Project Merit: Remediation


CH2M HILL (Denver, CO) for safely destroying 145 WW II mustard gas projectiles at a former military depot in Columboola, Australia. Overpack containers on the munitions at the Columboola depot reduced storage danger but made the munitions difficult to destroy. CH2M HILL used its patented TC60 transportable detonation chamber (TDC) technology, which increases the safety of chemical-agent munitions destruction by reducing handling and preventing public exposure to dangerous munitions. With the portable system, which includes a destruction chamber and an air pollution control system to treat discharged gases, chemical munitions can be destroyed on site rather than being transported on public roadways for off-site treatment. CH2M HILL supported the Australian Department of Defence with ongoing public information, and the project was recognized at a local environmental education center in 2012.

Engineering/Remediation Resources Group, Inc. (ERRG; (Martinez, CA) for its work in restoring an abandoned copper mine in the remote Rogue River-Siskiyou National Forest, where waste rock was leaching sulfuric acid, arsenic, lead, cadmium, copper, and zinc were seeping into nearby creeks for 100 years. The Blue Ledge Mine Remediation was a large, complex environmental project where access, terrain, and logistics created significant challenges. The project, performed for the U.S. Forest Service, included removing 65,000 cubic yards of waste rock, encapsulating it in a geomembrane-lined repository, reclaiming the 22 acres of disturbed areas, installing erosion control measures, replacing topsoil, and restoring native vegetation with over 15,000 native plants that were grown in an off-site nursery. A unique aspect of the project involved the use of three Spider excavators to crawl up the steep slope of the mountainside. The tailings were pulled down to where they could be handled with larger earth-moving equipment. Reinforced slope stability fabric was installed, and sediment and pH treatment basins were constructed. In addition, road access was not available to three of the four waste rock areas, so ERRG constructed approximately one mile of roads through rugged terrain to provide access to the areas.

Coastal Environmental Group (Edgewood, NY) for its work on the Dalbey Bottom Chutes Phase II contract with U.S. Army Corps of Engineers Kansas City District. This challenging low-land project faced constant flooding by the Missouri River, substantial amounts of groundwater inside the excavations, the extremes of working 24 hours a day through the winter, and unstable ground. The project involved the excavation of over 1.7 million cubic yards of contaminated soil, making it the largest Chute project undertaken by the Corps to date. Excavation started on December 26, 2011, and continued through to substantial completion on August 25, 2012, over 2.5 months ahead of the seeding-window schedule and nearly four months prior to originally scheduled contract completion date. Coastal currently holds nine Multiple Task Order Award Contracts (MATOCs) with the Corps' Kansas City, Baltimore, Omaha, and Galveston offices, the U.S. Fish and Wildlife Services, and the New York National Guard Bureau, totaling in $488.6 million in capacity.

SCS Engineers (San Diego, CA) for its implementation of the cleanup and an innovative soil reuse plan at the Mercado del Barrio site in San Diego County. The Mercado Del Barrio project encompasses the redevelopment of seven acres of San Diego's Barrio Logan community into a revitalized affordable housing site that includes a Latino-centric grocery store, commercial and restaurant space, affordable housing, and above-ground parking. SCS Engineers was contracted to provide environmental consulting and construction services for the project. SCS's site assessment found that the upper one to five-plus feet of soil across the site had concentrations of lead high enough to necessitate the disposal of approximately 23,000 cubic yards of soil at landfills. This would have cost the project approximately $2 million, which was not affordable. In addition, the off-site disposal of 37,000 tons of lead-impacted soil would have required more than 1,600 truck trips, resulting in approximately 350,000 miles driven by diesel-fueled trucks. To avoid these impacts, SCS designed a plan to bury or "reuse" the impacted soil beneath the parking and commercial spaces and cap it with six to nine feet of clean soil. The design took into consideration future landscape and utility maintenance needs.