Adak Update

A view of Downtown Adak, overlooking Sweeper Cove

CERCLA, RCRA, and Petroleum Site Engineering Controls

Engineering controls encompass a variety of engineered remedies to contain or reduce contamination, or physical barriers intended to limit access to property. Engineering controls, as they relate to Adak Island, include fences, signs, caps or barriers, and treatment systems including monitoring wells. The engineering controls identified in the OU A ROD, petroleum cleanup sites, and those that will apply as interim measures to OU B are described below.

Under the OU A ROD signed in 2000, fishing advisory signs were posted for subsistence fishers because of low levels of PCBs detected in bottom fish (rock sole) and shellfish (blue mussels) of Sweeper Cove and Kuluk Bay. The OU A ROD Amendment removes the requirement for fish advisory signs. Instead, the Navy will provide an information pamphlet to the residents of the City of Adak, because they are the most likely people to eat locally caught fish and shellfish as part of a subsistence diet. Fish information pamphlets will be updated as new information is collected and trends are analyzed. Copies of the updated pamphlets will be put in residence mail boxes, and copies will be placed at the City of Adak and U.S. Fish and Wildlife offices. The consumption of rock sole or blue mussels by recreational fishers poses no unacceptable health risks.

Ordnance hazard signs are in place on fencing around the part of the perimeter of the access restricted area adjacent to Lake Andrew. As of the end of the 2002 field season, remediation has been completed on all areas outside the access-restricted area adjacent to Lake Andrew. For this reason, with the exception of the signs at the perimeter of the Lake Andrew area, these signs are no longer required and were removed in 2003. Fences and gates at the access-restricted areas adjacent to Lake Andrew will be retained and maintained until the OU B-2 ROD is executed. Thereafter, ICs and ECs will be subject to the terms of the OU B-2 ROD.

Other engineering controls/remedies listed in the Comprehensive Monitoring Plan, Revision 1 are listed below.

Excavation and treatment by thermal desorption of contaminated sediments and soils and recycling of treated sediment and soils as cover material at Roberts Landfill;
Placement of a soil cover on one non-landfill site;
Recycling of treated soils from CERCLA sites as cover material at Roberts Landfill;
Monitoring groundwater at CERCLA sites for volatile compounds and semivolatile compounds;
Removal and treatment of petroleum-contaminated soils to meet State of Alaska cleanup requirements;
Monitored natural attenuation of petroleum chemicals in soil and groundwater;
Free-product recovery to the maximum extent practicable as an interim remedial measure, followed by final remediation to achieve cleanup levels under State of Alaska requirements for soils and groundwater; and
Maintenance of an UXO Awareness educational program for on-island residents and visitors.