(CN) - Grants for cleaning up old diesel engines have cut down air pollution that causes premature deaths and asthma attacks, the U.S. Environmental Protection Agency reported.
Handed to Congress on Wednesday, the report touts the 2008 Diesel Emission Reduction Act program as having retrofitted or replaced 73,000 diesel engines whose exhaust creates a significant amount of likely-carcinogenic soot and smog.
The program has greatly improved air quality for Americans and saved 450 million gallons of fuel, according to the report, the third of its kind.
Presenting the final results from the American Investment and Recovery Act of 2009, the report covers fiscal years 2009-11, and estimates the impacts from funding in fiscal years 2011-13.
Researchers credit the program with preventing 4.8 million tons of carbon dioxide emissions - essentially, the annual CO2 emissions from more than 900,000 cars.
The EPA says the program has cleaned up about 335,200 tons of nitrogen oxides and 14,700 tons of particulate matter, which has been linked to sometimes fatal respiratory ailments.
Researchers say the program prevented 18,900 tons of hydrocarbon and up to 1,700 premature deaths.
In all, the program generates up to $12.6 billion in monetized health benefits - i.e. up to $13 of public health benefit for every $1 spent on diesel projects - according to EPA estimates.
Thus far, a total of $570 million funds have been awarded through 642 grants.
"By cleaning up older diesel engines that generate air pollution, the EPA is protecting people's health and making a visible difference in communities throughout New York, New Jersey, Puerto Rico and the U.S. Virgin Islands," EPA Regional Administrator Judith Enck said in a statement.
Though some of the country's 10 million-plus diesel engines - the "legacy fleet" - will be retired over time to reduce pollution, many will stay in use for the next 20 years, the EPA says.
The program strongly prioritizes fleets in disproportionately polluted areas, like those near ports and rail yards, according to the EPA's statement.
Researchers note that the /Niagara Frontier Transportation Authority, for instance, received a grant to retrofit 19 transit buses operating in Buffalo and Niagara Falls, N.Y.
The transit authority's executive director, Kimberley Minke, said it "takes pride in offering environmentally safe and efficient transit services for our entire region."
Grant recipients can be found here .
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