Will data spur change in dust mitigation on the Oceano Dunes?

June 4, 2022

Oceano Dunes dust mitigation fencing


After installing more than 230 acres of dust mitigation measures within the 1,000-acre off-highway vehicle riding area at the Oceano Dunes, the number of violations for exceeding the state’s pollution standard on the Nipomo Mesa in May 2022 was the highest in eight years, which further refutes the argument that vehicles on the dunes are the cause of pollution on the mesa.

For more than a decade, the San Luis Obispo County Air Pollution Control District (APCD) and Nipomo Mesa residents have clashed with State Parks and off-road vehicle enthusiasts over the cause of particulate pollution in the air at the Nipomo Mesa. The APCD has claimed that on windy days, the pollution is almost entirely due to mineral dust particles blowing from the Oceano Dunes State Vehicular Recreation Area, which is located more than two miles from the mesa.

State Parks entered into a stipulated order of abatement with the APCD in 2018. Among other things, the order requires State Parks to reduce the number of violations of the state’s particulate pollution standard on the Nipomo Mesa by 50%. These violations typically occur in the spring months, particularly in May, when strong on-shore prevailing winds blow in south San Luis Obispo County.

Under the APCD’s order, State Parks began closing large portions of the vehicle riding area and installing fencing and vegetation in an effort to reduce the amount of mineral dust blowing from the park’s dunes. More than 230 acres have been covered thus far.

The APCD has claimed these measures have been successful at meeting the violation-reduction metric of their order. However, this past May the number of violation days has increased to its highest level in eight years despite the mitigation efforts.

Violations of the state’s particulate pollution standard during the month of May, from 2015 through 2022:

  • 2015 –  5 violations
  • 2016 –  4 violations
  • 2017 – 10 violations
  • 2018 –  9 violations
  • 2019 –  6 violations
  • 2020 – 12 violations
  • 2021 –  7 violations
  • 2022 – 16 violations

While the APCD claims that the particulate pollution on the Nipomo Mesa is almost entirely mineral dust, the Scripps Institution of Oceanography analyzed the particulate and determined that at most only 14% of what the APCD measures on the mesa consists of mineral dust.

Scientists refer to the process of dust emissions from the dunes as saltation, which is a “natural dune building process that causes sand and finer material to be pushed and bounced downwind.” The saltation process generates mineral dust.

In its attempt to appease the APCD, State Parks has spent more than $22 million (page 5 of report) to stop saltation in the dunes by planting vegetation and installing fencing.

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And this folks, is ‘Politics’.

Hey Jimmy Paulding, I hope you put all that in your Bruce Gibson/Adam Hill bong and smoke up the lies. Good Christ!—the dems in this county…”Hypocrite” doesn’t even begin to explain their standing.

And State Parks? Thanks for nothing. I hope someone sues you to get back the money you continue to waste on a problem that does not exist.

What an incredible waste of money. The roads are garbage, homelessness is rampant, and water is in short supply…. but they’re going to spend that much money trying to stop the wind from blowing sand, at the sand dunes. Hard to even believe :/

It is funny how both sides only see the “data” that supports their viewpoint. This article completely ignores the fact that May 2022 was perhaps the windiest May in recent history. Dust mitigation wasn’t going to do much when the afternoon winds were howling day after day. John Lindsey even wrote an article about the historic winds of May. But I’ll be honest about my views. I would like to see all vehicles off the dunes and beach. I don’t care about sand blowing or not.

Do you realize how absurd you sound? Yes the wind blows and maybe it’s increasing even more. But what the hell does that have to do with the OHV recreation on the dunes?! Nothing! The APCD has convinced Parks to chase its tail, spending public money for nothing. And you mention data. What data does the APCD have other than making sh*t up, such as their silica lie?