05000445/LER-2017-001, Regarding Unanalyzed Condition Involving Teflon Installed in Containment Spray Pump Diaphragm Seal Assemblies
| ML17102B413 | |
| Person / Time | |
|---|---|
| Site: | Comanche Peak  |
| Issue date: | 03/13/2017 |
| From: | Dreyfuss J Luminant Power, Vistra Operations Company |
| To: | Document Control Desk, Office of Nuclear Reactor Regulation |
| References | |
| CP-201700143, TXX-17025 LER 17-001-00 | |
| Download: ML17102B413 (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)(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)(i)(B), Prohibited by Technical Specifications 10 CFR 50.73(a)(2)(vii), Common Cause Inoperability 10 CFR 50.73(a)(2)(i) |
| 4452017001R00 - NRC Website | |
text
a Luminant CP-201700143 TXX-17025 March 13, 2017 U.S. Nuclear Regulatory Commission Attention: Document Control Desk Washington, DC 20555-0001 John R. Dreyfuss Plant Manager John.Dreyfuss@luminant.com Ref:
SUBJECT:
COMANCHE PEAK NUCLEAR POWER PLANT DOCKET NOS. 50-445 AND 50-446 Luminant Power P 0 Box 1002 6322 North FM 56 Glen Rose, TX 76043 T 254 897 5200 c 802 380 0894 F 2548970410 10 CFR50.73 UNANALYZED CONDITION INVOLVING TEFLON INSTALLED IN CONTAINMENT SPRAY PUMP DIAPHRAM SEAL ASSEMBLIES LICENSEE EVENT REPORT 445/17-001-00
Dear Sir or Madam:
Pursuant to 10CFR50.73, Vistra Operations Company LLC ("Vistra OpCo") hereby submits enclosed Licensee Event Report (LER) 445/17-001-00, "Unanalyzed Condition Involving Teflon Installed In Containment Spray Pump Diaphragm Seal Assemblies," for Comanche Peak Nuclear Power Plant (CPNPP) Units 1 and 2. Should you have any questions, please contact Mr. Gary Merka at (254) 897-6613.
Enclosure c - Kriss Kennedy, Region IV Margaret M. Watford, NRR Resident Inspectors, Comanche Peak Sincerely,
NRC FORM 366 U.S. NUCLEAR REGULATORY COMMISSION APPROVED BY OMB: NO. 3150-0104 EXPIRES: 10/31/2018 (06-2016)
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 />.
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Reported lessons learned are incorporated into the licensing process and fed back to industry.
LICENSEE EVENT REPORT (LER)
Send comments regarding burden estimate to the FOIA, Prtvacy and Information Collections t.
Branch (T-5 F53), U.S. Nuclear Regulatory Commission, Washington, DC 20555-0001, or by e-mail I
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(See Page 2 for required number of digits/characters for each block) to lnfocollects.Resource@nrc.gov, and to the Desk Officer, Office of Information and Regulatory Affairs, NEOS-10202, (3150-0104), Office of Management and Budget, Washington, DC 20503. If a (See NUREG-1022, R.3 for instruction and guidance for completing this form means used to impose an information collection does not display a currently valid OMB control http://www.nrc.gov/reading-rm/doc-collectionslnuregs/staff/sr1022/r3l) number, the NRG may not conduct or sponsor, and a person is not required to respond to, the information collection.
- 3. PAGE Comanche Peak Nuclear Power Plant 05000 445 1 OF 3
- 4. TITLE Unanalyzed Condition Involving TEFLON Installed in Containment Spray Pump Diaphragm Seal Assemblies
- 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 CPNPPUnit2 446 05000 FACILITY NAME DOCKET NUMBER 01 11,
17 17 -
001 -
00 03 13 17 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)
D 50.73(a)(2)(ii)(A)
D 50.73(a)(2)(viii)(A) 1 D 20.2201(d)
D 20.2203(a)(3)(ii)
[{] 50.73(a)(2)(ii)(B)
D 50.73(a)(2)(viii)(B)
D 20.2203(a)(1)
D 20.2203(a)(4)
D so.13(a)(2)(iii)
D 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)
- 10. POWER LEVEL D 20.2203(a)(2)(ii)
D 50.36(c)(1)(ii)(A)
D 50.73(a)(2)(v)(A)
D 13.11(a)(4)
D 20.2203(a)(2)(iii)
D so.3a(c)(2)
D 50.73(a)(2)(v)(B)
D 13.11(a)(s)
D 20.2203(a)(2)(iv)
D so.4a(a)(3)(ii)
[{] 50.73(a)(2)(v)(C)
D 13.77(a)(1) 100 D 20.2203(a)(2)(v)
D 50.73(a)(2)(i)(A)
[{] 50.73(a)(2)(v)(D)
D 73.77(a)(2)(i)
D 20.2203(a)(2)(vi)
[{] 50.73(a)(2)(i)(B)
[{] 50.73(a)(2)(vii)
D 13.11(a)(2)(ii)
D 50.73(a)(2)(i)(C)
D OTHER Specify in Abstract below or in SUMMARY. OF THE EVENT, INCLUDING DATES AND APPROXIMATE TIMES:
On September 16, 2016, Comanche Peak Nuclear Power Plant (CPNPP) reported an unanalyzed condition and potential loss of safety function per 10CFR 50.72(b)(3)(ii)(B) and 10CFR50.72(b)(3)(v) related to TEFLON (PTFE) installed in the pressure gauge diaphragm seal assemblies for all four of the Centrifugal Charging Pumps and both of the Positive Displacement Charging Pt.imps on Units 1 and 2 (EN#52244). On November 14, 2016, this event was subsequently retracted.
