ENS Event | |
|---|---|
04:00 May 8, 2018 | |
| Title | |
| Event Description | On May 7, 2018 at 1041 CDT, Unit 1 performed an RCS (reactor coolant system) leakrate procedure that calculated an unidentified RCS leakrate of 0.202 gpm. The leak source investigation concluded at 2150 that the packing for the charging flow control valve (FCV) was the source of the RCS leakage when it was bypassed, which isolated the leakage. A second RCS leakrate calculation was performed after the charging flow control valve was isolated which calculated an acceptable leakrate of 0.00 gpm.
The packing leakage from the charging flow control valve represented leakage external to containment which would result in a greater that 5 Rem dose projection to control room personnel during accident conditions which does not satisfy the GDC19 criteria described in Technical Specification Bases 3.7.10. Therefore the control room emergency filtration system would not be able to fulfill its design function resulting in an unanalyzed condition. This condition is being reported pursuant to 10CFR50.72(b)(3)(ii) for a 'condition that results in the nuclear power plant being in an unanalyzed condition that significantly degrades plant safety'. The packing leak from the charging flow control valve will remain isolated until repaired under work order SNC944374. The NRC Resident Inspector has been notified. |
| Where | |
|---|---|
Farley  Alabama (NRC Region 2) | |
| Reporting | |
| 10 CFR 50.72(b)(3)(ii)(B), Unanalyzed Condition | |
| Time - Person (Reporting Time:+-2.35 h-0.0979 days <br />-0.014 weeks <br />-0.00322 months <br />) | |
| Opened: | Blake Mitchell 01:39 May 8, 2018 |
| NRC Officer: | Steven Vitto |
| Last Updated: | May 8, 2018 |
| 53392 - NRC Website
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Unit 1 | |
|---|---|
| Reactor critical | Not Critical |
| Scram | No |
| Before | Hot Standby (0 %) |
| After | Hot Standby (0 %) |
WEEKMONTHYEARENS 533922018-05-08T04:00:0008 May 2018 04:00:00
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