Oceano Dunes dust control measures are lawful, SLO judge rules

Mackenzie Shuman
·3 min read

After a yearlong court battle, a San Luis Obispo Superior Court judge ruled that dust control measures at Oceano Dunes State Vehicular Recreation Area are lawful.

Superior Court Judge Tana Coates made her ruling on March 21, deciding against Friends of Oceano Dunes. The off-road riding advocacy group filed the lawsuit in late January 2022 against the California Coastal Commission.

Friends of Oceano Dunes had accused the Coastal Commission of abusing its discretion and illegally permitting 130 acres of dust pollution control measures to be installed at the popular park in southern coastal San Luis Obispo County.

The off-highway vehicle advocacy group said in its January lawsuit that the Coastal Commission permitted the additional dust control measures at the Oceano Dunes without proper approval from SLO County.

The Coastal Commission also approved the dust control measures under an invalid rule, the lawsuit alleged.

Cars on the Oceano Dunes south of Arroyo Grande Creek on March 22, 2021. A new agreement in December 2021 temporarily lifts a restriction preventing vehicles from crossing the creek any time it’s flowing to the ocean. Now, cars will be allows cars to cross as long as the water is no more than 12 inches deep. The Coastal Commission had voted to ban vehicle crossings of the creek if any amount of water flowed into the ocean.

Coates disagreed, noting that the county and Coastal Commission had properly agreed on a so-called “consolidated permit” in 2012, therefore allowing the state agency to approve new dust control measures to follow the San Luis Obispo County Air Pollution Control District’s Rule 1001.

Rule 1001 requires California State Parks to find a way to reduce dust emissions from the Oceano Dunes when an air quality monitor on the Nipomo Mesa downwind of the riding area of the dunes measures particulate matter levels that are 20% higher than an air quality monitor that is not downwind from the riding area.

Friends of Oceano Dunes had argued the Coastal Commission did not have the authority to approve any more dust control measures at the dunes because Rule 1001 essentially been replaced by the stipulated order of abatement agreed upon in court by the air district and California State Parks in 2019.

The stipulated order of abatement originally required State Parks to reduce dust emissions from the Oceano Dunes by 50% by 2023 according to 2013 baseline levels.

Revegetation of targeted portions of the Oceano Dunes SVRA with native plants like this lupine slow winds and allow larger sand grains to settle and cover finer particulate. By “tripping” the wind from accelerating across the dune surface, particulate emissions are reduced.
Revegetation of targeted portions of the Oceano Dunes SVRA with native plants like this lupine slow winds and allow larger sand grains to settle and cover finer particulate. By “tripping” the wind from accelerating across the dune surface, particulate emissions are reduced.

In October, that target changed to require State Parks to “eliminate emissions in excess of naturally occurring emissions” from the Oceano Dunes — reducing dust by about 40.7% by October 2024, according to 2013 baseline levels.

Coates noted in her ruling that “even in the air district is currently only actively enforcing the (stipulated order of abatement), that does not invalidate Rule 1001. Rule 1001 remains valid and binding on State Parks.”

“The dust control measures approved in the 2021 amendment are aimed at particulate matter reduction and will aid State Parks in coming into compliance with Rule 1001,” Coates continued in her ruling.

The 130 acres of dust control measures approved by the Coastal Commission in December 2021 were installed by the spring of 2022.

Every year since 2011, State Parks has implemented dust control measures in an effort to curb the emissions from the dunes. Although they are naturally dusty, studies show that areas with more vehicle activity emit more dust than other areas at the Oceano Dunes.

In total, 700 acres of the 1,500-acre off-roading park in southern San Luis Obispo County are set aside for dust mitigation, including for temporary sand fencing, permanent re-vegetation or foredune restoration.

As of midday Monday, Friends of Oceano Dunes President Jim Suty had not replied to requests for comment about the lawsuit.