Capitol Comment 187 - Smoggy Science: The Truth Behind Ozone Transport

Urban ozone smog has declined nationwide for over a decade, with particularly strong gains in the Northeast (see chart1). Despite such improvements in air quality, the standard for ozone has been tightened, escalating fears among many states that increasing controls on local sources of ozone smog will fail to achieve compliance. To allay these fears, the Environmental Protection Agency (EPA) has proposed a controversial regional control strategy that focuses on “downwind” emissions from coal burning utilities in the Midwest, claiming that these sources, through ozone transport, contribute significantly to ozone levels in Northeastern states.

Ozone transport: fact or fiction? Ozone smog — created when nitrogen oxides and volatile organic compounds react in the presence of sunlight — is known to traverse state lines within Northeastern states. However, long-range ozone transport, the idea that significant levels of ozone travel hundreds of miles away from its source only to later rain down on urban areas, remains a construct of mathematical models that has yet to be proven by actual data.

Nonetheless, Northeastern states, either convinced of the reality of ozone transport or seeking to shift the burden of their own pollution problems, have joined the EPA in an effort to tighten emissions of Midwest power plants by filing a petition under the Clean Air Act. If granted, the petition would allow the EPA to directly regulate hundreds of individual sources of chemicals called precursors that contribute to ozone formation. In addition, the EPA has proposed a controversial new rule designed to limit oxides of nitrogen (NOx), a key ozone precursor, in 22 states in the eastern “transport region,” an extensive area encompassing many parts of the Midwest, Northeast, and Southeast.2

Will the EPA’s new regional control strategy increase attainment of the new standard? The EPA rule is closely tied to the newly tightened air quality standard for ozone. The agency told the states that the proposed ozone transport rule, “should be enough to allow most of the new nonattainment counties in States covered by this rulemaking to be able to comply with the new standard.”3

However, a recent analysis of the rule based on research from EPA scientists and the Ozone Transport Assessment Group (OTAG), which is comprised of environmental officials from 37 states in the eastern half of the country, found that the regional strategy will save only two areas in the Northeast from the bite of the agency’s tighter new standard for ozone.4 Further, a report from OTAG found that ozone transport is most significant only up to approximately 150 miles from the source of NOx precursors. Thus, it is very unlikely that Ohio and Illinois contribute significantly to the smog problems of New York and Philadelphia,5 or that the EPA’s plan will improve air quality in states as far away as Maine and Vermont.

Did the states really support the EPA’s regional strategy? In order to buttress its case for regulation, the agency falsely claims OTAG voted in support of the regional strategy. However, the assessment group never reached a consensus on the issue. Indeed, the final OTAG report called only for more research before moving ahead with any controls.6 But, as usual, the EPA is refusing to listen to the states and its own scientists, moving ahead with a NOx cap it says will cost $1.37 billion annually in 2007.7 Other economists claim the cost is closer to $2.5 to $3.7 billion annually.8

The EPA’s failure to acknowledge its own science has some in Congress up in arms. A bill, H.R. 3690, recently introduced by Rep. Robert Wise (D-WV) would give states at least seven years to meet the requirements of the EPA’s ozone transport proposal, and requires the EPA to give states an additional year (from the date of enactment) to perform more research on ozone transport. The EPA would also have to wait until one year after the research is published in the Federal Register to promulgate the rule. The bill also postpones the rule’s actual implementation until five years after promulgation. Lastly, the bill prohibits the EPA from reaching a decision concerning the Clean Air Act petitions from the Northeast states until 180 days after promulgation of the ozone transport rule.

Conclusion. The ozone transport rule is proof that a disturbing trend has emerged in the way the EPA interprets environmental science. Once again, the EPA is ignoring the scientific evidence presented by its own scientists, while falsely characterizing OTAG’s position. Thus, the proposed rule and the Northeast’s petition remain indefensible.

1Kay Jones and Jonathan Adler, “Time to Reopen the Clean Air Act; Clearing Away the Regulatory Smog,” Cato Institute Policy Analysis, #233, July 1995; 1994-1996 data updated by Zephyr Consulting.

2Federal Register, November 7, 1997, Volume 62, Number 216, pp. 60317-60367; States affected by the rule would include Alabama, Connecticut, Delaware, Georgia, Illinois, Indiana, Kentucky, Massachusetts, Maryland, Michigan, Missouri, North Carolina, New Jersey, New York, Ohio, Pennsylvania, Rhode Island, South Carolina, Tennessee, Virginia, West Virginia, and Wisconsin.

3Ibid.

4Kay Jones and Joel Bucher, “Will Reducing Ozone Transport Improve Regulatory Compliance?” Forthcoming article in Environmental Management.

5Rudolf B. Husar and Wandrille P. Renard, “Ozone as a Function of Local Wind Speed and Direction: Evidence of Local and Regional Transport,” Center for Air Pollution Impact and Trend Analysis, http://capita.wustl.edu/OTAG/reports/otagwind/ OTAGWIN4.html, July 26, 1997.

6″Did the Midwest Win the OTAG War?” Electricity Daily, October 10, 1997, Vol. 9, No. 72.

7″EPA Forges Ahead With Trading Plan in Face of Criticism, Uncertainties,” Daily Report for Executives, Monday May 11, 1998.

8Tom Hewson, “How Much More? Evaluation of Three Proposed NOx Control Programs for Utilities in 37 State OTAG Region,” Energy Ventures Analysis prepared for Midwest Ozone Group, pp. 17-18, May 1997.