San Luis Obispo County may put more pressure on state over Oceano Dunes pollution

Tribune photo by Jayson Mellom

County supervisors Tuesday will consider ratcheting up the pressure on the State Parks department to deal with a recent study linking Oceano Dunes State Vehicular Recreation Area to unhealthy levels of particulate pollution on the Nipomo Mesa.

The board will decide whether to send a letter to the State Parks Off-Highway Vehicle Recreation Division asking the agency for information about what changes it is planning to make at the park to reduce the pollution and cooperate with county health officials in evaluating potential health risks.

The letter is on the board’s consent agenda, which is reserved for noncontroversial items and acted upon in a single vote for multiple items. Supervisors will only discuss it if one of them pulls it from the consent agenda for separate consideration.

The letter comes at the same time parks officials are preparing to challenge the validity of the particulate study conducted by the county Air Pollution Control District.

The controversial study concluded that off-highway-vehicle riding at the park exacerbates dust pollution on the Mesa by destroying vegetation and breaking up a crust that naturally forms on top of the dunes, allowing small particles of sand to be blown inland.

Tuesday’s letter describes the conclusions of the study as “well-supported.” It also reasserts the county’s stake in the park as the owner of nearly 600 acres of land in the riding area, called La Grande Tract.

The letter encourages state officials to work closely with the air district “to implement a constructive and timely program of particulate mitigation.” Possible mitigations include installing wind fences and replanting the dunes to reduce wind erosion.

“We hope that the division agrees that the study’s conclusions demand serious attention from both the state and county,” the letter concludes.

The study already has the attention of state parks officials. At an April 29 meeting in Sacramento, the Off-Highway Motor Vehicle Recreation Commission heard a report on the air study.

Off-highway-vehicle division Chief Phil Jenkins said a team of outside experts in air quality and dune geology has been assigned to look at the study’s conclusions.

The division’s report states that the methodology of the study is flawed in a number of ways when it concludes that sand particles become airborne in lower wind velocities within the riding area compared to outside the riding area. Off-highway-vehicle division staffers also promise to participate in the air board’s process as it decides how to deal with the problem.

“State Parks’ objections are based on observations that the report merely documents natural occurring windblown sand and does not contain sufficient data to conclude that the (State Vehicular Recreation Area) contributes to a higher level of particulate emissions than are otherwise naturally occurring,” Jenkins stated in the report.

The county air board will meet next on May 19. Air district staff has promised to update the board on the particulate study at future meetings.