This 429-acre aerospace test site operated from the 1950s until 2004, mostly by Wyle Labs, a private testing company based in El Segundo. The site was used primarily for propulsion system testing involving rocket motors, high pressure fluids, and cryogenics. Explosive testing occurred here as late as 2003, after which the site was closed. Most of the buildings have been reduced to foundations and concrete slabs, and the site is popular for mountain bikers, hikers, and explorers. Efforts to address the contamination of the groundwater around the site, which is located above the local high school and many homes, are ongoing. Wyle Labs still operates at other locations, and became part of the government services company KBR (Kellogg, Brown, and Root) in 2016.