The cleanup system will be developed to address groundwater contamination stemming primarily from the former Benchmark Technology facility in the City of Industry, located within the San Gabriel Valley Superfund Sites.
The company will deploy wells and a treatment plant to contain and treat groundwater contaminated by VOCs and 1,4-dioxane.
The treated water will then be discharged back to surface water or injected back into the underground aquifer, providing additional water resources to San Gabriel Valley residents.
EPA Pacific Southwest regional administrator Jared Blumenfeld said the order will protect the essential drinking water supplies in the San Gabriel Valley.
"The treatment system is designed to intercept the most highly contaminated groundwater plume and prevent it from migrating further," Blumenfeld said.
The company has already spent $10m implementing cleanup activities at the former Benchmark Technology facility through a facility-specific cleanup and abatement order issued by the Los Angeles Regional Water Quality Control Board in 1989.
Northrop is also performing the intermediate zone remedial action under a 2009 consent decree with EPA.
