Reactor Decommissioning History
San Onofre Unit 1 (SONGS-1)
revised 18-APR-2014

Overview

SONGS-1 was a commercial Westinghouse 3-loop PWR power reactor constructed by Bechtel. It had a generating capacity of 450 MWe and 1347 MWt. It operated from January 1968 to November 1992. It was decommissioned while Units 2 and 3 were operating. Decommissioning of the reactor began 1999. Reactor is removed, but not disposed of.

With the 2013 closure of Songs-2 & -3 there have been thoughts as to if Unit-1 vessel will be segmented or shipped off site whole. Popular scenarios at this time are shipping all 3 RV's whole and segmenting all 3. Segmentation of Songs-1 would be challenging in that the Reactor Vessel Internals are packed and grouted inside the vessel.

Click here for SONGS-2 & -3 page.

Reactor Decommissioning Specifics

Internals Removal
All work was performed underwater. Abrasive Water Jet (AWJ) and Metal Disintegration Machining (MDM) were primarily used. Some long handle tools were also used for mechanical work such as unbolting and manipulating. The AWJ was used to remove larger components (such as the Baffle Plates) and to size reduce them for packaging. Several MDM tools were used to help remove components (such as removing bolt heads). All work on the internals was done remotely. All work on the internals was done by PCI Energy Services.

Reactor Vessel Removal
The reactor pressure vessel was removed whole with a cover where the head had been. This assembly was to be shipped off-site inside a custom made canister. It is currently "staged" and not disposed of. Possibility of segmenting it or storing on site whole are being considered. The reactor head was shipped separately. It is not published as to which company cut the piping to free the Reactor Vessel. Bigge Power Constructors provided the rigging services to move the Vessel. Diamond wire cutting used on the nozzles (average 22-hours each nozzle with CO2 coolant).

With the retirement of Units-2 and 3 in 2013, plans for segmentation or removal of the Vessel should be known soon.

Segmentation and Packaging Plan (S&P Plan)
Pre-site: PCI Energy Services; Fred Frank, Jim Jesko, George Knetl, Steve Larson.
At site: PCI Energy Services?

Key People
Jim Jesko was the on-site Project Manager for PCI Energy Services.

Contractors
Bechtel.
Bluegrass.
Bigge Power Constructors.
PCI Energy Services.
WMG.

Comments
This was the third underwater internals segmentation's done in the USA using Abrasive Water Jet as the primary cutting tool. PCI had done Abrasive Water Jet cutting of the "sister" design Connecticut Yankee (Haddam Neck) reactor internals previous to this. The Rancho Seco Reactor Vessel was the fourth application (on RVI/RV) of segmenting with AWJ, but was done dry.

Related Publications and Documents
No published technical papers have been found relating to the decommissioning of this reactor or segmentation of the reactor internals.

References
NRC's "Fact Sheet on Decommissioning Nuclear Power Plants" (web page 8/15/05).
Southern California Edison's web page as of 8/12/05.
Bigge Power Constructors' web page as of 8/12/05.
PCI Energy Services' web page 8/12/05.
Steve Larson interview 8/12/05.
NRC's web page 2/20/10.
Bluegrass web site 2/16/14.

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