On December 12, 2016, during the extent of condition review, TEFLON was also found to be installed in the suction and discharge pressure gauge diaphragm seal assemblies for the Unit 1 and 2 Containment Spray Pumps [EllS:(BE)(PI)
(SEAL)].
On January 11, 2017 at approximately 1500, an evaluation was completed that determined reasonable assurance did not exist that the Containment Spray system would have been able to fulfill its design function of removing heat from the containment environment without impacting the applicable dose limits. TEFLON is a restricted mat~rial normally prohibited from use in contact with reactor coolant or in radiation environments. TEFLON is not radiation tolerant and degrades in a radiation environment. The TEFLON used in these diaphragm seal assemblies could fail during a postulated Loss of Coolant Accident (LOCA) which could cause the Containment Spray systems on Units 1 and 2 to be inoperable, and exceed system leakage limits. This could challenge dose limits and in plant post-accident accessibility.
This represents an unanalyzed condition. The TEFLON has likely existed in these diaphragm seals since initial plant licensing. The pressure gauges and diaphragm seals for all of the Unit 1 and 2 Containment Spray pumps have been isolated and the Unit 1 and 2 Containment Spray systems are currently operable.
E. THE METHOD OF DISCOVERY OF EACH COMPONENT OR SYSTEM FAILURE, OR PROCEDURAL PERSONNEL ERROR The TEFLON was discovered in the Unit 1 and 2 Containment Spray pump diaphragm seal assemblies during an extent of condition review by Engineering (Utility, Non Licensed) personnel.
II. COMPONENT OR SYSTEM FAILURES A. CAUSE OF EACH COMPONENT OR SYSTEM FAILURE The component and system failure cause will be provided in a supplemental report.
B. FAILURE MODE, MECHANISM, AND EFFECTS OF EACH FAILED COMPONENT The failure mode, mechanism, and effects will be provided in a supplemental report.
C. SYSTEMS OR SECONDARY FUNCTIONS THAT WERE AFFECTED BY FAILURE OF COMPONENTS WITH MULTIPLE FUNCTIONS Systems or secondary functions that were affected will be provided in a supplemental report.
D. FAILED COMPONENT INFORMATION
Failed component information will be provided in a supplemental report.
Ill. ANALYSIS OF THE EVENT A. SAFETY SYSTEM RESPONSES THAT OCCURRED Not applicable -No safety system responses occurred as a result of this event.
B. DURATION OF SAFETY SYSTEM TRAIN INOPERABILITY The Unit 1 and 2 Containment Spray systems were inoperable since initial licensing (April 17, 1990 for Unit 1 and April 6, 1993 for Unit 2).
C. SAFETY CONSEQUENCES AND IMPLICATIONS OF THE EVENT The pressure gauges and diaphragm seals for all of the Unit 1 and 2 Containment Spray Pumps have been isolated and the Unit 1 and 2 Containment Spray systems are currently operable. This event involved past inoperability of the Unit 1 and 2 Containment Spray Systems. Since no accidents involving the Containment Spray system have occurred since initial licensing, there were no actual safety consequences for this event. This is a postulated event and the risk associated with this issue was very low and the safety of the environment or general population was not threatened. This event has been evaluated to meet the definition of a safety system functional failure per 10CFR50.73(a)(2)(v).
IV. CAUSE OF THE EVENT
The cause of this event is still being determined and a supplemental report providing this information will be submitted by May 25, 2017.
V. CORRECTIVE ACTIONS
Interim corrective actions include isolating the pressure gauges and diaphragm seals for all of the Unit 1 and 2
~Containment Spray Pumps. The corrective actions for this event are still being determined and a supplemental report providing this information will be submitted by May 25, 2017.
VI. PREVIOUS SIMILAR EVENTS
There have been no previous similar reportable events at CPNPP in the last three years. Page 3
of 3