05000482/LER-2018-001, Inappropriate Use of Blind Flange for Containment Isolation Valve Results in Condition Prohibited by Technical Specifications

Inappropriate Use of Blind Flange for Containment Isolation Valve Results in Condition Prohibited by Technical Specifications

ML18284A324
Person / Time
Site:	Wolf Creek
Issue date:	10/04/2018
From:	Bayer R Wolf Creek
To:	Document Control Desk, Office of Nuclear Reactor Regulation
References
WO 18-0041 LER 2018-001-00
Download: ML18284A324 (5)

LER-2018-001, Inappropriate Use of Blind Flange for Containment Isolation Valve Results in Condition Prohibited by Technical Specifications

Event date:
Report date:
Reporting criterion:	10 CFR 50.73(a)(2)(i)(B), Prohibited by Technical Specifications 10 CFR 50.73(a)(2)(viii)(A) 10 CFR 50.73(a)(2)(viii)(B) 10 CFR 50.73(a)(2)(ix)(A) 10 CFR 50.73(a)(2)(iv)(A), System Actuation 10 CFR 50.73(a)(2)(x) 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)(vii), Common Cause Inoperability 10 CFR 50.73(a)(2)(i)
4822018001R00 - NRC Website

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'NUCLEAR OPERATING CORPORATION Robert J. Bayer Plant Manager U. S. Nuclear Regulatory Commission ATTN: Document Control Desk Washington, DC 20555 October 4, 2018 WO 18-0041

Subject:

Docket No. 50-482: Licensee Event Report 2018-001-00, "Inappropriate Use of Blind Flange for Containment Isolation Valve Results in Condition Prohibited by Technical Specifications" To Whom It May Concern:

The enclosed Licensee Event Report (LER) 2018-001-00 is being submitted pursuant to 10 CFR 50.73(a)(2)(i)(B) as a condition prohibited by Technical Specifications.

This letter contains no commitments. If you have any questions concerning this matter, please contact me at (620) 364-4015, or Cynthia R. Hafenstine at (620) 364-4204.

RJB/rlt

Enclosure:

LER 2018-001-00 cc:

K. M. Kennedy (NRC), w/e B. K. Singal (NRC), w/e N. H. Taylor (NRC), w/e Senior Resident Inspector (NRC), w/e Sincerely, fft~

Robert J. Bayer P.O. Box 411 / Burlington, KS 66839 / Phone: (620) 364-8831 An Equal Opportunity Employer M/F/HCNET

NRCFORM366 U.S. NUCLEAR REGULATORY COMMISSION APPROVED BY 0MB: NO. 3150-0104 EXPIRES: 03/31/2020 (04-2018)

', the NRC may not conduct or sponsor, and a person is not required to respond to, the information collection.

3.Page Wolf Creek Generating Station 05000 482 1

OF 4

4. Title Inappropriate Use of Blind Flange for Containment Isolation Valve Results in Condition Prohibited by Technical Specifications

5. Event Date

6. LER Number

7. Report Date

8. Other Facilities Involved I

Sequential I Rev Facility Name Docket Number Month Day Year Year Number No.

Month Day Year 05000 Facility Name Docket Number 05 15 2018 2018 -

001 -

00 10 04 2018 05000

9. Operating Mode

11. This Report is Submitted Pursuant to the Requirements of 1 O CFR §: (Check all that apply)

D 20.2201(b>

D 20.2203(a)(3)(i)

D 50. 73(a)(2)(ii)(A)

D 50.73(a)(2)(viii)(A)

D 20.2201(d)

D 20.2203(a)(3)(ii)

D 50. 73(a)(2)(ii)(B)

D 50.73(a)(2)(viii)(B) 4 D

D 20.2203(a)(1)

D 20.2203(a)(4),

D 50. 73(a)(2)(iii) 50.73(a)(2)(ix)(A)

D 20.2203(a><2>(i)

D 50.36(c)(1)(i)(A)

D 50.73(a)(2)(iv)(A)

D 50.73(a)(2)(x) 1 O. Power Level D 20.2203(a)(2)(ii)

D 50.36(c)(1 )(ii)(A)

D 50.73(a)(2)(v)(A)

D 73.71(a)(4)

D 20.2203(a)(2)(iii)

D 50.36(c)(2)

D 50.73(a)(2)(v)(B)

D 73.71(a)(5)

D 20.2203(a)(2)(iv)

D 50.46(a)(3)(ii)

