Issue Date: July 27, 2009
Power Plant Pollution
Coal-fired utilities and state regulators have been groping around in a haze of uncertainty ever since a federal court threw out two major air pollution regulations last year. As a result of the voided rules, electricity generators hesitate to invest in pollution-control equipment because they don’t know how much they’ll have to cut their emissions. And 28 eastern states are struggling to reconfigure their plans to meet federal air quality standards. Meanwhile, pollution from utilities, linked to a variety of health ailments, continues unabated.
This situation may soon come to a resolution. The question at this point is whether it will be Congress or the Environmental Protection Agency that replaces the two rules.
The Bush Administration issued the two air pollution regulations in 2005. One of the regulations targeted utilities’ emissions of sulfur dioxide, a contributor to particulate pollution, and nitrogen oxides (NOx), which are precursors to ground-level ozone. Called the Clean Air Interstate Rule (CAIR), it applied to 28 eastern states that have trouble meeting air quality standards for particulates and ozone. The rule capped utilities’ releases of SO2 and NOx and then let facilities that cleaned up their emissions sell pollution allowances to dirtier units (C&EN, July 21, 2008, page 13). Critics, including state regulators, complained that the rule did not cut emissions fast enough or deeply enough.
The second rule was the first attempt anywhere to curb mercury emissions from coal-fired power plants. Like CAIR, this regulation relied on a cap-and-trade system. But critics feared it would create hot spots of the neurotoxic metal downwind of units that bought pollution allowances instead of cleaning up their emissions. (C&EN, Feb. 18, 2008, page 6).
In separate cases in 2008, a federal court determined that each of the rules violated the Clean Air Act.
Now, both Congress and EPA are interested in replacing the two rules as quickly as possible. Although EPA has more technical expertise in air pollution abatement, lawmakers could act faster. This is because EPA, like all regulatory agencies, must strictly follow federal procedures before it can issue a rule. This process generally takes a minimum of 18 months. It involves gathering scientific and technical data; analyzing legal issues; proposing the rule; soliciting and responding to public comments; and issuing a final rule.
In contrast, Congress could implement a fix quickly by passing a law. Legislation would have greater benefits than a rule made by an agency, especially for CAIR. First, Congress could extend the SO2 and NOx control program to all of the U.S. Because of limitations in the Clean Air Act, EPA must confine CAIR’s reach to cover only utilities in heavily polluted states. Second, a new law would virtually eliminate the chance that the new standards will get embroiled in a lengthy court battle. A legal challenge is practically a given if EPA issues a rule because most of the agency’s major air pollution regulations end up in court.
Nonetheless, the question remains whether lawmakers, bogged down with other pressing issues such as health care reform, will take on a task that a federal agency is equipped and willing to handle.
Spearheading congressional interest in replacing the regulations is Sen. Thomas Carper, a moderate Democrat from Delaware who chairs the Senate Environment & Public Works Subcommittee on Clean Air & Nuclear Safety. For years, Carper has pushed for legislation to control utilities’ emissions of SO2, NOx, and mercury.
Earlier this month, Carper held an oversight hearing on the prospects for replacing CAIR and the mercury rule. There, it became clear that EPA is set on tackling the job itself, rather than asking Congress for a quick fix.
Regina A. McCarthy, EPA assistant administrator for the Office of Air & Radiation, told Carper’s subcommittee that EPA is working on new versions of both rules. They are expected to be finalized in 2011.
Revamping the mercury rule appears to be a more straightforward task for the agency than redoing CAIR. Unlike its predecessor, the upcoming rule will not involve a cap-and-trade system for mercury, McCarthy said. Instead, it will specify that each coal-fired power plant must install pollution-control technology to reduce emissions of the metal.
If EPA issues a technology-based standard, the rule likely would quickly cut the 48 tons of mercury spewed out by U.S. power plants each year by at least 90%, according to the Government Accountability Office (C&EN, July 20, page 32). A study by GAO, the investigative arm of Congress, has found that relatively inexpensive control technology—sorbent injection—has proven highly effective for removing mercury from power plant emissions. This technology was not widely demonstrated in 2005 when EPA issued the mercury rule, which set a 69% cut in emissions of the metal sometime after 2018.
