The company will continue to construct, operate and purchase equipment for the facility through July 19, 2019, the Defense Department said Thursday.
Bechtel has been operating the plant that is built to store and destroy chemical agent stockpile in collaboration with URS (NYSE: URS), Battelle and Parsons under an existing contract awarded in 2002.
The team completed installation of underground utilities, electrical and control systems, titanium piping and storage systems at the site in 2013.
The contractâs ultimate goal is to close the facility after chemical weapons are destroyed.