Scientific Report Faults EPA for New Source Review Rule Changes

WASHINGTON, DC, July 24, 2006 (ENS) - The U.S. Environmental Protection Agency should use a broader, more comprehensive approach to evaluate changes to the New Source Review part of the Clean Air Act, finds a new report from the National Research Council. The New Source Review measures govern large, stationary sources of air pollution such as factories and power plants.

Released Friday, the report finds that the nation's air would be cleaner if the original Clean Air Act is followed than if the EPA's changes are adopted.

In 2002 and 2003 the EPA made changes to New Source Review that, among other things, expanded the range of modifications a facility can make without getting a permit.

The agency and other supporters predicted that the revisions would not result in significant changes in emissions and would give industry more flexibility to modernize plants and improve energy efficiency.

Opponents warned that the revisions would slow progress in cleaning the nation's air and result in damage to human health. Because of the controversy, Congress asked the National Research Council (NRC) to estimate the revisions' effects.

A private, nonprofit institution that provides science advice under congressional charter, the National Research Council is the main operating arm of the National Academy of Sciences.

The NRC panel tasked with evaluating the EPA's changes concludes that the old "prerevision" New Source Review program achieves greater emission reductions than the agency's Equipment Replacement Provision rule.

The panel finds that even with the adoption of the agency's Clean Air Interstate Rule, pollution will likely increase in areas throughout the country.

The 17 member panel is chaired by Charles F. Stevens, a molecular neurobiologist based at the Salk Institute for Biological Studies in La Jolla, California, where he is the Vincent J. Coates Professor of Molecular Neurobiology and a Howard Hughes Medical Institute investigator. He also is a member of the National Academy of Sciences.


Molecular neurobiologist Charles F. Stevens chairs the Committee on Changes in New Source Review Programs for Stationary Sources of Air Pollutants of the National Research Council's Board on Environmental Studies and Toxicology in the Division on Earth and Life Studies. (Photo courtesy PittChronicle)
Although the report's analysis focuses on the likely effects of the EPA's 2002 and 2003 revisions to the rules – changes that have since, in large part, been struck down by federal courts – it can serve as a case study for how future revisions could be assessed, said the committee that wrote the report.

Under New Source Review, before a new facility can be built or an existing one modified, a permit must be obtained by showing that the new plant or equipment will not disrupt progress toward attaining air quality standards in an area, or significantly worsen air pollution in a location that already meets them. The applicant also must show that advanced emission control devices will be added to the plant.

It is impossible to quantify with certainty the changes' impact on emission levels, human health, or energy efficiency, because existing models have limitations and data so far are scarce, the Research Council's report says.

A portion of the 2002 revisions was struck down by a court last year, and the remainder has gone into effect in only a few states.

The 2003 revision, known as the Equipment Replacement Provision (ERP), has not been implemented because it was stayed by a court in 2004 and struck down earlier this year.

It would have allowed facilities to make certain equipment replacements without an New Source Review (NSR) permit even if pollutant emissions increase significantly, as long as the facility does not exceed its maximum level of allowable emissions. This expanded the scope of the exemption from NSR for routine maintenance.

The panel says the EPA should use computer modeling to provide some insights into the likely effects of changes to New Source Review rules before they are made.

Its analysis for this report estimates future national emissions of sulfur dioxide and nitrogen oxides from coal-fired power plants under the Equipment Replacement Provision and compares them with emissions levels that could be expected if pre-revision rules continued.

power plant

Cinergy Corp's Zimmer coal-burning power plant in Ohio is the largest single-unit fossil generating unit ever built. (Photo courtesy Stefan Schlöhmer)
The committee used the same model as EPA, but added different assumptions to account for other possible scenarios of how aggressively New Source Review might be enforced, other relevant regulations, and varying economic and technological conditions.

For example, EPA's analysis had assumed that if pre-revision rules continued, plants would avoid making modifications that would trigger New Source Review requirements – resulting in older, higher-emitting equipment operating longer without repair.

