Harmful diesel emissions from maritime sources at the ports of Seattle, Tacoma and Vancouver, British Columbia, have fallen 5 to 40 percent over the past six years, depending upon the source, according to the 2011 Puget Sound Maritime Air Emissions Inventory released Tuesday.
The inventory compared maritime-related emissions of nitrogen oxides, volatile organic compounds, sulfur oxides, particulate matter, fine particulate matter, diesel particulate matter and carbon dioxide in 2011 to 2005 baseline emissions.
The pollution-reduction efforts were led by the Puget Sound Air Forum, a voluntary organization representing the ports, private-sector companies and public health organizations.
Sources of maritime pollution studied were oceangoing vessels, harborcraft, locomotives, cargo-handling equipment, trucks and fleet vehicles used at the terminals.
The largest category of pollution reduction was volatile organic compounds, which were reduced 40 percent, according to the report. NOx emissions fell 14 percent, SOx emissions 14 percent, PM10 16 percent, PM2.5 16 percent, diesel PM 16 percent and carbon dioxide 5 percent.
Reducing diesel pollution is the goal of the forum members because diesel emissions have been linked to cancer, chronic respiratory and cardiovascular diseases and other health effects.
The biggest drop in diesel particulate matter was recorded for heavy-duty trucks, with a 52 percent drop in emissions. Diesel particulate emissions from oceangoing vessels declined 16 percent, harbor vessels 7 percent, locomotives 24 percent, cargo-handling equipment 40 percent and fleet vehicles 47 percent.
The ports and their transportation partners took a variety of steps to reduce pollution, including a truck-scrapping program, efforts to reduce engine idle time, fleet-modernization programs, implementation of container tracking systems, electric plug-ins for refrigerated containers and the use of cleaner fuels for vessels at berth.
The partnership will use the 2011 inventory results to guide and focus future emissions reduction efforts in the region.
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