ML24334A057
| ML24334A057 | |
| Person / Time | |
|---|---|
| Site: | Prairie Island  |
| Issue date: | 12/11/2024 |
| From: | Ballard B Plant Licensing Branch III |
| To: | Northern States Power Co |
| Ballard, Brent | |
| References | |
| EPID L-2024-LLR-0067 | |
| Download: ML24334A057 (1) | |
Text
December 11, 2024 LICENSEE:
Northern States Power Company FACILITY:
Prairie Island Nuclear Generating Plant, Unit 1
SUBJECT:
SUMMARY
OF NOVEMBER 18, 2024, PUBLIC MEETING WITH NORTHERN STATES POWER COMPANY, REGARDING PROPOSED ALTERNATIVE RELIEF REQUEST-10, AUXILIARY FEEDWATER VALVE TESTING (EPID L-2024-LLR-0067)
On November 18, 2024, a public meeting via webinar was held between the U.S. Nuclear Regulatory Commission (NRC) and representatives of Northern States Power Company, a Minnesota corporation (NSPM, the licensee), doing business as Xcel Energy. The purpose of the meeting was to discuss a proposed alternative request to defer the quarterly and post-replacement testing of certain valves in the auxiliary feedwater (AFW) system until startup following the current refueling outage when plant conditions support performance of the tests at Prairie Island Nuclear Generating Plant, (Prairie Island) Unit 1.
By web-based submission dated October 14, 2024 (Agencywide Documents Access and Management System (ADAMS) Accession No. ML24288A011), NSPM submitted Proposed Alternative Request RR-10 to the NRC for review. By letter dated October 30, 2024 (ML24298A055), the NRC staff informed NSPM the proposed alternative was not required because deferment of testing until plant startup meets the applicable American Society of Mechanical Engineers (ASME) Operation and Maintenance (OM) Code requirements, as incorporated by reference in Title 10 of the Code of Federal Regulations (10 CFR), section 50.55a, Codes and Standards. The licensee requested a public meeting with the NRC staff to discuss and better understand the staffs determination. The meeting notice and agenda, dated November 7, 2024, are available in ADAMS at ML24312A361.
At the beginning of the public meeting, NSPM summarized proposed Alternative Request RR-10 for a 10 CFR 50.55a(z)(2) hardship authorization to extend the ISTC-3310 and ISTC-3570 required test interval for a turbine driven auxiliary feedwater pump (TDAFWP) main steam supply control valve (air-operated valve (AOV)), a TDAFWP recirc/lube oil cooling control valve (AOV), a TDAFWP recirc/lube oil cooling line check valve, and a motor-driven AFW pump recirc/lube oil cooling line check valve, until reaching technical specification MODE 3 during startup of Prairie Island, Unit 1, from the fall 2024 refueling outage. The licensee stated that the AFW system in Prairie Island, Unit 1, is out of service in the current plant condition, and that it is not practicable to test these valves without a steam supply in this plant condition.
During the public meeting, the NRC staff discussed the following requirements in the current Code of Record for the Prairie Island inservice testing (IST) program, which is the 2004 Edition through the 2006 Addenda of the American Society of Mechanical Engineers (ASME) Operation and Maintenance (OM) Code as incorporated by reference in 10 CFR 50.55a:
Subsection ISTC, paragraph ISTC-3520, Exercising Requirements, ISTC-3521, Category A and Category B Valves, subparagraphs (f), (g), and (h), state the following:
(f) valves full-stroke exercised at cold shutdowns shall be exercised during each cold shutdown, except as specified in ISTC-3521(g). Such exercise is not required if less than 3 months. During extended shutdowns, valves that are required to perform their intended function (see ISTA-1100) shall be exercised every 3 months, if practicable.
(g) valve exercising during cold shutdown shall commence within 48 hr [hours] of achieving cold shutdown and continue until all testing is complete or the plant is ready to return to operation at power. For extended outages, testing need not be commenced in 48 hr, provided all valves required to be tested during cold shutdown will be tested before or as part of plant startup. However, it is not the intent of this Subsection to keep the plant in cold shutdown to complete cold shutdown testing.
(h) all valve testing required to be performed during a refueling outage shall be completed before returning the plant to operation at power.
Paragraph ISTC-3522, Category C Check Valves, subparagraphs (d), (e), and (f), state the following:
(d) Valves exercised at shutdowns shall be exercised during each shutdown, except as specified in ISTC-3522(e). Such exercise is not required if the interval since the previous exercise is less than 3 months. During extended shutdowns, valves that are required to perform their intended function (see ISTA-1100) shall be exercised every 3 months, if practicable.
