ML18194A800

Engineered Safety Feature Pump Room Exhaust Air Cleanup System Failure Resulting in a Condition Prohibited by Technical Specifications

ML18194A800
Person / Time
Site:	Palo Verde
Issue date:	07/12/2018
From:	Lacal M Arizona Public Service Co
To:	Document Control Desk, Office of Nuclear Reactor Regulation
References
102-07737-MLL/SPD IR 2018004
Download: ML18194A800 (4)

Text

Oaps 102-07737-MLLySPD July 12, 2018 ATTN: Document Control Desk U.S. Nuclear Regulatory Commission Washington, DC 20555-0001 10 CFR 50.73 MARIA L. LACAL Senior Vice President Nuclear Regulatory and Oversight Palo Verde Nuclear Generating Station P.O. Box 52034 Phoenix, AZ 85072 Maii Station 7605 Tel 623 393 6491

Subject:

Palo Verde Nuclear Generating Station (PVNGS) Unit 1 Docket No. STN 50-528 / License No. NPF 74 Licensee Event Report 2018-004-00 Enclosed please find Licensee Event Report (LER) 50-528/2018-004-00 that has been prepared and submitted pursuant to 10 CFR 50.73. This LER reports an Engineered Safety Feature Pump Room Exhaust Air Cleanup System Air Filtration Unit that was inoperable longer than allowed by Technical Specifications.

In accordance with 10 CFR 50.4, copies of this LER are being forwarded to the Nuclear Regulatory Commission (NRC) Regional Office, NRC Region IV, and the Senior Resident Inspector.

Arizona Public Service Company makes no commitments in this letter. If you have questions regarding this submittal, please contact Matthew Kura, Nuclear Regulatory Affairs Department Leader, at (623) 393-5379.

Sincerely, MLL/SPD Enclosure cc:

K. M. Kennedy M. D. Orenak C. A. Peabody NRC Region IV Regional Administrator NRC NRR Project Manager for PVNGS NRC Senior Resident Inspector PVNGS A member of the STARS Alliance LLC Callaway

• Diablo Canyon

• Palo Verde

• Wolf Creek

NRC FORM 366 (04-2018)

U.S. NUCLEAR REGULATORY COMMISSION LICENSEE EVENT REPORT (LER)

_ i (See Page 2 for required number of digits/characters for each btock)

/ (SeeNUREG-1022, R.3 for instruction and guidance for completing this form httD://www.nrc.Qov/readinQ-mVcloo-collections/nuiBQa<sla>iysn022/13/)

APPROVED BY OMB: NO. 3150-0104 EXPIRES: 03/31/2020 Estimated burden per response to comply with this mandatory collection request: 80 hours9.259259e-4 days <br />0.0222 hours <br />1.322751e-4 weeks <br />3.044e-5 months <br />.

Reported lessons learned are incorporated into the licensing process and fed back to industry. Send comments regarding burden estimate to the Information Services Branch (T-2 F43), U S. Nuclear Regulatory Commission, Washington, X 20555-0001, or by e-mail to lnfocollects.Resoutce@nrc,gov, and to the Desk Officer, Office of Information and Regulatory Affairs, NEOB-10202, (31500104), Office of Management and Budget, Washington, X 20503. If a means used to impose an infonnation collection does not display a cunently valid OMB control number, the NX may not conduct or sponsor, and a person is not required to respond to, the inIbrmaCon collection.

