A cost-effective, endpoint-focused strategic approach was used to remediate coal tar at a former sand and gravel pit under Maine's Voluntary Response Action Plan (VRAP) Program. Pre-excavation sampling for PAH and TCLP parameters indicated that coal-tar affected soils containing PAH concentrations up to 11,000 parts per million were non-hazardous, and provided data that supported the following: 1) permit modifications for recycling facilities, including an asphalt-batch plant and a cement kiln, to accept MGP wastes for the first time in Maine; 2) direct loading of affected soils into trucks during excavation, eliminating the need for stockpiling pending results of post-excavation characterization; 3) the use of visual criteria to determine the limits of excavation during remediation; 4) refinement of the volume estimate of material to be excavated; and 5) successful planning and coordination of fast-track remedial construction. Risk-based cleanup levels for PAH were derived based on restricted future site use, and post-excavation confirmation samples showed that remaining PAW concentrations were 3 orders of magnitude lower than site-specific cleanup levels. Excavation and recycling were performed in adverse weather conditions from late November 1995 through January 1996. More than 30,000 tons of affected soils were recycled into cold-mix asphalt product, and a 500-ton trial burn was performed at a cement kiln. Excavation and recycling were completed in a little over two months, while the entire project, including development of a strategic approach, investigation and cleanup plan preparation, state and town agency review and approval, pre-excavation sampling and analysis, and cleanup, was completed in seven months. The cost of performing work under the voluntary cleanup program was approximately one-seventh of the cost estimated to perform the work under traditional enforcement programs. The keys to success were the close cooperation of the project team and regulators, and the commitment of all stakeholders to the goal of site closure using good science and engineering methods.
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