The former Operating Industries Inc. Landfill is a Superfund site located in Monterey Park, California at 900 N Potrero Grande Drive. From 1948 to 1984, the landfill accepted 30 million tons of solid municipal waste and 300 million US gallons (1,100,000 m3) of liquid chemicals. Accumulating over time, the chemical waste polluted the air, leached into groundwater, and posed a fire hazard, spurring severely critical public health complaints. Recognizing OII Landfill's heavy pollution, EPA placed the financial responsibility of the dump's clean-up on the main waste-contributing companies, winning hundreds of millions of dollars in settlements for the protection of human health and the environment.