The SLO County Air Pollution Control Board on March 24 voted to receive and file a controversial study which blames off-road vehicles for poor air quality in the Nipomo Mesa. Mesa residents concerned about the air pollution filled the room, leaving their signs reading ‘No OHVs’ and ‘Health Over Recreation!’ abandoned outside the San Luis Obispo County building.

The 9-1 vote ultimately directs staff to investigate steps the county can take to improve the air quality and encourage cooperation with the California State Parks Department. Two board members, Jan Marx and Joe Costello, were absent.

Though questions were raised about components of the study from members of the Board and audience, lead APCD administrator Larry Allen said no scientific study can prove something with 100-percent certainty, but the overwhelming weight of evidence points to off-road vehicles as the cause of high concentrations of particulate matter in the Nipomo Mesa atmosphere.

“I have heard challenges to the process [of how the study was done], but not any contradictory evidence,” said Board member and District Three supervisor Adam Hill. “I can’t in good conscience tell Nipomo residents to wait on this. Public health is our most essential duty—it takes precedence over everything.”

The only member to vote against the motion was Pismo Beach Councilman Kris Vardas, who said he’s “not quite sure we’ve reached the perfection we can achieve” in the study. Vardas said he would like to see the Board further review public comments in moving forward.

Pismo Beach City Councilman Ed Waage presented questions about the study to Allen and head APCD researcher Joel Craig, including queries about seasonal variation in particulates.

Researchers will return to the next Board meeting May 19 to further address public comments.