RALEIGH, N.C. (AP) — Mercury emissions from coal-fired power plants in North Carolina have gone down 70 percent in the last decade, according to a new study released by the state.
The N.C. Division of Air Quality presented the findings to the state Environmental Management Commission on Thursday.
"We knew that scrubbers and other controls would reduce mercury emissions, but the actual reductions were larger than we expected," DAQ Director Sheila Holman said in a press release.
State officials attribute the decreased presence of the emissions to the 2002 Clean Smokestack Act that forced the state's 14 coal-fired power plants to reduce their nitrogen oxide and sulfur dioxide emissions by about three-fourths over a period of 10 years.
Mercury is a highly toxic metal that can permeate ecosystems and food supplies. High levels of mercury in waters can cause fish to become unhealthy to eat, especially for children and pregnant women.
"This is a reminder that mercury is a huge problem in the state, and when you look across the state and definitely in the coastal planes most waters have mercury problems," said Geoff Gisler, staff attorney with the Southern Environment Law Center.
Power companies responded to the Clean Smokestack Act by installing $2.9 billion worth of scrubbers and other equipment aimed at cutting emissions. From 2002 to 2010 North Carolina coal-fired plant emissions decreased from 3,350 pounds to 960 pounds.
Coal-fired power plants account for a little more than half of the state's mercury air emissions. The rest come mainly from large and small industrial plants. Over the same time period, mercury emissions dropped 54.4 percent in the eight largest industrial sources other than power plants.
Gisler was encouraged by the reductions but said the state still has a long way to go.
"It's very good that we're reducing mercury emissions from coal fired power plants, but we can't forget that 48 percent of the emissions polluting our waters are from other areas," he said.
The study also found that power plants with the highest levels of controls cut their mercury pollution by more than 90 percent.
Airborne emissions account for 98 percent of the mercury found in North Carolina waters, according to the study. Eighty four percent of the mercury emissions come from out-of-state sources and 16 percent comes from the in-state industrial areas and power plants.
Gisler said the report should put to rest some of its opponents fears.
"We're both having the power and producing cleaner air," he said. "The idea that we can have a good economy or cleaner air is simply not true."
Allen Reed can be reached on Twitter at: http://twitter.com/Allen_Reed