I. PURPOSE AND SCOPE

The purpose of this project is to upgrade the Unit 2 terminal box, wiring, and conduit on the high pressure coolant injection (HPCI) skid. Currently, the terminal box located in the HPCI room is too small to accommodate all the wiring that it presently contains. Wiring and conduit for the turbine/pump thermocouples, vibration detectors, and HPCI governor end thermocouple wire on the Unit 2 HPCI skid need additional support and/or conduit. The scope of this project is to replace the existing terminal box with a larger one and relocate other relays (i.e., HPCI room door alarm) to this new terminal box. In addition, the project scope also includes rerouting conduit to vibration detectors and thermocouples on the HPCI skid. The conduit is being rerouted to avoid interference with the turbine housing when it is removed for inspection and maintenance. This skid modification will save approximately 400 hours of labor that would be normally required for temporary removal of conduit during turbine inspections. Other minor project work includes replacing non-standard vendor conduit and fittings with standard BSEP equipment and the painting of some skid items. Lessons learned from the Unit 1 (mod 87-181) HPCI skid modification will be incorporated into this project.

Success for the Unit 2 HPCI skid upgrade will be increased reliability resulting in a reduced number of trouble tickets and limiting conditions of operation (LCOs) for this system. Completion of this project will also reduce the time required for routine maintenance and turbine/pump inspection on the HPCI skid.

II. EVALUATION

Schedule Index: 12 - The primary contributor to this schedule index is from the nuclear safety category. A scaling factor of 0.2 was assigned to nuclear safety to account for the moderate impact this project would have on the availability of the HPCI system, which is a system of low importance in preventing and mitigating core damage frequency (0.2 x 32). Upgrading the skid will make a moderate improvement in worker productivity when performing inspections or routine maintenance on the HPCI turbine/pump (0.5 x 8). The ALARA category was given a scaling factor or 0.2 to account for the reduced long-term personnel dose which will accompany reduced maintenance and inspection requirements (0.2 x 9).

Economic Aspects: After initial upgrades have been made on the Unit 2 HPCI skid there will be a reduction in long-term maintenance and inspection costs.

Related Standards: This project relates to the Work Management Policy for material condition.

Other Considerations: This project will require that the work be accomplished during an outage. Upgrading the HPCI skid will have to be coordinated with other work in the area like the residual heat removal (RHR) and HCPI refurbishment and painting project, P0057D.

III. CONCLUSION

Completion of the HPCI skid upgrade will improve maintenance and inspection of the HPCI turbine and pump. This upgrade will be done by the end of refueling outage B213R1. The improved maintenance and inspection will mean a reduction in both the time and dose required to perform these tasks.