But now, the technology is in use at 25 utility boilers in four states that recently required coal-fired power plants to cut mercury emissions: Connecticut, Delaware, Massachusetts, and New Jersey. Plus, it has been demonstrated successfully in 50 Department of Energy and industry tests on the three main types of coal burned commercially and on boiler configurations found at nearly 75% of plants that burn this fuel, GAO found.
GAO estimates that installation of sorbent injection technology at all U.S. coal-fired power plants would cost 0.12 cents per kWh. In turn, this would increase the electricity bill of the average U.S. household by 97 cents per month.
In the meantime, EPA intends to require power plants to provide the agency with detailed information about their emissions of mercury, dioxins, and other hazardous air pollutants, McCarthy said. The agency will use these data as it develops the technology-based rule for mercury, she said. Plus, EPA is likely to use the information as it decides whether to tighten standards for other power plant pollutants, she added.
Although the new mercury rule may end up simply ordering each U.S. coal-fired power plant to install emission-reducing technology, EPA faces more complex issues as it works on a replacement for CAIR. Utilities favor a market-based cap-and-trade regime—as opposed to a requirement for pollution-control equipment on each unit—to lower emissions of NOx and SO2, as do many state regulators and a number of environmental groups.
But when the federal court threw out CAIR, it faulted the rule’s regional cap-and-trade system for NOx and SO2. The court, siding with an argument by the State of North Carolina, said the trading system failed to address air quality problems faced by states downwind of power plants outside their borders. Theoretically, utilities in a state upwind of North Carolina could buy allowances instead of cleaning up. This, the court said, would unfairly leave North Carolina stuck with dirty air—and out of compliance with federal standards—even if all utilities in the Tar Heel State curbed their pollution.
To address this thorny issue, EPA is considering an approach that blends emission standards at individual coal-fired units with a trading system, McCarthy said. The new tactic, she said, would guarantee that each downwind state struggling to meet the national ozone or particles air quality standard would get “the reductions it is entitled to.”
Notwithstanding EPA’s efforts, Carper said he and Sen. Lamar Alexander (R-Tenn.) plan in the coming weeks to introduce a bill to control SO2 and NOx from all coal-fired power plants in the U.S. through a trading system. The measure would also require each facility to reduce its mercury emissions.
“I have faith the EPA can write new and stronger rules to regulate these pollutants,” Carper said at the hearing. “But I’m afraid such regulations will be mired in the courts for years to come.”
A Carper aide says the senator hopes that a three-pollutant bill will get rolled into the climate-change legislation that is expected to wend its way through the Senate in the coming months.
Meanwhile, two Senate Republicans plan to introduce a bill that they say would give EPA the legal authority to use CAIR without rewriting the rule. They are Sen. James Inhofe of Oklahoma, the top Republican on the Senate Environment & Public Works Committee, and Sen. George V. Voinovich (R-Ohio).
“I would prefer comprehensive legislation to address power plant pollution,” Inhofe says. But such reform “in the near term is not politically feasible,” he adds.
Currently, the Senate Environment & Public Works Committee’s main focus is climate change. The panel is deep into a series of hearings on the issue. It remains unclear whether Sen. Barbara Boxer (D-Calif.), who chairs the committee, will back efforts to fold the power plant air pollution issues into whatever climate-change legislation emerges in the Senate. She likely will determine the fate of the Carper-Alexander and Inhofe-Voinovich bills.
Environmentalists are closely watching the situation but haven’t weighed in yet. Activists expect the replacement rules EPA is drafting will tightly ratchet down utilities’ pollution, says Frank O’Donnell, president of Clean Air Watch. He adds, “Legislation will probably have to do more—and do it more quickly—if it’s worth the bother.”
- Chemical & Engineering News
- ISSN 0009-2347
- Copyright © American Chemical Society