The EPA’s recent action to curb nitrogen oxide emissions from 22 states should keep about 8 million pounds of nitrogen a year out of the Bay when the action is fully implemented in 2003, according to a new report.

That’s equal to about 11 percent of the Bay Program’s 71 million pound nitrogen reduction goal.

In an action now being challenged by an industry group and several states, the EPA ordered parceled out specific NOx reductions totaling 1.1 million tons — or 28 percent — to 22 states in late September.

The action — known as a “SIP [State Implementation Plan] Call” — was aimed at reducing chronic summertime smog that blankets many cities, particularly along the East Coast.

It was the agency’s first action to force air pollution reductions on upwind states to improve downwind air quality. Once emitted, NOx can drift hundreds of miles downwind, where it can help form ground-level ozone — the key ingredient of summertime smog — or contribute to algae blooms in estuaries and coastal waters.

Coastwide, the action would keep 39.6 million pounds of nitrogen out of estuaries all along the East Coast and out of Sarasota and Tampa bays on Florida’s Gulf Coast, according to the EPA report, “The Regional NOx SIP Call & reduced Atmospheric Deposition of Nitrogen: Benefits to Selected Estuaries.”

The report estimated that the air pollution control effort was worth about $34 million a year to the Bay watershed. That, according to the report, is what it would cost to install and maintain a likely “mix” of activities to control a similar amount of nitrogen running off the watershed. Coastwide, it calculated the total benefit at $237 million a year.

About 25 percent of all the nitrogen that reaches the Chesapeake stems from air pollution.

The EPA’s action was particularly helpful to the Bay because some of the sharpest reductions are required from Midwestern states immediately upwind of the Bay watershed. Computer models show that the majority of the airborne nitrogen reaching the Bay originates from outside its 64,000-square mile basin but within a surrounding 350,000-square-mile “airshed.”

The SIP-Call was one of a series of actions taken by the EPA lately to reduce NOx emissions, primarily to help control ground-level ozone and the emission of tiny particles, both of which causes a variety of human health problems.

When all those programs are fully in place — something that won’t happen until after 2010 — they will reduce the amount of nitrogen entering the Bay by 10 million to 15 million pounds a year, according to estimates made by the Bay Program. [See “New rules offer downwind states a whiff of fresh air, BAY JOURNAL November 1998.

The earlier Bay Program estimates, though, did not separate out the reductions attributed only to the new 22-state order, which mostly affects utility power plants.

But that rule is being challenged by the Midwest Ozone Group, a coalition of utility and fuel companies, which filed a petition in U.S. Circuit Court of Appeals in Washington in early November.

An attorney for the group, David Flannery, said the rule places unfair burdens on utilities and that the EPA did not look at alternatives.

Also, the state of Michigan filed an appeal, and the West Virginia Department of Environmental Protection said it intended to file one.

The EPA has estimated its action would be about $17 billion, but critics say it will cost far more.

“There are going to be massive job losses if this thing is implemented and the cost of electricity is affected the way this thing will,” Flannery said.

A study by the EPA says the clean air rules will lead to a net increase of about 1,150 jobs in states affected by the regulations.

That does not include short-term jobs that would be created to install pollution control equipment.

That figure includes a loss of about 430 coal mining jobs in the United States by 2007.

The EPA also predicts that 600 jobs would be created in natural gas production and 985 full-time workers would be hired to maintain equipment installed on industrial boilers and power plants.

— The Associated Press contributed to this report