05000298/LER-1917-005, Regarding Traversing In-core Probe In-shield Limit Switch Mounting Failure Results in Common Cause Lnoperability of Independent Trains or Channels and Condition Prohibited by Technical Specifications
| ML17236A166 | |
| Person / Time | |
|---|---|
| Site: | Cooper  |
| Issue date: | 08/17/2017 |
| From: | Dent J Nebraska Public Power District (NPPD) |
| To: | Document Control Desk, Office of Nuclear Reactor Regulation |
| References | |
| NLS2017077 LER 17-005-00 | |
| Download: ML17236A166 (4) | |
| Event date: | |
|---|---|
| Report date: | |
| Reporting criterion: | 10 CFR 50.73(a)(2)(ii)(A), Seriously Degraded 10 CFR 50.73(a)(2)(viii)(A) 10 CFR 50.73(a)(2)(ii)(B), Unanalyzed Condition 10 CFR 50.73(a)(2)(ii) 10 CFR 50.73(a)(2)(ix)(A) 10 CFR 50.73(a)(2)(iv)(A), System Actuation 10 CFR 50.73(a)(2)(v)(A), Loss of Safety Function - Shutdown the Reactor 10 CFR 50.73(a)(2)(v)(B), Loss of Safety Function - Remove Residual Heat 10 CFR 50.73(a)(2)(v), Loss of Safety Function 10 CFR 50.73(a)(2)(i)(A), Completion of TS Shutdown 10 CFR 50.73(a)(2)(i)(B), Prohibited by Technical Specifications 10 CFR 50.73(a)(2)(vii), Common Cause Inoperability 10 CFR 50.73(a)(2)(i) |
| 2981917005R00 - NRC Website | |
text
Nebraska Public Power District
Always there when you need us" NLS2017077 August 17, 2017 U.S. Nuclear Regulatory Commission Attention: Document Control Desk Washington, D.C. 20555-0001
Subject:
Licensee Event Report No. 2017-005-00 Cooper Nuclear Station, Docket No. 50-298, DPR-46
Dear Sir or Madam:
The purpose of this correspondence is to forward Licensee Event Report 2017-005-00.
There are no new commitments contained in this letter.
Sincerely, K r\\p!\\,J\\ pl- "" fw-Cf C) h h. ~
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John Dent, Jr.
Vice President Nuclear-Chief Nuclear Officer
/lb Attachment: Licensee Event Report 2017-005-00 cc:
Regional Administrator w/attachment USNRC - Region IV Cooper Project Manager w/attachment USNRC - NRR Plant Licensing Branch IV Senior Resident Inspector w/attachment USNRC-CNS SRAB Administrator w/attachment NPG Distribution w/attachment INPO Records Center w/attachment via ICES entry SORC Chairman w/attachment CNS Records w/attachment COOPER NUCLEAR STATION P. 0. Box 98 I Brownville, NE 68321-0098 Telephone: (402) 825-3811 I Fax: (402) 825-5211 www.nppd.com
NRC FORM 366 U.S. NUCLEAR REGULATORY COMMISSION APPROVED BY OMB: NO. 3150-0104 EXPIRES: 0313112020 (04-2017)
, the NRC may not conduct or sponsor, and a person is not required to respond to, the information collection.
- 3. PAGE Cooper Nuclear Station 05000298 1 of 3
- 4. TITLE Traversing In-core Probe In-shield Limit Switch Mounting Failure Results in Common Cause lnoperability of Independent Trains or Channels and Condition Prohibited by Technical Specifications
- 5. EVENT DATE
- 6. LER NUMBER
- 7. REPORT DATE
- 8. OTHER FACILITIES INVOLVED YEAR ISEQUENTIALI REV FACILITY NAME DOCKET MONTH DAY YEAR NO.
MONTH DAY YEAR NUMBER 05000 FACILITY NAME DOCKET 06 22 17 2017 -
005 -
00 08 17 2017 05000
- 9. OPERATING MODE
- 11. THIS REPORT IS SUBMITTED PURSUANT TO THE REQUIREMENTS OF 10 CFR §: (Check all that apply)
D 20.2201(b)
D 20.2203(a)(3)(i) 0 50.73(a)(2)(ii)(A) 0 50.73(a)(2)(viii)(A) 1 D 20.2201(d)
D 20.2203(a)(3)(ii)
D 50.73(a)(2)(ii)(B)
D 50. 73(a)(2)(viii)(B)
D 20.2203(a)(1)
D 20.2203(a)(4)
D 50.73(a)(2)(ii)
D 50.73(a)(2)(ix)(A)
D 20.2203(a)(2)(i)
D 50.36(c)(1)(i)(A) 0 50.73(a)(2)(iv)(A)
D 50. 73(a)(2)(x)
D 20.2203(a)(2)(ii) 0 50.36(c)(1)(ii)(A) 0 50.73(a)(2)(v)(A)
D 73.71(a)(4)
- 10. POWER LEVEL D 20.2203(a)(2)(iii)
D 50.36(c)(2) 0 50.73(a)(2)(v)(B)
D 73.71(a)(5)
D 20.2203(a)(2)(iv)
D 50.46(a)(3)(ii) 0 50.73(a)(2)(v)(C)
D 73.77(a)(1) 100 0 20.2203(a)(2)(v) 0 50.73(a)(2)(i)(A)
D 50.73(a)(2)(v)(D)
D 73.77(a)(2)(i) 0 20.2203(a)(2)(vi)
~ 50.73(a)(2)(i)(B)
~ 50.73(a)(2)(vii)
D 73.77(a)(2)(ii)
D 50.73(a)(2)(i)(C) 0 OTHER Specify in Abstract below or in 050 00-298 YEAR 2017
- 3. LER NUMBER SEQUENTIAL NUMBER
- - 005 The valves were declared operable on July 13, 2017, at 1133, and TS LCO 3.6.1.3, Condition A, was exited.
BASIS FOR REPORT CNS is reporting these events under 10 CFR 50.73(a)(2)(vii) as common cause inoperability of independent trains or channels, as the primary containment isolation ball valves on TIPs C and D were inoperable at the same time. It is also being reported as a condition prohibited by Technical Specifications as defined in 10 CFR 50. 73(a)(2)(i)(B).
SAFETY SIGNIFICANCE
REV NO.
- - 00 There were no safety consequences associated with this condition. The potential safety significance of this event was low. The TIP ball valves are able to be closed by taking manual action to remove power in the case of a primary containment isolation signal. In addition, the TIP shear valves remained operable during the period of time the TIP ball valves were inoperable. The safety function of the primary containment isolation system was maintained. This condition did not cause an impact to the safety of the general public, nuclear safety, industrial safety, or radiological safety.
CAUSE
Inadequate mounting and securing of the in-shield limit switch to the chamber shield caused the limit switch to fail to actuate as designed.
CORRECTIVE ACTIONS
A Work Order was implemented to repair the mounting of the in-shield limit switches for all TIP channels.
In addition, the procedure for TIP chamber shield maintenance was revised to provide guidance for properly mounting the TIP in-shield limit switches.
PREVIOUS EVENTS CR-CNS-2016-02424 - On May 3, 2016, TIP B detector failed to stop at its in-shield position when being retracted back into its chamber shield. This failure was attributed to inadequate maintenance associated with mounting the limit switch to the chamber shield.
CR-CNS-2016-08539-0n November 29, 2016, TIP C detector failed to stop at its in-shield position when being retracted back into its chamber shield. This failure was attributed to inadequate maintenance associated with mounting the limit switch to the chamber shield. Page 3 of 3