Superfund Record of Decision (EPA Region 6): Motco Superfund Site, La Marque, Texas (Second Remedial Action), September 1989

摘要

The 11-acre Motco site is in La Marque, Galveston County, Texas. Pits were used by a styrene tar recycling business which operated from 1959 to 1961, and by an industrial chemical waste disposal facility from 1961 to 1968. In 1984 an initial remedial measure (IRM) was conducted by EPA and included removal and offsite disposal of wastes from nine above ground storage tanks. The first operable unit for the site was issued in 1985 and dealt with source control measures including excavation of the onsite waste pits, which contained 12 million gallons of contaminated water and organic liquids, down to the sludge/soil interface plus one foot, and incineration of those wastes. The Record of Decision represents the second and final operable unit, management of migration, for the site and addresses the subsurface beneath the waste pits and offsite contamination of the ground water, soil, and sediment. Ground water at the site is found in a Transmissive Zone and the underlying Upper Chicot aquifer. The primary contaminants of concern affecting the soil, sediment, and ground water are VOCs including benzene; other organics including PAHs; and metals including arsenic, chromium, and lead.