LOS ANGELES (AP) — Federal regulators say six aerospace companies have agreed to pay nearly $4 million to investigate contamination and expand treatment capacity at two San Fernando Valley groundwater sites.

The North Hollywood and Glendale aquifers supply drinking water to more than 800,000 people. Chemicals used as industrial solvents were found in the water supplies in 1980.

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The U.S. Environmental Protection Agency says Honeywell International and Lockheed Martin have agreed to pay $2.2 million to help expand the capacity of equipment that is removing trichloroethylene in the 4-square-mile North Hollywood site.

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The EPA also reached a $1 million settlement with Goodrich, ITT, Lockheed Martin and PRC DeSoto that will pay for an investigation of chromium contamination in Glendale groundwater. They will also pay $750,000 for their share of EPA’s past costs.

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