20th century growth thumb|right|Interstate 10 in Beaumont, 1963 During the Cold War, a Lockheed rocket test site operated by Simi Valley–based Rocketdyne was established south of the town in Potrero Canyon. In late 2003, the majority of the Potrero Canyon site was sold to the state of California. Toxic chemicals used in rocket fuel and site test activities have been found in the soil and groundwater at the site, and planning is underway to begin cleanup sometime in the next few years. Plans are being developed by the California Department of Fish and Game to allow public access.
20th century growth thumb|right|interstate 10 in beaumont 1963 during the cold war a lockheed rocket test site operated by simi valley–based rocketdyne was established south of the town in potrero canyon in late 2003 the majority of the potrero canyon site was sold to the state of california toxic chemicals used in rocket fuel and site test activities have been found in the soil and groundwater at the site and planning is underway to begin cleanup sometime in the next few years plans are being developed by the california department of fish and game to allow public access