05000334/LER-2019-001, Low Head Safety Injection Discharge Relief Valve Did Not Reseat During Surveillance Test
| ML20003D859 | |
| Person / Time | |
|---|---|
| Site: | Beaver Valley |
| Issue date: | 12/30/2019 |
| From: | Penfield R FirstEnergy Nuclear Operating Co |
| To: | Document Control Desk, Office of Nuclear Reactor Regulation |
| References | |
| L-19-294 LER 2019-001-00 | |
| Download: ML20003D859 (6) | |
| Event date: | |
|---|---|
| Report date: | |
| Reporting criterion: | 10 CFR 50.73(a)(2)(ii)(B), Unanalyzed Condition 10 CFR 50.73(a)(2)(v)(B), Loss of Safety Function - Remove Residual Heat 10 CFR 50.73(a)(2)(x) 10 CFR 50.73(a)(2)(v), Loss of Safety Function 10 CFR 50.73(a)(2)(i)(B), Prohibited by Technical Specifications 10 CFR 50.73(a)(2)(i) |
| 3342019001R00 - NRC Website | |
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FirstEnergy Nuclear Operating Company Rod L. Penfield Site Vice President December 30, 2019 L-19-294 ATIN: Document Control Desk U. S. Nuclear Regulatory Commission Washington, DC 20555-0001
SUBJECT:
Beaver Valley Power Station, Unit No. 1 Docket No. 50-334, License No. DPR-66 LER 2019-001-00 10 CFR 50.73 Beaver Valley Power Station P.O. Box4 Shippingport, PA 15077 724-682-5234 Fax: 724-643-8069 Enclosed is Licensee Event Report (LER) 2019-001-00, "Low Head Safety Injection Discharge Relief Valve Did Not Reseat During Surveillance Test". This event is being reported in accordance with 10 CFR 50.73(a)(2)(ii)(B) and 10 CFR 50.73(a)(2)(v)(B),
(C), (D).
There are no regulatory commitments contained in this submittal. Any actions discussed in this document that represent intended or planned actions are described for the NRC's information, and are not regulatory commitments.
If there are any questions or if additional information is required, please contact Mr. Steve Sawtschenko, Manager, Regulatory Compliance and Emergency Response, at 724-682-4284.
~*.*1v Rod L. Penfiel~
Site Vice President Enclosure - Beaver Valley Power Station, Unit 1 LER 2019-001-00 cc:
Mr. D. C. Lew, NRC Region I Administrator Mr. J. A Krafty, NRC Senior Resident Inspector Ms. J.C. Tobin, NRC Project Manager INPO Records Center (via INPO Industry Reporting and Information System)
Mr. L. Winker (BRP/DEP)
Enclosure L-19-294 Beaver Valley Power Station, Unit 1 LER 2019-001-00
NRC FORM 366 U.S. NUCLEAR REGULATORY COMMISSION APPROVED BY 0MB: NO. 3150-0104 EXPIRES: 03/31/2020 (04-2018)
, the NRC may not conduct or sponsor, and a person is not required to "ll-:it**""'\\\\:
respond to, the information collection.
3.Page Beaver Valley Power Station, Unit 1 05000 334 1
OF 4
- 4. Title Low Head Safety Injection Discharge Relief Valve Did Not Reseat During Surveillance Test
- 5. Event Date
- 6. LER Number
- 7. Report Date
- 8. Other Facilities Involved I
Sequential I Rev Month Facility Name Docket Number Month Day Year Year Number No.
Day Year N/A 05000 Facility Name Docket Number 11 2
2019 2019.
001 00 12 30 2019 N/A 05000
- 9. Operating Mode
- 11. This Report is Submitted Pursuant to the Requirements of 1 O 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)
D 20.2201{d)
D 20.2203{a)(3)(ii) w 50.73(a)(2)(ii)(B)
D 50. 73(a){2)(viii){B) 3 D
D D
D 20.2203{a){1) 20.2203{a)(4) 50.73(a){2)(iii)
- 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) w 50.73(a)(2)(v)(B)
D 73. 71 (a)(5)
D 20.2203(a)(2)(iv)
D 50.46(a){3)(ii) w 50.73(a)(2)(v)(C)
D 73.77(a)(1) 0 D 20.2203(a)(2)(v)
D 50.73(a){2)(i)(A) w 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)
D Other (Specify in Abstract below or in
CAUSE OF EVENT
SEQUENTIAL NUMBER 001 REV NO.
