ENS 44811
ENS Event | |
|---|---|
12:30 Jan 28, 2009 | |
| Title | High Pressure Coolant Injection System Inoperable |
| Event Description | On January 28, 2009 at 0730 the Division 2 Emergency Equipment Cooling Water System (EECW) was declared inoperable due to a blown control power fuse in the bucket for the P4400F604 - Div 2 EECW Supply to Control Rod Drive (CRD) pumps. This is a normally open valve and is required to close upon EECW initiation to remove non-essential loads. The blown control power fuse would have prevented this action from occurring. The ECCW System cools various safety related components including the High Pressure Coolant Injection (HPCI) System Area Cooler. An unplanned HPCI inoperability occurred due to the Division 2 EECW inoperability based on a loss of the HPCI System Area Cooler. A 14 day Limiting Condition for Operation (LCO) was entered for HPCI per LCO 3.5.1. The control power fuse was replaced, EECW and HPCI were declared operable, and LCO 3.5.1 exited on January 28, 2009 at 1025. This report is being made pursuant to 10CFR50.72(b)(3)(v)(D) as a condition that at the time of discovery could have prevented the fulfillment of a safety function needed to mitigate the consequences of an accident, based on loss of a single train safety system.
The NRC Resident Inspector has been notified.
The As-Found condition of the Division 2 Emergency Equipment Cooling Water (EECW) Control Rod Drive (CRD) Pump Supply Valve and High Pressure Coolant Injection (HPCI) System Room Cooler were evaluated. The HPCI System Room Cooler was operable with P4400-F604, Division 2 EECW to the CRD supply valve open. Based on an Engineering evaluation of EECW flow during a Loss of Coolant Accident (LOCA) and Non-LOCA conditions with the valve open, there is adequate flow margin in the EECW system. The HPCI Room Cooler had adequate cooling flow to perform its design function. The HPCI room temperature would have been maintained below the HPCI equipment room high temperature isolation setpoint. Additionally, plant procedures provide directions for bypassing the HPCI equipment room high temperature trip. Consequently, there was no loss of HPCI safety function. Declaring HPCI inoperable was conservative and based on initial considerations. Therefore, event notification 44811 is retracted. The Licensee notified the NRC Resident Inspector. Notified R3DO (Lara). |
| Where | |
|---|---|
Fermi  Michigan (NRC Region 3) | |
| Reporting | |
| 10 CFR 50.72(b)(3)(v)(D), Loss of Safety Function - Mitigate the Consequences of an Accident | |
| Time - Person (Reporting Time:+-0.23 h-0.00958 days <br />-0.00137 weeks <br />-3.15054e-4 months <br />) | |
| Opened: | Greg Miller 12:16 Jan 28, 2009 |
| NRC Officer: | Jason Kozal |
| Last Updated: | Mar 11, 2009 |
| 44811 - NRC Website | |
Unit 2 | |
|---|---|
| Reactor critical | Critical |
| Scram | No |
| Before | Power Operation (100 %) |
| After | Power Operation (100 %) |