D 50.73(a)(2)(v)(C)

D 73.77(a)(1)

NIA D 20.2203(a)(2)(v)

D 50.73(a)(2)(i)(A)

D 50.73(a)(2)(v)(D)

D 73.77(a)(2)(i)

D 20.2203(a)(2)(vi) 0 50.73(a)(2)(i)(B)

D 50.73(a)(2)(vii)

D 73.77(a)(2)(ii)

~D 50.73(a)(2)(i)(C)

D Other (Specify in Abstract below or in The individual testing identified that valve GTHZ0006 (containment shutdown purge supply side outside containment isolation valve) had a leak rate above that allowed by TS. The valve was declared inoperable and TS LCO 3.6.3 Condition D was entered at 0255 Central Daylight Time (CDT) on May 15, 2018. With the blind flanges installed, all of the other containment shutdown purge and minipurge supply side valves successfully passed the leakage rate testing.

Because this testing was performed close to the end of RF22, it was decided to leave the blind flanges installed in accordance with TS LCO 3.6.3, Required Action D.1 which requires that the affected flow path be isolated by use of at least one closed and de-activated automatic valve, closed manual valve, or blind flange. The plant was in Mode 5 at this point, but since LCO 3.6.3 is applicable in Modes 1, 2, 3, and 4, the completion of Required Action D.1 was necessary for the plant to enter Mode 4. The plant entered Mode 4 on May 15, 2018, at 0510 CDT.

On August 8, 2018, it was discovered that using a blind flange to meet the Required Actions for Condition D of TS LCO 3.6.3 is not allowed by Wolf Creek Nuclear Operating Corporation (WCNOC) procedure Al 26C-004, Technical Specification Application for Containment Isolation Valves. Step 6.2.2.6.c of this procedure states "Because they are non-safety related and non-seismic, the installed blind flanges cannot be used to satisfy LCO 3.6.3, Required Action D.1." So while TS LCO 3.6.3 would allow blind flanges to isolate the containment shutdown purge isolation valves, this would require the use of safety-related and seismically qualified flanges and piping. As such, on August 8, 2018, at 1545 CDT, WCGS re-entered TS LCO 3.6.3 Condition D to perform Required Action D.1. Required Action D.1 was completed at 1633 CDT on August 8 by ensuring that the inside containment shutdown purge and minipurge supply isolation valves were closed and de-energized.

REPORT ABILITY TS LCO 3.6.3 Condition D, Required Action D.1 has a Completion Time of 24 hours2.777778e-4 days <br />0.00667 hours <br />3.968254e-5 weeks <br />9.132e-6 months <br />. However, since the containment minipurge supply inside containment valve was not de-energized upon entry into Mode 4, Condition D existed for approximately 85 days (from May 15 when WCGS entered Mode 4 until August 8). Since this is longer than the allowed Completion Time for Required Action D.1, this event is being reported in accordance with 10 CFR 50.73(a)(2)(i)(B) as an operation or condition prohibited by TS.

It may also be noted that a violation of LCO 3.0.4.a occurred in connection with the plant entering a mode of applicability of LCO 3.6.3. With an LCO not met, LCO 3.0.4.a only permits entry into a mode of applicability of that LCO when the associated Required Actions to be entered permit continued operation in the applicable mode for an unlimited period of time. With Required Action D.1 of LCO 3.6.3 not actually being met, entry into Mode 4 wouldn't have been allowed.

CAUSE

This is a legacy issue. TS Bases 3.6.3 for Required Action D.1 was never updated to reflect that the blind flange currently allowed to be installed per sysiem design, could not be used to meet the Condition and Required Actions to isolate the penetration.

CORRECTIVE ACTIONS

Training was initiated for Operations personnel in both initial and requalification training to clarify that the blind flanges can not be used to meet Required Action D.1. A revision to the TS Bases 83.6.3 has been initiated to either remove the use of the currently designed blind flange, or add information that procedure Al 26C-004 needs to be reviewed. WC NOC is planning to submit a license amendment request at some point in the future to remove the use of a blind flange to meet TS LCO 3.6.3, Required Action D.1.

SAFETY SIGNIFICANCE

The safety significance of the event was low. The containment isolation function was maintained by the containment purge and minipurge supply inside containment isolation valves remaining shut. The total containment "as-found" minimum pathway leak rate remained within the limits of TS 3.6.1 during the time when the blind flange was installed.

OPERATING EXPERIENCE/PREVIOUS EVENTS None Page 4

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