Agenda - 11-17-1998 - 5a - Laserfiche WebLink

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r' ~ .L~ '1t ..~; .-G' . ~•.. a r~~ w' ~ t• ~,q~ '~ _ + r L..•~ -".. 'L'am. - ~y .v : , i -_ - ~74L ~ Chapter E;oht • Spent Fuei Rlsks +; pathway. The HP technicians standing at the spent fuel pool railing holding the Y teietectors at waist height pointed at spent fuel assemblies essentially had "guns" aimed at vital organs. In June 1952, a diver installing storage nck support plates in the Indian Point Unit 2 spent fuel pool received an exposure of about 3.7 Rem to his head. A w second diver received a ~•hole body dose of about 1.6 Rem. An irradiated fuel ' assembly had been inadvertently transferred to a storage location tt+•o to four feet from the divers' r+•ork area. Limited visibilit<~ in the pool caused by cloudy ~•ater and insufficient unden+•ater lighting prevented the misplaced fuel assembly fruin being detected. Alarming dosimeters mounted inside the divers' helmets failed to alarm at the 200 mr setpoint.'" While these events involved tangible hazards to individuals' ++•ell-being, the general public's health and safety +vas ne+•er at risk. Therefore, the risk of radia- tion overexposure +n•hen the spent fuel pool level is maintained is confined to nuclear po~~er plant workers. Handling Mishaps The operation of o+•er 100 nuclear pu+ver plants in this country since Shippingport's startup in December 1957 has requh2d several hundred thousand irradiated fuel assembly movements. Spent fuel assemblies are discharged from the reactor core and irradiated fuel assemblies are repositioned ++•ithin the reactor core every refueling outage. The entire reactor core is periodically off-loaded one assembly at a time to the spent fuel pool to allow in-vessel work, ++•ith fuel assem- blies later reloaded for the next operating cycle. Spent fuel assemblies are mu+•ed within the spent fuel pool for inspections and to allo+v storage rack replacements. Eq~ailures and personnel errors durine these activities have resulted in a few hundre minor incidents such as the following events and similar events summarized in Appendix A. During a refueling outage at Pilgrim in December 1979, an irradiated fuel assembly was inadvertently lifted from the storage racks high enough to acti+•ate the area radiation alarms on the refueling floor. The reactor building overhead crane +vas transferring ne+v fuel assemblies from the inspection stand to the stor- age racks in the spent fuel pout. After a ne+v fuel assembly +,•as placed into a st~r- age rack, the lifting hook caught between the lifting bail and the fuel channel un an adjacent irradiated fuel assembly. The operating staff failed to realize that the irradiated fuel assembly +vas being lifted from the spent fuel pool until the radi- ation alarms sounded. The operators quickly returned the irradiated fuel assem- bly to its storage location. A top nozzle separated from a spent fuel assembly during transfer to tl~e new• high-density fuel storage racks at Prairie Island in December lySl. Tl~i~ foul assembly had operated in the reactor for three cycles prior to being discharged in August 19:8. It failed at a mechanical ball joint behveen stemless steel and zircalov. The failure im•ol+•ed lh joints in the area of maximum ~uryature an~i ~+•~~ 18