FAIRMONT, W.Va. (AP) — Three companies will pay nearly $30 million to continue cleaning up a riverside Superfund site near Fairmont and to reimburse the state and federal governments for previous work, the U.S. Environmental Protection Agency announced Monday.

The settlement filed in U.S. District Court in Clarksburg requires Exxon Mobil Corp., Vertellus Specialties Inc., and CBS Corp., to spend $17.8 million cleaning up the mess that their predecessor companies created decades ago while processing coal tar and other hazardous wastes.

The reimbursements total about $11 million, the EPA said, while costs going forward are projected to be another $1 million.

The 38-acre property along the Monongahela River was designated a Superfund site in 2000, decades after industrial activity dating to 1932 polluted it with coal tar, light bulb byproducts and other hazardous materials.

The cleanup will include removing about 5,500 cubic yards of tainted soil, building an impermeable cap and improving a groundwater containment system to keep the hazardous materials from migrating.

Between 1932 and 1973, the site was a tar processing and refining plant owned by a predecessor of Vertellus Specialties, including Reilly Tar and Chemical Corp.

Domestic Coke, a predecessor of ExxonMobil, ran a coke product plant next to the site, delivering the crude tar for processing along with the former Sharon Steel Corp.

From 1973 to 1984, Big John Salvage owned the property and ran a metal, glass, and oil salvaging operation.

EPA officials say Big John's took hazardous waste from Westinghouse Electric Co., a predecessor of today's CBS Corp., and that waste included lead dust, mercury-tainted waste oil and fluorescent light bulbs that contained mercury.

The court filing says Big John's filed for bankruptcy in 1984.

Work to keep tar from seeping into surface water and the Monongahela River has been under way for years.

Since Big John's was labeled a Superfund site, the regulatory agencies have been able captured more than 11 million gallons of tainted water, cleaning it in a series of treatment systems before it can enter the river.