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1.0 Background and Overview of the Federal Regional Haze Regulation

1.1 Haze Characteristics and Effects

Haze refers to the presence of light-inhibiting pollutants in the atmosphere. These particles and gases scatter or absorb light to cause a net effect referred to as "light extinction." This scattering and absorbing occur across the sight path of an observer, thus leading to a hazy condition. Emissions of pollutants such as particulate matter, especially fine particulate matter (particles with a diameter less than 2.5 microns in size), sulfur dioxide, and nitrogen oxides are the primary contributors to visibility problems. Particulate matter can be emitted directly from stationary sources, or comprised in part of nitrate and sulfate particles formed through reactions involving nitrogen oxides and sulfur dioxide in the atmosphere. These constituents of haze are capable of being transported great distances while in the atmosphere. Due to this, sources may contribute to visibility impairment in Class I areas far downwind of their location, requiring a regional solution to the haze problem.

Reduction in visibility-impairing pollutant emissions such as nitrogen oxides (a precursor to ground-level ozone formation) also lead to a reduction in ozone. Ozone can diminish the ability for plants to produce and store food, making them more susceptible to disease, cause crop yield and forest growth to decline, and result in damage to leaves and trees in urban or other recreational areas. Nitrogen oxides and sulfur dioxide can both lead to acid rain, which damages forests and crops, acidifies waterways, and, long-term, alters the natural variety of plant and animal life in an ecosystem. In the Adirondack Mountains of New York State, mineral acidification from atmospheric deposition is responsible for ecosystem damage, including loss of fish populations. A major effect of acid rain on forest health and productivity is a reduction in the available supply of calcium and other base cations (positively charged ions) in soil that are needed for forest growth. The Catskill Mountain region of New York State has among the highest rates of sulfur and nitrogen deposition in the state and the lowest values for soil calcium availability. Significantly, the forested watersheds of the Catskill region provide the New York City water supply.

The inherent reduction of visibility-impairing pollutant emissions will also be protective of public health. While the presence of particulate matter is among the major causes of regional haze, ongoing studies reveal its contribution to a number of health issues, including respiratory irritation; decreased lung function; development or aggravation of respiratory conditions such as bronchitis; irregular heartbeat; and premature mortality. Ozone formed from nitrogen oxide emissions, along with sulfur dioxide and sulfate particles, causes similar respiratory impairment, especially among children whose respiratory systems are still developing, the elderly, and adults who are active outdoors. By regulating sulfur dioxide, nitrogen oxides and particulate matter, severe respiratory and cardiovascular diseases can be avoided. Reducing nitrogen oxides, an ozone precursor, is of great importance for New York State, which contains multiple areas which are classified as being in nonattainment of the ozone National Ambient Air Quality Standards (NAAQS). New York State also contains a fine particulate matter nonattainment area. Particulate matter consists of microscopic solid or liquid particles and is the major cause of the regional haze issue. Finally, the Department believes that improved visibility will lead to economic and tourism benefits in, for example, the "forever wild" areas in the Adirondacks.

1.2 General Background / History of Federal Regional Haze Rule

In amendments to the Clean Air Act (CAA) in 1977, Congress added Section 169 (42 U.S.C. 7491) setting forth the following national visibility goal:

Congress hereby declares as a national goal the prevention of any future, and the remedying of any existing, impairment of visibility in mandatory Class I Federal areas which impairment results from man-made air pollution.

Over the following years, modest steps were taken to address the visibility problems in Class I areas. In the time since the CAA was passed, progressively worsening conditions have been witnessed in the nation's Class I areas. The control measures taken mainly addressed plume blight from specific pollution sources, and did little to address regional haze issues in the Eastern United States. In fact, visibility in eastern parks has declined by as much as 83 percent [].

