Oct 24 - McClatchy-Tribune Regional News - Matt Weiser The Sacramento Bee, Calif.



Sacramento's Rancho Seco nuclear power plant has been formally decommissioned by the federal government, the first action of its kind in response to a public vote.

The 20-year decommissioning process cost Sacramento Municipal Utility District ratepayers $500 million.

District voters decided in June 1989 that such a costly endeavor was justified to eliminate the risks posed by nuclear power.

The vote followed a long series of accidents and costly unplanned shutdowns at Rancho Seco, which began operating in 1975.

"What it represents is the final closure of the Rancho Seco book," said Jim Shetler, SMUD assistant general manager and a former worker at the plant. "The vast majority of the site is no longer under radiological control."

Decommissioning means the Nuclear Regulatory Commission no longer oversees the 80-acre reactor site at the plant, located in rural southeast Sacramento County.

The NRC has verified that residual radioactivity falls below its regulatory standard of 25 millirems per year. The average American absorbs about 300 millirems from background or natural sources. The reactor building, the giant twin cooling towers and other structures won't be torn down because the cost is prohibitive. Much of the site will remain fenced.

Other portions of the reactor property will remain under federal regulation because they hold highly radioactive materials.

No viable disposal options exist for these materials, so they will remain indefinitely.

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Call The Bee's Matt Weiser, (916) 321-1264.

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