Development and Demonstration of Techniques for Reducing Occupational Radiation Doses During Refueling Outages. Task 1. Steam Generator Channel Head Decontamination

摘要

The overall objective of Task 1 was to demonstrate an effective method for removing tenacious corrosion products in a pressurized water reactor steam generator and thus significantly reduce radiation exposure during subsequent maintenance activities. Various decontamination methods were evaluated and a multistep, low concentration chemical process originated by Kraftwerk Union A.G. (KWU) of the Federal Republic of Germany was selected. The process was further developed and tested by C-E and KWU in West Germany and at C-E's facilities in Windsor, Connecticut. C-E designed, fabricated and tested a portable system to apply the process at Millstone Point II. The decontamination of the primary channel heads of the two Millstone steam generators was performed by C-E and NUSCO during the 1983 refueling shutdown of Millstone Point II plant. Results of the decontamination were very satisfactory. NUSCO determined that a net savings of 3660 man-rem of personnel exposure was realized during the decontamination demonstration and the subsequent maintenance work on the steam generators. (ERA citation 10:016112)