A possible spelling mix-up may lead investigators to a clue in whether the SLO County Regional Airport is responsible for high levels of a toxic chemical found in nearby groundwater.
The Central Coast Regional Water Quality Control Board is currently trying to find out if the airport is the source of the trichloroethene, or TCE, that somehow seeped into the private wells of the area’s residents. In addition to taking soil and groundwater samples on-site, the board also asked the county to provide historic records from the airport to determine if past practices included the use of TCE.
While the county stated in an April 15 letter to the water board that it didn’t find any records that indicate the county used, stored, or disposed TCE or other wastes on the airport property, a May 13 response from the water board to the county’s proposed work plan begs to differ.
According to that response, historic records provided by the county include hand-written documents from 1985 that listed chemicals used at the airport. Those logs list a chemical called “triethalene solvent,” a name the report says sounds similar to trichloroethylene, but is spelled like another chemical called triethylene glycol.
“Water board staff believes that it was more likely TCE that they were referring to,” the board’s response stated.
While the county has maintained that there is no evidence to-date that the airport is the source of the contamination, the board hasn’t ruled out the possibility that past use of the chemical (which was used as a solvent and degreaser) at the facility may have played a role. According to previous reporting by New Times, the airport was used by the U.S. Military between 1938 and 1946, as well as by private industries through the 1960s and 1970s, when TCE was used heavily in aircraft maintenance.
On June 1, the board announced that it had conditionally concurred with the scope of the county’s work plan, and that it expected preliminary groundwater testing results by August.