DE SOTO, Kan. — The U.S. Environmental Protection Agency takes necessary steps to clear the way for Panasonic to build a $4 billion electric vehicle battery plant.

The EPA approved a modification to a permit issued to the U.S. Army and Sunflower Redevelopment. The permit allows for some of the property to be redeveloped.

Panasonic’s plant will be located on 300 acres of the property that is already clean.

The Sunflower Ammunition Plant closed in 1997. It was transferred to the Sunflower Redevelopment Limited Liability Company in 2005. In 2015, the Army started a 12-year process to remove what remains of the explosives and rocket propellants it created over the decades it operated.

The challenge is that hazardous materials got into many of the structures on the plant and acres of soil and ground water. Cleaning it up means exhaustive soil samples and building demolition to meet modern state and federal regulations.

Even with the permit change, the Army will be required to keep working on the remainder of the property that hasn’t been cleaned, according to the EPA’s order.

The EPA will mail notice of the permit modification to people and businesses near the site.

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