05000293/LER-1917-011, Regarding Simultaneously Opened Reactor Building Airlock Doors Caused Loss of Secondary Containment
| ML17234A318 | |
| Person / Time | |
|---|---|
| Site: | Pilgrim |
| Issue date: | 08/15/2017 |
| From: | Perkins E Entergy Nuclear Operations |
| To: | Document Control Desk, Office of Nuclear Reactor Regulation |
| References | |
| 2.17.057 LER 17-011-00 | |
| Download: ML17234A318 (6) | |
| 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)(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) |
| 2931917011R00 - NRC Website | |
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~Entergx August 15, 2017 U.S. Nuclear Regulatory Commission Attn: Document Control Desk Washington, D.C. 20555-0001 Entergy Nuclear Operations, Inc.
Pilgrim Nuclear Power Station 600 Rocky Hill Road Plymouth, MA 02360
SUBJECT:
Licensee Event Report 2017-011- 00, Simultaneously Opened Reactor Building Airlock Doors Caused Loss of Secondary Containment Pilgrim Nuclear Power Station Docket No. 50-293 Renewed License No. DPR-35 LETTER NUMBER:
2.17.057
Dear Sir or Madam:
The enclosed Licensee Event Report 2017-011-00, Simultaneously Opened Reactor Building Airlock Doors Caused Loss of Secondary Containment, is submitted in accordance with Title 10 Code of Federal Regulations 50.73.
If you have any questions or require additional information, please contact me at (508) 830-8323.
There are no regulatory commitments contained in this letter.
Sincerely, Everett~~~~~
Manager, Regulatory Assurance EPP/sc
- Attachment:
Licensee Event Report 2017-011-00, Simultaneously Opened Reactor Building Airlock Doors Caused Loss of Secondary Containment (3 Pages)
Entergy Nuclear Operations, Inc.
Pilgrim Nuclear Power Station cc:
Mr. Daniel H. Dorman Regional Administrator, Region I U.S. Nuclear Regulatory Commission 2100 Renaissance Blvd., Suite 100 King of Prussia, PA 19406-2713 Mr. John Lamb, Senior Project Manager Office of Nuclear Reactor Regulation U.S. Nuclear Regulatory Commission Mail Stop 0-8C2A Washington, DC 20555 USNRC Senior Resident Inspector Pilgrim Nuclear Power Station Letter No. 2.17.057 Page2 of 2
Attachment Letter Number 2.17.057 Licensee Event Report 2017-011-00 Simultaneously Opened Reactor Building Airlock Doors Caused Loss of Secondary Containment (3 Pages)
NRC FORM 366 U.S. NUCLEAR REGULATORY COMMISSION APPROVED BY OMB: NO. 3150-0104 EXPIRES: 03/31/2020 (04-2017) h!!Q://www.nrc.gov/reading-rm/doc-collections/nur~s/staff/sr1022/r3D the NRC may not conduct or sponsor, and a person is not required to respond to, the information collection.
- 1. FACILITY NAME
~. DOCKET NUMBER
.PAGE Pilgrim Nuclear Power Station 05000-293 1 OF3
/i. TITLE Simultaneously Opened Reactor Building Airlock Doors Caused Loss of Secondary Containment
- 5. EVENT DATE
- 6. LER NUMBER
- 7. REPORT DATE
- 8. OTHER FACILITIES INVOLVED SEQUENTIAL FACILITY NAME DOCKET NUMBER MONTH DAY YEAR YEAR REV MONTH DAY YEAR N/A NUMBER NO.
N/A 06 20 2017 2017
- - 011 00 08 15 2017 FACILITY NAME DOCKET NUMBER N/A N/A
- 9. OPERATING MODE
- 11. THIS REPORT IS SUBMITTED PURSUANT TO THE REQUIREMENTS OF 10 CFR §: Check all that apply)
N 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)
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)
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) 100 D 20.2203(a)(2)(iv)
D so.46(a)(3)(ii)
~ 50.73(a)(2)(v)(C)
D 73.77(a)(1)
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)
D 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) 00THER Specify in Abstract below or in NRG Form 366A
- 12. LICENSEE CONTACT FOR THIS LER LICENSEE CONTACT r1LEPHONE NUMBER {Include Area Code)
IMr. Everett P. Perkins, Jr.- Regulatory Assurance Manager 1508-830-8323 CAUSE SYSTEM COMPONENT MANU-REPORTABLE
CAUSE
SYSTEM COMPONENT MANU-REPORTABLE FACTURER TOEPIX FACTURER TOEPIX B
NG DR N/A y
- 14. SUPPLEMENTAL REPORT EXPECTED
- 15. EXPECTED MONTH DAY YEAR D YES (If yes, complete 15. EXPECTED SUBMISSION DATE)
[8J NO SUBMISSION DATE
~BSTRACT (Limit to 1400 spaces, i.e., approximately 15 single-spaced typewritten lines)
On June 20, 2017, at 1444 hours0.0167 days <br />0.401 hours <br />0.00239 weeks <br />5.49442e-4 months <br /> [EDT], with the reactor at 100% core thermal power and steady state conditions, plant personnel ~otified the Main Control Room that both doors in the secondary containment airlock at the 23 foot elevation on the East Side Reactor Building (RB) Entrance were opened simultaneously.
