Nuclear D&D-Batelle Research Park
Category: Nuclear Decommissioning
Method(s) Used: Wire Sawing
Location: West Jefferson, OH
Wire saws are ideal for removing large sections of heavily reinforced concrete in pulp and paper mills, steel mills, bridges, dams, power plants and for cutting concrete in any area where space is restricted. Battelle and the U.S. Department of Energy used the wire saw for decontamination and decommissioning of radioactive concrete due to its capability to perform cutting with low noise levels, no vibration, and no dust.
Battelle Saves $270,000 Using Wire Saw for Radiological Decontamination & Decommissioning
Project Documentation
The Problem
The JN-3 reactor was built in 1955 and operations were shut down in 1974. In 1975 the reactor was decommissioned to a restricted level using the regulatory limits required at the time. The original decommissioning project included the removal of the fuel and water used in the reactor operation. This decommissioning brought the building to near-free release levels. Twenty-five years later, the instrumentation to detect residual radiation has improved dramatically, allowing lower regulations than the release levels required.
The Solution
The IPM team had to wire saw the concrete wall into 5-10-ton blocks that could be lifted out by the overhead 10-ton crane. The target weight for each block was 17,000 pounds and 64 blocks were removed before the project was completed. The bio-shield consisted of two types of concrete. The standard concrete was 170 pounds per cubic foot and those blocks averaged 8 tons. The Barytes concrete had a higher density of 220 pounds per cubic foot and those blocks averaged 9 tons. Four diamond wire technicians used two wire saws and two hundred feet of 11-mm and 15-mm diamond wire to cut a total of 12,000 cubic feet before the project was completed.
The Result
This type of work has paved the way for future projects of this caliber. A critical mission of the DOE is the restoration of public and private facilities and sites contaminated during the course of work for the federal government. The successful use of the wire saw on this project could result in other radiological decontamination, decommissioning, and restoration projects under the DOE.