DIRECTOR'S CORNER
Mercury in the environment: How DEQ is responding
As a part of our commitment to protecting the environment and health of Virginia citizens, the Department of Environmental Quality undertakes efforts to monitor mercury, understand the extent of mercury contamination, and reduce its use.
Because mercury affects the environment in many ways, DEQ is addressing the issue on several fronts, including:
- Monitoring Virginia’s waters to identify the extent and location of mercury contamination in fish and sediment.
- Preventing mercury pollution by working with facilities that contribute to mercury in the air and in landfills.
- Developing a comprehensive strategy for reducing mercury in the environment.
- Evaluating emission controls on facilities in support of expected federal regulations.
Mercury is a metal that can affect the environment through natural processes and human activities, which includes manufacturing and other industrial processes. Details of mercury emissions are available in the Virginia Toxics Release Inventory Report.
Eating fish contaminated with mercury is the primary way people are exposed to the pollutant. DEQ and the Virginia Department of Health work together to ensure that elevated mercury levels detected by DEQ result in fish consumption advisories issued by the health department.
As part of DEQ’s fish tissue and sediment monitoring program, we take samples at 80 to 100 sites every year, generally covering the entire state every five years. The fish tissue and sediment samples are tested for a number of pollutants, including mercury.
Until 2002 only three rivers – the North Fork of the Holston River, the South River and the South Fork Shenandoah River – in Virginia had impaired water quality due to mercury, caused by two industrial pollution incidents. Cleanup at both industrial sites is being addressed, and contamination in the South River and the South Fork Shenandoah River is now assessed through a plan for a 100-year monitoring effort.
Normally we focus our efforts on locations with possible nearby contamination sources. In recent years, states from Florida to Maryland and from the Great Lakes to New England have discovered elevated levels of mercury in fish from waters that do not have any direct mercury sources.
These findings prompted DEQ to conduct additional monitoring in waters without significant, known sources of mercury pollution. In 2002 DEQ conducted more extensive fish collections in rivers in the coastal plain, generally the area east of Interstate 95.
We found elevated levels of mercury in some fish in Blackwater River and the Great Dismal Swamp Canal, both in southeastern Virginia, and the Dragon Run Swamp and Piankatank River on the Middle Peninsula. We returned to eastern Virginia the following year to conduct additional tests, searching in smaller lakes, swamps and streams, and again found some sites with elevated mercury levels.
DEQ has identified these waters, along with the rivers in the Shenandoah Valley and southwest Virginia, as having impaired water quality. We added them to a list of waters for which DEQ is working to develop pollution limits, called total maximum daily loads, and cleanup plans.
DEQ staff members collect fish tissue and sediment samples in the Blackwater River to investigate mercury contamination.
The waters that lack obvious contamination sources in eastern Virginia share three characteristics. The waters have:
- Low levels of oxygen.
- High amounts of organic matter.
- Low pH, meaning they are acidic.
These traits are common of swamps, streams and rivers in Virginia’s coastal areas. The pollution sources and the reasons why elevated levels of mercury appear in these waters are not fully understood.
In an effort to gain perspective from public partners, DEQ formed the Mercury Advisory Committee and South River Science Team. Representatives from government agencies, industry and academia participate on the committee and science team.
The South River Science Team has been meeting every two months since 2000 to address the issues about mercury contamination in the South River and South Fork Shenandoah River. The Mercury Advisory Committee met for the first time in April 2004 to consider contamination in eastern Virginia and plans in meet again in early 2005.
DEQ will seek advice from the advisory committee on locations for additional investigations in Virginia’s coastal waters. DEQ also will share results, which are scheduled to be final in early 2005, from the 2004 mercury investigation. Last summer DEQ conducted additional testing for mercury at 24 sites within the Blackwater River, Dragon Run Swamp and Piankatank River, and the Great Dismal Swamp. We hope the additional tests will reveal new information about mercury in Virginia’s waters.
DEQ also has asked the advisory committee, including DEQ representatives from the air and water divisions, to investigate the deposition of mercury emitted from industrial facilities as a suspected cause of contamination in Virginia waters.
One of the best ways to reduce the emission of mercury is to prevent its use in facilities. Mercury enters the steel manufacturing process through switches found in automobiles. If steel dismantlers do not remove the switches, commonly found under the hoods and trunks of cars, the melting of the steel releases mercury into the air. DEQ is supporting a pilot program with a business in Winchester to remove mercury-containing switches from automobiles during its dismantling process, and we encourage all steel dismantlers to adopt a similar program.
DEQ also promotes and coordinates other voluntary efforts across the state to reduce or eliminate the use of mercury. We work with partners to support efforts that reduce mercury in dental offices, schools, office buildings and healthcare facilities. In the past few years, DEQ has partnered with the Virginia Dental Association, the Virginia Department of Health and the U.S. Environmental Protection Agency on series of mercury reduction projects.
One of the most successful programs has been Virginia’s Hospitals for a Healthy Environment, modeled on an EPA initiative. Under this partnership effort, DEQ and healthcare facilities work together to develop plans to manage and dispose of waste and pollutants properly. Program members pledge to eliminate mercury as well as reduce waste and toxic substances. More than 75 healthcare businesses across Virginia have joined.
As we address mercury contamination on several fronts, it is also important to consider how we will meet future challenges. DEQ is evaluating how to approach mercury contamination from a combined air and water perspective and to develop a comprehensive mercury reduction strategy. We are also monitoring the development of federal air regulations related to mercury for guidance on appropriate emission controls.
If our experiences in the Shenandoah and coastal areas are any indication, addressing mercury sources and contamination in the future will most likely be a complicated and time-consuming task. Regardless of the challenges, DEQ will act in the best interest of the environment and the citizens of Virginia.