NLS2009077, Response to Request for Additional Information Regarding 10 CFR 50.55a, Request RV-06, Revision 0
| ML092800387 | |
| Person / Time | |
|---|---|
| Site: | Cooper  |
| Issue date: | 09/30/2009 |
| From: | O'Grady B Nebraska Public Power District (NPPD) |
| To: | Document Control Desk, Office of Nuclear Reactor Regulation |
| References | |
| NLS2009077, TAC ME1521 | |
| Download: ML092800387 (6) | |
Text
N Nebraska Public Power District "Always there when you need us" NLS2009077 September 30, 2009 U.S. Nuclear Regulatory Commission Attention: Document Control Desk Washington, D.C. 20555-0001
Subject:
Response to Request for Additional Information Regarding 10 CFR 50.55a Request RV-06, Revision 0 Cooper Nuclear Station, Docket No. 50-298, DPR-46
References:
- 1.
Letter from Carl F. Lyon, U.S. Nuclear Regulatory Commission, to Stewart B. Minahan, Nebraska Public Power District, dated August 26, 2009, "Cooper Nuclear Station - Request for Additional Information Re:
Relief Request No. RV-06 (TAC No. ME 1521)"
- 2.
Letter from Brian J. O'Grady, Nebraska Public Power District, to the U.S.
Nuclear Regulatory Commission, dated June 18, 2009, "10 CFR 50.55a Request Number RV-06, Revision 0"
Dear Sir or Madam:
The purpose of this letter is for the Nebraska Public Power District (NPPD) to submit a response to the Nuclear Regulatory Commission (NRC) Request for Additional Information (RAI) dated August 26, 2009 (Reference 1). The additional information requested by the RAI is in support of the NRC review of 10 CFR 50.55a request for Cooper Nuclear Station (CNS) submitted by letter
.dated June 18, 2009 (Reference 2). In that letter, NPPD requested relief from certain inservice test valve testing requirements as they pertain to check valves, solenoid operated valves, and air operated valves within the Control Rod Drive system.
The response to the RAI is provided in the attachment to this letter.
As stated in Reference 2, approval of this request is requested by June 28, 2010. Approval of this request is not needed to support future work at CNS.
COOPER NUCLEAR STATION PC. Box 98 / Brownville, NE 68321-0098 Telephone: (402) 825-3811 / Fax: (402) 825-5211 www nppd corn
NLS2009077 Page 2 of 2 Should you have any questions regarding this submittal, please contact David Van Der Kamp, Licensing Manager, at (402) 825-2904.
Sincerely, Brian J. O'Gr)ydy Site Vice President
/dm Attachment cc:
Regional Administrator w/ attachment USNRC - Region IV Cooper Project Manager w/ attachment USNRC - NRR Project Directorate IV-1 Senior Resident Inspector w/ attachment USNRC - CNS NPG Distribution w/ attachment CNS Records w/ attachment
NLS2009077 Attachment Page 1 of 3 Attachment Response to Request for Additional Information Regarding 10 CFR 50.55a Request RV-06, Revision 0 Cooper Nuclear Station, Docket No. 50-298, DPR-46 The U.S. Nuclear Regulatory Commission staff has reviewed the information provided by Nebraska Public Power District (the licensee) for Cooper Nuclear Station (CNS) in its letter dated June 18, 2009, and determined that additional information is necessary to complete the review ofReliefRequest No. RV-06. Please provide a response that addresses the following questions.
NRC Question No. 1 Request R V-06 has two separate discussions on eight valves. Neither discussion identifies which Code requirement is applicable. Please clarify by providing a discussion on how each Code requirement applies to the situation, the alternative, and the reason for the request for each component listed.
Nebraska Public Power District (NPPD) Response The following discussions clarify the applicable code requirements, the alternative, and the reason for the request for each component in RV-06.
A. CRD-CV-138CV Cooling water header check valve (typical of 137)
The applicable code requirements for this check valve is that it be exercised open and closed per ASME OMb Code-2003 Sub-section ISTC-5221 (a) at a frequency determined by ISTC-3510. The check valve is adequately opened (non-safety function) with cooling water and closed (safety function) with successful control rod motion. The alternative being requested is to test this check valve via control rod exercising in accordance with Technical Specification SR 3.1.3.2 and Surveillance Requirement (SR) 3.1.3.3. The reason for this request is that this approach is consistent with Generic Letter (GL) 89-04, Position 7, and NUREG 1482, Revision 1, Section 4.4.6.