(e) Valve exercising shall commence within 48 hr of achieving cold shutdown and continue until all testing is complete or the plant is ready to return to operation at power. For extended outages, testing need not be commenced in 48 hr if all valves required to be tested during cold shutdown will be tested before or as part of plant start-up. However, it is not the intent of this Subsection to keep the plant in cold shutdown to complete cold shutdown testing.
(f) All valve testing required to be performed during a refueling outage shall be completed before returning the plant to operation at power.
Paragraph ISTC-3570, ISTC-3570 Valves in Systems Out of Service, states:
For a valve in a system declared inoperable or not required to be operable, the exercising test schedule need not be followed. Within 3 months before placing the system in an operable status, the valves shall be exercised and the schedule followed in accordance with requirements of this Subsection.
Based on these ASME OM Code requirements, the NRC staff discussed its determination that the NSPM is allowed by ISTC-3521 for the applicable AOVs and ISTC-3522 for the applicable check valves to test these valves as part of plant start-up because it is not practicable to test them during the extended shutdown. The staff also noted that these paragraphs emphasize that the intent of the OM Code is not to keep a plant in cold shutdown to complete testing. The NRC staff discussed ISTC-3570, which requires that the schedule in subsection ISTC be followed when preparing to return a system to service. Similarly, ISTC-3310 would normally require the one replaced valve (TDAFWP recirc/lube oil cooling line check valve) in the AFW system to be tested where practicable. The NRC staff stated that ISTC-3521 and ISTC-3522 address the situation where it is not practicable to test valves when preparing to return the system to service and allows the required testing as part of plant startup.
The NRC staff stated that its primary consideration in this instance is that it is not practicable to test the valves until plant startup is commenced. If it had been practicable to test these valves in the current plant condition, the ASME OM Code would require the licensee to test all four valves prior to plant startup or to submit an alternative request. When testing as part of plant startup, the staff expects that the licensee will determine immediately if there are any performance issues with the valves and take appropriate action to address, in accordance with applicable requirements.
A list of meeting attendees is attached. Members of the public were in attendance. Public meeting feedback forms were not received. Comments received included the following:
During the public comment portion of the meeting, Mark Gowin (ASME OM Code committee member, attending as a member of the public) noted his opinion that the NRC staff position is consistent with the guidance in NUREG-1482, Revision 3, Guidelines for Inservice Testing at Nuclear Power Plants, section 3.1.1.2, Testing at a Refueling Outage Frequency for Valves Tested During Power Ascension. Mark Gowin suggested that the language in NUREG-1482 be reviewed for additional clarification and indicated that the ASME OM Code committee may consider clarification of ISTC-3570 for similar situations.
Please direct any inquiries regarding this meeting summary to Luis Cruz Rosado at luis.cruzrosado@nrc.gov or to me at brent.ballard@nrc.gov.
Sincerely,
/RA/
Brent Ballard, Project Manager Plant Licensing Branch III Division of Operating Reactor Licensing Office of Nuclear Reactor Regulation Docket No. 50-282
Enclosure:
List of Attendees cc: Listserv
Enclosure LIST OF ATTENDEES NOVEMBER 18, 2024, PUBLIC MEETING WITH NORHTERN STATES POWER COMPANY, REGARDING PROPOSED ALTERNATIVE RELIEF REQUEST-10, AUXILIARY FEEDWATER VALVE TESTING Name Organization Stewart Bailey Nuclear Regulatory Commission (NRC)
Brent Ballard NRC Luis Cruz Rosado NRC Thomas Scarbrough NRC Dan Tesar NRC Harrison Bourgoin Northern States Power Company (NSPM)
Katherine Brandtjen NSPM James Bremer NSPM Thomas Conboy NSPM Jeff Connors NSPM Ronald Jacobson NSPM Jeffrey Kivi NSPM Ilya Leontovich NSPM Ashley Malek NSPM Michael Miller NSPM Sara Scott NSPM Bruce Sinn-Brown NSPM Bjorn Soderlund NSPM Mark Gowin Member of the Public Dharmeshkumar Patel Member of the Public Betsy Moenkedick Member of the Public
ML24334A057 NRC-001 OFFICE NRR/DORL/LPL3/PM NRR/DORL/LPL3/LA NRR/DORL/LPL3/BC(A) NRR/DORL/LPL3/PM NAME LCruzRosado SRohrer IBerrios BBallard DATE 11/26/2024 12/3/2024 12/4/2024 12/11/2024