Colorado commission sets health-based standards for air pollutants

Despite lingering questions over just how the new benchmarks will be used, the Colorado Air Quality Control Commission adopted health-based standards for five air pollutants Friday that are poised to be lynchpins on future permitting regulations surrounding the emissions.

In doing so, the governor-appointed regulatory board took a big step in setting air-quality rules for the first time that are not aimed solely at reducing greenhouse-gas emissions — rules that reflected some concession to business requests made at the hearing. Instead, the focus on five priority air toxic contaminants, as directed by a 2022 law, seeks to identify and limit pollutants emanating from sources ranging from oil and gas wells to industrial plants to wastewater-management systems that can cause major health problems.

A wide range of pollutants

The five TACs are:

• Formaldehyde, which stems from the fuel combustion of engines and industrial boilers and can cause respiratory issues and cancer;
• Benzene, which is emitted from oil-and-gas well sites and cement-manufacturing plants and can cause cancer and create problems for reproductive systems;
• Hexavalent chromium — a product of coal-fired power plants, machine manufacturing and solvents used in glass manufacturing that can cause cancer and respiratory ailments;
• Ethylene oxide, which is emitted through commercial sterilization of medical equipment and can impact nervous and respiratory systems; and,
• Hydrogen sulfide — a product of refineries, wastewater-treatment plants and asphalt-material manufacturers that may cause headaches, nausea and psychological disorders.

The health-based standards approved unanimously by the AQCC after a two-day hearing are meant to reflect the threshold of exposure a person can have to each pollutant before there is risk of adverse impact to their health. For now, the standards are simply benchmarks noting potential levels of danger; however, state regulators already have begun discussing how they could be worked into permitting requirements — a conversation expected to pick up steam next year.

Complaints plague the process

Business leaders expressed angst that the benchmarks’ creation came before regulators identified how the standards would be used — and, thus, did not require the Air Pollution Control Division to perform an economic impact analysis on their costs and benefits. Colorado Chamber of Commerce Regulatory Affairs Advisor Dave Kulmann complained that order of process made it very hard to assess whether potential costs are realistic, and Colorado Utilities Coalition Counsel Julie Rosen called the process “especially egregious.”

As a concession to those concerns, APCD and industry leaders added a statement to the rules barring the division from using the benchmarks in a way that could trigger regulatory or economic impact without first holding another rulemaking hearing. And with that issue settled after the first day of the hearing, debate came down to the levels at which the standards should be set.

APCD created two sets of benchmarks — one citing the amount of pollutant that could be in the air before there was concern that it could cause cancer and the other citing the amount allowable before it could lead to non-cancerous health problems. AQCC members coalesced on setting the benchmark for each contaminant at a level where its cancer risk was one in one million people, despite assertions from oil-and-gas-sector associations that a 10 in 1 million risk was a more realistic and still conservative mark.

Setting benchmarks for pollutants

On non-cancer risks, most other states that regulate the TACs used a hazard quotient of 1 that is similar in nature to the cancer standard, but APCD staffers proposed a lower HQ of 0.3. That, said Colorado Department of Public Health and Environment Air Toxics Regulation Supervisor Amanda Damweber, was to account for risk of exposure to multiple contaminants as well as extrinsic risks like socioeconomic status and healthcare access.

Environmentalists backed these stringent benchmarks, and testifiers like Environmental Defense Fund toxicologist Paige Varner asked the AQCC to lower the HQ to 0.2 to protect vulnerable populations grouped into polluted neighborhoods because of systemic racism. The enacting law called upon regulators to consider the cumulative impact of multiple toxics, and the tougher standard is needed because people can be more 42 times more susceptible to health conditions under stress, Varner said.

“This should involve putting people over profits,” said Mike Foote, counsel for Communities Organized for Clean Air, a coalition that included Cultivando, the Greenhouse Connection Center and residents near the Suncor Energy USA refinery in Commerce City. “We hear companies talk all the time about why they shouldn’t have to reduce pollution … You need to flip the script.”

