Banishing summertime smog from Baltimore and the rest of the Northeast will require a far greater reduction of pollution by electric power plants and industry than envisioned by lawmakers and regulators, a new federal study shows.
Government efforts to curb smog so far have focused on only one of the two types of pollutants that form ground-level ozone, the chief component in smog.
However, it may be far more important to control the other chemical ingredient of ozone, according to computer projections by the U.S. Environmental Protection Agency (EPA). The information is to be presented today to a meeting in Portland, Maine, of air-quality regulators from 12 Northeastern states, including Maryland.
Ozone is formed when hydrocarbons, released in great quantities by motor vehicles, combine under the hot sun with nitrogen oxides, released mainly from power plants and by industry as well as by vehicles.
The EPA's computer projections indicate that the states may have to reduce nitrogen oxides by 75 percent, while cutting hydrocarbons only 25 percent in order to eliminate smog from much of the Northeast.
Ozone causes breathing problems for many people during the summer. Air quality has improved since 1989, largely because of cooler weather, but the Baltimore area still suffers from a severe ozone problem. Smog also remains serious in the Washington area and Cecil County, the EPA said yesterday.
More than 4 million Marylanders breathe unhealthful amounts of ozone at least occasionally during the summer, state officials estimate.
Congress amended the Clean Air Act in 1990 to require that smoggy urban areas make specific reductions in hydrocarbons.
But the law did not set similar targets for ozone's other ingredient, nitrogen oxides.
Baltimore and its suburbs, for instance, must reduce hydrocarbon emissions 15 percent by 1996 and 3 percent each year thereafter until ozone no longer reaches unhealthful levels.
To curb hydrocarbons, federal and state regulators have moved to require cleaner burning gasoline, gasoline nozzles at service stations that can capture fuel vapors and cleaner burning cars and trucks. Maryland and other Northeastern states have pledged to adopt California's tailpipe-emission standards, which are more stringent than federal law requires.
The Clean Air Act requires "reasonably available" controls on nitrogen oxides to curb smog.
Further analysis will be needed to determine how much of each (( pollutant will have to be curbed by each state to reach acceptable air-quality levels, said Bruce Carhart, executive director of the Ozone Transport Commission, the panel of
Northeastern air-quality officials.
In Maryland, 56 percent of the nitrogen oxides come from power plants and industry, 33 percent from motor vehicles, and 11 percent from a variety of other small sources.
Maryland last week proposed rules that would require about 70 power plants and factories in the state to switch to cleaner burners or take other measures to curb nitrogen oxides by May 1995.
The state's proposed rules are just a first step, said Susan Wierman, acting air management director for the state Department of the Environment.
The state projects that the rules will cost the affected industries $150 million to $230 million, with most of the burden falling on electric utilities. Power companies will have to switch to cleaner burners in coal-fired plants.
The rules could mean a boost of about 60 cents a month on the aver age household electric bill in central Maryland. Baltimore Gas and Electric Co., which supplies power to the region, estimates it will have to spend about $40 million to comply.
Switching to cleaner burners, as required by the proposed rules, will reduce nitrogen oxide emissions about 24 percent, estimated David W. Parks, BG&E;'s clean-air issues manager.
Making even greater reductions could cost the utility up to $400 million, which would mean an increase of $2.40 a month on the average homeowner's electric bill. That would entail putting on the most advanced pollution controls available, he said.