Reactor Decommissioning History
Big Rock Point
revised 2010-02-22

Overview

Big Rock Point was a commercial BWR power reactor. It had a generating capacity of 67 MWe and operated from December 1962 to August 1997. Full power days not known. The reactor was 11-foot 4-inches (3.4-meter) diameter at the vessel flange x 30-foot (9.1-meter) tall. Principally fabricated from steel it weighed 109 Te empty and without the head. Reactor decommissioning, removal and transportation to Barnwell, SC was completed by October 2003.

Reactor Decommissioning Specifics

Internals Removal
Removal of the reactor vessel internals was done by a combination of Big Rock site employees, PCI Energy Services, and MOTA Corporation while the vessel was flooded. MOTA Corporation, who were originally contracted to remove the Major Components, did the size reduction, removal and packaging of the Upper Grid Bars due to the fact the grid bars where GTCC material. MOTA designed and built a first of a kind "Hydraulically Operated Rotary Cutting Equipment" (HORCE). The HORCE enabled the (18) 79-inch (2.0-meter) long grid bars to be cut and removed remotely, loaded underwater into custom built mini cans that were then placed into a Westinghouse W74 fuel storage cask which was then subsequently placed onto the Big Rock ISFSI. Versions of the MOTA HORCE have subsequently been further successfully used at both the Millstone-1 and Rancho Seco internals removal and size reduction projects.

Reactor Vessel Removal
The reactor pressure vessel was removed whole with a custom built bolted top cover plate (TCP) located on the RV flange where the head was bolted during operation. This unique design enabled the top cover plate to be used as the rigging/lifting point for RV removal and then functioned as the closure lid for the RV transportation container. This container was the first ever fully compliant 10CFR Pt 71 shipping container ever licensed in the US. It was designed by S&L out of Chicago and built to exacting physical and material specifications by PCC out of York, PA.

Prior to removal MOTA, using MDM (Metal Disintegration Machining from PCI), Diamond Wire (Cutting Edge), and Clam Shell cutters disconnected and capped all the water, steam and control rod drive pipes/tubes that ranged from 3-inch to 20-inch (76mm to 508mm) diameter to isolate the RV in preparation for removal.

The removal of the RV was overseen by MOTA and supported by Barnhart Crane and Rigging out of Memphis, TN. Once the RV was placed into the shipping container the TCP was welded to the container to form the containment and provide the mechanical robustness necessary to meet demands of the 10CFR Pt 71 Hypothetical Accident Conditions (HAC). The weld had a special 'J' weld profile developed and implemented by PCI and required over 500 kg of filler material to complete taking 6 days of around the clock working.

Once the welding was completed and successfully NDE'ed the internal void of the RV was grouted with low density cellular concrete (LDCC) through injection ports in the TCP. The LDCC was to exacting density and had to be poured in 'lifts' with laboratory analysis conducted between lifts to ensure that the exacting specifications were being met. Once the RV internals were grouted, the ports were welded shut and Barnhart lowered the loaded container onto its side to enable the annulus region between the inside of the container and the RV to be grouted also. Once grouted and the injection ports welded closed the complete package, total weight 266 Te, was carefully slid out of the containment sphere on hydraulic slide rails, lifted and placed onto a 36 axle Goldhofer trailer.

Once all the tie-downs where in place and approvals received at 3:00 am, a briefing was held with the local, state authorities, the NRC and other interested parties and the shipment commenced. Taking (2) days and (2) 1000hp tractor units supplied by Barnhart the package reached a pre prepared rail siding some (52) miles away. With the Mammoet provided rail car, ETMX-1001 waiting, the package was carefully slid from the Goldhofer onto the ETMX-1001. The tie downs were secured, inspections made and then the 1400 mile rail journey commenced.

After (8) days and numerous states the package safely arrived in Barnwell, SC for its final short road trip prior to burial. This was completed safely and without incident in late October 2003. The reactor head was shipped separately to EoU in a custom designed shipping container by Duratek in 2002.

Segmentation and Packaging Plan (S&P Plan)
Pre-site: PCI Energy Services, MOTA Corporation
At site: PCI Energy Services, MOTA Corporation

Key People
Patrick Daly was the on-site Project Manager for BNG America.
Mick Papp was the Project Manager specifically assigned to oversee the RV removal preps and removal and for the design, licensing of the 10CFR Pt 71 shipping container and for the transportation of the loaded container thereafter.

Contractors
BNG America.
PCI Energy Services.
MOTA Corporation (site supervision and labor).
Cutting Edge.
Sargent & Lundy.
Mammoet - Rail Car ETMX-1001.
Barnhart Crane and Rigging, site and off site rigging, road transportation.
Bigge Power Constructors - single failure proof crane.
GTS Duratek - RV Disposal at Barnwell, SC.

Comments
BNG America's first major D&D contract (per bnfl.com as of 8/12/05).

Related Publications and Documents
Nuclear International July 2002
Nuclear Times 2002
Radwaste Solutions Jan/Feb 2004
Mike Papp's "The Final Trip of the Big Rock Point Reactor Vessel", 2003 (PDF)

References
NRC's "Fact Sheet on Decommissioning Nuclear Power Plants" (web page 8/15/05). Consumers Energy's web page as of 8/12/05.
UKAEA web page as of 8/12/05.
MOTA Corporation's web page as of 8/14/05.
BNFL's web page as of 8/12/05.
Patrick Daly correspondence on 8/15 and 8/16/05.
Mick Papp correspondence on 11/2/05.

Click here for the "scheduled" Reactor D&D main page.
Click here for the past and current Reactor D&D main page.