Research study undercuts APCD Oceano Dunes dust claims

October 4, 2020


A preliminary report from the prestigious Scripps Institution of Oceanography casts additional doubt about the need to reduce dust blowing from the Oceano Dunes onto the Nipomo Mesa. Analyses of airborne particulate samples show that blowing sand from the Oceano Dunes State Vehicular Recreation Area does not pose a health risk to people living on the Mesa, Scripps scientists said.

The state of California has spent millions of dollars to reduce dust from the Oceano Dunes following claims by the San Luis Obispo County’s Air Pollution Control District (APCD) that toxic crystalline silica posed a health risk for people living on the Mesa.

The APCD has said that 100 percent of airborne particulates blowing on the Mesa is mineral dust from the Oceano Dunes. But halfway through the Scripps Institute’s three-year study, samples from collectors on the Mesa found that only one fifth of the samples consisted of the dust.

“Twenty-six samples taken in May, the dust was less than 20 percent,” said Lynn Russell, PhD, a professor of atmospheric chemistry at the graduate department at U.C. San Diego, Scripps Institution of Oceanography. “It is exactly 20 percent on average for the higher pm 10 days. The rest was not dust and didn’t have the dunes as a source.”

San Luis Obispo County’s Air Pollution Control District (APCD) Director Gary Willey dismissed the Scripps report, and continues to blame vehicle traffic on the dunes as the primary cause of air-borne particles on the Mesa. Willey’s LinkedIn profile lists his academic credentials as a bachelor’s degree in mechanical engineering.

Aside from the 20 percent mineral dust, the airborne particles were largely comprised of water from “ambient relative humidity” and other compounds not associated with the dunes, according to the Scripps report.

The Scripps scientists focused on smaller particles of dust, 2.5 microns or less in diameter, because of health concerns. While smaller particles can enter the lungs, larger particles are generally captured in the mucus membranes of the nasal passages and are not a health risk.

In addition, the airborne sea salt and the mineral dust derived from the dunes are not toxic, according to the Scripps report.

“It is worth noting that there is no evidence that toxic compounds are associated with the two major PM2.5 sources (dune dust and sea spray) during windy conditions at Oceano Dunes, so association of PM2.5 with detrimental health effects may be without foundation,” according to the report.

In Nov. 2011, the APCD board voted to adopt “the dust rule” based on their own Phase 2 report, which blamed recreation on the Oceano Dunes for high dust levels two to four miles away on the mesa, with a claim that the dust was mainly silica.

“While not specifically measured in the study, crystalline silica can be a significant portion of wind-blown sand and soil, and is a known lung cancer hazard,” according to the APCD at a time the agency admitted that they did not know if the airborne dust actually contained the mineral silica because it was “not specifically measured in the study.”

But that did not stop then-APCD Director Larry Allen from making a dubious claim to the California Coastal Commission.

“Public exposure to unacceptably high levels of particulate matter, much of which occurs in the form of highly toxic crystalline silica, have continued to impact downwind residents,” Allen wrote in a letter to California Coastal Commission Deputy Director Dan Carl on March 27, 2017.

After 10 years of warning Nipomo residents of the dangers of silica dust, the APCD decided to run tests for silica in the air. The testing refuted the APCD’s earlier claims; concluding the dust blowing from the dunes did not contain dangerous levels of crystalline silica.

Even so, in 2018, State Parks entered into a stipulated order of abatement with the APCD. The order requires the state reduce wind-blown dust, specifically dust particles that are 10 microns or less in diameter, on the Nipomo Mesa by 50 percent. Despite agreeing to the various terms in the order, State Parks still denied that off-roading causes the dust on the mesa.

Over the past 10 years, the state has spent more than $15 million in taxpayer revenue to reduce dust concentrations on the mesa. State Parks covered approximately 200 acres of dune sand with hay, vegetation or orange plastic fencing in effort to reduce wind-blown dust.

Meanwhile, California Coastal Commission staff, which became involved because of the APCD-derived false concerns that silica from the dunes was harming the health of people living on the Mesa, is pushing to shut down the Oceano Dunes State Vehicular Recreation Area over the next five years.

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so does the APCD believe in the science of climate change but not the science of blowing dust?

Here is the problem, these agency need a cash flow to make payroll. The dunes were free fun for the public and that untapped revenue stream, in the regulatory world, needs to be monitored and metered to fund their monitoring. Free Fun are two F words in California’s governance. That simple.

Great article Karen. Lets stop the nonsense and OPEN the dunes NOW!!!!

Let me count a few of the APCD’s recent lies: 1. Saying there is silica dust when there is none; 2. Claiming OHV’s cause high dust on the mesa even though there are dust violations now on the mesa when there have been no OHV’s in the dunes for months; 3. Assuming the spring season lasts for six months; And 4. Claiming all PM measured on the mesa is dust from the dunes when in reality is but a small fraction. Why does anyone believe this county parasite of an agency is looking out for our health?

Don’t get me started about the coastal commission—they are complicit in these lies.

The coastal commission is the last defense against destruction of our coast.

I remember the days before the air pollution control district was formed. When people talked about the Nipomo/Arroyo Grande Mesa they invariably mentioned how filthy the Eucalyptus groves were. The trees were dirty, if not trimmed and cleaned up, but they provided a natural barrier from the off shore winds that blew through the area.

When developers cut down the trees to clear the land for golf courses and luxury home sites, the environmentalists did not complain because they were a non native species. The elimination of that natural filter actually increased the wind and decreased the air quality inland and led all these “newcomers” on the Mesa to look for a reason for their “lousy air”.

The APCD is only too happy to find a villain in furtherance of their own political agenda, even if science proves their theory wrong. They will ignore science, as will the coastal commission, and will eventually close the dunes to recreational vehicles.

And long after the last ATV departs the dunes the wind will still blow, the air will remain dusty and rich people will complain about it.

So the question now is….

Will the Anti-Dune Recreation Folks follow the Science?

Or will they become “Science Deniers” because the Science doesn’t fit their political agenda?

Stand-by folks….you know where this will go and it will be very illustrative.

They are always “science deniers” when it doesn’t fit the narrative or end result they want. Kind of the like the “science deniers” of a life in the womb of a women. Defund the APCD!! Like the Coastal Commission, a bunch non-elected arrogant officials pushing their environmental indoctrination filled lies and deceit to fulfill their greed for power and control. Thanks CCN for stories on this that continues to help expose them for who they really are.

In other words, the APCD has fabricated a story about a dangerous situation where one likely does not exist.

Welcome to California, where bureaucrats develop a desired conclusion, then create the data to support it.

Plenty of money wasted, especially on salaries and benefits at the APCD.