Federal environmental regulators have ordered Northrop Grumman to spend $20 million to clean up groundwater contamination in the San Gabriel Valley. The EPA says that's fourth of what will be needed to clean up the site.
The contamination is coming from the Benchmark Technology site in the City of Industry. Northrup Grumman has already spent $10 million to help clean up the former facility. The EPA says the site is the largest contributor to groundwater contamination in the area and it wants a new cleanup system built.
Northrop will install wells and a treatment plant that will send decontaminated water to the surface or back into an underground aquifer for valley residents to use.
Contamination from the facility was caused by improper disposal of chemical solvents and cancer-causing compounds.
The EPA says more than sixty companies are responsible for contaminated groundwater in the larger San Gabriel Valley region. Some are bankrupt or no longer exist. And 18 percent of the valley has been declared a Superfund site.