05000298/LER-2018-003, Safety Valve Failure Results in Loss of Safety Function
| ML18353A279 | |
| Person / Time | |
|---|---|
| Site: | Cooper  |
| Issue date: | 12/10/2018 |
| From: | Dent J Nebraska Public Power District (NPPD) |
| To: | Document Control Desk, Office of Nuclear Reactor Regulation |
| References | |
| NLS2018067 LER 2018-003-00 | |
| Download: ML18353A279 (4) | |
| Event date: | |
|---|---|
| Report date: | |
| Reporting criterion: | 10 CFR 50.73(a)(2)(ii)(A), Seriously Degraded 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)(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) 10 CFR 50.73(a)(2)(vii), Common Cause Inoperability 10 CFR 50.73(a)(2)(i) |
| 2982018003R00 - NRC Website | |
text
H Nebraska Public Power District Alwa1s there when 1ou need us NLS2018067 December 10, 2018 U.S. Nuclear Regulatory Commission Attention: Document Control Desk Washington, D.C. 20555-0001
Subject:
Licensee Event Report No. 2018-003-00 Cooper Nuclear Station, Docket No. 50-298, DPR-46
Dear Sir or Madam:
The purpose of this correspondence is to forward Licensee Event Report 2018-003-00.
There are no new commitments contained in this letter.
Sincerely,
~~a Vice President Nuclear-Chief Nuclear Officer
/jo Attachment: Licensee Event Report 2018-003-00 cc: Regional Administrator w/attachment USNRC - Region IV Cooper Project Manager w/attachment USNRC - NRR Plant Licensing Branch IV Senior Resident Inspector w/attachment USNRC-CNS SRAB Administrator w/attachment COOPER NUCLEAR STATION NPG Distribution w/attachment INPO Records Center w/attachment via ICES entry SORC Chairman w/attachment CNS Records w/attachment P.O. Box 98 / Brownville, NE 68327-0098 Telephone: (402) 825-3817 / Fax: (402) 825-5217 www.nppd.com
NRCFORM 366 U.S. NUCLEAR REGULATORY COMMISSION APPROVED BY 0MB: NO. 3150-0104 EXPIRES: 03/31/2020 (04-2018)
Esfimated, the NRG may not conduct or sponsor, and a oerson is not reouired ta resoond to the inforrnafion collecfion.
- 1. Facility Name
- 12. Docket Number
. Page Cooper Nuclear Station 05000298 1 of 3
- 4. Title Safety Valve Failure Results in Loss of Safety Function
- 5. Event Date
- 6. LER Number
- 7. Report Date
- 8. Other Facilities Involved Sequenfial Rev Facility Name Docket Number Month Day Year Year Number No.
Month Day Year 05000 10 10 2018 2018 - 003
- - 00 12 10 2018 Facility Name Docket Number 05000
- 9. Operating Mode
- 11. This Report is Submitted Pursuant to the Requirements of 10 CFR §: (Check all that apolv) 0 20.2201(b)
D 20.2203(a)(3)(i) 0 50.73(a)(2)(ii)(A) 0 50. 73(a)(2)(viii)(A) 5 0 20.2201(d) 0 20.2203(a)(3)(ii) 0 50.73(a)(2)(ii)(B) 0 50.73(a)(2)(viii)(B) 0 20.2203(a)(1)
D 20.2203(a)(4) 0 50.73(a)(2)(iii) 0 50.73(a)(2)(ix)(A) 0 20.2203(a)(2)(i)
D 50.36(c)(1)(i)(A) 0 50. 73(a)(2)(iv)(A) 0 50.73(a)(2)(x)
- 10. Power Level 0 20.2203(a)(2)(ii)
D 50.36(c)(1)(ii)(A) 0 50.73(a)(2)(v)(A)
D 73.71(a)(4) 0 20.2203(a)(2)(iii)
O 50.36(c)(2) 0 50.73(a)(2)(v)(B) 0 73.71(a)(5) 0 20.2203(a)(2)(iv)
D 50.46(a)(3)(ii) 0 50.73(a)(2)(v)(C) 0 73.77(a)(1) 000 0 20.2203(a)(2)(v)
D 50.73(a)(2)(i)(A) 1:8:1 50. 73(a)(2)(v)(D) 0 73.77(a)(2)(i)
D 20.2203(a)(2)(vi)
D 50.73(a)(2)0)(B) 0 50.73(a)(2)(vii) 0 73.77(a)(2)(ii)
D 50.73(a)(2)(i)(C) 0 Other (Specify in Abstract below or in =
PLANT STATUS YEAR 2018 SEQUENTIAL NUMBER
- - 003 Cooper Nuclear Station (CNS) was in Mode 5, Refueling, at O percent power, at the time of the event.
