Environmental Restoration

Environmental Services and NPL Program Support, Former Fort Ord, CA
U.S. Army Corps of Engineers, Sacramento

The former Fort Ord facility is listed as a National Priority List (NPL/Superfund) site and includes areas that are subject to the Base Realignment and Closure (BRAC) process. AGSC is providing a variety of environmental restoration services as part of the cleanup activities at the facility.

To date, AGSC has performed two in-situ pilot studies for use of innovative technologies for enhancement of groundwater treatment, including chemical oxidation and enhanced reductive dechlorination (ERD). Other AGSC services have included design/build upgrades to three groundwater treatment systems, building demolition, asbestos and lead-based paint abatement. In addition, AGSC organizes and supports the public outreach program for the prescribed burn program, SMART Team activities, community involvement workshops, and other activities associated with the ordnance and explosive waste (OEW) and Superfund remediation programs.

Landfill Cap Design and Construction, Naval Air Station, South Weymouth, MA
Engineering Field Activity Northeast

AGSC designed and constructed two landfill caps for the rubble disposal area and the West Gate Landfill at the Navy base. In each case, AGSC’s design activities included scientific modeling for both gas management layer and flood plain analyses to minimize erosion and meet regulatory requirements. Following design approval, AGSC’s crews set to constructing the caps, installing gas management systems and placing clean fill and cover material to required thicknesses. Prior to constructing the rubble disposal area cap, AGSC performed a soil investigation for PCB contamination and removed soil from the areas determined to be contaminated. In addition, AGSC restored wetland areas in the vicinity of the newly constructed cap.

Excavation and Thermal Treatment, Cold Bay, AK
U.S. Air Force

Known as the "Gateway to the Aleutians," Cold Bay is located on the western end of the Alaska Peninsula, approximately 600 miles southwest of Anchorage, AK. AGSC was contracted to perform excavation, stockpiling, and thermal treatment of diesel-contaminated soil at the former tank farm site. Due to the remote site location, unique logistical problems had to be overcome; equipment was mobilized on a barge, while personnel and supplies traveled on commercial aircraft. In addition, harsh winter conditions required the project to be broken into two phases.

The first phase was conducted during the warm summer months and consisted of excavation of fuel-contaminated soil, which was stored in long-term stockpiles for winter storage. Extensive sampling was conducted as a baseline for long-term storage. The second phase was thermal treatment of the stockpiled soil and was conducted in the middle of winter. AGSC continuously sampled the stockpiled soil during treatment to verify removal met regulatory cleanup levels, then the certified-clean soil was returned as fill, prior to site restoration.

Demolition

Abatement and Demolition, Stilwell Hall South Wing, Former Fort Ord, CA
U.S. Army Corps of Engineers, Sacramento

When the abandoned 50,000-square-foot former Officers' Club was undermined by beach erosion, AGSC was called upon to help prevent the historic building from falling into the Pacific Ocean. The building contained extensive amounts of asbestos and lead-based paint, which had to be abated before demolition. As a result, the project was broken into two phases: the first being the abatement and the second, removal of the building. Within 24 hours, AGSC had mobilized and began to inventory and remove historic artifacts and cordon off areas of endangered plant species. Complete demolition followed phase 1 abatement activities, taking care to prevent objects from falling over the 150-foot cliff into the ocean. All work had to be competed quickly due to the endangered plant and animal species in the area.

Demolition and Environmental Cleanup, Cape Sabine, AK
Tetra Tech FW/U.S. Navy

Located on the remote shore of northwestern Alaska, Cap Sabine was once a fully manned Early Warning Detection (EWD) Radar Site during the Cold War. The site was decommissioned in the 1960s and was put on the list for demolition. AGSC carefully performed demolition of buildings, tanks, and towers taking care not to damage the sensitive Alaskan tundra. In addition, several areas with petroleum and PCB-contaminated soils were excavated and restored to original condition. Complicating the situation were daily visits to the camp by bears, which had to be deterred by an electric fence. Despite high winds, snow, rain, and fog, the AGSC crew completed the project on time, with no safety incidents. Final comments from the Alaska Bureau of Land Management stated that the site was one of the finest EWD site restorations that they had seen.

Demolition and Environmental Remediation, Point McIntyre, AK
Tetra Tech FW/U.S. Navy

Point McIntyre is located on the Arctic Ocean, 15 miles northwest of Prudhoe Bay, and served as one of the U.S. Navy’s Defense Early Warning (DEW) Line sites before operations ceased in the 1960s. As part of a larger remedial action effort, AGSC was called to assist in decommissioning and cleanup of the abandoned DEW Line facility. Work was conducted in two phases to accommodate the extreme weather and logistical conditions ever present in the Arctic. The first phase was performed during the late winter months and consisted of demolition and initial debris removal. The work was conducted in harsh conditions with temperatures dipping below -40 degrees. Due to the extreme cold, the site could only be accessed by land via an ice road. A small crew was then mobilized via helicopter in late summer to remove waste and debris that were hidden by the thick layer of snow.

Groundwater Treatment System O&M

Operation & Maintenance of Groundwater Treatment Systems, Former Ft. Ord, CA
U.S. Army Corps of Engineers, Sacramento

AGSC is performing O&M services at three groundwater treatment plants (GWTP) for treatment of VOC-impacted groundwater using granular activated carbon (GAC) at a cumulative flow rate of approximately 1,000 gpm. AGSC’s O&M team performs sampling and analysis, QA performance evaluations, data validation, database management, and reporting. Periodically the team evaluates the data to make adjustments, ensuring that the system is operating at optimum levels, ensuring cleanup goals are met. AGSC is also responsible for developing a ramp-down strategy for the operation of the plant, delisting the site from the National Priority List (NPL), and supporting eventual closure of the facility upon attainment of the remediation goals identified in the Record of Decision (ROD).

GWTP O&M, Riverbank Army Ammunition Plant, CA
US Army Corps of Engineers, Sacramento/Army Environmental Command

AGSC is responsible for O&M of three GWTPs (OU1, OU2, and Sites 2/12) for treatment of VOC-impacted groundwater under a performance-based contract. AGSC provides a full-time plant operator who performs routine O&M activities, including GAC changeouts, flow management and water level monitoring, effluent and extraction well sampling and analysis, and data management. In order to ensure successful achievement of performance0based objectives, AGSC continually evaluates sample data for potential opportunities for system optimization.