Daily News Archive
From October 19, 2006                                                                                                        

DDT Found on School Property
(Beyond Pesticides, October 19, 2006) A recent discovery of a buried drum of DDT, a toxic pesticide that was banned in the U.S. in the early 1970s, at the Coachella Valley Unified School District maintenance yards is prompting a clean up effort. Fortunately, no children were directly exposed to the toxic chemical.

According to the story reported in the Desert Sun, the California property is owned by the Coachella Valley Mosquito and Vector Control District and is used as a storage and maintenance facility by Coachella Valley Unified School District. The cleanup effort is the second DDT-related contamination incident at the site in recent years. According to the Palm Desert-based California Regional Water Quality Control Board, clean up from the first contamination incident, which involved leaking storage drums , was completed in 2001.

Ron Falkowski, an associate engineering geologist with the board of the vector control district said that the most recent discovery occurred around 2004, when the wheel of a truck workers were driving on site crashed through the ground. Mr. Falkowski continued, "When the truck went over [the buried barrel], it collapsed. It was an old rusty barrel more than likely, it was a barrel from 30 to 40 years ago."

Assistant superintendent for business services for Coachella Valley Unified School District Carey Carlson said school officials have rented the site for several years and are aware of the contamination. Ms. Carlson said the site is useful because it allows them to consolidate maintenance equipment and workers who had been spread around the district. The area is inaccessible to students and school officials are satisfied with the cleanup efforts. Ms. Carlson continued, "Obviously, we wouldn't be leasing or having employees on a site we were concerned about."

Tests showed higher levels of DDT in the soil around the barrel. And officials feared similar findings throughout the site. However according to Mr. Falkowski, further tests didn't find any more buried barrels and the control board agreed to oversee the cleanup effort. The Riverside contractor, Engineering, Construction and Support Services, told the water control board it would come through with results of a cleanup or mitigation plan by October 1, but according to Mr. Falkowski he is still waiting to hear from the consultants.

Mr. Falkowski thinks that the plan will likely involve paving over the area where the DDT was found to prevent future exposure. Contamination at the site has already cost the vector control district $600,000 in the form of a 1998 legal settlement. Owners of a nearby date grove sued the district in 1992, claiming contamination from the site harmed their property.

DDT was once one of the most widely used pesticides to control vector borne disease and crop pests. Governmental agencies in the U.S. and internationally have classified DDT as an agent that can cause cancer and nerve damage and DDT and its metabolites have been identified as endocrine disruptors. The toxic chemical has also become increasingly associated with childhood developmental problems.

Over the last couple of decades, acceptable mosquito control practices in the U.S. have evolved from a total reliance on adulticide use for control of adult mosquitoes (a reactionary and less effective mosquito control method) to an integrated pest management approach to mosquito control.

Canceled pesticides continue to be a problem long after they have been canceled. Even when EPA determines that a pesticide use causes unreasonable adverse effects and the registration must be cancelled, it routinely allows existing stocks to continue to be sold and used for a period of months and often years. This adds to the problem of proper disposal.