Trichlorethylene (TCE) Pollution in Tucson Water

From the Librarian Files

Trichlorethylene (TCE), an industrial solvent, was routinely dumped in areas of South Tucson during the 1950s. The Tucsonans who lived in these areas have had various cancers as a result of this pollution.

The boundary of the area contaminated by TCE is roughly south of 22nd street, north of Los Reales Road, east of Interstate 19 and west of Del Moral Boulevard.

Hughes Aircraft and the city of Tucson were accused of dumping TCE in the water table for 29 years, beginning in 1952. A lawsuit against the city was settled in 1981 for $31 million, and in 1991 a suit against Hughes Aircraft was settled for $84.5 million. In 1981 the Environmental Protection Agency (EPA) tested water wells on the south side of Tucson and found TCE levels were beyond the EPA limits.

In 1983, the EPA set a large southside area of Tucson on its Superfund cleanup list.  In March 2000, a $35 million plan was secured for cleanup of the contaminated areas.  Other government supervised cleanups started about 20 years ago. The last settlements involving TCE lawsuits occurred in June 2006.

Timeline for TCE law suit

  • 1952: Hughes Aircraft starts using trichloroethylene to clean dirty or greasy metal parts at Air Force Plant 44, a government-owned missile factory south of the airport. Until the early 1980s, Hughes disposes of the TCE primarily by pouring it into open pits and occasionally by pouring it directly on the ground and down drains.
  • 1981: The Pima County Health Department finds serious soil and water pollution on the South Side resulting from industrial waste disposal practices. It closes all polluted water wells.
  • 1982: The U.S. Environmental Protection Agency adds the Tucson Airport Authority to its Superfund national priority list. The contamination covers an area approximately one-half mile wide and five miles long.
  • 1987: Soil and water cleanup begins.
  • 1989: The City of Tucson settles a lawsuit with 1,600 South Side residents for $35 million. Some of the insurers challenge their liability in the case.
  • 1991: Hughes Aircraft and other companies settle a lawsuit with 1,600 South Side residents for $84.5 million.
  • 1994: The Tucson Area Remediation Project, a treatment plant for contaminated water, begins full operation.
  • 1998: Hughes, now Raytheon Missile Systems Co., and other firms settle a suit in December with 247 residents. Two cases are still pending in federal court.
  • 2006: The last of three insurers agrees to terms with plaintiffs' attorneys, pushing the total settlement beyond $130 million.

Information Resources about this Site


"Fears on TCE linger after years." Arizona Daily Star. April 19, 2003 Page B3.

"Last TCE settlement going to plaintiffs." Tucson Citizen.  June 9, 2006 Page A16.

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