05000266/LER-1917-001, Regarding Control Room Barrier Inadvertently Disabled
| ML17320A010 | |
| Person / Time | |
|---|---|
| Site: | Point Beach  |
| Issue date: | 11/16/2017 |
| From: | Coffey B Point Beach |
| To: | Document Control Desk, Office of Nuclear Reactor Regulation |
| References | |
| NRC 2017-0051 LER 17-001-00 | |
| Download: ML17320A010 (4) | |
| Event date: | |
|---|---|
| Report date: | |
| Reporting criterion: | 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)(iii) 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) |
| 2661917001R00 - NRC Website | |
text
November 16, 2017 U. S. Nuclear Regulatory Commission ATTN: Document Control Desk Washington, DC 20555 Point Beach Nuclear Plant, Unit 1 and 2 Docket 50-266 and 50-301 Renewed License Nos. DPR-24 and DPR-27 Licensee Event Report 266/2017-001-00 Control Room Barrier Inadvertently Disabled NRC 2017-0051 10 CFR 50.73 Enclosed is Licensee Event Report (LER) 266/2017-001-00 for Point Beach Nuclear Plant, Unit 1 and 2. NextEra Energy Point Beach, LLC is providing this LER to report the event as an operation or condition prohibited by Technical Specifications, degraded or unanalyzed condition, and event or condition that could have prevented fulfillment of a safety function.
This letter contains no new regulatory commitments.
If you have any questions please contact Mr. Eric Schultz, Licensing Manager, at 920/755-7854.
Sincerely, NextEra Energy Point Beach, LLC Bob Coffey Site Vice President Enclosure cc:
Administrator, Region Ill, USNRC Project Manager, Point Beach Nuclear Plant, USNRC Resident Inspector, Point Beach Nuclear Plant, USNRC PSCW NextEra Energy Point Beach, LLC 6610 Nuclear Road, Two Rivers, WI 54241
NRC FORM 366 U.S. NUCLEAR REGULATORY COMMISSION APPROVED BY OMB: NO. 3150*0104 EXPIRES: 03/31/2020 (04*2017}
htt~ :/lwww. nrc. gov/read ing-rrnldoc-collections/nuregs/staff/sr1 022/r30 the NRC may not conduct or sponsor, and a person is not required to respond to, the information collection.
- 3. PAGE Point Beach Nuclear Plant Unit 1 05000266 1 of 3
- 4. TITLE Control Room Barrier Inadvertently Disabled
- 5. EVENT DATE
- 6. LER NUMBER
- 7. REPORT DATE
- 8. OTHER FACILITIES INVOLVED SEQUENTIAL REV FACILITY NAME DOCKET NUMBER MONTH DAY YEAR YEAR MONTH DAY YEAR Point Beach Nuclear Plant Unit 2 NUMBER NO.
05000301 09 18 2017 2017 001 00 11 16 2017 FACILITY NAME DOCKET NUMBER NA NA
- 9. OPERATING MODE
- 11. THIS REPORT IS SUBMrTTED PURSUANT TO THE REQUIREMENTS OF 10 CFR §: Check all that apply)
MODE1 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 20.22o1 (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 50.73(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)
~ 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)
Unit 1 I Unit 2 D 20.2203(a)(2)(iv)
D 50.46(a)(3)(ii)
D 50.73(a)(2)(v)(C)
D 73.77(a)(1) 98% I 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)
D 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 NRC Form 366A
- 12. LICENSEE CONTACT FOR THIS LER LICENSEE CONTACT r ELEPHONE NUMBER (Include Area Code)
Thomas P. Schneider, Senior Licensing Engineer 920-755-7797
- 13. COMPLETE ONE UNE FOR EACH COMPONENT FAILURE DESCRIBED IN THIS REPORT
CAUSE
SYSTEM COMPONENT MANU-REPORTABLE
CAUSE
SYSTEM COMPONENT MANU-REPORTABLE FACTURER TO EPIX FACTURER TO EPIX X
NA NA NA y
NA NA NA NA NA
- 14. SUPPLEMENTAL REPORT EXPECTED
- 15. EXPECTED MONTH DAY YEAR D YES (If yes, complete 15. EXPECTED SUBMISSION DATE)
~NO SUBMISSION DATE NA NA NA
!ABSTRACT (Limit to 1400 spaces, i.e., approximately 15 single-spaced typewritten lines)
At 1724 [COT] on 9118117 Door-061, South Control Room Door (DR) was inadvertently disabled. The door became wedged open against its backstop during control room ventilation testing. Door-061 is a barrier that functions to maintain the control room envelope (NA). The barrier was subsequently disengaged from the backstop allowing it to close. The door was inspected and returned to operable status at 1750 [COT]. While the door was stuck open, the control room was in an unanalyzed condition, a condition that could have prevented fulfillment of a safety function, and a common cause inoperability of independent trains or channels.