The failure of this interlock (to prevent both doors from being opened) caused a loss of secondary containment per Tec~nical Specification (TS) 3.7.C.1. The doors were immediately closed, and the secondary containment boundary was reestablished.
An 8-hour non-emergency notification was made in accordance with 10 CFR 50.72(b)(3)(v)(C), any event or condition that at the time discovery could have prevented the fulfillment of the safety function of structures or systems that are needed to control the release of radioactive material. The safety significance of this event was minimal given the impact on the secondary containment.
Secondary containment remained available and functional during the event since secondary containment was immediately restored by closing the doors.
'"'~ ~'""'.ooo (U4-£u 1 r / U.S. NUCLEAR REGULATORY COMMISSION APPROVED BY OMB: NO. 3150-0104 EXPIRES: 3/31/2020 (04-2017)
LICENSEE EVENT REPORT (LER)
CONTINUATION SHEET (See NUREG-1022, R.3 for instruction and guidance for completing this form htto://www.nrc.gov/readinq-rm/doc-collections/nureqs/staff/sr1022/r3{)
, the NRC may not conduct or sponsor, and a person is not required to respond to, the information collection.
- 3. LER NUMBER Pilgrim Nuclear Power Station 05000-293 YEAR 2017 BACKGROUND SEQUENTIAL NUMBER
- - 011 REV NO.
- - 00 The secondary containment is. designed to minimize any ground level release of radioactive materials that might result from a serious accident. The reactor building provides secondary containment during reactor gperation, when the drywell is sealed and in service. Because the secondary containment is an integral part of the complete containment system, secondary containment is required at all times that primary containment is required as well as during movement of recently irradiated fuel and during operations with the potential to drain
~he reactor vessel.
EVENT DESCRIPTION
On June 20, 2017, at 1444 [EDT] plant personnel notified the Main Control Room that both doors in the secondary containment airlock at the 23 foot elevation on the East Side Reactor Building (RB) Entrance were opened simultaneously. They noted that when they exited through Door 58 that Door 85 opened momentarily and then closed within seconds but did not latch. The failure of this interlock caused a loss of secondary containment per Techniqal Specification (TS) 3.7.C.1. The doors were immediately reclosed, and the secondary containment boundary was reestablished. A repeat of the event, which was considered testing of the airlock, rwas performed a short time later to verify and confirm the condition. Although it was verified that both doors did open, Operators could not get the door to repeat the condition upon arrival.
CAUSE OF THE EVENT
The direct cause of the event was that the Door 85 latch did not engage to keep the door from opening when the other door in the airlock (Door 58) was opened. The closer magnets did engage for the interlock to show that the door was Closed and' allow entry through the opposite door.
CORRECTIVE ACTIONS
The Door 85 closer was adjusted to add additional tension to ensure it latched without manual action.
SAFETY CONSEQUENCES
rrhe secondary containment performs no active function; however, its leak tightness is required to ensure that
~he release of radioactive materials from primary containment is restricted to those leakage paths and associated leakage rates assumed in the accident analysis and that fission products entrapped within the secondary containment structure will be treated by the Standby Gas Treatment System (SGTS) prior to discharge to the environment. Page 2 of3 (04-2017) u.s_ NUCLEAR REGULATORY COMMISSION APPROVED BY OMB: NO-3150-0104 EXPIRES: 3/31/2020 LICENSEE EVENT REPORT (LER)
CONTINUATION SHEET (See NUREG-1022, R.3 for instruction and guidance for completing this form http://www.nrc.gov/reading-rm/doc-collections/nureqs/staff/sr1022/r3[)
, the NRC may not conduct or sponsor, and a person is not required to respond to, the information collection.
- 3. LER NUMBER YEAR Pilgrim Nuclear Power Station 05000-293 2017 SEQUENTIAL NUMBER
- - 011 REV NO.
- - 00 Secondary containment remained available and functional during the event since the secondary containment interlock was immediately restored by closing the doors.
The engineering evaluation that was performed concluded that this event did not constitute a Safety System Functional Failure. (Reference NEI 99-02, Revision 7, Regulatory Assessment Performance Indicator Guideline, Section 2.2, Mitigating Systems Cornerstone, Safety System Functional Failures, Clarifying Notes, Engineering Analyses.) As such, this event will not be reported in the NRC Performance Indicator for Safety System Functional Failures since an engineering evaluation was performed which determined that the system was capable of performing its safety function during this event when both doors of the secondary containment interlock were momentarily opened simultaneously.
There are no consequences, to the general safety of the public, riuclear safety, industrial safety or radiological safety from this event.
No actions to reduce the frequency or consequence are necessary.
REPORTABILITY
Given the impact on the secondary containment, this report is submitted in accordance with the requirements of 10 CFR 50. 73 (a)(2)(v)(C), any event or condition that could have prevented the fulfillment of the safety function of structures or systems that are needed to control the release of radioactive material.
PREVIOUS EVENTS A review of LERs for the past five years did not identify any additional submittals of Secondary Containment being declared inoperable due to simultaneous opening of airlock doors.
REFERENCES CR-PNP-2017-06380 Page 3 of3