Quality Standards (NAAQS) and that pose potential threats to the health of 

 organisms (including people) and to the environment (NAAQS and the Clean Air 

 Act and its application to coastal Maine are described in appendix C) . In 

 addition, areas exist that are unclassified; the quality of their air is not 

 known. 



The Maine State Implementation Plan of 1979 identified (based on extant 

 ambient air quality data) those portions of the coastal zone that have not 

 attained safe levels of the five pollutants controlled by the Clean Air Act: 

 sulfur dioxide (SO2) , nitrogen oxides (N0 X ), carbon monoxide (CO), total 

 suspended particles (TSP) , and ozone (O3). Ozone represents a particularly 

 serious problem as the entire coastal zone has unsafe levels of it. Several 

 areas have unsafe levels of TSP and CO. Coastal Maine has been classified as 

 having safe levels of N0 X and unsafe levels of SO2. Maine suffers from acid 

 precipitation that is the result of long-distance transport of S02 and N0 X 

 from other areas. Parts of region 4 and all of regions 5 and 6 were 

 classified as "nonattainment" with regard to SO2 in 1977, because of large 

 amounts released in Millinocket, Maine (in violation of NAAQS). Regions 4, 5, 

 and 6 are currently in "attainment." Part of region 4 and all of regions 5 

 and 6 will be reclassified with regard to ozone. Due to lack of data and a 

 change in NAAQS standards for ozone this area will be classified as 

 "unclassif iable . " 



Attainment areas are classified by the EPA as class I, class II, or class III, 

 depending on the current quality of the air and the degree of deterioration to 

 be allowed for in these nondegradation areas. Maximum allowable increases in 

 ambient concentrations of pollutants have been set. Class I areas include all 

 national and international parks, national wilderness areas, and national 

 memorial parks >6000 acres (2429 ha). These areas are highly protected. All 

 other attainment areas in coastal Maine are class II. 



The individual statuses of the five criteria air pollutants controlled by the 

 Clean Air Act and the biological effects of air pollution in coastal Maine are 

 discussed below. 



Sulfur dioxide . Gaseous sulfur dioxide (SO2) is emitted primarily by 

 combustion in coal- and oil-burning power plants and to a lesser extent by 

 pulp mills and residential and commercial heat generators. Sulfur dioxide is 

 oxidized in the atmosphere to sulfuric acid, which is carried in precipitation 

 and causes rain water to be acidic. The mean residence time for sulfur in the 

 atmosphere is 2 to 4 days (Robinson and Robbins 1968). Consequently, SO 2 may 

 be transported more than 4375 miles (7000 km) before deposition occurs (Likens 

 and Bormann 1974) . Ecological damage to natural systems from acid rain has 

 been documented in New York, where many remote lakes have become devoid of 

 fish, due to low pH caused by acid rain. Similar problems were documented in 

 northern New England in 1979 (personal communication from T. Haines, U.S. Fish 

 and Wildlife Service, Orono, ME; December, 1979). Recent studies (Davis et 

 al. 1978; and Norton et al. 1978) indicate that transport of SO 2 into Maine, 

 from sources as far away as the Ohio Valley, is causing ecological 

 deterioration (acidification), particularly in lakes. 



The characterization area presently maintains an attainment rating for SO j- 

 State officials have indicated that total reduced sulfur, present in the air 

 as H2 S and other substances, is problematic chiefly due to its odor, and the 



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