EPA tightens Yucca nuke emissions

Thursday, Aug. 19, 1999 | 11:24 a.m.

The federal Environmental Protection Agency issued strict new limits today on the amount of radiation that can escape a proposed high-level nuclear waste repository at Yucca Mountain.

The EPA proposes to limit exposure to 15 millirems a year, adding another standard for the proposed Yucca Mountain repository.

The EPA proposed rule is based on a calculation called a "committed effective dose equation." The equation calculates that the 15 millirems a year would create a probability of seven cancer deaths a year in a population of 1 million people.

Nuclear industry representatives were upset by the EPA's stricter proposal and said the industry would have a difficult time meeting the standards.

Southern Nevadans receive about 330 millirems a year from all sources of radiation -- most of them natural, such as sun rays and rock. The EPA limits would be in addition to that.

The EPA will schedule public hearings around the country on its proposed radiation limit.

In addition, the EPA is limiting the amount of radiation that can escape through ground water over 10,000 years.

The radiation is measured outside the boundary of the Yucca Mountain project, about 12 miles from the actual repository site.

The time frame of 10,000 years was arbitrarily set by scientists who have been working on the Yucca Mountain project, 90 miles northwest of Las Vegas, for the past 20 years.

In contrast, the Nuclear Regulatory Commission, the agency that would issue a license to build and operate a high-level nuclear waste dump has proposed a limit of 25 millirems of radiation and no limit on radiation in ground water. The EPA, however, is responsible to set radiation standards, and the nuclear commission has said in the past that it would abide by whatever standard the EPA sets.

The Department of Energy is responsible for monitoring radiation moving through and outside Yucca Mountain. The EPA is concerned about keeping radiation out of water and air, the most likely pathways for exposure to people.

It would take 310,000 years for an enough radiation to create a 25 millirem dose to escape, the NRC scientists estimate. A peak dose of 85 millirems a year would be reached in 620,000 years after a dump opens, the scientists predict.

The NRC is still working on its final rule for Yucca Mountain radiation exposure, commission spokeswoman Sue Gagner said.

Nuclear industry representatives had not seen the rule this morning but said they are unhappy with a stricter exposure rule, which was expected.

In a July 20 letter to the Office of Management and Budget, Nuclear Energy Institute President Robert W. Bishop said that if the EPA proposed a stricter exposure standard than the NRC and a separate ground water rule, the repository project would be threatened because it would cost too much money to build it to meet the limit.

The industry group did not specify how much more a better, more restrictive repository might cost. The institute is the lobbying arm of the nuclear industry.

Bishop urged the Office of Management and Budget to set a radiation limit based on an overall computer model that spells out how a repository at Yucca Mountain would work.

This same recommendation was made by the Department of Energy and the Nuclear Regulatory Commission. In other words, the repository would either pass or fail the one test, rather than be disqualified for ground water moving too fast or nuclear waste containers cracking and releasing their contents too soon.

Both the DOE and the NRC based their findings on a 1995 National Academy of Sciences report that recommended no separate ground water limit on radiation at Yucca Mountain.