ENS 52955
ENS Event | |
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16:30 Sep 8, 2017 | |
Title | Hpci System Inoperable |
Event Description | On September 8, 2017 at 1130 hours0.0131 days <br />0.314 hours <br />0.00187 weeks <br />4.29965e-4 months <br /> CDT, Unit Two High Pressure Coolant Injection (HPCI) Minimum Flow Valve MO 2-2301-14 flow indicating switch (FIS 2-2354) failed to meet the Technical Specification Allowable Value during calibration testing. Technical Specification Table 3.3.5.1-1 Allowable Value (3.f) requires greater than or equal to 634 gpm (3.14 inches water column as required by procedure). HPCI was subsequently declared inoperable.
This event is being reported as a condition that could have prevented fulfillment of a safety function in accordance with 10CFR50.72(b)(3)(v)(D). The HPCI system is a single train system and the loss of HPCI could impact the plant's ability to mitigate the consequences of an accident. The Reactor Core Isolation Cooling (RCIC) system was confirmed operable. Note: On September 8, 2017 at 1140 hours0.0132 days <br />0.317 hours <br />0.00188 weeks <br />4.3377e-4 months <br /> CDT, the HPCI Minimum Flow Valve MO 2-2301-14 flow indicating switch (FIS 2- 2354) was successfully recalibrated and HPCI was returned to Operable status. The NRC Senior Resident Inspector has been notified.
The purpose of this notification today (10/19/17) is to retract the ENS Report made on September 8, 2017 at 1545 hours0.0179 days <br />0.429 hours <br />0.00255 weeks <br />5.878725e-4 months <br /> CDT (ENS Report #52955). Upon further investigation, it was determined that a surveillance procedure contained an overly restrictive statement that directed operators to immediately declare the High Pressure Coolant Injection (HPCI) system inoperable when the HPCI Minimum Flow Valve MO 2-2301-14 flow indicating switch (FIS 2-2354) fails. This statement was in conflict with existing Technical Specification (TS) 3.3.5.1, Condition E, that allows seven days to restore the HPCI FIS (instrument channel only) to an operable status prior to entry into TS 3.3.5.1, Condition H, which requires declaring HPCI inoperable immediately. Hence, during the period of FIS inoperability (i.e., 10 minutes), the HPCI system was not required to be declared inoperable in accordance with Technical Specifications. Therefore, based on this information, ENS Report # 52955 is being retracted. Note: On September 8, 2017 at 1140 hours0.0132 days <br />0.317 hours <br />0.00188 weeks <br />4.3377e-4 months <br /> CDT, the HPCI Minimum Flow Valve MO 2-2301-14 flow indicating switch (FIS 2-2354) was successfully recalibrated and HPCI was returned to Operable status. The NRC Resident Inspector has been notified. Notified R3DO (Daley). |
Where | |
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Quad Cities Illinois (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:+0.25 h0.0104 days <br />0.00149 weeks <br />3.4245e-4 months <br />) | |
Opened: | Craig Vroman 16:45 Sep 8, 2017 |
NRC Officer: | Steve Sandin |
Last Updated: | Oct 19, 2017 |
52955 - NRC Website
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Unit 2 | |
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Reactor critical | Critical |
Scram | No |
Before | Power Operation (100 %) |
After | Power Operation (100 %) |