Air pollution is often thought of as just a big-city problem – after all, that’s where the cars and the factories are. But diesel-powered farm equipment contributes to air pollution too, as do the trucks, trains and ships that move vast amounts of agricultural goods from farm to market throughout the nation every day.
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A no-till system helps reduce harmful diesel emissions on a Midwest farm. Fewer passes through the field means less smog and soot in the air.
Photo courtesy of U.S. EPA |
Reducing diesel emissions is the goal of the Midwest Clean Diesel Initiative (MCDI), a public-private partnership led by U.S. Environmental Protection Agency Region 5, headquartered in Chicago. MCDI promotes the idea that there’s a lot that private business can do – including the agriculture industry – to cut the amount of diesel exhaust polluting our air.
For example, Region 5 air quality experts point out that improved air quality is one advantage of Crop Residue Management. Until recently, measuring that benefit was a little tricky, but Region 5 agriculture specialists Jon Nicholas and Steve Rosenthal have found a way to help farmers visualize the impact they can have on air quality.
“Farmers who use conservation tillage can help clear the air while saving money and time,” Nichols says. “EPA studies show that by switching to a no-till system, a corn farmer on an average-size American farm – about 441 acres – would reduce nitrogen oxide emissions by 1,122 pounds a year. That’s the same as taking 29 cars off the road for an entire year. It makes the air easier to breathe.”
Nichols says the greatest environmental effect comes with no-till, but other forms of conservation tillage can also help reduce emissions. Using a reduced-till system could produce emission reductions equal to taking 15 cars off the road for a year.
Cleaner Water, Too
“It’s not just nitrogen oxide, either,” says Nichols. “There are corresponding reductions in other harmful pollutants, including hydrocarbons, carbon monoxide and particulate matter.”
In addition, environmental scientists believe that soil is better able to retain pollutants and other earth-warming gases when the field is not plowed and residue is maintained. A collateral benefit is a reduction in nonpoint source water pollution, which has become the nation’s leading water quality problem, especially in agricultural communities.
“No-till also promotes a reduction in erosion and nutrient-rich topsoil loss,” Rosenthal says. “That improves water quality because it helps reduce fertilizer run-off that can pollute lakes, rivers, streams – some of which may be sources of drinking water.”
Diesel Engines = Smog and Soot
The biggest contributor to air pollution on most farms is the diesel
engine. Diesels power the majority of tractors, combines and other farm
equipment in America, as well as most commercial trucks, trains and ships.
But diesel-powered engines give off emissions that contribute to
ground-level ozone, also known as smog, and particulate matter, commonly
called soot. Two EPA health assessments on the effects of diesel exhaust,
published in 2000 and 2002, show these harmful emissions have been linked to
an increase in hospital admissions for coronary and respiratory illness.
Through these and other studies, EPA has concluded that diesel exhaust is
"likely to be carcinogenic to humans at occupational and environmental
(ambient) levels of exposure." (Details can be found at
http://cfpub.epa.gov/ncea) EPA’s Health Assessment Document for Diesel
Engine Exhaust provides a full discussion of the data and the uncertainties
in those data that led to this conclusion. (US EPA, Health Assessment
Document for Diesel Engine Exhaust (May 2002)).
As Nichols and Rosenthal point out, EPA’s most recent
National Emissions Inventory shows so-called “mobile emission
sources” are a leading contributor to air pollution in this
country. That means tailpipes – including those on non-road
equipment found on farms and at construction sites – are as big
a problem as smokestacks.
MCDI is one way the government is working in partnership with the private sector to bring about reductions in diesel emissions. Agriculture is one of MCDI’s target industries. The others are ports and railroads.
“We work closely with partner organizations to bring about operational changes, technological improvements, the use of clean fuels, and the reduction of unnecessary idling,” Rosenthal says. “Our partners include state, local and tribal environmental agencies as well as companies that see the benefits of reducing diesel emissions. Since that usually means reducing consumption as well, our partners also see an economic incentive – they spend less on diesel fuel.”
Partnership Targets Trucks
One important facet of MCDI is the SmartWay Transport Partnership, an initiative between EPA and the freight industry aimed at reducing fuel consumption as well as greenhouse gases and other air emissions. The partnership was developed jointly by EPA and several carriers and shippers, including Schneider, Swift, Yellow/Roadway, UPS, FedEx, The Home Depot and IKEA. Membership has steadily increased, adding carriers and shippers such as Coca-Cola, Wal-Mart, Walgreens, and the Archer Daniels Midland Trucking Company.
SmartWay can help shippers, carriers, and logistics providers improve their economic performance through reduced fuel consumption, which is becoming increasingly important as diesel prices continue to be high. SmartWay can also help companies improve their public image through recognition by EPA as a steward of the environment, and companies can earn the right to display the SmartWay logo.
The idea is to promote the implementation of strategies and technologies that reduce emissions, including auxiliary power units, bunker heaters, anti-idling ordinances, single-wide tires, increased trailer aerodynamics and the use of alternative fuels such as bio-diesel or ethanol. Through efficiency improvements, the program also reduces our nation’s dependence on foreign oil, which improves our energy security.
Nichols and Rosenthal are quick to point out that while long-haul trucks are the primary target, even trucks hauling grain from the farm to the silo can take advantage of retrofit technologies that reduce diesel emissions.
Contact
For more information on reducing air pollution by cutting diesel emissions, contact Jon Nichols (312) 353-7942, nichols.jonathan@epa.gov, or Steve Rosenthal (312) 886-6052, rosenthal.steven@epa.gov, or visit www.epa.gov/midwestcleandiesel. Other Web sites of interest include www.epa.gov/smartway and www.epa.gov/cleandiesel.