B. CRD-SOV-SO120, S0121, S0122, S0123 insert and withdrawal solenoid valves (typical of 137)
The applicable code requirements for these solenoid valves are that they be exercised closed at the appropriate frequency per ISTC-3510, fail safe tested closed per ISTC-3560, and stroke time tested closed per ISTC-5151. The solenoid valves are adequately exercised and fail safe tested closed with successful normal control rod motion. The alternative being requested is to test these solenoid valves via control rod exercising in accordance with Technical Specification SR 3.1.3.2 and SR 3.1.3.3. The stroke time
NLS2009077 Attachment Page 2 of 3 testing per ISTC-5151 will not be performed. The reason for this request is that this approach is consistent with GL 89-04, Position 7, and NUREG 1482, Revision 1, Section 4.4.6.
C. CRD-AOV-CV126 and CRD-AOV-CV127 Scram inlet and outlet valves (typical of 137)
The applicable code requirements for these air-operated valves are that they be exercised open at the appropriate frequency per ISTC-35 10, fail safe tested open per ISTC-3560, and stroke time tested open per ISTC-5131. The air-operated valves are adequately exercised and fail safe tested open during successful scram time testing for each applicable control rod. The alternative being requested is to test these air-operated valves via control rod scram time testing in accordance with Technical Specification SR 3.1.4.1 and SR 3.1.4.2. The stroke time testing per ISTC-5130 will not be performed. The reason for this request is that this approach is consistent with GL 89-04, Position 7, and NUREG 1482, Revision 1, Section 4.4.6.
D. CRD-CV-1 14CV Scram outlet check valve (typical of 137)
The applicable code requirements for this check valve is that it be exercised open and closed per ISTC-5221(a) at a frequency determined by ISTC-3510. The check valve is adequately opened (safety function) with successful scram time testing and are not tested in the closed (non-safety function) direction. Therefore, the exercise testing in the non-safety direction per ISTC-5220 will not be performed. The alternative being requested is to test this check valve open via scram time testing in accordance with Technical Specification SR 3.1.4.1 and SR 3.1.4.2. The reason for this request is that this approach is consistent with GL 89-04, Position 7, and NUREG 1482, Revision 1, Section 4.4.6.
Another precedent in support of this approach for this check valve is an approved Xcel Energy relief request, VR-01, for the Monticello Nuclear Generating Plant.
NRC Question No. 2 CNS Updated Safety Analysis Report details that Control Rod Drive (CRD) scram outlet check valve, CRD-CV-114CV, also has a close function that prevents pressure from the Scram Discharge Volume header from operating the control rod drive mechanism. Please explain how CRD-CV-114CV close function is tested and its frequency and/or explain why CRD-CV-1 14CV close function is not tested.
NPPD Response The CRD-CV-1 14CV check valve (typical of 137) is not tested in the closed direction within the IST Program. The basis behind this position is that the closed function listed in the USAR is a design function of the system, but is not considered a safety-related function.
Flow from the CRD to the Scram Discharge Volume (open function) occurs throughout the entire scram stroke of the control rod and continues until the volume pressure equals reactor vessel pressure. Any potential demand for check valve closure would occur only after the
NLS2009077 Attachment Page 3 of 3 rod is fully inserted and latched. Therefore, failure of the scram outlet check valve to close would not prevent the system from performing its safety function since such a condition would occur only after full rod insertion and latching. In addition, testing only the open safety-related function during scram time testing is consistent with GL 89-04, Position 7, and NUREG 1482, Revision 1, Section 4.4.6. Another precedent in support' of this approach for this check valve is an approved Xcel Energy relief request, VR-01, for the Monticello Nuclear Generating Plant.
Precedents In addition to the precedents provided in Request RV-06, submitted to the NRC by NPPD letter dated June 18, 2009, Relief VR-01 for the Monticello Nuclear Generating Plant also represents a precedent. This relief was approved by the NRC on December 10, 2003 (TAC No. MB9736).
ATTACHMENT 3 LIST OF REGULATORY COMMITMENTS© 4 ATTACHMENT 3 LIST OF REGULATORY COMMITMENTS©4 Correspondence Number: NLS2009077 The following table identifies those actions committed to by Nebraska Public Power District (NPPD) in this document. Any other actions discussed in the submittal represent intended or planned actions by NPPD. They are described for information only and are not regulatory commitments. Please notify the Licensing Manager at Cooper Nuclear Station of any questions regarding this document or any associated regulatory commitments.
COMMITMENT COMMITTED DATE COMMITMENT NUMBER OR OUTAGE None N/A N/A 4-4
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