Sewage Plant Byproducts May Hold Radioactive Waste, Report Warns : Environment: Evidence of contamination is found at 14 facilities nationwide, but none in California.

Citing evidence of contamination in 14 municipal sewer systems nationwide over the past decade, the General Accounting Office warned Tuesday of the danger of radioactive waste in the sludge and ash formed at sewage treatment facilities and often recycled into fertilizer and compost.

In a report released to Congress, the GAO does not cite an imminent threat to public health or mention problems in California.

But it raises concerns for people who work with the material and contends that the Nuclear Regulatory Commission, which oversees the handling of radioactive materials, has not been monitoring the amount of radioactivity collecting at sewage treatment plants.

The report says that nearly 25,000 facilities have licenses to use and dispose of radioactive materials, but only 15 have been inspected by the commission.

According to the report, “the full extent of the radioactive contamination of sewage sludge, ash and related byproducts nationwide is unknown. Neither the NRC nor the Environmental Protection Agency has conducted or required testing to determine the extent of the radioactive contamination occurring at treatment plants that receive radioactive discharges.”

The GAO report is based on contamination studies at sewage treatment plants in Portland, Ore.; Washington; Cleveland and Youngstown, Ohio; Ann Arbor, Mich.; Vicksburg, Miss.; Springfield, Mass.; Tonawanda and Grand Island, N.Y.; Oak Ridge and Erwin, Tenn.; Royersford, Pa., and two unidentified Texas cities, said Gene Aloise, the GAO official in charge of the report.

NRC officials acknowledged to a U.S. Senate committee Tuesday that radioactive materials were found in sewage sludge, but that radioactivity amounts “were below levels that would cause concern for public health and safety.” Still, they said, enough contamination existed to require cleanups in some cases.

Legally discharged by hospitals, laboratories and a variety of manufacturing companies, limited quantities of radioactive waste matter regularly are flushed into the nation’s sewer systems where dilution is supposed to render the material harmless.

However, the report cites several cases in which, instead of dispersing, the radioactive materials re-concentrated in the sludge and ash that is filtered out of the waste water passing through treatment plants.

In at least five cases, the report says, the amount of radioactivity could expose people to 100 millirems--the maximum dose permitted by the NRC.

“A threat to public health and safety may not always exist if the NRC’s criterion is exceeded,” the report states, “but according to a former NRC commissioner, exceeding the criterion is a public health and safety concern.”

Excessive exposure to radioactivity poses risks of cancer and genetic damage to fetuses. How much exposure is excessive remains under discussion and debate. From natural sources, including minerals in the soil and the sun’s rays, people can be exposed to several hundred millirems of radiation each year.

At a Cleveland sewage treatment plant discussed in the report, radiation levels were 20 times higher than naturally occurring levels.

In California, no program monitors radioactivity in sludge, said Gary Butner, a senior health physicist with the state’s Department of Health Services radiologic health branch.

“But that’s not to say we haven’t looked,” said Butner, adding that his office has conducted occasional inspections of municipal sewage treatment plants. “We’ve never turned up a problem,” he said.

During the congressional testimony Tuesday, NRC Chairman Ivan Selin disputed at least one of the GAO’s contentions and said no additional regulatory action is required--beyond what the NRC already has done to correct the problem.

“All the licensee sites have been inspected on a routine basis over the years,” he said. “Their sewer discharges were found to have been in compliance with NRC regulations applicable at the time.”

In 1991, the NRC concluded that the release of insoluble radioactive waste into sewers was responsible for the re-concentration of the material in sludge and ash. The agency subsequently prohibited disposal of such waste matter into sewers, Selin said.

Although the NRC expects that action to “resolve the identified re-concentration problem,” Selin said the agency has commissioned a further study.

The report faults the NRC’s proposed study because “it would not require any testing at treatment plants but would rely on existing data from prior case studies of contamination at treatment plants.”

The GAO report states that the NRC’s ban on sewer disposal of insoluble radioactive waste “will address much of the problem of concentration but may not solve it entirely because even soluble materials that are allowed to be discharged could still concentrate as the result of chemical changes that could occur during the waste water treatment process.”

The report recommends that the NRC notify all treatment plants that receive radioactive waste that they may be generating contaminated sludge and ash. It also suggests that testing may be necessary and that the NRC establish acceptable limits for radioactivity in all sewage treatment byproducts.