BY KAREN VELIE
For more than a decade, San Luis Obispo County’s Air Pollution Control District (APCD) warned about silica dust blowing inland from the Oceano Dunes.
It causes cancers, and lung and kidney disease.
It was the result of off-roading at the Dunes.
It was made up.
Studies of air quality samples taken by both the APCD and State Parks consistently failed to find detectable levels of the dust. There was, in the words of an expert on the risks of silica dust, “no evidence of a realistic pulmonary (inhalation) risk with respect to respirable crystalline silica.”
Even so, silica dust was an effective way to justify APCD regulation of the dunes. The APCD continued to warn mesa residents that off-highway vehicle recreation at the Oceano Dunes State Vehicular Recreation Area was causing silica dust to blow on their properties. That, the APCD said, meant people were at risk of cancer and other diseases.
The reports alarmed state and local agencies. They repeated the APCD’s warnings. Local media and the public bought into the claim. The silica dust scare affected Nipomo Mesa real estate transactions and property values. Some real estate disclosure forms, required to warn buyers of risks associated with properties, were modified to note health hazards of crystalline silica in the air at the mesa.
The form quotes from both the APCD’s Phase 2 report the Phase 1 report’s silica statements. The forms also note that the World Health Organization’s classification of “inhaled crystalline silica from occupational sources as carcinogenic to humans.”
It was ultimately California State Parks, the managers of the Oceano Dunes, that refuted the silica fabrication. But that was more than 10 years after the APCD started pushing its silica dust argument.
In 2007, the APCD first initiated the belief that the mesa air was filled with silica dust in a Phase 1 report, which documented airborne dust levels on the Nipomo Mesa that exceeded air quality standards. Silica is mentioned only once in the lengthy report, and that is on the last page, in a vague reference to the upwind coastal dunes.
“Sand particles are high in crystalline silica, a known carcinogen with a high risk factor,” according to the report.
Relative to other minerals, silica — also known as crystalline silica and quartz — is quite hard. The energy necessary to break it into fine dust particles is typically found in industrial and mining settings. The particles are 100 times smaller than what is found on beaches and sand dunes. Because of the acute health risks, exposure to silica dust is specifically regulated by state and federal health and safety agencies. OSHA says silica exposure remains a serious threat to nearly 2 million U.S. workers, including more than 100,000 in high risk jobs, such as abrasive blasting, foundry work, stonecutting, rock drilling, quarry work and tunneling.
In March 2010, the APCD held a public workshop to announce the results of its Phase 2 report, and to receive written questions about their findings. The APCD subsequently prepared a document of responses to submitted questions,
“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’s written response.
In Nov. 2011, the APCD board voted to adopt “the dust rule” based on the Phase 2 report, which blamed recreation on the Oceano Dunes for high dust levels two to four miles away on the mesa, and a claim that the dust was mainly silica. The APCD proposed a $1,000 fine to State Parks for each day dust concentrations on the mesa reached a certain level.
During the 2011 meeting, APCD board members and the public voiced their concerns over silica dust.
Despite having previously admitted silica was “not specifically measured” in their Phase 1 and Phase 2 studies, then-APCD director Larry Allen invoked silica as he argued for the dust rule, and the ability for his agency to fine the state.
“We found that on days when we were exceeding the standards, it was predominately silica, which is sand essentially,” Allen said during the 2011 board meeting.
At that time, the APCD had not yet tested the dust blowing on the mesa for silica.
In 2011, unaware that silica had not been found in the two studies, the APCD Board voted to adopt the dust rule.
With the passage of the dust rule, Allen’s claim that silica dust was blowing from the Oceano Dunes to the mesa was repeated many times by many people.
Arlene Versaw, an organizer for the Mesa Community Alliance, is arguably the most vocal advocate of the APCD’s silica dust claims.
In Feb. 2016, Versaw created a GoFundMe page to raise money for the group’s primary cause of holding State Parks accountable for silica dust blowing on the mesa through a nuisance lawsuit.
“Why is your donation so critically necessary?” Versaw wrote on GoFundMe. “These ‘particulates’—fine silica particles—are dozens of times smaller than a human hair. They can cause respiratory problems, heart and lung problems, even premature death … with children and seniors most at risk.”
For years, Versaw repeated the APCD’s claim that the dust blowing on the mesa was primarily composed of silica in newspapers and in letters to the editor.
A few examples of Versaw’s assertions:
● “Mesa residents are subjected to hazardous silica dust that truly threatens human health,” San Luis Obispo Tribune, March 22, 2016.
● “The specific pollutant we face – silica dust – is cumulative and does not leave the body,” The Pulse, Nov./Dec. 2016.
● “For years, it has been known, well documented and reported that the Ocean Dunes Off-Highway Vehicle Park is the source of particulate matter silica dust, which is a very serious health hazard.” San Luis Obispo Tribune, June 30, 2017.
