could contribute to the increasing pollution of natural and man-made water systems;

could adversely affect agricultural and forest crops;

could adversely affect fish and wildlife and natural ecosystems generally;

could contribute to corrosion of metals, wood, paint, and masonry used in construction and ornamentation of buildings and public monuments;

could adversely affect public health and welfare; and

could affect areas distant from sources and thus involve issues of national and international policy.

to identify the causes and sources of acid precipitation;

to evaluate the environmental, social, and economic effects of acid precipitation; and

based on the results of the research program established by this subchapter and to the extent consistent with existing law, to take action to the extent necessary and practicable (A) to limit or eliminate the identified emissions which are sources of acid precipitation, and (B) to remedy or otherwise ameliorate the harmful effects which may result from acid precipitation.