15 November 2018
From 1881 to 2018, History and Remediation of a Coal Gas Plant, Charlestown, West Virginia
Mr. Joseph Foglio, CHMM, Principal & Senior Vice President, GZA Environmental, Inc.
Between 1881 and 1953 a Manufactured Gas Plant (MGP) operated along the Evetts Run Creek in rural Charles Town, West Virginia, with its most recent operations under the Supertane Gas Corporation. The former Supertane MGP used coal to produce gas that was then distributed to city customers via subsurface gas lines. Although manufacturing operations ended at the MGP in 1953, former structures, including a gas holder, relief holder, gas producer and coke shed were not demolished and remained onsite until the 1990s. The property was purchased by a private landowner for a few thousand dollars to block the construction of apartments and ultimately donated to the City for construction of a park. The former MGP is situated within a residential area and bounded on two sides by the Evitts Run Creek that flowed along its western property boundary and a heavily wooded hillside to the south.
The City of Charles Town uncovered a black tar-like material in soil in 1988 while installing a sewer liner near the property. Subsequent soil sampling conducted by the West Virginia Department of Natural Resources identified a significant amount of residual coal tar and MGP-related byproducts in the soils and shallow groundwater at the Site. Contaminants of concern include polycyclic aromatic hydrocarbons (PAHs) and benzene, toluene, ethylbenzene and xylenes (BTEX). Initial remedial efforts conducted between 1990 and early 2000s by GeoTrans, Inc. included the demolition and removal of former structures, the removal of approximately 2,000 cubic yards of soil and sludge, and the treatment of approximately 17,000 gallons of impacted water from within the gas holder which was subsequently discharged into Evitts Run Creek.
The Environmental Protection Agency (EPA) and the West Virginia Department of Environmental Protection (WVDEP) determined the Site did not qualify for listing on the National Priorities List; however, it was requested by the EPA that additional Site investigation occur. Site investigations completed throughout the 2000s resulted in the identification of additional portions of the Site with soil containing PAHs and BTEX above the WV de Minimis Standards for Residential Land Use and Migration to Groundwater criteria standards on the Site and adjoining properties. Sediment samples collected form the Evitts Run Creek also indicated the presence of PAHs.
GZA became involved with the remediation of the former Supertane MGP Site in 2015 when contacted by the City’s current environmental consultant, Environmental Resources Consulting (ERC) to assist with the design to remediate the remaining impacted soil at the Site. ERC had secured funding through the EPA’s Revolving Loan Fund (RLF) and mandatory contributions from the City and former property owner to implement the remedy. The town had huge aspirations for the property, including construction of a combination basketball court ice skating rink, walking paths linked to a cross-County multi-modal trail system, elevated boardwalk along the creek, an amphitheater nestled into the hillside, and a parking lot over the capped site. The budget: an unclear number between $500,000 and $750,000. GZA diligently worked to understand the nature and extent of contamination on the Site the true needs of the City versus the dreams of an overzealous community planner to develop a remedial design that would provide a long-term, cost effective solution for the community. Through a series of redesigns and competitive bidding, we were able to deliver a multi-layer geosynthetic cap over the former MGP, green space for community gatherings and pickup games of soccer (a community favorite) with picturesque views of Evitts Run, rain garden to manage runoff from the property, grading to accommodate future trails, and a parking lot.
Our presentation will provide a brief overview of the project and focus on the challenges GZA overcame following bidding of the remedial activities through completion of construction. GZA served as the Construction Manager as Agent for the City and was responsible for developing lower cost solutions to completion of the work; managing an overwhelmed contractor’s construction sequence and methods, schedule and budget; and ensure that it all came together in time for a high-profile ribbon cutting ceremony fit for Presidential-appointed EPA officials.