The report gives results of an extensive review and analysis of the literature aimed at: studying historical trends of particulate, SOx, and NOx emissions and of acid rain in the northeastern U.S.; studying size and composition of particulates from power plants; and analyzing interactions between particulates and sulfur-bearing gases from coal-fired power plants. Particulate mass emissions from industrial and combustion sources project a rising trend, nationwide, if no additional controls are assumed. (With application of best controls, the trend projection is reversed.) SO2 emissions have been increasing nationwide since 1950; without additional controls and with a 5% industry growth, this trend is expected to continue. (If new source performance standards and state implementation plans become effective in 1978, SO2 emissions are expected to decrease.) NOx mass emissions have increased consistently since 1920; those for 1970 were more than 3 times those for 1920. The limited data available for ambient NOx levels is further complicated by inherent limitations of measurement techniques used to obtain the data. Information on acid rain in northeastern U.S. is extremely scarce. Available data indicates that precipitation in this region has become increasingly acidic over the years. A better assessment of the trend can be made only when better rainwater pH information becomes available.

Prepared under contract no. 68-02-1324, task 44, ROAP no. 21ADL-029, program element no. 1ABO12. Issued Sept. 1976. Includes bibliographical references.