Navigation Links
Duke scientists look deeper for coal ash hazards
Date:11/29/2010

DURHAM, N.C. As the U.S. Environmental Protection Agency weighs whether to define coal ash as hazardous waste, a Duke University study identifies new monitoring protocols and insights that can help investigators more accurately measure and predict the ecological impacts of coal ash contaminants.

"The take-away lesson is we need to change how and where we look for coal ash contaminants," says Avner Vengosh, professor of geochemistry and water quality at Duke's Nicholas School of the Environment. "Risks to water quality and aquatic life don't end with surface water contamination, but much of our current monitoring does."

The study, published online this week in the peer-reviewed journal Environmental Science and Technology, documents contaminant levels in aquatic ecosystems over an 18-month period following a massive coal sludge spill in 2008 at a Tennessee Valley Authority power plant in Kingston, Tenn.

By analyzing more than 220 water samples collected over the 18-month period, the Duke team found that high concentrations of arsenic from the TVA coal ash remained in pore water -- water trapped within river-bottom sediment -- long after contaminant levels in surface waters dropped back below safe thresholds. Samples extracted from 10 centimeters to half a meter below the surface of sediment in downstream rivers contained arsenic levels of up to 2,000 parts per billion well above the EPA's thresholds of 10 parts per billion for safe drinking water, and 150 parts per billion for protection of aquatic life.

"It's like cleaning your house," Vengosh says of the finding. "Everything may look clean, but if you look under the rugs, that's where you find the dirt."

The potential impacts of pore water contamination extend far beyond the river bottom, he explains, because "this is where the biological food chain begins, so any bioaccumulation of toxins will start here."

The research team, which included two graduate students from Duke's Nicholas School of the Environment and Pratt School of Engineering, also found that acidity and the loss or gain of oxygen in water play key roles in controlling how arsenic, selenium and other coal ash contaminants leach into the environment. Knowing this will help scientists better predict the fate and migration of contaminants derived from coal ash residues, particularly those stored in holding ponds and landfills, as well as any potential leakage into lakes, rivers and other aquatic systems.

The study comes as the EPA is considering whether to define ash from coal-burning power plants as hazardous waste. The deadline for public comment to the EPA was Nov. 19; a final ruling -- what Vengosh calls "a defining moment" -- is expected in coming months.

"At more than 3.7 million cubic meters, the scope of the TVA spill is unprecedented, but similar processes are taking place in holding ponds, landfills and other coal ash storage facilities across the nation," he says. "As long as coal ash isn't regulated as hazardous waste, there is no way to prevent discharges of contaminants from these facilities and protect the environment."


'/>"/>

Contact: Tim Lucas
tdlucas@duke.edu
919-613-8084
Duke University
Source:Eurekalert

Related biology news :

1. Jefferson scientists deliver toxic genes to effectively kill pancreatic cancer cells
2. Scientists identify novel inhibitor of human microRNA
3. Argonne scientists peer into heart of compound that may detect chemical, biological weapons
4. MU scientists go green with gold, distribute environmentally friendly nanoparticles
5. Scientists identify gene that may contribute to improved rice yield
6. Scientists discover why a mothers high-fat diet contributes to obesity in her children
7. MU scientists see how HIV matures into an infection
8. Earth scientists keep an eye on Texas
9. Thinking it through: Scientists call for policy to guide biofuels industry toward sustainability
10. Scientists identify a molecule that coordinates the movement of cells
11. Scientists Find new migratory patterns for Mediterranean and Western Atlantic bluefin tuna
Post Your Comments:
*Name:
*Comment:
*Email:
(Date:3/31/2016)... -- Genomics firm Nabsys has completed a financial  restructuring under ... M.D., who returned to the company in October 2015. ... including Chief Technology Officer, John Oliver , Ph.D., ... Vice President of Software and Informatics, Michael Kaiser ... Bready served as CEO of Nabsys from 2005-2014 and ...
(Date:3/21/2016)... 22, 2016 Unique technology ... for superior security   Xura, ... of secure digital communications services, today announced it is ... offer enterprise customers, particularly those in the Financial Services ... voice authentication within a mobile app, alongside, and in ...
(Date:3/14/2016)... NXTD ) ("NXT-ID" or the "Company"), a company ... of a new series of commercials on Time Warner Cable ... .  The commercials will air on Bloomberg TV, Fox Business ... show. --> NXTD ) ("NXT-ID" or the "Company"), ... the airing of a new series of commercials on Time ...
Breaking Biology News(10 mins):
(Date:5/3/2016)... ... 03, 2016 , ... Leading CEOs from biotech, pharmaceutical, and ... June 1st at The Four Seasons Hotel Boston. , The Boston CEO Conference ... exclusive access to key decision makers who influence deal making and investment. Attendees ...
(Date:5/3/2016)... ... 03, 2016 , ... Kerafast Inc., developers of an ... the globe, today announced the availability of a Zika virus antibody from Vanderbilt ... and prevention measures for the Zika virus, the virus’s geographical distribution continues to ...
(Date:5/3/2016)... -- - And Other Rising Companies - ... Competitor Biologics  - Biosimilar Drug Producers - ... Who are the most important and promising ... sales potentials? Discover, in our updated survey, organisations, outlooks ... revenue forecasting. Visiongain,s new study ...
(Date:5/3/2016)... , ... May 03, 2016 , ... According to world ... for definitive prostate cancer treatment, patients traditionally had two main treatment options: surgery or ... would be made. , New technology has enabled doctors to administer higher doses ...
Breaking Biology Technology: