SLO landowners ordered to clean up polluted groundwater near airport

For four years, the Noll family was deemed responsible for polluting the groundwater used by them and their neighbors in rural San Luis Obispo County.

That changed on Tuesday, when the Central Coast Regional Water Quality Control Board issued a cleanup and abatement order to the current and former owners of a property found to be the source of the toxic groundwater contamination.

Those include present-day landowner John Coakley, who owns Coakley Vineyards and Apple River & Company.

The responsible parties must now take over efforts to ensure residents in the Buckley Road unincorporated neighborhood just south of San Luis Obispo County Regional Airport have healthy water to drink.

Tuesday’s cleanup and abatement order clarified that trichloroethylene, or TCE for short, was used in a laboratory at 795 Buckley Road.

The TCE was used to test asphalt from around 1978 through the mid 1980s, according to the water board’s order.

During that time, TCE likely was dumped into the sewer system or spilled on the ground, the order said.

Because TCE is heavier than water, it easily spread downward through the ground and into the groundwater of the rural unincorporated neighborhood just south of San Luis Obispo.

SLO wells contaminated with toxic chemical

In the late 1990s, San Luis Obispo County environmental health officials sampled residents’ wells and found unsafe levels of TCE in the water.

It wasn’t until after a notice sent to residents of the Buckley Road neighborhood from the San Luis Obispo County Public Health Department on Christmas Eve in 2015 that cleanup efforts began in earnest.

A total of 14 water wells had been found to be contaminated with TCE.

Thirteen of those wells fed directly into homes and businesses, with water used for drinking, showering and washing hands, whle another well was used in industrial operations.

Levels of the toxic chemical found under 795 Buckley Road were as high as 560 micrograms per liter in the soil and 2,000 micrograms per liter in the groundwater, according to water board reports.

The maximum amount of TCE allowed in drinking water in California is 5 micrograms per liter, with a goal of 1.7 micrograms per liter for tap water to avoid health impacts, according to the state’s Office of Environmental Health Hazard Assessment.

Extended exposure to high levels of TCE can possibly cause kidney cancer, Non-Hodgkin lymphoma and cardiac defects, or possibly raise someone’s risk of getting leukemia, liver cancer, Parkinson disease, multiple myeloma and scleroderma, according to the U.S. Agency for Toxic Substances and Disease Registry.

Wrong property owners first blamed for TCE pollution

After years of investigations, the water board determined in 2019 that the Noll family property at 4665 Thread Lane may have been the source of the TCE pollution because the highest levels of the pollution were found there.

Although no clear source of the TCE pollution was found at the time, the regional water board issued a cleanup and abatement order to the Nolls, who then spent years paying for groundwater monitoring and temporary water treatment systems for their neighbors.

Another investigation was then opened in late 2019 to check whether San Luis Obispo County Regional Airport could have been the actual source of the TCE pollution.

Through the 20th century, TCE was often used as a degreaser for airport equipment and other heavy machinery.

However, those investigations found the highest concentration of TCE was at the 795 Buckley Road property just south of the airport.

After looking further into the history of uses at 795 Buckley Road and retesting the soil and groundwater there, the water board was able to determine in late 2022 — more than two decades after the toxic pollution was discovered — that the 795 Buckley Road property was the source of the neighborhood’s groundwater pollution.

In July, the water board rescinded the cleanup and abatement order it had issued to the Noll family.

Cleanup order says TCE must be removed from soil, groundwater

The cleanup and abatement order issued to the current and previous owners of 795 Buckley Road went into effect Tuesday. A fitness equipment store, radio broadcaster and martial arts school rent space at that address.

The order requires the property owners to submit a water replacement plan to the water board by Oct. 9.

That plan will ensure residents in the neighborhood continue to have safe water to drink.

Also by Oct. 9, the owners must submit to the water board a work plan of how they will continuously monitor the groundwater in the neighborhood.

By Nov. 7, the owners must investigate and show the water board the full extent of the TCE pollution.

After that, by a date yet to be set by the water board, the owners must submit and implement a plan to remediate contamination from the soil and groundwater.