The contamination was discovered in 1980 and resulted in the closing of 20 water supply wells and intensive cleanup efforts in the following years.
Many of the wells responsible for supplying water to these areas lay down gradient from the two contamination plumes that resulted from the pollution.
[1] In 1980, two volatile organic compounds (VOCs), trichloroethylene (TCE) and tetrachloroethylene (PCE) were discovered at the Newmark well fields.
[3] In 1993, the EPA took actions to pump and treat millions of gallons of contaminated water to control the spread of pollution plumes into other parts of the aquifer.
[1] In 1996, the city of San Bernardino sued the federal government for the Army's involvement in the contamination of the groundwater.