SLO County Airport submits TCE testing plan 

The investigation into how high levels of a toxic chemical solvent showed up in local wells continues, with state investigators looking at the SLO County Regional Airport as a possible source.

On April 15, SLO County submitted a detailed plan to the Central Coast Regional Water Quality Control Board to test whether the airport was the source of high levels of trichloroethene, or TCE, recently found in private wells in the Buckley Road area of SLO. Since October 2015, a total of 64 wells have been tested for the chemical, with 12 of them testing positive for TCE in amounts above federal drinking water standards.

According to emails obtained by New Times, the airport was mentioned as a possible source of the TCE contamination as early as November of last year.

“There’s been TCE in this neighborhood for some time, but not at this level,” Leslie Terry, an environmental health specialist for SLO County, wrote in a Nov. 3 email to a water board official. “There are rumors of a potential plume moving over from the airport … but nothing is confirmed.”

Those rumors only seemed to grow as the investigation continued. On Feb. 1, County Director of Airports Kevin Bumen issued a press release claiming that the airport was “not likely” the source of the contamination. But the Regional Water Quality Control Board never ruled out the airport as a possible source. The board responded in a Feb. 23 letter, giving the airport until April 15 to submit a work plan for further testing and investigation at the airport. 

The work plan was submitted by the deadline, and calls for soil, soil gas, and groundwater tests in multiple areas, including locations northeast of the airport’s runways, according to Thea Tryon, a senior engineering geologist for the regional water board. Tryon said the county will also submit historical aerial photos, information on supply wells, and hazardous waste manifest plans. The board hopes to begin testing in July and have the results by mid-August.

“We are of course interested in getting this work done as quickly as possible as I’m sure the impacted well owners in the Buckley area are as well,” Tryon wrote in an email response to New Times.

While the testing has yet to begin, an estimated 48 residents in the impacted area have already filed claims against the county, according to John Fiske, the attorney representing the residents. Those claims point the finger directly at the airport, stating that the county was negligent when it allowed the dumping of TCE and other toxic chemicals on airport property in the 1960s and 1970s. 

As of April 20, the water board had not officially identified the source or cause of the contamination.