Midwest Solvent Recovery (Midco I) began industrial waste recycling, storage, and disposal at a site in Gary (Lake County), Indiana, sometime prior to June 1973. A fire occurred at this site on December 21, 1976. After the fire, Midco I operations relocated to a second site in Gary and operated as the Midwest Industrial Waste Disposal Company (Midco II).

In June 1981, severe flooding caused water to drain into a neighborhood of the City of Hammond. Contact with this flood water reportedly caused skin burns which were attributed to drainage from Midco I and the Ninth Avenue Dump, located north of Midco I. From February to July 1982, the United States Environmental Protection Agency (EPA) removed and disposed of hazardous wastes from the Midco I site. The surface contamination had been removed; additional contaminated soil and ground water remediation is ongoing. In December 1982, Midco I was placed on the National Priorities List.

Midco II operations began in January 1977 and included temporary bulk liquid and drum storage of waste and reclaimable materials, neutralization of acids and caustics, and on-site dumping of waste. On August 15, 1977, a fire at Midco II destroyed equipment, buildings, and an estimated 50,000 drums. In 1981, EPA installed a fence around the site. From 1984 to 1986, EPA conducted a removal action, which included fence repair and extension; sampling and removal of drums, tanks, and debris; and removal of the sludge pit and filter bed contents. Midco II was placed on the NPL in October 1984. EPA initiated Remedial Investigations (RI) and Feasibility Studies (FS) in 1985.

The RIs for Midco I and II concluded that the 2 sites are contaminated with metals, cyanide, and a variety of organic compounds in the soil and ground water. Past storage and disposal practices on and near the sites have also resulted in a high level of salt contamination in the ground water under both sites.

Ninth Avenue Dump is a 20-acre site just north of the Midco I facility, separated by approximately 350 yards of palustrine wetland. This area between the two facilities consisted of predominately undisturbed dune and swale habitat prior to 1954. Portions of the site were graded and filled between 1954 and 1973 when waste handling operations began. These operations included drum storage, drum burial, tanker truck storage, and disposal of bulk liquid wastes into excavated areas. Wastes accepted at this facility included: oil, paint solvents, sludges, resins, acids, and construction debris. An inspection in 1975 revealed over 10,000 drums were stored on-site. In 1980, over 500 deteriorating drum and 6 abandoned tanker trucks were still on-site.

In 1985, EPA recommended that a RI/FS be initiated at this site. Contaminants found on-site included heavy metals, PCBs, solvents, alkylated benzenes, phthalate esters, PAHs, and numerous other organic compounds.