Acid Rains Scientific evidence has shown that atmospheric deposition of sulfur and nitrogen compounds can harm ecosystems. Title IV of the Clean Air Act Amendments of 1990 (CAAA or the Act) addresses the problem of such effects by mandating reductions in emissions of sulfur and nitrogen oxides, the major precursors of acidic deposition. Coupled with Titles I and II of the Act, which address new and existing stationary and mobile sources of sulfur and nitrogen oxides, …showed first 75 words of 3579 total…

…showed last 75 words of 3579 total…be implemented. Further analysis is necessary to determine what level of ancillary benefits to human health, visibility, and material and cultural resources either approach would provide and the extent to which one approach provides greater benefits than the other. Title IV was designed to address regional air pollution problems, especially those involving long-range transport of pollutants and their transformation products. The likelihood of achieving deposition reductions is viewed as a critical factor in judging effectiveness.