The Salt River Project, besieged by state and federal regulators over pollution problems at its Navajo Generating Station near Page, is facing yet another public-relations blow. Federal wildlife biologists suspect emissions from the power plant may be causing toxic contamination in the fish of nearby Lake Powell.
Recent samples of striped bass, a popular sport fish, contained almost three times as much selenium near the plant as did fish caught 140 miles upstream, says Bill Kepner, a biologist with the U.S. Fish and Wildlife Service in Phoenix. Previous testing also has found elevated selenium levels in largemouth, black crappie and walleye taken from Wahweap Bay, next to the huge plant.
The selenium problem is unrelated to the $455,998 fine imposed last week on SRP by federal officials for hazardous-waste violations at the Page plant. SRP also faces pressure from state and federal officials to reduce sulfur-dioxide emissions, which are believed to be fouling the air inside Grand Canyon National Park.
By comparison, SRP officials say selenium contamination is a minor issue. They contend that the plant is an unlikely source for most or all of the selenium in nearby fish.
Some of the fish samples recently taken by federal officials were too full of selenium to be eaten under guidelines established in California.
Arizona has not set limits for selenium contamination in food as has California, site of the worst selenium-poisoning disaster yet recorded. (Selenium in agricultural run-off caused the ecological collapse of the Kesterson National Wildlife Refuge in central California, once an important breeding area for many wild birds.)
"Soils upstream are very high in selenium--the river drops its load as it enters the lake--so we expected the values to be highest there," Kepner says. "What we saw was the reverse. Fish contamination was much higher near the dam than where the river enters the lake."
The highest contamination levels in edible portions of the fish near the plant were 1.77 parts per million, almost twice the California standard of one part per million. "Typically, California will issue a health advisory for young children and pregnant women to curtail consumption of fish containing selenium at the level we're seeing near the plant," Kepner says.
Kepner and other federal biologists believe the Page power plant is pumping out selenium, a heavy metal found in coal that fuels the plant, in waste emissions that later settle on the surrounding land and water. They are pushing for a complete study of the issue, saying the findings, which involve a small number of fish samples, demand further investigation.
SRP officials say they might cooperate in such a study, "if we're asked nicely," says spokesman Larry Crittenden, but they don't believe their plant is to blame. "We've calculated that even if you took all the selenium that Navajo emits and injected it directly into the lake, it wouldn't result in a fraction of the concentrations found in the fish."
Crittenden says the agency's calculations, though admittedly rough, are based on a series of analyses last year that found coal feedstock contained two to three parts per million of selenium.
"Our calculations assume 100 percent of that goes out the smokestacks and 100 percent precipitates into the lake and 100 percent dissolves into the water," he says. "Even assuming all that, we figured the selenium concentration in water would be nineteen parts per trillion, compared with a federal drinking-water standard of .01 parts per million, or 10,000 parts per trillion."
Kepner, however, contends that selenium concentrations in water reveal little. "The route of concern is food intake," he explains. "Selenium is a material that concentrates as you move up the food chain. It settles out of the water into sediment and is taken up by plants and animals, increasing at each level of consumption."
Fish taken near the power plant contained about six times the national average for selenium, high enough to cause chronic toxicity, Kepner says. "You won't see a massive die-off at these levels but, based on the research done at Kesterson, we are looking at fish in that range where reproductive impairment occurs," he says.
Despite the notoriety of the Kesterson poisoning, which was caused by irrigation water leaching selenium from the soil of surrounding farmland, coal-fired power plants most frequently have been the culprit in other cases of selenium poisoning in wildlife.
Nationally, there have been four documented episodes where selenium accumulations high enough to poison aquatic life have occurred, says Dennis Lemley, a research biologist with the U.S. Fish and Wildlife Service national contaminants laboratory in Columbia, Missouri. Three of the four were associated with individual coal-fired power plants. The fourth occurred at Kesterson.
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Based on the Lake Powell findings, the Arizona chapter of the Wildlife Society and other environmental groups are expected to seek inclusion of the Page power plant in a major federal environmental investigation being planned for the area.
The investigation has been triggered by concern that power-generating operations at Glen Canyon Dam are damaging the Grand Canyon. "Scoping" hearings, to decide what the study will include, are scheduled for January in Phoenix and elsewhere in the state.
Last week's fine of nearly half a million dollars assessed to SRP by the U.S. Environmental Protection Agency was prompted by chromium contamination of groundwater near the plant and violations of hazardous-waste storage rules. The EPA ordered the utility to figure out new ways of disposing of paints, solvents, oil sludge and cleaners. SRP General Manager A.J. "Jack" Pfister says the utility already had stopped its practice of dumping chromium, used as a rust inhibitor, in an unlined ditch.
The EPA also has blamed the 2,250-megawatt plant, which is fifteen miles upstream from the Grand Canyon, for 40 percent of the winter haze that shrouds the national park. SRP is in the middle of hearings before the Arizona Air Pollution Control Hearing Board on whether it should begin daily monitoring of sulfur-dioxide emissions. SRP officials contend that the plant's emissions aren't a major contributor to the haze and that state officials are overstepping their authority by ordering more tests.