05000249/FIN-2017003-01
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Finding | |
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| Title | Granted Notice of Enforcement Discretion 173001: LCO 3.1.7 Required Action B.1 per TS 3.1.7, Standby Liquid Control System |
| Description | Inspection Scope The inspectors reviewed the licensees response to and assessment of a through- wall leak that developed on the Unit 3 SLC A pump discharge piping . Specifically, on September 12, 2017, during a system operational pressure test, licensee personnel observed a through- wall leak from the forged body of a 1.5 stainless steel pipe T in the Unit 3 SLC system. The affected component is a part of the ASME Code Class 2 boundary. Due to the piping being ASME Code Class 2, it was required to be immediately isolated in accordance with Technical Requirements Manual 3.4.a, Structural Integrity. Isolating this piping resulted in both trains of the Unit 3 SLC system becoming inoperable as the leak was unisolable from both pumps. With both trains inoperable, the licensee entered Limiting Condition for Operation ( LCO ) 3.1.7, Required Action B.1 which requires the restoration of at least one train of SLC within 8 hours9.259259e-5 days <br />0.00222 hours <br />1.322751e-5 weeks <br />3.044e-6 months <br />. 15 The inspectors examined the sites actions to uncover the issue with the Unit 3 SLC system , their actions to address the issue once it was identified, and their compensatory actions associated with the receipt of the Notice of Enforcement Discretion ( NOED ). The inspectors also reviewed licensee documents to verify that information contained in the NOED request was accurate. Inspection activities included gathering additional information regarding the licensees bases for requesting the NOED; examining the sites decision -making process for the issue; reviewing the licensees condition evaluation; observing the licensees compensatory actions; and evaluating the licensees operability determination. To correct this issue and exit the NOED, the licensee completed replacement of the affected Unit 3 pipi ng and connections, satisfactorily tested the replaced components, and declared the Unit 3 SLC system operable. Documents reviewed are listed in the Attachment. This event follow up review constituted one sample as defined in IP 71153 05. b. Findings Introduction : The inspectors opened an unresolved item associated with a potential noncompliance with TS 3.1.7 Required Action B.1 that occurred on September 12, 2017. NOED 17 3001 was granted by the NRC staff agreeing not to enforce compliance with the TS completion time for an additional 35 hours4.050926e-4 days <br />0.00972 hours <br />5.787037e-5 weeks <br />1.33175e-5 months <br />. Description : On September 10, 2017, with the Unit 3 SLC system in standby operation, an equipment operator performing rounds noted sodium pentaborate crystallization build -up under piping insulation. The licensee removed the insulation from the potential leak location, and noted a dry sodium pentaborate stain on the back of a forged piping T on the 1.5 stainless steel discharge line of the A SLC pump. The licensee Shift Manager made an immediate operability determination of operable based on the dry nature of the stain and its location being on a forged body , and not at a connection or weld location. The licensees initial evaluation surmised the stain was historical in nature and was from an adjacent valve packing leak. In the event that further investigation of the stain indicated a through -wall leak, the licensee investigated American Society of Mechanical Engineers ( ASME ) code compliant permanent and temporary repair options, to include the construction of an Engineered Clamp. This method was eventually dismissed as supports required for the clamp would have been impractical based on system configuration. On September 12, 2017, the licensee cleaned the stain off of the piping T and performed a visual inspection for leakage with the system at full operating pressure. During this test, a leak was observed emanating from the body of the piping T. Due to the leak occur ring within the ASME Code Class 2 boundary, the licensee was required to isolate it in accordance with Technical Requirements Manual 3.4.a, Structural Integrity. Isolating this piping resulted in both trains of the Unit 3 SLC system becoming inoperable, and therefore the licensee entered LCO 3.1.7, Required Action B.1, with an 8 hour9.259259e-5 days <br />0.00222 hours <br />1.322751e-5 weeks <br />3.044e-6 months <br /> required action. With a through wall leak discovered and the plant in a short duration shutdown LCO, the licensee implemented a repair plan for a permanent piping replacement and requested a NOED from the NRC to complete repairs prior to entering Required Action C.1 and C.2, which require placing the Unit in Mode 3 (hot shutdown) and Mode 4 (cold shutdown) within 12 and 36 hours4.166667e-4 days <br />0.01 hours <br />5.952381e-5 weeks <br />1.3698e-5 months <br /> , respectively. The NRC granted a NOED for an additional 35 hours4.050926e-4 days <br />0.00972 hours <br />5.787037e-5 weeks <br />1.33175e-5 months <br /> at 5:46 p.m. on September 12, 2017. Consistent with NRC policy, the NRC agreed not to enforce 16 compliance with the specific TSs in this instance, but will further review the cause(s) that created the apparent need for enforcement discretion to determine whether there is a performance deficiency, if the issue is more than minor, or if there is a violation of requirements. This issue will be tracked as an unresolved item. (Unresolved Item 05000249/2017003 01, Granted Notice of Enforcement Discretion 17 3001: LCO 3.1.7 Required Action B.1 per TS 3.1.7, Standby Liquid Control System ) |
| Site: | Dresden  |
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| Report | IR 05000249/2017003 Section 4OA3 |
| Date counted | Sep 30, 2017 (2017Q3) |
| Type: | URI: Severity level Enforcement Discretion |
| cornerstone | Mitigating Systems |
| Identified by: | NRC identified |
| Inspection Procedure: | IP 71153 |
| Inspectors (proximate) | G Roach R Elliott M Bielby J Cameron |
| INPO aspect | |
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Finding - Dresden - IR 05000249/2017003 | |||||||||||||||||||||||||||||||||||||||||||
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Finding List (Dresden) @ 2017Q3
Self-Identified List (Dresden)
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