For 70 years, this property served as a base for American aircraft and aerospace industries. Military-industrial use began in 1929 and personnel built bombers there during World War II. Later, North American Aviation conducted nuclear power and rocket propulsion research. NASA took over the property in 1960, using the facility to assemble rockets and missiles, and most famously, to build space shuttles for the Apollo space program. These activities contaminated the soils and groundwater on site with hundreds of different toxic chemicals including arsenic, lead, uranium, plutonium, trichloroethylene and chromium. The contamination is suspected to have caused illness in the employees who have previously worked in the new development.