● “Second, the problem is not SAND. It is silica dust,” San Luis Obispo Tribune, Jan. 15, 2018.
● “The funds are being spent unnecessarily all right—but the APCD is merely defending itself and defending its duty to do its job of protecting Nipomo Mesa residents from hazardous air pollution,” SLO New Times, July 20, 2016.
In her New Time’s commentary, Versaw chastised former APCD Board member Debbie Peterson, who was consistently critical of the dust rule and the nearly $400,000 cost to taxpayers for the legal challenge that invalidated the dust rule. In the same article, Versaw praised Supervisor Adam Hill, a public official known to loudly challenge those who questioned the validity of Allen’s silica dust assertions.
Versaw also claimed to know of information that “undermines any claim that the Oceano Dunes OHV is not the source of the hazardous silica dust.”
In reality, there was no information. The APCD had not yet conducted any testing for silica dust in the mesa air. Apparently, unbeknownst to Versaw, it would not be until April 2017 that the APCD finally began sampling and testing mesa air specifically for silica dust.
Versaw and other members of the mesa community would remain unaware of the testing for nearly another year because the APCD remained silent about the testing and the results.
California Coastal Commission puts weight behind APCD’s silica argument
Unaware that testing of silica in the air on the Nipomo Mesa had not yet occurred, in 2017, the deputy director of the California Coastal Commission’s north central coast district also began promoting the APCD’s silica claims.
The commission is tasked with protecting California’s coast and ocean for present and future generations. It does so through planning, regulating development, and utilizing the “rigorous use of science,” according to the commission.
In 2017, then-APCD Director Larry Allen spurred California Coastal Commission Deputy Director Dan Carl’s interest in the mesa in a letter in which Allen repeated his unsubstantiated claim that the dust in the mesa air is mostly silica.
“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 Carl on March 27, 2017.
Two days later, in a letter to State Parks, Carl repeated the APCD’s false assertion that dust on the mesa was primarily comprised of silica, and as such, was a public nuisance.
“The dust emissions are largely comprised of crystalline silica, which is known to be highly toxic,” Carl wrote in the March 29, 2017 letter. “Furthermore, the dust emissions constitute a ‘public nuisance’ as that term is defined in Civil Code Section 3480 because the dust emissions affect County residents in residential areas downwind of the Oceano Dunes State Vehicle Recreation Area riding areas. The dust emissions are significant, considering that the Superior Court and the APCD have characterized them as ‘unacceptably high,’ ‘highly toxic,’ and ‘a significant public health threat.’”
After 10 years of warning Nipomo residents of the dangers of silica dust, the APCD decided to run tests for silica in the air.
From April through June 2017, the APCD collected and tested dust samples from the Nipomo Mesa “CDF” air monitoring station. However, the results of the testing, or even the fact that testing had been conducted, were not made public.
Months later, an APCD staffer admitted to State Parks that they had tested for silica, but gave no indication of the results. Eventually, the APCD provided State Parks the lab reports.
State Parks tasked John Kelse, an industrial hygienist with experience in assessing risks posed by silica dust, to analyze the APCD laboratory reports. Kelse found no risk to the residents on the mesa from silica.
“The analytical reports of the air filter samples collected at the CDF air monitoring station in April, May, and June 2017 offer no evidence of a realistic pulmonary inhalation risk with respect to crystalline silica,” according to Kelse.
State Parks then asked Kelse to oversee its own collecting of air filter samples and have the samples submitted to an accredited laboratory for silica analysis. Air filter samples were collected in March 2018 within the Oceano Dunes and at the CDF air monitoring station on the mesa.
“Results for all air filter samples collected on March 8, 2018 and analyzed for respirable crystalline silica (quartz) are below the detection limit of the analysis applied,” according to Kelse. “These results are consistent with those presented in my prior report dated Dec. 14, 2017. As such, the presented and reviewed data provide no evidence of a realistic pulmonary (inhalation) risk with respect to respirable crystalline silica.”
Kelse noted that silica that creates health risks in industrial settings is not typically found in beach and dune environments.
“As stated in my prior report, the respirable-size fraction of crystalline silica found in industrial environments is typically 100 times or more smaller (due to employed physical forces associated with processing) than that typically encountered in sand in beach and dune environments,” according to Kelse. “For this reason, it is unsurprising that crystalline silica was not detected in the air filter samples collected.”
For years, disagreements over the validity of the dust rule spurred discord between State Parks and the APCD. The dust rule contained a provision for imposing $1,000 a day fines against State Parks whenever dust concentrations on the Nipomo Mesa reached a certain level.
In July 2017, the APCD issued State Parks a notice of violation for failure to comply with the dust rule. Technical arbiter Dr. W. G. Nickling was enlisted as a special master in an attempt to resolve the ongoing discord that led to the notice of violation. Both State Parks and the APCD then provided Nickling documents in support of their respective positions.