Ensuring benchmarks are realistic

Leaders from various sectors, however, said that making health-based standards 70% more stringent than most states not only would lead to infeasible solutions but didn’t line up with the science about what levels of concentration actually cause health problems.

Katy Goyak, a toxicologist testifying for the American Chemistry Council, said that while sensory irritation does not begin until exposure to formaldehyde at 500 to 1,000 parts per billion in the air, the state was proposing a health-based standard of .074 parts per billion. And Lucy Fraiser, a toxicologist speaking for medical-device-manufacturing association AdvaMed, said that the standards for ethylene oxide were proposed at a level far below those at which the toxic is recorded in everyday ambient air levels.

“The levels of ethylene oxide that have been monitored across the United States are not a health risk,” said Fraiser, one of a chorus of people advocating that the non-cancer health quotient for all five priority TACs should be set at the level of 1 rather than 0.3. “The standard (proposed by APCD) is unlikely to result in demonstrable health benefits.”

On the other side of that argument, Teyha Stockman, Adams County air-quality policy and program specialist, argued that the non-cancer benzene standard proposed by APCD was 23 times higher than levels recorded in some communities, making it moot.

Regulators compromise

Hearing both sets of arguments, the AQCC attempted to thread a needle.

Five of its eight members backed increasing the HQ for non-cancer risks to 1, arguing that 0.3 — and the minimal levels of the five TACs required to hit that — was too low a standard to tell residents that any exposure above that could cause health problems. Commissioner Curtis Rueter said the law intended the AQCC to consider risk of each pollutant rather than cumulative risk in standards for individual pollutants, and Commissioner Bill Gonzalez argued 0.3 was an “idealistic starting point,” while 1 was “a more realistic approach.”

But while AQCC members made that standard for four of the five toxics less strict, it ordered staff to create a separate non-cancer concentration standard for benzene, which Commissioner Gregg Thomas emphasized is a “known carcinogen.” That standard will mirror a standard set by the California Environmental Protection Agency.

Because commissioners have yet to consider how to incorporate the newly approved health-based standards into permitting, it’s unknow exactly how they could impact either public health or the operation of businesses subject to the regulations. Oil-and-gas companies, which already have been subject to new regulations in recent years limiting their nitrous oxide emissions and limiting their exploration in disproportionately impacted communities, will face one more restriction on their operations.

Potential impact on wastewater, industrial plants

But if the new standards are used to tighten permitting for medical-device facilities, that threatens to limit the operations of the Terumo BCT plant in Lakewood — and in a way that could reduce the supply of sterile intravenous catheters available to health-care facilities, AdvaMed Director of State Government and Regional Affairs Darbi Gottlieb warned. And officials from Metro Wastewater Recovery, which provides wastewater treatment for a large swath of the Front Range, said at previous hearings that costly regulations are likely to be reflected in customer bills.

AQCC members will balance that against requests from residents in areas like north Denver and Commerce City who say they’ve been exposed for too long to toxic pollutants that have led to higher rates of cancer and respiratory illnesses in their communities. With President Donald Trump rolling back environmental regulations at the federal level, the state needs to step up to protect its residents, said Rachel Jaffe, an associate attorney with the organization Earthjustice.

What comes next in regulation of pollutants

For now, though, AQCC members said they felt they have addressed the issue of what level of exposure to benzene, formaldehyde, hydrogen sulfide, ethylene oxide and hexavalent chromium is unhealthy to the population at large. And they added a statement, written by Rueter, that left no doubt that further deliberations on the subject will involve even more complex discussions.

“The risk levels selected by the commission to calculate the proposed chronic health-protective benchmarks considered that the standards must provide an ample margin of safety and consider vulnerable groups,” the statement read. “The commission recognizes that Coloradans are not exposed to a single air pollutant at a time and that the additive effect from multiple exposures may exacerbate risk.

“Because the toxicological data that are the basis of the CHPB are typically collected for only a single pollutant at a time, multi-pollutant impacts are not included in these CHPB values,” it continued. “This important consideration will be addressed in future rulemakings on the topic.”