1. Facility Name Palo Verde Nuclear Generating Station (PVNGS) Unit 1

2. Docket Number 05000528

3. Page 1 OF 3

4. Title Engineered Safety Feature Pump Room Exhaust Air Cleanup System Failure Resulting in a Condition Prohibited by Technical Specifications

5. Event Date Month Year 2018

6. LER Number Year 2018 Sequential Number 004 Rev No.

7. Report Date Month Year 2018

8. Other Facilities involved Facility Name Docket Number 05000 Facility Name Docket Number 05000 a operating Mode 1

11. This Report is Submitted Pursuant to 1lie Requirements of 10 CFR§: (Check all that apply) 20.2201(b) 20.2203(a)(3)(i) 50.73(a)(2)(ii)(A) 50.73(a)(2)(viii)(A) 20.2201(d) 20.2203(a)(3)(ii) 50.73(a)(2)(ii)(B) 50.73(a)(2)(viii)(B) 20.2203(a)(1) 20.2203(a)(4) 50.73(a)(2)(iii) 50.73(a)(2)(ix)(A) 20.2203(a)(2)(i) 50.36(c)(1)(i)(A) 50.73(a)(2)(iv)(A) 50.73(a)(2)(x)

10. Power Level 100 20.2203(a)(2)(ii) 50.36(c)(1)(ii)(A) 50.73(a)(2)(v)(A) 73.71(a)(4) 20.2203(a)(2)(iii) 50.36(c)(2) 50.73(a)(2)(v)(B) 73.71(a)(5) 20.2203(a)(2)(iv) 50.46(a)(3)(ii) 50.73(a)(2)(v)(C) 73.77(a)(1) 20.2203(a)(2)(v) 50.73(a)(2)(i)(A) 50.73(a)(2)(v)(D) 73.77(a)(2)(H) 20.2203(a)(2)(vi)

El 50.73(a)(2)(i)(B) 50.73(a)(2)(vii) 73.77(a)(2)(iii) 50.73(a)(2)(i)(C)

Other (Specify in Abstract below or in NRC Form 366A

12. Licensee Contact for this LER Licensee Contact Matthew Kura, Department Leader, Nuclear Regulatory Affairs relephone Number (Indude Mea Cade) fe23-393-5379

13. Complete One Line for each Component Failure Described in this Report Cause System Component Manufacturer Reportable To ICES Cause System Component Manufacturer Reportable To ICES X

VG FLT C733 Y

14. Supplemental Report Expected

15. Expected Submission Date Month Day Year

^ Yes (Ifyes, complete 15. Expected Submission Date) No 8

31 2018 Abstract (Limit to 1400 spaces, i.e., approximately 14 single-spaced typewritten lines)

On May 17, 2018, PVNGS Unit 1 received "A" train (1A) Engineered Safety Feature (ESF) Pump Room Exhaust Air Cleanup System (PREACS) Air Filtration Unit (AFU) carbon sample test results that exceeded the acceptance criteria of the Technical Specification (TS) Ventilation Filter Testing Program. The Unit 1 Control Room (CR) staff declared the AFU noperable and entered TS Limiting Condition for Operation (LCO) 3.7.13, ESF PREACS. The carbon filter replacement and testing was completed on May 18, 2018, and the Unit 1 CR staff declared the 1A ESF PREACS AFU operable.

The 1A ESF PREACS AFU was inoperable since the date the initial carbon sample was drawn on May 10, 2018. The duration exceeded the Required Action Completion Time for Conditions A and B of LCO 3.7.13 that expired on May 17, 2018. The event investigation is still in progress and the results will be reported in a supplement to this Licensee Event Report.

PVNGS reported a similar event on September 19, 2016, due to a Unit 3 Control Room Essential Filtration System (CREFS) AFU carbon sample test result exceeding acceptance criteria resulting in a condition prohibited by TS LCO 3.7.11, CREFS (LER 2016-001-00).

NRC FORM 366 (04-2018)

NRC FORM 366A (04-2018)

U.S. NUCLEAR REGULATORY COMMISSION LICENSEE EVENT REPORT (LER)

CONTINUATION SHEET (See NUREG-1022, R.3 for instruction and guidance for completing this form httD://www.nrc.Qov/readirxi-rm/doc-collections/nureas/staff/srin?2/r3/>