The new analysis, on the other hand, compares emissions under the Equipment Replacement Provision with another scenario, one in which pre-revision rules are enforced more aggressively and lead to more replacements of deteriorating equipment.

For sulfur dioxide, the Equipment Replacement Provision would be expected to result in a moderate decrease in emissions for the first six years or so, followed by a six-year period of little change, the committee's model shows.

But after 12 years the Equipment Replacement Provision would likely result in higher emissions, perhaps substantially so, compared with what would result if pre-revision rules continued, the committee said, assuming aggressive implementation of the pre-revision rules would have required all power plants to add emission controls by that point.

The Equipment Replacement Provision also would be expected to cause an increase in emissions of nitrogen oxides – again, possibly substantial – under certain circumstances after the first few years.

But the difference in emissions between pre-revision and revised rules would be lessened, the committee said, if EPA implements its 2005 Clean Air Interstate Rule (CAIR), a "cap-and-trade" program aimed at lowering emissions from power plants in Eastern and Midwestern states.

Such programs set limits on overall emissions in an area but allow individual plants to buy and sell pollution "allowances."

With the Clean Air Interstate Rule in place, differences in total sulfur dioxide emissions between pre-revision rules and Equipment Replacement Provision would be minor, the model suggests.

CAIR would also probably moderate an expected increase in nitrogen oxide emissions caused by Equipment Replacement Provision and delay it for a dozen years, for the scenario in which all facilities would otherwise have added emission controls under the pre-revision rules.

Because current models shed little light on the expected effects of the EPA's rule changes on particular plants and geographic locations and local populations with varying characteristics, no conclusions can be drawn about how the revisions would affect human health, the report says.

power plant

Allegheny Energy' Hatfield's Ferry coal-burning power plant in Pennsylvania has just been forced by a citizens' lawsuit to put scrubbers on its stacks to remove some pollutants from emissions. (Photo courtesy Allegheny Energy)
At a national level, a cap-and-trade program with caps below those specified by CAIR would be a more cost-effective approach to lowering emissions than aggressive regulation under New Source Review.

But again, the committee's analysis was limited because it could not assess specific, local emission changes and their impact on public health.

State and local air pollution control officials said the report "confirms fears that EPA's controversial new source review revisions will interfere with states' efforts to clean up the air."

S. William Becker, executive director of the State and Territorial Air Pollution Program Administrators and Association of Local Air Pollution Control Officials, said, "This is especially critical at a time when agencies are now developing plans to achieve and maintain health-based air quality standards for ozone and fine particulate matter."

The two national associations Becker heads represent air pollution control agencies in 53 states and territories and over 165 major metropolitan areas across the United States.

CAIR is clearly not a substitute for New Source Review, said Becker, because its deadlines are too protracted - 2015 and beyond - and its limits are too weak, far less stringent that New Source Review.

Becker points out that CAIR only affects utilities, not other industrial sources. In addition, it only applies to Eastern states - the West is exempt.

Finally, Becker says, CAIR only covers a limited number of pollutants - sufure dioxide and nitrogen oxides.

The National Research Council panel directs that models "must be improved to better account for how New Source Review and revisions to the rules affect individual plants' decisions about whether to install new equipment."

To assess health effects, future models will need to incorporate detailed meteorological information on the appropriate scale, such as regional or local, the panel recommends.

Better data collection also is needed to aid future analyses of the revisions' effects after they are implemented, the committee said.

The panel said EPA and state agencies should create and maintain a central database of permits issued under New Source Review, as well as minor permits issued by states, so that emissions from plants in states governed by the revised rules can be compared with those from plants operating under pre-revision rules.

Data should also be collected on plants' investments in pollution-control equipment and programs, to allow investigators to study whether the rule changes lead plants to invest more or less in these improvements.

The report, available online at:, was sponsored by the U.S. Environmental Protection Agency.