WASHINGTON — Congress is feuding over how quickly the federal government should move in trying to reduce deadly air pollution that comes from industrial boilers and incinerators.

The issue has aroused much controversy in Washington state and elsewhere in the Pacific Northwest, where the forest products industry is big business, fueled by the use of its byproducts to power biomass boilers, which run on plant material and animal waste.

Fears persist among many — Republicans and Democrats alike — that the federal government will go too far in hurting the region’s economy by imposing new regulations that could result in mass layoffs.

The GOP-led House of Representatives voted nearly two weeks ago to force the Environmental Protection Agency to wait another 15 months before imposing new regulations on all types of boilers. The House plan would give companies five years to install equipment to capture more pollution, including mercury and lead.

Environmental groups oppose a delay. They say it could result in thousands of unnecessary deaths.

Across the nation, biomass boilers have become increasingly controversial as environmentalists question their safety and increased level of greenhouse gas emissions.

Last year, a study by the Environmental Working Group, a nonprofit advocacy organization, urged that all state and federal subsidies for biomass be scrapped, saying the small amount of power generated by biomass plants isn’t worth the risk to the environment.

Members of the Washington state delegation have been particularly active in the debate on Capitol Hill in recent weeks.

Calling the plan to delay the regulations “a no-cost jobs bill,” freshman Republican Rep. Jaime Herrera Beutler said that if Congress failed to act, pulp mills, paper mills and others that couldn’t afford to upgrade their boilers “will all shed … thousands of jobs” in her district in southwest Washington state.

Reflecting the issue’s sensitivity in the Northwest, Democratic Sen. Ron Wyden of Oregon joined a bipartisan group in July in proposing to put the brakes on the EPA, saying its new rules would “stymie the burgeoning biomass energy industry and make it very difficult for existing lumber and wood products mills to operate.”

Washington’s biomass

Much is at stake for Washington state, one of the nation’s largest producers of biomass power.

With millions of dollars in subsidies and federal grants, at least a dozen biomass plants in the state are producing power from wood byproducts from mills and waste from forests.

One of them, Simpson Tacoma Kraft Co., a forest products company in Tacoma, Wash., generates electricity by boiling water to burn sawdust, bark and wood shavings from pulp mills and sawmills, sending the high-pressure steam into a turbine. The company declined to comment on the legislation.

Despite the sympathy for the biomass companies, the effort to delay the EPA rules faces a stiff fight, with environmental groups leading the charge against the legislation.

At the Natural Resources Defense Council, John Walke, the group’s clean air director, called the plan “the latest installment of the tea party’s unraveling of the Clean Air Act.” He said the plan that passed the House would “sacrifice tens of thousands of lives, pollute the air we breathe and expose our children, families and communities to toxic air pollutants.”

In a report issued earlier this year, the Congressional Research Service said the EPA rules would affect more than 13,000 boilers around the nation, most of them — about 85 percent — fueled by natural gas.

The report said companies would incur capital costs of less than $7,000 to upgrade a natural gas-powered boiler. It said costs would be higher for coal-fired and biomass-fired boilers, which might need to install fabric filters to control mercury and other contaminants. The report estimated that there are 420 biomass-fueled boilers in the country.

According to the EPA, implementing the new regulations, beginning in 2013, would prevent 1,900 to 4,800 premature deaths a year, along with 1,300 cases of chronic bronchitis, 3,000 nonfatal heart attacks and 33,000 cases of aggravated asthma, among other things.

The EPA also said the new regulations would reduce national emissions by 7 percent, including 15,000 pounds of mercury each year.

At the White House, President Barack Obama’s top advisers are siding with environmental groups, urging a veto if Congress approves the delay.

In the Senate, California Democrat Barbara Boxer, who heads the Environment and Public Works Committee, is leading an effort to kill the plan when it comes up for a vote there.

Earlier this month, Boxer’s committee issued a report that said delaying the EPA rules would “sacrifice the enormous public health and economic benefits of the new safeguards.”