Lake Sandy Jo (M&M Landfill)

Overview

Lake Sandy Jo, also called the M&M Landfill, is a 50-acre former landfill in Gary, Indiana. It was excavated in the 1960s during construction of Interstate 80, then filled between 1971 and 1980 with heavy metals, construction debris, garbage, and industrial waste, all deposited without a permit. The EPA placed it on the National Priorities List (NPL) in 1983, which flags sites needing formal investigation and cleanup.

More than 150 chemical substances have been found in soil, sediment, groundwater, and surface water at the site. Metals include arsenic, cadmium, chromium, lead, mercury, and nickel. Volatile organic compounds (VOCs) such as chloroform, toluene, and xylene are present, along with polycyclic aromatic hydrocarbons (PAHs) like benzo[a]pyrene, pesticides including DDT, polychlorinated biphenyls (PCBs), and phthalates.

The cleanup is organized into three operable units covering a soil cover project, a waterline remediation, and a sitewide program. The selected remedy for the soil cover unit includes a landfill cap, excavation of contaminated soil, groundwater monitoring, and deed restrictions limiting future land use. Construction ran from 1988 through September 1994. A 2008 modification shifted the focus toward institutional controls and opened the door to limited recreational and commercial reuse. Groundwater contamination levels have steadily declined, and EPA determined that contaminated groundwater is stabilized in its original area. The site is fenced, deed-restricted, and a City of Gary ordinance bans new groundwater wells within city limits, keeping drinking water risks in check. All cleanup goals have been met, and no unacceptable risks are associated with current or anticipated future land uses. In 2021, EPA pursued a partial deletion of the landfill and soil portions from the NPL, signaling the remedy was successfully implemented.

EPA conducts Five-Year Reviews to confirm the cleanup continues to protect public health and the environment. The most recent review, completed in July 2021, confirmed response actions match the selected remedy. A seventh Five-Year Review is estimated between July and September 2026. Between 2021 and 2022, EPA and the Indiana Department of Environmental Management (IDEM) hosted workshops with the City of Gary and community members to explore reuse options for the site.

Community members can share information about site conditions or concerns during the upcoming Five-Year Review period. Site documents, including the 2021 Six-Year Review and the 2020 partial deletion justification, are available at the Gary Public Library and Cultural Center at 220 W. 5th Avenue in Gary.