Manufacturing plants, petroleum refineries and any facilities using gas-fired turbines must begin reducing emissions of five priority toxic air contaminants by 2027 under newly approved state regulations aimed at cutting the most unhealthy kinds of air pollution.
The Colorado Air Quality Control Commission on Friday completed a 15-month set of rulemakings that designated five pollutants for special regulations, boosted reporting requirements on TAC emissions, set health-based standards on the toxins and, finally, laid out ways in which companies must cut pollution. Affected firms must determine which of their facilities emit the TACs — benzene, formaldehyde, hydrogen sulfide, ethylene oxide and hexavalent chromium — at high enough rates to meet the applicability threshold and then must follow rules to reduce them.
A final two-day hearing to establish emission-control regulations brought about similar complaints as previous rulemakings, with regulated industries warning some rules are too stringent and environmental groups arguing that they don’t offer enough protection. AQCC members, however, expressed consensus on the regulations, saying they are technically feasible and use the state’s limited resources in the most efficient way possible.
“I’m very proud to be able to contribute to this,” said commissioner Gregg Thomas, the environmental quality division director in the Denver Department of Public Health and Environment who has worked on TAC controls since the late 1990s. “I feel like I could retire tomorrow and I’d be happy.”
How emissions controls on the TACs will work
The effort to limit TACs came from a 2022 law that was the state’s first effort to expand its air-pollution regulations beyond the minimization of greenhouse-gas emissions and focus them on toxins that specifically can cause cancer or respiratory illnesses. House Bill 22-1244 called for the AQCC to set up rules to measure and reduce TACs, with a special focus on disproportionately impacted communities made up residents who typically are poorer and more likely to be people of color and have been exposed to pollution.
Each of the particular TACs will have a unique set of regulations. And each generated differing levels of concern from industry and environmental groups.
Formaldehyde, which is emitted largely from spark ignition engines and gas-fired turbines, will be regulated from existing sources that exceed 4,000 pounds of emissions per year and that are located within one mile of occupied areas of DICs or within one mile of a census block with at least 20 cases of cancer per 1,000,000 residents. Any new or modified equipment that goes into service after Sept. 1, however, will only have to hit the emissions threshold in order to come under the new state regulations.
If state regulators find that a facility is exceeding the emissions threshold, they can require facility upgrades that include installation of control technologies, substitution of materials that produce fewer TAC emissions and changes in their processes. While the 2022 law also allowed legislators to include new regulations in permitting requirements, no one has brought forward a bill this session to do that.
Reliance on federal, existing regulations
Facilities that emit at least 10,000 pounds of hydrogen sulfide annually — including asphalt and roofing plants and biogas facilities — would have to install control equipment would have to install control equipment with 97% efficiency at destroying the noxious odors. Some activists had hoped to require similar controls for wastewater-treatment facilities with the same levels of emissions, but the Colorado Air Pollution Control Division determined that existing emissions reporting requirements cover that sector.
Ethylene Oxide producers, typically those factories making sterilized medical equipment, largely will have to follow newly implemented federal rules that seek the same reduction of the TACs. Control tactics for hexavalent chromium vary, from a complete ban on use of the substance by decorative chrome-plating operations beginning in June to the construction of building enclosures to limit fugitive emissions from existing facilities.
APCD staff, meanwhile, determined that most benzene emitters — upstream and midstream oil-and-gas facilities — already are covered by recently enhanced rules requiring reduction of volatile organic compounds, including benzene by the sector. The one major change in regulations coming from the hearing will affect petroleum refineries — of which the Suncor USA plant in Commerce City is the only one in the state — that will have to boost leak-detection controls in order to identify and fix leaks more quickly.
Environmentalists “disappointed and discouraged”
Environmental groups expressed particular frustration at the benzene rules, complaining that the reliance on existing regulations coupled with a small boost in leak-deduction requirements, won’t help northern Denver communities suffering from air pollution. Green House Collaboration Center Executive Director Harmony Cummings said community activists were “disappointed and discouraged,” and Denver air program specialist Nancy Fitzgerald said the thresholds for multiple TACs are “not conservative enough.”
GreenLatinos leaders asked the AQCC to boost protections by incorporating more ambient air-monitoring requirements into the regulations, reducing the hydrogen sulfide threshold to 4,000 pounds annually and expanding protections to DICs. Local-government leaders asked additionally for the AQCC to come back by 2028 with a plan on how to cut benzene emissions that goes beyond the existing VOC regulations.
However, the only change AQCC members agreed to make was to direct the APCD to provide updated data on benzene reductions by August 2028 and to report then on whether more controls on the TAC are needed. Staffers told commissioners that in a time when legislators are dealing with a $1.5 billion budget shortfall, they don’t have the resources to put up massive new regulatory programs and must take advantage of existing controls where they exist and are beginning to show progress.
Business groups worried about new emissions controls too
“Where resources demand we are taking a targeted approach, we wanted to make sure we are targeting those communities most in need,” Jessica Ferko, APCD planning and program policy manager, said.
Meanwhile, business groups such as the Colorado Oil & Gas Association, American Petroleum Institute Colorado and Colorado Chamber of Commerce — as well as regulated companies — questioned the wisdom of the one-mile compliance location requirements. The state has several references to 1,000-foot barriers for compliance in place, and the New Jersey law from which it borrowed the 4,000-pound threshold set only a 650-square-foot boundary for compliance, Colorado Chamber regulatory adviser Dave Kulmann said.
However, one mile is the standard for manufacturing-facility compliance with 2023 air-quality regulations, and it’s also part of the compliance requirements for assessing the cumulative impacts of multiple pollutants, Ferko said. And AQCC members agreed to keep that geographical requirement in place.