Humboldt Bay Nuclear Plant Nears Decommissioning Milestone

December, 2017


As this year draws to an end, another large endeavor also begins to wind down.  In a few months, the decommissioning of PG&E’s Humboldt Bay Nuclear Power Plant just south of Eureka will reach a milestone—all of the radioactive wastes and materials will have been dismantled and excavated, packaged, and shipped off site.  A few more years of environmental cleanup and restoration remain before the project is complete.

The nuclear power plant, one of the first and smallest in the U.S., began operation in 1963, and was shut down for safety and economic reasons in 1975.  The reactor, its spent fuel, and the related radioactive structures were placed in a SAFESTOR condition.SAFESTOR is one of three decommissioning strategies designated by the United States Nuclear Regulatory Commission. Under SAFESTOR, the plant was monitored and secured while a decommissioning plan was designed.  Funds were collected from ratepayers over many years and put into a trust fund to pay for the estimated $1 billion decommissioning cost. 

Beginning in earnest in 2008, the actual dismantlement was a very systematic and time-consuming process.  First, the highly radioactive spent fuel was packaged into five concrete dry casks and placed in a below grade, underground bunker for long-term storage on site.  Then, all the structures, concrete, miles of piping and wiring, metal supports, etc., and the reactor itself, required intricate surveying and analysis of the various levels of radioactive contamination. They then had to be carefully disassembled, packaged, and shipped off site.  More than 6,000 truckloads of wastes were sent to various dumps in Texas, Utah, and Idaho. A sixth onsite cask is filled with internal reactor parts and other very highly radioactive parts from the plant which could not be shipped to other locations due to legal and economic regulations.

A visual presentation tracing the history of this decommissioning, including background information on nuclear power, is available as PowerPoint, PDF, MWV, and a JEPG slide show at this  link:

Photos of a recent tour of  the decommisioned
plant taken by Michael Welch, also a member of the plant’s Community Advisory Board, are available online here:


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