1-G The direct causes were identified as Low Head Safety Injection (LHSI) relief valves have a set pressure below the high-peak LHSI pump start pressure pulse and RV-1Sl-845A did not reseat when system pressure dropped below the expected design blowdown pressure. This was because station personnel did not implement the actions intended to ensure that the guide ring settings for spare Crosby relief valve S/N 54679 were verified, validated, and corrected, prior to installation into the LHSI system. Specifically, the corrective action that was intended to verify the settings for SIN 54679 was ultimately closed to generic process guidance versus discrete action, resulting in the valve being installed at the RV-1 Sl-845A location during 1 R26 with its guide ring likely improperly set.
Since RV-1Sl-845A did not reseat until 'A' LHSI pump was secured, the blowdown adjustment ring setting was most likely not set correctly. In addition, the LHSI system dynamics and associated pressure surges have not been adequately bounded to address and preclude relief valves momentarily lifting when LHSI pumps are started for routine testing or plant evolutions. As a result, the relief valves on the discharge header of the LHSI system are called upon to lift and reseat on a more frequent basis than intended, creating opportunities for a valve to fail to reseat and potentially damaging internal valve components over time due to repeated cycling. Two additional instrumented runs of the 'A' LHSI pump were performed while recording pressures measured upstream and downstream of the currently isolated RV-1 Sl-845A. Upon pump start, a momentary pressure pulse above the lift setpoint of the relief valves was noted upstream of RV-1 Sl-845A, and both RV-1 Sl-845B and RV-1 Sl-845C were visually observed to lift and reseat. This was the first test of the LHSI discharge header relief valves in which a pressure spike in excess of the relief valve setpoints was observed, and the first in which the valves were physically observed to lift.
ANALYSIS OF EVENT
The plant risk associated with the BVPS Unit 1 relief valve RV-1 Sl-845A leakage on November 2, 2019, during performancE of surveillance test 1 OST-11.1, "Safety Injection Pump Test," is considered to be very low. This is based on meeting the surveillance test pump flow acceptance criteria for the 'A' LHSI pump, which assures that the pump will satisfy its design intent to deliver sufficient flow upon safety injection recirculation. It is therefore concluded that there is reasonable assurance that the leakage was small enough such that there would not be a loss of the safety injection recirculation safety function or significant impact on the BVPS Unit 1 Emergency Core Cooling System (ECCS) to mitigate core damage.
Additionally, the ECCS leakage that bypasses containment would not lead to any large early release.
Engineering evaluation concluded that the projected dose would exceed the 10 CFR 50.67 Exclusion Area Boundary dose limit, and the 10 CFR 50 General Design Criteria (GDC) 19 for control room dose limit.
Based on the above, the safety significance of the relief valve RV-1 Sl-845A leakage event that occurred on November 2, 2019 was very low. This event is reportable per 10 CFR 50. 73(a)(2)(ii)(B) and 10 CFR 50. 73(a)(2)(v)(B), (C), (D) as an Unanalyzed Condition and a condition that could have prevented the Fulfillment of a Safety Function as reported by Event Notification54366 on November 2, 2019 at 2303 hours0.0267 days <br />0.64 hours <br />0.00381 weeks <br />8.762915e-4 months <br />.
CORRECTIVE ACTIONS
- 1.
The 'A' LHSI discharge relief valve, RV-1 Sl-845A, was isolated, and a temporary gag was installed through the temporary modification process. (Complete November 02, 2019)
I
- 2.
The 'A' LHSI discharge relief valve, RV-1 Sl-845A, will be removed during the next refueling outage and tested to verify the blowdown ring setting.
- 3.
All the Crosby model JRAK relief valves with undocumented blowdown ring settings wiil be sent out to a qualified vendor for refurbishment, testing and reset of the rings to achieve a blowdown of 10% below the setpoint value.
Validate and document the final blowdown ring settings from vendor report.
Completion of items 2 and 3 listed above are being tracked in the Corrective Action Program.
PREVIOUS SIMILAR EVENTS
A review of previous similar incidents found the following:
BVPS Unit 1 LER 2010-003-00, "Premature Lifting of ECCS Relief Valve Results in Post-Accident Outside-Containment Leakage Limits to Be Exceeded" (CR-10-85863). The existing discharge piping of RV-1Sl-845B placed an adverse force on the relief valve (i.e., nozzle loading) due to inadequate piping support and/or incorrect piping alignment. This nozzle loading resulted in the relief valve lifting at a lower pressure than its set pressure (235 psig) in its installed location. This relief valve showed an acceptable lift pressure setpoint during bench testing prior to its installation in November 2010:
Corrective actions were to repair the existing discharge piping configuration for valve RV-1 Sl-8458 and correct possible misconfiguration of the discharge piping for sister valves RV-1 Sl-845A/C.
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