Areas Designated Nonattainment for PM2.5 Could Increase Significantly under Proposed EPA Air Quality Standards

On December 20, 2005, EPA issued proposed amendments to the primary and secondary National Ambient Air Quality Standards (“NAAQS”) for particulate matter. See, 71 Fed. Reg. 2620 (Jan. 20, 2006). The NAAQS are the cornerstone of the Clean Air Act. 42 U.S.C. § 7409. Primary standards specify limits on the concentration of air pollutants in the ambient air that are adequate to protect public health, with a margin of safety. 42 U.S.C. § 7409(b)(1). Secondary standards, which are the same as or more stringent than the primary standards, specify limits intended to protect the public welfare from known or anticipated adverse effects including effects on agriculture, property, aesthetics and visibility. 42 U.S.C. § 7409(b)(2). “Particulate matter” (PM) includes both solid particles and liquid droplets found in the air. PM may be emitted directly from sources or may be formed when other pollutants emitted into the atmosphere react. PM less than 10 micrometers in diameter (PM 10) is a potential health concern because it may be inhaled into the respiratory system and accumulated. Fine particles less than 2.5 micrometers in diameter (PM 2.5) are of particular concern, because they can lodge deeply into the lungs. Studies have associated fine particulate matter with respiratory and cardiovascular problems, including aggravated asthma, irregular heartbeats, heart attacks, and early death in people with heart or lung disease. Particle pollution also is known to contribute to visibility impairment. For more information about PM, see http://www.epa.gov/ttn/naaqs/pm/pm25_index.html and http://www.epa.gov/oar/particlepollution/health.html.

Proposed NAAQS for Fine Particles

The primary NAAQS for PM 2.5 or fine particles, which have been in place since 1997, include a 24-hour standard of 65 micrograms per cubic meter (µg/m3) and an annual standard of 15 µg/m3. Under the proposed revisions, the 24-hour standard for fine particles would be reduced to 35 µg/m3. The annual PM 2.5 standard of 15 µg/m3 would not be changed. EPA proposes that the secondary standards be the same as the primary standards. 71 Fed. Reg. 2620, 2698-99 (Jan. 20, 2006).

Proposed NAAQS for Inhalable Coarse Particles

The NAAQS for “coarse” particles or PM 10, which have been in place since 1987, include a 24-hour standard of 150 µg/m3 and an annual standard of 50 µg/m3. EPA revised these standards in 1997 along with the fine particulate matter standards. However, EPA vacated the 1997 revisions to the PM 10 standards when the United States Court of Appeals for the D.C. Circuit directed EPA to ensure that the regulations for coarse particles did not duplicate regulations for fine particles. American Trucking Ass’n v. EPA, 175 F.3d 1027, (D.C. Cir. 1999), reh’g granted in part and denied in part, 195 F.3d 4 (D.C. Cir. 1999), aff’d in part and rev’d in part, Whitman v. American Trucking Association, 531 U.S. 457 (2001). In response to that decision, the proposed amendments change the definitions to regulate “inhalable coarse particles”, which are particles between 2.5 and 10 micrometers (PM 10-2.5). Specifically, EPA proposes a 24-hour standard of 70 micrograms per cubic meter for PM 10-2.5. This standard would apply to airborne mixes of coarse particles originating from sources that pose the greatest risk to public health. This includes high-density traffic on paved roads and industry sources. The proposed standard would not apply to mixes of coarse particles that EPA has found do not pose a significant risk to public health, such as windblown dust and soils and agricultural and mining sources. The proposed rule does not include an annual standard for PM 10-2.5. Also, EPA proposes that the secondary standards be the same as the primary standards. 71 Fed. Reg. 2620, 2698-99 (Jan. 20, 2006).

Comments on Proposed Standards

In addition to the standards expressly proposed in the proposed rule amendments, EPA also has requested comments on whether a range of annual and 24-hour standards for fine particles should be made more stringent or whether they should be left at their present levels.

EPA’s Clean Air Scientific Advisory Committee (“CASAC”), an independent scientific advisory committee comprised of seven members appointed by EPA and established under the Clean Air Act, announced its intent to convene a teleconference on February 3, 2006 in order for CASAC to consider providing additional comments to EPA regarding its proposed rule. According to CASAC’s announcement of the teleconference, the meeting is “a continuation of the CASAC PM Review Panel's ongoing advisory activities in this present NAAQS review cycle for particulate matter.” 71 Fed. Reg. 2924 (January 18, 2005).

Potential Designation of Additional Areas of Nonattainment

Areas that are currently designated nonattainment for PM 2.5 are located primarily in portions of California and the East Coast. The number of areas designated nonattainment for PM2.5 could increase significantly if the new standard is adopted. EPA White Paper Preliminary Analysis of Proposed PM 2.5 NAAQS Alternatives(December , 2005), available at http://www.epa.gov/air/particles/pdfs/whitepaper20051220.pdf. Based upon 2002-2004 data, EPA has identified areas that exceed the proposed NAAQS for PM 2.5 in Washington, Oregon, Idaho, Montana, Utah and California, as well as facilities in the Midwest and East Coast. Id. EPA will not designate areas of nonattainment under the new standards based on this data, and expects that more recent and future data will show improved air quality. Id.

PM pollution varies by time of year and location, and may be caused by many different sources. Primary PM is directly emitted into the atmosphere from cars, trucks, heavy equipment, forest fires, burning waste, coke ovens, coal combustion and industrial processes. Id. at p. 16. Secondary PM is formed indirectly from fuel combustion and other sources. Id. As a result, there are many different strategies that states use for controlling PM. In Washington State, for example, one of the leading causes of PM pollution is wood and waste burning. As a result, the air districts in Washington strictly limit open burning, and burning of wood and waste. See, e.g. Puget Sound Clean Air Agency Regulation 1, Article 8 (Outdoor Burning). The agencies also have initiated a program to reduce diesel emissions from vehicles earlier than already required by EPA programs. Under the “Diesel Solutions” program, the Puget Sound Clean Air Agency is encouraging increased use of ultra-low sulfur diesel fuels with diesel particulate filters to reduce fine particle emissions by more than 90 percent (in addition to reducing toxic emissions and hydrocarbon emissions). See http://www.pscleanair.org/dieselsolutions/index.shtml.

Along with the proposed rule, EPA issued its Interim Regulatory Impact Analysis for the Proposed NAAQS for PM. The analysis reviewed the costs and benefits of attaining the proposed new PM standards in Atlanta, Chicago, New York, Philadelphia and Seattle. According to the analysis, the benefits would outweigh or be the same as the costs in some areas, but would be less than the costs in other areas. In Seattle, the study found that the proposed standards could be met by 2015 with additional locally imposed controls, including the installation of scrubbers or baghouses at fine particulate emission sources and the installation of emissions controls on diesel school buses. The study estimates that health benefits in Seattle would be between $540 million and $450 million, while costs of controls would be between $750 million and $770 million. For the full analysis, see http://www.epa.gov/air/particles/actions.html.

EPA must finalize revised PM standards by September 2006 and should issue final designations for PM 10-2.5 by 2013.

Related Actions

Along with the proposed amendments, EPA Deputy Administrator Marcus Peacock issued a memorandum requesting the formation of a working group for a “top-to-bottom” review of EPA’s process for setting NAAQS. The intent of the memorandum is to determine how the process can be expedited and improved. In a January 18, letter to the Deputy Administrator, the American Lung Association, Clean Air Watch, Clean Air Task Force, Environmental Defense, the National Environmental Trust, and the National Parks Conservation Association requested that more time be provided for the “top-to-bottom” review in order to allow for full public comment. 37 Env. Rptr. 4 (Jan. 27, 2006).

For a copy of the proposed rule amending the NAAQS for particulate matter, see http://frwebgate3.access.gpo.gov/cgi-bin/waisgate.cgi?WAISdocID=78973019643+1+0+0&WAISaction=retrieve.