“The submission report provided by Parks is highly focused, well documented, and attempts to address the issues related to the NOV straight on and without embellishment,” according to Nickling’s Oct. 11, 2017 mediation report. “It stands in strong contrast to the submission provided by APCD, which contains inflammatory language, demonstrates a notable lack of objectivity, and fails to provide direct reference to supporting documentation and data.”
Ultimately, Nickling recommended the withdrawal of the notice of violation because it was “unnecessarily punitive and unproductive.” Additionally, he encouraged cooperation between the parties to resolve concerns related to dust on the mesa.
Appearing to ignore Nickling’s advice, Allen asked the APCD Board to vote to convene the APCD’s Hearing Board in an attempt to assert more authority over State Parks. However, the APCD Board denied Allen’s request based on the mediation report. The five-member Hearing Board is a quasi-judicial body whose purpose is to decide on matters of conflict between the air district and industry, according to the APCD.
Undeterred, Allen filed a petition with the Hearing Board for an order of abatement against State Parks. The Hearing Board granted Allen’s request, which led to a series of public meetings that extended from Nov. 2017 through April 2018.
At a March 21, 2018 meeting, Hearing Board Member Robert Carr questioned Allen over the lack of transparency regarding the 2017 silica dust testing. In the exchange, both Allen and Carr initially conflated the mineral silica with the synthetic compound silicone. Eventually, Carr landed on the proper term, followed by Allen.
The exchange highlighted notable departures from previous declarations the APCD made, including that the dust in the mesa air was predominately composed of silica.
Carr: “I’d like to know Mr. Allen, why you didn’t release the silicone data when you first got it? And I wonder if you have a chance to complete your comments?
Allen: “Well, so, the silicone data that was originally, you know the rule is not based on silicone at all, we do understand that it’s a natural component of all beach sand…”
Carr, interrupting: “Why didn’t you release the data when you first got it?”
Allen: “Well, so, when we look at it there was a new OSHA standard that came up and the public was saying we think we’re seeing levels that might be exceeding that standard. We only took four samples, and we weren’t doing a study. We just wanted to get an idea to see if this was worth exploring. If we were going to release the data, we would have wanted to have done a much broader study that would give us a much better understanding of what those concentrations…”
Carr, interrupting again: “Where’d the idea come from in the first place to test for silica?”
Allen: “Because the public brought it up, ah, OSHA came up with a brand new standard of that 50 micrograms and members of the public were coming to our board saying, well, you know — the concentrations that we’re breathing down there, if there’s a majority of it is crystalline silica we’re probably exceeding even the OSHA standard. And so we agreed to take a few samples out there. We weren’t hiding any data.”
Carr: “So I hope this is the last we hear about silica.”
Allen: “Well, you know it’s a red herring and I’m kind of disappointed it’s even mentioned in the, ah, abatement order, in the proposed abatement order because it’s really, it has no bearing whatsoever.”
Allen’s red herring comment contrasts starkly with the many previous warnings given by the APCD regarding silica dust.
In 2018, State Parks entered into a stipulated order of abatement with the APCD. The order mandates that 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.
Meanwhile, the APCD quietly continued its quest to find silica dust in the air on the mesa that could be tied to Oceano Dunes. In 2018 and 2019, APCD staffers collected multiple air filter samples at their CDF air monitoring station for silica analysis. However, they again came up empty-handed.
“None of the 26 samples exceeded the Occupational Safety and Health Administration (OSHA) 8-hour workplace health-based standard for respirable crystalline silica. An estimate of the 2018 annual average silica concentration does not exceed the California chronic Reference Exposure Level,” according to APCD’s 2019 report on the testing.
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.
Additional dune-covering projects are anticipated in the coming months and years, under the disputed theory that the obstructions will help reduce dust produced by the blowing sand.
State Parks has little to show for the money spent. In March, the state temporarily closed the Oceano Dunes to vehicle recreation because of the coronavirus.
During May, the windiest month of the year, excessive dust days more than doubled with no off-road vehicles on the Oceano Dunes, data from two Nipomo Mesa air quality monitoring sites show.
In January, State Parks Director Lisa Mangat shut down approximately half of the camping area, and about 5 percent of the riding area at the Oceano Dunes, or approximately 50 acres near the shoreline to reduce sand blowing on the mesa. The area was popular with campers, and provided 50 percent of the park’s camping availability.
A 2017 study showed visitors to Oceano Dunes Recreational Area spent more than $200 million a year in the county. It has not yet been determined what economic losses the county will incur because of the closures.
Even though the APCD’s silica fallacy has been refuted, the California Coastal Commission continues to find that off-road vehicle recreation is responsible for sand blowing two to four miles away on the Nipomo Mesa, based on APCD reports.
On July 9, the California Coastal Commission deputy director will report on restrictions to off-road vehicle use on the Oceano Dunes, which were allegedly implemented to protect the health of Nipomo Mesa residents.