When the CAA was amended in 1990, Congress added Section 169B (42 U.S.C. 7492), authorizing further research and regular assessments of the progress made so far. In 1993, the National Academy of Sciences concluded that "current scientific knowledge is adequate and control technologies are available for taking regulatory action to improve and protect visibility."1

The EPA's Regional Haze Rule was adopted on July 1, 1999, and went into effect on August 30, 1999. The Regional Haze Rule's aim was to achieve national visibility goals by 2064. This rulemaking addressed the combined visibility effects of various pollution sources over a wide geographic region. This wide reaching pollution net means that many states - even those like New York without Class I areas - are required to participate in haze reduction efforts. The EPA designated five Regional Planning Organizations (RPOs) to assist with the coordination and cooperation needed to address the haze issue. The Mid-Atlantic / Northeast states, including the District of Columbia, were designated as part of the Mid-Atlantic / Northeast Visibility Union (MANE-VU).2

The EPA's adoption of the Regional Haze Rule was not without controversy. On May 24, 2002, the US Court of Appeals, D.C. District Court ruled on the challenge brought by the American Corn Growers Association against the EPA's Regional Haze Rule of 1999, 64 FR 35714. The Court remanded the BART provisions of the rule to the EPA, and denied industry's challenge to the haze rule goals of natural visibility and no degradation requirements. On June 15, 2005, the EPA finalized a rule addressing the Court's remand. The final BART Rule, 70 FR 39104, was published on July 6, 2005.

1.3 Area of Influence for MANE-VU Class I Areas

New York State contains no Class I Areas. However, as required by the haze rule, states that contribute to visibility impairment in Class I areas in other states must be identified and measures taken to reduce the emissions of visibility-impairing pollutants. In order to identify states where emissions are most likely to influence visibility in MANE-VU Class I areas, MANE-VU prepared the Contributions to Regional Haze in the Northeast and Mid-Atlantic United States in Appendix A. Based on this analysis, MANE-VU concluded that it was appropriate to define an area of influence including all of the states participating in MANE-VU plus other states that modeling indicated contributed at least 2% of the sulfate ion at MANE-VU Class I areas in 2002. These states are shown in Table 1-1 below. The 2% was arrived at after a review of the back trajectory and modeling results showing that states contributing 2% (or more) make up about 90-95% "of total light extinction. For states contributing 5% (or more), only about 75-80% of total light extinction is accounted for. New York agrees with the 2% criteria, given the high percentage of light extinction for which it accounts. New York believes that the 2% criteria represents a level of contribution for visibility impairment from any state that needs to be assessed for mitigation. Failure to do so will result in Class I areas failing to reach their reasonable progress goals and ultimately delay needed improvements in air quality.

Table 1-1 - States That Contribute to Visibility Impairment
in the MANE-VU Class I Areas of
Acadia, Moosehorn, Great Gulf, Lye Brook and Brigantine
State RPO State RPO
Connecticut MANE-VU North Carolina VISTAS
Delaware MANE-VU South Carolina VISTAS
Maine MANE-VU Tennessee VISTAS
Maryland MANE-VU Virginia VISTAS
Massachusetts MANE-VU West Virginia VISTAS
New Hampshire MANE-VU Illinois MRPO
New Jersey MANE-VU Indiana MRPO
New York MANE-VU Michigan MRPO
Pennsylvania MANE-VU Ohio MRPO
Rhode Island MANE-VU New Brunswick, Canada N/A
Vermont MANE-VU Ontario, Canada N/A
Georgia VISTAS Quebec, Canada N/A
Kentucky VISTAS

1.4 Class I Areas Affected

In accordance with 40 CFR Section 51.308(d)(4)(iii), emissions sources within the State of New York contribute to visibility impairment in the following Class I Areas:

Acadia National Park, Maine
Brigantine Wildlife Refuge, New Jersey
Great Gulf Wilderness Area, New Hampshire
Lye Brook Wilderness Area, Vermont
Moosehorn National Wildlife Refuge, Maine
Presidential Range-Dry River Wilderness Area, New Hampshire
Roosevelt-Campobello International Park, Maine/Canada
Shenandoah National Park, Virginia

The effect of New York's emissions and the measures that will be necessary to meet the goals of the Regional Haze program in the above areas are the focus of this document.

Information about procedures by which monitoring data and other information were used in determining the contribution of emissions from within these States to regional haze visibility impairment at MANE-VU Class I areas is included in Appendix A, Contributions to Regional Haze in the Northeast and Mid-Atlantic United States.


1 Protecting Visibility in National Parks and Wilderness Areas. National Research Council. Washington, DC: 1993
2 A description of MANE-VU and a full list of its members is found in Section 3 of this document.

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