Contaminants From Coal-Burning Byproduct Affecting Aquatic Wildlife

Contacts:

Jane M. Sanders, (706) 869-9703, Beeper: (706) 785-8289, Email: sanders@srel.edu

Marie Fulmer, (803) 725-9724, Beeper: (803) 867-0284, Email: fulmer@srel.edu

FOR RELEASE JULY 11, 1997

Contaminants from coal-burning byproduct affecting aquatic wildlife

AIKEN, S.C. -- Ecologists at the Savannah River Site are finding high levels of heavy metals in animals exposed to coal fly ash left over from burning coal at the federal reservation, and they suspect that the same problems are widespread because gigatons of coal are burned around the world every year.

Drs. Justin Congdon and Chris Rowe, both of the Savannah River Ecology Laboratory, have found elevated levels of arsenic, cadmium, selenium, strontium and mercury in bullfrog tadpoles and the freshwater softshell turtles that feed on them. The animals live in coal fly ash basins, in areas surrounding the basins and in Beaver Dam Creek that flows for a quarter mile and enters the Savannah River, south of Augusta, Ga.

"We have observed effects on many biological systems of tadpoles exposed to the heavy metals," Dr. Rowe said. "That means the animal is suffering system-wide failure. The contaminants alter tadpole mouth morphology and reduce the tadpole's ability to take in food compared to normal tadpoles. At the same time, tadpole metabolic rates are higher, so they need more energy to maintain themselves. In addition, their ability to escape predators is reduced probably because some of the contaminants are found in the muscles."

Dr. Congdon added: "We think the cadmium is causing the tadpoles to have central nervous system problems. In our experiments, tadpoles taken from clean water quickly flee when they are put in a maze with a snapping turtle, but the turtles are able to capture most of the tadpoles taken from the fly ash area."

Some findings from the researchers' four-year study will be published later this year in the journals Copeia and Journal of Herpetology. The researchers reported the oral deformities of tadpoles from the coal fly ash basins last year in the journal Freshwater Biology. The researchers are continuing to collect data on bullfrog reproduction, and they suspect that it will also be affected, they said.

Less than lethal effects to organisms are often difficult to document, Dr. Congdon said, but it is further complicated when contaminants are transported from the aquatic to the terrestrial environments.

"When some animals feed on contaminated prey, heavy metals can be transferred into the terrestrial environment and into the Savannah River," Dr. Congdon said. "For example, a snake eats a tadpole, and it in turn, is eaten by a hawk, and so on. 'How much is being transferred out into the environment and how?' are the questions we're trying to answer."

Turtles and fish from the Savannah River can enter the areas contaminated by coal fly ash and then return to the river with elevated levels of trace elements, the researchers said. For example, softshell turtles, which are consumed by humans, eat contaminated prey such as fish, crayfish and clams found in and near the ash basins, the researchers said. Then they may return to the Savannah River. Once in the river, soft-shelled turtles can transport the trace elements long distances from the source of contamination, Dr. Congdon said.

Fish from the river can swim up the creek and feed on plants and animals that may have been exposed to the same heavy metals from runoff and other pathways, Dr. Congdon said. He and Dr. Rowe have begun sampling for fish from the ash basin to the river, but have not yet analyzed them for contaminants.

Researchers at the Savannah River Ecology Laboratory are also looking at possible contamination to plant seeds to see if any of the pollution is leaving the Savannah River Site boundaries through seed-eating birds and animals. That work, to be done by fellow Ecology Laboratory researcher Dr. Ken McLeod, has not yet begun.

Continued reliance on coal as a major energy source worldwide may pose greater problems than scientists previously believed, Drs. Congdon and Rowe said. Because coal ash pollution is causing substantial problems in aquatic organisms on the Savannah River Site, researchers believe that aquatic organisms are being affected worldwide. Drs. Congdon and Rowe said they believe the environmental effects of coal ash pollution on aquatic organisms represent "a staggering problem and one that people are not going to want to address." Research into the problems related to coal fly ash storage and disposal should become a priority because about 100 million metric tons of fly ash are produced each year in the United States alone, they said.

To reduce the adverse environmental effects of using coal as an energy source, the Department of Energy is pursuing a "clean coal" facility to generate power for the Savannah River Site, DOE officials said. This new facility will eliminate essentially all of the harmful coal fly ash that is normally released into the environment by a conventional coal burning facility. The coal fly ash is instead converted into a useful byproduct called slag, which can be sold. In addition, this "clean coal" facility will dramatically reduce that amount of sulfur dioxide and nitrogen oxide compounds, which are gases that contribute to acid rain and global warming.

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FOR MORE INFORMATION: To conduct interviews, you may contact the researchers directly, or seek assistance from one of the public information officers listed above.

1. Dr. Justin Congdon, Phone: (803) 725-5341 or Email: congdon@srel.edu

2. Dr. Chris Rowe, Phone: (803) 952-9041 or Email: rowe@srel.edu (After Aug. 1, 1997, you may reach Dr. Rowe at the University of Puerto Rico at (787) 764-0000, ext. 3551.)

DOE CONTACT: 1. Rick Ford, U.S. Department of Energy, Savannah River Site. Phone: (803) 725-8449.

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