APPROVED BY OMB: NO. 3150-0104 EXPIRES: 3/31/2020 Estimated burden per response to comply with this mandatory collection request 80 hours9.259259e-4 days <br />0.0222 hours <br />1.322751e-4 weeks <br />3.044e-5 months <br />. Reported lessons learned are incorporated Into the licensing process and fed back to industry. Send comments regarding burden estimate to the Information Services Branch (T-2 F43), U.S. Nuclear Regulatory Commission, Washington, tx:

20555-0001, or by e-mail to lnfocollects.Resource@nrc.gov, and to the Desk Officer, Office of Information and Regulatory Affairs, NEOB-10202, (3150-0104), Office of Management and Budget Washington, DC 20503. If a means used to impose an infomiation collection does not display a currently valid OMB control number, the NRC may not conduct or sponsor, and a person Is not required to respond to, the information collection.

1. FACILITY NAME Z DOCKET NUMBER a LERNUMBER Palo Verde Nuclear Generating Station (PVNGS) Unit 1 05000-528 YEAR 2018 SEQUENTIAL NUMBER

-004 REV NO.

-00 NARRATIVE All times are Mountain Standard Time and approximate unless otherwise indicated.

1. REPORTING REQUIREMENT(S):

This Licensee Event Report (LER) is being submitted pursuant to 10 CFR 50.73(a)(2)(i)(B) to report a condition prohibited by Technical Specification (TS) Limiting Condition for Operation (LOO) 3.7.13, Engineered Safety Feature (ESF) Pump Room Exhaust Air Cleanup System (PREACS)(EIIS:VG). PVNGS Unit 1 received "A" train (1 A) ESF PREACS Air Filtration Unit (AFU) carbon sample test results that exceeded TS 5.5.11, Ventilation Filter Testing Program (VFTP) acceptance criteria on May 17, 2018, for a sample obtained on May 10, 2018.

The 1A ESF PREACS AFU was inoperable since May 10, 2018, which exceeded the Required Action Completion Time for Conditions A and B of LCO 3.7.13 that expired on May 17, 2018.

The event investigation is still in progress and the results will be reported in a supplement to this Licensee Event Report.

2. DESCRIPTION OF STRUCTURE(S), SYSTEM(S) AND COMPONENT(S):

Two separate heating, ventilation, and air conditioning (HVAC) systems are provided for the Fuel Building. The normal system is a once-through air system and functions during normal plant operation only. The essential system is a filtered exhaust system and functions only in the event of a fuel handling accident, a loss of coolant accident (LOCA), or during required testing.

The Fuel Building HVAC system is designed to maintain an environment to ensure the operability of Fuel Building equipment and to provide the required ventilation to maintain the level of airborne radioactivity below permissible limits.

The Fuel Building and Auxiliary Building Essential AFUs are designed to exhaust the Fuel Building air during a fuel handling accident and maintain the building at a slight negative pressure to avoid spread of radioactive contamination. These AFUs also provide filtration for the essential pump rooms (PREACS function), located below the 100 foot elevation of the Auxiliary Building, during a LOCA and maintain them at slight negative pressure compared to the adjacent areas.

The Fuel Building and Auxiliary Building Essential AFUs are designed with a fan, pre-filter, two High-Efficiency Particulate Air (HEPA) filters and a carbon adsorption filter. The purpose of the carbon filter is to filter out radioiodine during postulated accident situations via a chemical reaction between the iodine and the activated carbon.

The carbon is tested every 18 months in accordance with TS Surveillance Requirements. This surveillance requirement involves sending a representative carbon sample to a laboratory fortesting per ASTM D3803-1989, Standard Test Method for Nuclear-Grade Activated Carbon.

Technical Specification LCO 3.7.13 requires two ESF PREACS trains be operable during Modes 1, 2, 3, and 4. The Required Action for Condition A, for a single inoperable train, specifies restoration of the inoperable train within 7 days. Condition B requires entry into Mode 3 within 6 hours6.944444e-5 days <br />0.00167 hours <br />9.920635e-6 weeks <br />2.283e-6 months <br /> and be in Mode 5 within 36 hours4.166667e-4 days <br />0.01 hours <br />5.952381e-5 weeks <br />1.3698e-5 months <br /> if the Required Action and associated completion time is not met.

