A test of 50 California trash dumps found that 22 contained unusually high levels of radiation, state environmental officials disclosed Wednesday, raising new questions about a state policy that until recently allowed mildly radioactive waste to be disposed of at local landfills.
The dumps where the radioactivity was detected covered a broad spectrum of waste facilities, from the Kettleman Hills toxic waste site in rural Kings County to ordinary municipal landfills in suburban Calabasas and the San Fernando and San Gabriel valleys.
State environmental health officials immediately cautioned that more testing was needed and that some of the radiation may come from natural mineral deposits near the landfills, or from relatively benign sources such as the glow-in-the-dark exit signs commonly seen in movie theaters.
"The best possible news would be that it was not there at all. The good news here is that it is for the most part safely contained," said California Environmental Protection Agency spokesman William Rukeyser.
Nuclear watchdog groups said that it is highly unlikely that naturally occurring sources are responsible for the high radiation levels at so many locales and argued that the culprit was almost certainly man-made radioactive waste from nuclear power plants or research facilities.
"The data suggests there has been vastly more dumping of radioactive waste over the last decades, unbeknownst even to the dump operators, than anyone suspected, and at levels that do raise health concerns," said Daniel Hirsch, president of the Los Angeles anti-nuclear group Committee to Bridge the Gap. "One should not be finding these kinds of levels in municipal landfills."
California officials acknowledged last year that for at least two decades, the state Department of Health Services permitted some mildly radioactive waste to go to city dumps because they considered the material harmless.
The revelation has angered anti-nuclear activists, environmental groups and some members of the state Legislature who disagree that the waste is completely safe and note that municipal landfills were not licensed or designed to safely contain the material.
The disclosure has also upset the landfill companies themselves, who said they were never told the state was allowing radioactive refuse to go to their dumps, and local politicians, who say they were never notified of what some consider a potential health hazard in their community.
Gov. Gray Davis vetoed legislation last year that would have barred all radioactive materials from municipal dumps, siding with utilities that operate power plants, biotechnology companies, nuclear scientists and state health officials who argued that the waste does not pose a public threat. But Davis immediately followed up his veto with an executive order calling for a partial moratorium on the dumping, which is now in effect.
The data released Wednesday by the California Environmental Protection Agency were the result of sampling at 50 local dumps in California, or about 10% of the statewide total, that was ordered by the state water board.
Of the 26 landfills with a lining to prevent waste pollution from leaking into ground-water supplies, measurements at 16 exceeded maximum drinking-water safety standards.
The linings appeared to have contained the radioactive waste at 25 of the 26. But at one, the Newby Island landfill in Fremont, surrounding ground water was found to exceed state radiation standards.
Ground water surrounding six of the 24 landfills without any lining were found to have radioactivity exceeding safe levels. State officials said they had not determined whether there was any potential exposure to radiation for those who reside near the landfills.
Cal-EPA officials conceded that some of the radiation almost certainly came from man-made materials. Many of the dump sites, including the Calabasas and Sunshine Canyon landfills in Los Angeles County, contained high levels of tritium, a substance found in glow-in-the-dark signs but also a byproduct of nuclear energy production.
Hirsch and other supporters of legislation by state Sen. Gloria Romero (D-Los Angeles) to strip the Department of Health Services of its regulatory power over radioactive materials argued Wednesday that the tests bolster their case.
"My own view is this shows the Department of Health Services has completely failed in its duty to protect the public from the risks of radiation," Hirsch said.
Department of Health Services officials in charge of radiation declined a request to discuss the tests Wednesday.