EPA nuclear dump radiation limit expected this year--  Official

The federal Environmental Protection Agency expects to finalize a radiation safety standard by the end of this year for a planned nuclear waste dump in the Nevada desert, a public health officer said.

Capt. Ray Clark, of the U.S. Public Health Service and team leader for Yucca Mountain project standards, told a conference Monday in Las Vegas that the radiation limit will be designed to protect people living near the repository for 1 million years.

But he declined to say what confidence he would have in such a standard based on climate changes and corrosion of metal waste containers at the planned repository for the nation's most radioactive waste.

Establishing a confidence level will be left to the Nuclear Regulatory Commission, the agency that must review an Energy Department license for the Yucca Mountain project.

Asked if radiation dose calculations would be meaningful beyond 500,000 years, Clark said, "We have qualms about that."

Clark said that was why the EPA first proposed a 10,000-year standard for radiation safety at the site, 90 miles northwest of Las Vegas.

In July 2004, the U.S. Court of Appeals for the District of Columbia Circuit invalidated the 10,000-year standard, ruling it disregarded recommendations of a National Academy of Sciences panel that it cover peak dose periods of up to 1 million years.

In August 2005, to satisfy the court's ruling, the EPA proposed a two-tiered standard with one set of limits set at 15 millirem above natural background radiation for the first 10,000 years of repository operation and a second standard of up to 350 millirem for succeeding years, up to 1 million years.

By comparison, a chest X-ray exposes a patient to 10 millirem while a mammogram results in a 30 millirem exposure.

Nevada officials have criticized the proposed two-tiered standard, saying the EPA has backpedaled from its previous stance that a 150 millirem dose is unacceptable.

Some 400 attendees from 22 countries are attending the annual International High-Level Radioactive Waste Management Conference sponsored by the American Nuclear Society runs through Thursday at the Texas Station hotel-casino in a Las Vegas. The conference theme is "Global progress toward safe disposal."

The Energy Department plans to submit a license application to the Nuclear Regulatory Commission for the Yucca Mountain repository in 2008, or four years later than had been planned, Energy Secretary Samuel Bodman has said.