NRC FORM 366A (04-2018)

Page 2 of 3

NRC FORM 366A (04^2018)

U.S. NUCLEAR REGULATORY COMMISSION LICENSEE EVENT REPORT (LER)

CONTINUATION SHEET (See NUREG-1022, R.3 for instruction and guidance for compieting this form httD://www.nrc.QOV/readinQ-tm/doc-collections/nureQs/staff/sr1022/r3/)

APPROVED BY OMB: NO. 3150-0104 EXPIRES; 3/31/2020 Estimated burden per response to comply with this mandatory collection request: 80 hours9.259259e-4 days <br />0.0222 hours <br />1.322751e-4 weeks <br />3.044e-5 months <br />. Reported lessons learned are incorporated into the licensing process and fed back to industry. Send comments regarding burden estimate to the Information Services Branch {T-2 F43), U.S. Nuclear Regulatory Commission, Washington, DC 20555-0001, or by e-mail to lnfocollects.Resource@nrc.gov, and to the Desk Officer, Office of Information and Regulatory Affairs, NEOB-10202, (3150-0104), Office of Management and Budget, Washington, DC 20503. If a means used to impose an information collection does not display a currently valid OMB control number, the NRC may not conduct or sponsor, and a person Is not required to respond to, the information collection.

1. FACILITY NAME Z DOCKET NUMBER

3. LERNUMBER Palo Verde Nuclear Generating Station 05000-528 YEAR SEQUENTIAL NUMBER REV NO.

(PVNGS) Unit 1 2018

-004

-00

3. INITIAL PLANT CONDITIONS:

On May 17, 2018, PVNGS Unit 1 was in Mode 1 (Power Operation), at 100 percent power, normal operating temperature and pressure. There were no other structures, systems, or components out of service that contributed to this event.

4. EVENT DESCRIPTION:

On May 17, 2018, PVNGS Unit 1 received "A" train (1A) ESP PREACS AFU carbon sample test results that exceeded the acceptance criteria of the TS VFTP. The Unit 1 Control Room (CR) staff declared the AFU inoperable and entered TS Limiting Condition for Operation (LCO) 3.7.13, ESF PREACS.

The initial sample result departed from the expected carbon efficiency trend and a second carbon sample was obtained on May 17, 2018, and sent offsite for testing. The results of the second sample test were received on May 19, 2018, and this sample also exceeded the TS VFTP acceptance criteria. The carbon filter replacement and testing was completed on May 18, 2018 and the Unit 1 CR staff declared the 1A ESF PREACS AFU operable.

The 1A ESF PREACS AFU was inoperable since May 10, 2018, which exceeded the Required Action Completion Time for Conditions A and B of LCO 3.7.13 that expired on May 17, 2018.

5. ASSESSMENT OF SAFETY CONSEQUENCES:

This event did not result in a potential transient more severe than those analyzed in the Updated Final Safety Analysis Report (UFSAR) or result in an abnormal release of radioactive materials to the environment. There were no actual safety consequences as a result of this event and the event did not adversely affect the health and safety of the public.

6. CAUSE OF THE EVENT:

The event investigation is still in progress, and the results will be reported in a supplement to this Licensee Event Report.

7. CORRECTIVE ACTIONS:

As an immediate corrective action, the 1A ESF PREACS AFU carbon filter was replaced, testing was completed, and the system was declared operable on May 18, 2018. The event investigation is still in progress. Additional corrective actions, as determined by the cause evaluation, will be reported in a supplement to this Licensee Event Report.

8. PREVIOUS SIMILAR EVENTS:

PVNGS reported a similar event on September 19, 2016, due to a Unit 3 Control Room Essential Filtration System (CREFS) AFU carbon sample test result exceeding acceptance criteria resulting in a condition prohibited by TS LCO 3.7.11, CREFS (LER 2016-001-00).

NRC FORM 366A (04-2018)

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