PPG to Lower Mercury Emissions at Natrium Plant
The state of Maryland has entered into a settlement agreement with PPG Industries, Inc. (PPG) to reduce toxic mercury emissions at its Natrium, W.V., facility, according to Attorney General Douglas F. Gansler.
PPG also has stated as part of the agreement that it supports the goal of replacing its existing mercury-based production process at the Natrium facility with mercury-free technology.
For decades, mercury released by the Pittsburgh-based company's plant in West Virginia has polluted Maryland's air and water as a result of its production of chlorine and other chlor-alkali chemicals. The agreement announced on Aug. 10 requires the company to reduce mercury emissions to no more than 150 pounds per year by 2011 and no more than 145 pounds per year by 2013 —- an 87.5 percent reduction from 2004 emission levels. Existing regulations set no limit for mercury emissions by chlor-alkali plants. If PPG exceeds the emissions limits set forth in the agreement, the company will face penalties of up to $240,000 per year.
"As we develop new strategies and increase enforcement efforts to clean up Maryland's air and water, we must look at pollution sources emanating outside the state," said Gansler.
PPG's Natrium facility sits on the Ohio River, approximately 72 miles west of the West Virginia/Maryland border. A portion of the Natrium facility, which was built in 1957, uses an outdated, mercury-based production process that remains in use at only four of the 119 chlorine plants in the United States. The mercury-based process is being eliminated in many countries and the U.S. Environmental Protection Agency has banned construction of new plants that use the process.
In addition to discharging mercury into the Ohio River at the plant, the Natrium facility emits airborne mercury that is carried by prevailing winds into Maryland and is deposited onto the land and into the waters of Maryland, particularly in western Maryland. In 2005, EPA reported that although the Natrium facility was the second smallest chlor-alkali plant in the United States in terms of production, it was the second largest in terms of mercury air emissions. From October 2005 to March 2006, EPA identified the Natrium facility as a "high priority violator" under the Clean Air Act. PPG has taken steps to reduce mercury emissions from the plant, and its agreement with Maryland requires PPG to continue environmental improvements while the mercury-based process remains in use.
Mercury is a hazardous neurotoxin that accumulates in the environment and particularly in aquatic wildlife. According to EPA data on mercury deposition, Maryland ranks among the states most severely affected by concentrated mercury. As a result of mercury deposition in Maryland, waters throughout Maryland are designated as impaired because of mercury concentrations in fish tissue. The problem is particularly acute in western Maryland, where virtually every freshwater lake or impoundment is impaired. Mercury concentrations in fish tissue in Deep Creek Lake, Savage River Reservoir, and Big Piney Reservoir average almost double safe concentrations.