing CS D-2 list. | Linda Nuechterlein |
| 1/26/2005 | Institutional Control Record Established | An institutional control is recorded in this db to identify the following areas on the pad where hazardous substance contamination remains above the target cleanup level of 2000 mg/kg DRO. -Contaminated gravel in the vicinity of Boring ARB 960 with 8300 mg/kg DRO. -Contaminated gravel around Boring IRB-5 with 6780 mg/kg DRO. - contaminated soil above the target level of 2000 mg/kg DRO was identified in four tundra areas south of the pad that did not sheen. It was decided not to excavate these areas since excavation may cause more damage to the tundra than benefit. -Any proposal to transport soil off site requires DEC approval in accordance with 18 AAC 75.325(i). | Linda Nuechterlein |
| 4/4/2012 | Institutional Control Compliance Review | IC review conducted and staff name changed from Nuechterlein to IC Unit. | Evonne Reese |
| 12/4/2014 | Update or Other Action | Staff name changed from IC Unit to McLoone | Evonne Reese |
| 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 |
| 2/1/2021 | Institutional Control Compliance Review | IC compliance review started. A combined IC verification letter will be issued to ConocoPhillips early this year. | Evonne Reese |
| 5/30/2024 | Institutional Control Compliance Review | IC compliance review completed on this date. An IC reminder letter was e-mailed to the landowner. The next review will be in five years’ time. | Gaige Robinson |
| 12/2/2024 | 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 |
Control Type
| Type | Details |
|---|---|
| CS Database Notation And Letter To Landowner/RP |
Requirements
| Description | Details |
|---|---|
| Excavation / Soil Movement Restrictions | |
| Advance approval required to transport soil or groundwater off-site. | Any proposal to transport soil off site requires DEC approval in accordance with 18 AAC 75.325(i). |
| When Contaminated Soil is Accessible, Remediation Should Occur |
No associated sites were found.