ML14183B706
| ML14183B706 | |
| Person / Time | |
|---|---|
| Site: | McGuire, Mcguire  |
| Issue date: | 07/02/2014 |
| From: | Ed Miller Division of Operating Reactor Licensing |
| To: | Murphy G Duke Energy Corp |
| References | |
| Download: ML14183B706 (5) | |
Text
1 NRR-PMDAPEm Resource From:
Miller, Ed Sent:
Wednesday, July 02, 2014 3:19 PM To:
'Murphy, George M (George.Murphy2@duke-energy.com)'
Cc:
'Bryant, Julius W (Julius.Bryant@duke-energy.com)'; 'Robertson, Jeffrey N (Jeffrey.Robertson@duke-energy.com)'
Subject:
Draft RAI for AFW Swapover LAR Attachments:
Draft I&C RAI_2nd Set.docx
- George, The NRC staffs draft RAI for the subject relief request is attached to this e-mail. The draft RAI is not an official NRC staff request and is being provided to you to facilitate a subsequent conference call to determine: 1) If the questions clearly convey the NRC staff information needs; 2) Whether the regulatory basis for the questions is understood; 3) Whether the information is already available in existing, docketed, correspondence; and 4) To determine an appropriate response time-frame. After youve had a chance to review the draft information request, please contact me to schedule the conference call.
Ed Miller (301) 415-2481
Hearing Identifier:
NRR_PMDA Email Number:
1412 Mail Envelope Properties (9C2386A0C0BC584684916F7A0482B6CAFD30068928)
Subject:
Draft RAI for AFW Swapover LAR Sent Date:
7/2/2014 3:18:38 PM Received Date:
7/2/2014 3:18:00 PM From:
Miller, Ed Created By:
Ed.Miller@nrc.gov Recipients:
"'Bryant, Julius W (Julius.Bryant@duke-energy.com)'" <Julius.Bryant@duke-energy.com>
Tracking Status: None
"'Robertson, Jeffrey N (Jeffrey.Robertson@duke-energy.com)'" <Jeffrey.Robertson@duke-energy.com>
Tracking Status: None
"'Murphy, George M (George.Murphy2@duke-energy.com)'" <George.Murphy2@duke-energy.com>
Tracking Status: None Post Office:
HQCLSTR02.nrc.gov Files Size Date & Time MESSAGE 673 7/2/2014 3:18:00 PM Draft I&C RAI_2nd Set.docx 31370 Options Priority:
Standard Return Notification:
No Reply Requested:
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Recipients Received:
DRAFT REQUEST FOR ADDITIONAL INFORMATION MCGUIRE NUCLEAR STATION, UNITS 1 AND 2 PROPOSED CHANGES TO TECHNICAL SPECIFICATION 3.3.2 IN SUPPORT OF COMPLIANCE WITH NRC ORDER EA-12-049 DOCKET NOS. 50-369 AND 50-370 By letter dated September 12, 2013, (Agencywide Documents Access and Management System (ADAMS) Accession No. ML13262A500), Duke Energy Carolinas (Duke) submitted a license amendment request (LAR) to amend the Technical Specifications (TS) 3.3.2, Engineered Safety Feature Actuation System (ESFAS) Instrumentation, FUNCTION 6.f, Auxiliary Feedwater Pump Suction Transfer on Suction Pressure - Low (c) for McGuire Nuclear Station, Units 1 and 2, in support of plant modifications required to achieve compliance with the NRC Order EA-12-049, Order Modifying Licenses with Regard to Requirements of Mitigation Strategies for Beyond-Design-Basis External Events, dated March 12, 2012. By letter dated April 9, 2014 (ADAMS Accession No. ML14097A118), the U.S. Nuclear Regulatory Commission (NRC) staff issued a request for additional information (RAI) to Duke. On May 20, 2014 (ADAMS Accession No. ML14161A231), Duke provided a response to the RAI.
