Air Quality Projections for the Ohio River Basin

Abstract

The purpose of the OHIO River Basin Energy Study (ORBES) was to assess the potential environmental, social and economic impacts associated with the construction of additional power plants in the Ohio River Basin. The study area, as mandated by the U.S. Congress, included parts of the six states of Illinois, Indiana, Kentuckly, Ohio, West Virginia and Pennsylvania, The evaluation of air quality changes for different assumptions of electricity demand, regulatory constraints and power plant retirement schedules played an important role in this assessment. This paper presents estimates of future air quality in the ORBES region based upon dispersion model calculations and projected emissions. While SO₂ emissions are projected to generally decrease in the future years, along with regional background concentrations, there will be areas which will have problems meeting ambient air quality standards. For this reason, the paper also deals with the problems involved in the use of standard regulatory models for air quality planning in this high emission density area. The results presented here pertain only to the current and future emissions of sulfur dioxide (SO₂), which is the constraining pollutant in terms of the growth of new sources and the attainment of National Ambient Air Quality Standards (NAAQS). Emissions of S0₂ are also a factor in the formation of fine particulates, acia precipitation and regional visibility degradation.