Read about the nuclear plant decommissioning project

Understand the background of the Humboldt Bay Power Plant (HBPP), and learn about the project to decommission the nuclear power plant at the facility.

intermediate stage of Unit 1 and 2 decommissioning


The PG&E Humboldt Bay Power Plant (HBPP) is located just south of Eureka near the mouth of Humboldt Bay in Humboldt County, California.

Get a brief history of the HBPP

Before construction of the units at the HBPP site, power to the Eureka area was supplied by a small steam plant fueled by lumber mill and logging waste. Power was supplemented by the steam electric plant of the SS Donbass III, a World War II Russian Lend-Lease tanker that had broken in half. The stern of the tanker was tugged to Eureka, beached, cleaned and wired into the Eureka electric system. The General Electric Company turbine-generator was in excellent shape. In January 1947, the SS Donbass III powerhouse went on line. The HBPP was conceived in the early 1950s because the area demand for power was growing. Unit 1 (commissioned in 1956) and Unit 2 (commissioned in 1958) provided power to Humboldt County for 54 years and 52 years, respectively. The nuclear power plant, Unit 3, was commissioned in August 1963. Unit 3 operated as a 65 megawatt (MW), natural-circulation boiling-water reactor (BWR) with Atomic Energy Commission License #7. Unit 3 was shut down in 1976 for refueling and seismic upgrades. Repairs subsequently extended the planned shutdown period. In that interval, significant changes were made to nuclear safety standards for reactor operation and design. Ultimately, the decision was made that further modifications were not economical, and Unit 3 would not be restarted. In 1983, we announced our intention to decommission Unit 3. In 1986, we requested a Nuclear Regulatory Commission (NRC) license amendment for SAFSTOR, a condition that would permit Unit 3 to store nuclear fuel, but not to operate. We received the SAFSTOR license in 1988.

The PG&E Executive Project Committee approved the HBPP Nuclear Decommissioning Project on October 6, 2009. The decommissioning of Unit 3 was originally scheduled for completion by December 31, 2015. Work at HBPP involves a number of projects, some of which are completed and some continuing.

Learn about decommissioning the nuclear plant

The project to decommission and remove Unit 3 is being done by a group of PG&E-managed contractors. The project will span a period of several years. The decommissioning began by removing radioactive Unit 3 components, piping and some structures. Subsequently, remaining structures and materials will be decontaminated or removed to permit building demolition. At the conclusion of the demolition, site restoration will be performed. At the end of the project, the structures remaining on the site will be:

  • The Independent Spent Fuel Storage Installation (ISFSI).
  • The Humboldt Bay Generating Station (HBGS).
  • The switchyard.
  • Limited office space.

a mural, commissioned August 2010

This photo shows a mural, commissioned August 2010, commemorating the legacy of the plant, on the outside of an office building that will remain.

As of April 2012, the following progress was completed on the project:

  • Completed construction of the ISFSI. Spent nuclear fuel was transferred from the Unit 3 Spent Fuel Pool to the ISFSI in 2008.
  • Completed construction of the HBGS in 2010, permitting decommissioning of Units 1 and 2.
  • Completed above-grade demolition of Units 1 and 2 in 2011, providing space for the final stages of Unit 3 decommissioning and demolition.
  • Successfully removed large Unit 3 components (transformers, turbine, generator and condenser) and safely transported these oversized, overweight shipments to their disposal sites.
  • Began reactor vessel segmentation and removal, with completion scheduled for year-end 2012.

Learn about the HBGS

The HBGS began commercial operation on September 28, 2010, with technology that provides cleaner and more reliable electricity to Humboldt County. The generating station consists of 10 reciprocating engines (model 18V50DF, manufactured by Wärtsilä). With 163 MW total output, the HBGS provides power to approximately 120,000 homes. The HBGS is 33 percent more efficient than the old HBPP fossil fuel Units 1 and 2, with 83 percent fewer ozone precursors and 33 percent fewer carbon dioxide (CO2) emissions. The generating station employs a closed-loop cooling system with negligible water usage, eliminating the use of water from Humboldt Bay for once-through cooling. The Wärtsilä reciprocating engine technology is ideal for providing a reliable backup to intermittent renewable resources, such as wind power resources, which are currently being developed in the region. The HBGS normally runs on natural gas, with ultra-low sulfur diesel as its backup fuel.

HBGS engine building


The HBGS engine building.

Learn about the HBPP fossil unit

Four fossil-fueled units were located at the HBPP:

  • Two steam boiler plants (52 MW and 53 MW for Units 1 and 2, respectively)
  • Two trailer-mounted Mobile Emergency Power Plants (MEPPs), which were placed at the plant in 1976 to produce additional power after the shutdown of Unit 3

Each MEPP used a jet engine and gas turbine to drive an electric generator to produce electricity. The steam boilers were primarily fueled by natural gas (with an option of fuel oil as a backup), and the two combustion turbines used diesel oil for fuel.

Unit 1 was retired on September 30, 2010, after 54 years of service. Unit 2 was retired on September 27, 2010, after 52 years of service. The existing HBPP Units 1 and 2 and the two combustion turbine units were replaced by the 10 new units of the HBGS.

ntermediate stage of Unit 1 and 2 decommissioning


This photo shows the intermediate stage of Unit 1 and 2 decommissioning, with the structure wrapped in a white membrane for safe asbestos abatement.

View related information

Following are the members of the Humboldt Bay Power Plant – Unit 3 Nuclear Decommissioning Team:

  • Loren Sharp, Director and Nuclear Plant Manager
  • John Albers, Rad Protection Manager
  • Robert Arroyo, Site Services Manager
  • Andrew Cordone, Project Superintendent
  • Kerry Rod, Decommissioning Manager
  • Mark Smith, Engineering Manager

The HBPP Community Advisory Board (CAB) meets regularly to provide a public perspective on plant activities. We thank the following people for their participation:

  • Rex Bohn, 1st District Supervisor, Humboldt County Board of Supervisors
  • John Driscoll, Field Representative, The Office of U.S. Representative Jared Huffman
  • Mariann Hassler, Carpenters Local 751
  • Jennifer Kalt, Director, Humboldt Baykeeper
  • Michael Manetas, HSU Environmental Resources Engineering Dept., Retired
  • Matthew Marshall, Executive Director, Redwood Coast Energy Authority
  • Dave Meserve, Former Arcata City Council Member
  • Holly Nash, Humboldt Hill Resident
  • Ross Nash, Board Member, South Bay Union School District
  • Julie Owens, King Salmon Resident
  • Jimmy Smith, Former 1st District Supervisor, Humboldt County Board of Supervisors
  • Dr. Angus Stewart, King Salmon Resident
  • Donna Stoneman, Former Humboldt Hill Resident
  • Gary Storts, Superintendent/Principal, South Bay Unified School District
  • Don Tuttle, Humboldt County Dept. of Public Works, Retired
  • Michael Welch, Redwood Alliance