Additionally, and to support the NRC staff review of the LAR, Duke made supporting documentation for this LAR available via an online reference portal. The purpose of the online reference portal was to allow the NRC staff limited access to the supporting documentation to identify those documents, or portions thereof, that need to be docketed to support the NRC staffs evaluation of the LAR. Upon review of the LAR, the April 9, 2014, response, and the online reference portal, the NRC staff has identified the following informational needs:
- 1. Please provide Calculation MCC-1210.04-00-0043
- 2. In addition to providing the calculation, please clarify the following:
- a. Calculation MCC-1210.04-00-0043 states (see Calc. Attachment 6, page No. 8 of 11) on PDF page 61 of 64 that both the Reference Accuracy (A) and Calibration Tolerance (CTE) is 1.0% of span (0.15 psig) with press (pressure) switch adjustable range from 1 to 16 psig. On the following page, page 61 of 64 the As-Left Tolerance (ALT) is specified as 1.03%
span (0.16 psig) for TSTF-493 AF & AL Tolerances for Technical Specifications Pressure Switches.
- i. Please explain why the ALT specified in PDF page 61 of 64 is not implemented in the calibration procedure (as described in the paragraph quoted below).
PDF pages 14 & 15 of 64 (Calc. page Nos. 7 & 8) of the document state:
SRA - Sensor Reference Accuracy -
Random, Independent term. The vendor states the reference accuracy as +1% of the maximum span (Reference J). However, the as-left setting band in the calibration procedure is + 0.3 psig or
+ 2.67% of calibrated span. Since the methodology of calibrating verifies all attributes of the reference accuracy (Assumption G),
the larger value for the calibration tolerance may be substituted for reference accuracy as opposed to inclusion of the calibration tolerance as a separate term (Reference I). The calibration tolerance (as-left setting band) is simply the term used to represent reference accuracy and does not represent a separate uncertainty term.
= + 2.67% of calibration span.
ii. How was the +2.67% value determined?
iii. Please provide justifications how the as-left setting band in the calibration procedure of + 2.67% of calibration span will ensure the early detection of instrument channel degradation, compared to reference accuracy band of + 1% provided by the vendor, and calculated by the licensee.
iv. Please explain how the calculated ALT (see PDF page 62 of 64) is used.
- v. Please explain how the calculated AFT (see PDF page 62 of 64) is used.
- b. PDF page 15 of 64 (Calc. Page No. 8) states:
SD -Sensor Drift -
A drift study (Attachment 5) has been performed on the safety related pressure switches in the CA/RN suction pressure function at McGuireThis was performed to show that the drift values provided by the vendor is acceptable to the McGuire actual in-use experience. A 95/95 confidence interval was applied and showed that +2.67% of calibrated span is conservative relative to actual experience
= + 2.67% of calibration span.
PDF page 16 of 64 (Calc. Page No. 9) shows that the 2.67% value is used to calculate the term eps. PDF page 19 of 64 (Calc. Page No. 12) shows term eps used to calculate TLA calculation. Therefore the 2.67%
value is used to determine TLA in page 18 of 64 (Calc. Page No. 12).
- i. Please provide details of the analysis performed on plant drift data including the analysis performed on outlier rejection, normality testing, linearity, and 95/95 confidence level.
ii. Please explain why the actual plant drift study data is not used in selection of the sensor drift band.
- c. PDF page 61 of 64 (Calc. Attachment 6, page 8 of 11) states drift (D) as 3.42% of span. This 3.42% drift value is used in the AFT calculation. PDF page 62 of 64 (Calc. Attachment 6, page 9 of 11) states sensor drift (SD) as 2.67% of span. This drift value is used in TLA calculation in PDF page 15 of 64 (Calc. page 8 of 16) for TLA calculation.
- i. Please explain why sensor drift value of 3.42% is used in AFT calculation and a drift value of 2.67% is used in TLA calculation.
ii. The drift value used for in the AFT is larger than the drift value used in the TLA; therefore the AFT value does not confirm that the drift value used in the TLU calculation is still valid, as it should.
Please explain.
iii. It is assumed that the item referred to as TLA in the body of the calculation is referred to as TLU in Attachment 6. Correct?