This event is being reported pursuant to 10 CFR 50. 73(a)(2)(ii)(B), 10 CFR 50. 73(a)(2)(v)(A),
10 CFR 50. 73(a)(2)(v)(D), and 10 CFR 50. 73(a)(2)(vii) for a degraded barrier that affected the control room envelope.
NRC FORM 366 (04-201 7)
Description of the Event:
YEAR 2017
- 3. LER NUMBER SEQUENTIAL NUMBER 001 REV NO.
00 At 1724 [COT] on 9/18/17 Door-061, South Control Room Door was inadvertently disabled. Door-061 is a barrier that functions to maintain the control room envelope during design basis accidents, events, and conditions (Safe Shutdown I High Energy Line Break I Fire I Flood). The barrier became wedged open against its backstop during control room ventilation testing. The barrier was subsequently disengaged from the backstop allowing it to close.
The door was inspected and returned to operable status at 1750 [COT]. While the door was stuck open, the control room was in an unanalyzed condition, a condition that could have prevented fulfillment of a safety function, and a common cause inoperability of independent trains or channels.
This event is being reported pursuant to 10 CFR 50.73(a)(2)(ii)(B), 10 CFR 50.73(a)(2)(v)(A),
10 CFR 50.73(a)(2)(v)(D), and 10 CFR 50.73(a)(2)(vii) for a degraded barrier that affected the control room envelope.
This 60 day licensee event report is being submitted in accordance with the following requirements; 10 CFR 50. 73(a)(2)(ii)(B), any event or condition that results in the condition of the nuclear power plant being in an unanalyzed condition; 10 CFR 50. 73(a)(2)(v)(A) and 10 CFR 50. 73(a)(2)(v)(D), any event or condition that could have prevented fulfillment of a safety function of structures or systems needed to shut down the reactor and maintain it in a safe shutdown condition or mitigate the consequences of an accident; 10 CFR 50.73(a)(2)(vii), any event where a single cause or condition caused at least one independent train or channel to become inoperable in multiple systems or two independent trains or channels to become inoperable in a single system; Where, the functions supported by the disabled barrier could not be found acceptable under all design basis accidents, events or conditions.
Cause of the Event
The cause of the inadvertent degraded barrier was a less than adequate door stop design to control the barrier during ingress/egress activities of the control room envelope with a simultaneous differential pressure transient of the control room ventilation during testing.
Analysis of the Event
Technical Specifications permit intermittent opening of the control room envelope boundaries under administrative controls. While the barrier was disabled, the boundary was unable to be rapidly closed. An engineering evaluation of the inadvertently disabled barrier determined the functions supported by the barrier could not be found acceptable under all design basis accidents, events and conditions. The less than adequate door stop design led to inadequate administrative control of the barrier during ingress/egress activities of the control room envelop with the simultaneous differential pressure transient of the control room ventilation during testing. The disabled barrier was promptly enabled, restoring the control room envelope support function.
Corrective Actions
The disabled barrier was promptly enabled, restoring the control room envelope support function, and the door stop was modified with a more robust design. Additionally, an extent of condition review was completed and Page 2 of 3 (04-2017)
U.S. NUCLEAR REGULATORY COMMISSION APPROVED BY OMB: NO. 3150-0104 EXPIRES: 3/31/2020
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LICENSEE EVENT REPORT (LER)
CONTINUATION SHEET (See NUREG-1 022, R.3 for instruction and guidance for completing this form http:/lwww.nrc.gov/reading-rm/doc-collections/nuregs/staff/sr1 022/r30
, the NRC may not conduct or sponsor, and a person is not required to respond to, the information collection.
- 3. LER NUMBER Point Beach Nuclear Plant Unit 1 05000266 corrective actions initiated for other doors with susceptible conditions.
Safety Significance
YEAR 2017 SEQUENTIAL NUMBER 001 The event was determined to be of very low safety significance. The probability of an event occurring during the short time period is very low. While the condition was present, there was no loss of any safety systems, structures or components needed to shut down the reactor, maintain safe shutdown conditions, remove residual heat, control the release of radioactive material or mitigate the consequences of an accident. There was no impact on the health and safety of the public as a result of this condition.
Similar Events
There have not been similar events of this condition in the past three years.
Component Failure Data
None Page 3 of 3 REV NO.
00