BACKGROUND REV NO.
- - 00 The pressure relief system includes three American Society of Mechanical Engineers code safety valves *
(SV) [EIIS:SB] which are located on the main steam lines [EIIS:SB] within the drywell [EIIS:NH], between the reactor vessel [EIIS:RPV] and the first main steam isolation valve [EIIS:ISV]. The SVs provide protection against over pressurization of the nuclear system and discharge directly into the interior space of the drywell.
Technical Specification (TS) Limiting Condition for Operation 3.4.3 requires the safety function of three SVs to be operable. The nominal set pressure and tolerances for these valves are established in CNS TS Surveillance Requirement (SR) 3.4.3.1.
EVENT DESCRIPTION
On September 29, 2018, at 20:53, CNS commenced Refueling Outage 30 (RE30) and subsequently entered Mode 5 on October 2, 2018, at 02:41.
During RE30 activities, MS-RV-70ARV (Serial Number BL-2463) was removed from service and sent off-site for as-found setpoint pressure testing per station procedure. On October 10, 2018, the as-found testing was performed at National Technical Systems (NTS) Laboratories (formerly Wyle Laboratories).
The valve was tested three times. Per procedure, the acceptance criterion is 1202.8 psig - 1277,2 psig.
The as-found testing result for the first test was 1278.6 psig. The second and third tests were performed with the results being 1260.0 psig and 1263.2 psig, respectively.
TS Surveillance Requirement setpoint criteria for the safety valves are 1240 +/-37.2 psig.
One SV is tested every outage and all three SVs are tested every six years. In addition, TS specify that all three SVs shall be operable. The last time MS-RV-70ARV was tested was in 2012 during RE27. The result of that test was within acceptance criteria at 1255 psig.
The remaining two valves, MS-RV-70BRV and MS-RV-70CRV were also tested for as-found setpoint pressure at NTS on November 1, 2018 and October 30, 2018, respectively. Both of these valves passed the acceptance criteria.
The safety valve is currently at the testing facility awaiting completion of inspection and repair activities.
CNS will provide additional event details, the safety significance, cause(s), and corrective action(s) in a supplement to this Licensee Event Report. Page 2 of 3 (04-2018)
U.S. NUCLEAR REGULATORY COMMISSION APPROVED BY 0MB: NO. 3150-0104 EXPIRES: 3/31/2020
~l,lt{Cc.t.,
- w*..
{~)
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/nuregs/staff/sr1022/r3[)
, the NRC may not conduct or sponsor, and a person is not required to respond to, the infonmation collection.
- 1. FACILITYNAME 2 DOCKET NUMBER
- 3. LER NUMBER Cooper Nuclear Station 05000-298 BASIS FOR REPORT YEAR 2018 SEQUENTIAL NUMBER
- - 003 This event is being reported per 10 CFR 50. 73(a)(2)(v)(D) as any event or condition that could have prevented the fulfillment of the safety function of structures or systems that are needed to mitigate the consequences of an accident.
REV NO.
- - 00 Page 3 of 3