ML092950179
| ML092950179 | |
| Person / Time | |
|---|---|
| Site: | Point Beach  |
| Issue date: | 10/22/2009 |
| From: | Justin Poole Plant Licensing Branch III |
| To: | Jim Costedio, Flentje F, Hale S Point Beach |
| Poole Justin/DORL/LPL3-1/ 301-415-2048 | |
| References | |
| Download: ML092950179 (3) | |
Text
From:
Poole, Justin Sent:
Thursday, October 22, 2009 9:51 AM To:
'Hale, Steve'; COSTEDIO, JAMES; 'Flentje, Fritzie'
Subject:
Draft - Request for Additional Information from Technical Specification Branch RE: Non-conservative Setpoint Changes
- Steve, By letter to the U.S. Nuclear Regulatory Commission (NRC) dated April 7, 2009, FPL Energy Point Beach, LLC, submitted a request to change technical specifications due to correcting non-conservative setpoints. This was originally part of the extended power uprate request, but was separated out by the NRC staff.
The Technical Specification Branch has reviewed the information provided and determined that in order to complete its evaluation, additional information is required. We would like to discuss the questions, in draft form below, with you in a conference call.
This e-mail aims solely to prepare you and others for the proposed conference call. It does not convey a formal NRC staff position, and it does not formally request for additional information.
Justin C. Poole Project Manager NRR/DORL/LPL3-1 U.S. Nuclear Regulatory Commission (301)415-2048 email: Justin.Poole@nrc.gov
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DRAFT
- 1.
Explain how the proposed use of the Limited Safety System Setting (LSSS) term in TS Table 3.3.1-1 and Table 3.3.2-1 is in accordance with10 CFR 50.36(c)(ii)(A), as well as existing TS actions.
Background:
The LAR proposes to replace the term Allowable Value with the term Limited Safety System Setting in the columns for TS Table 3.3.1-1 (Reactor Protection System (RPS)) and Table 3.3.2-1 (Engineered Safety Feature Actuation System (ESFAS)).
As a result, the proposed LSSS column will contain allowable values (i.e. values that contain margin to account for uncertainties associated with trip settings).
Defining the LSSS as an allowable value as opposed to a trip setting is inconsistent with the definition of LSSS in 10 CFR 50.36(c)(ii)(A). 10 CFR 50.36(c)(ii)(A) states Limiting safety system settings for nuclear reactors are settings for automatic protective devices related to those variables having significant safety functions. Where a limiting safety system setting is specified for a variable on which a safety limit has been placed, the setting must be so chosen that automatic protective action will correct the abnormal situation before a safety limit is exceeded.
In addition, the proposal appears to conflict with the current actions in Note 3.b of Table 3.3.1-1 and Note 1.b of Table 3.3.2-1. The current Notes refer to the LSSS as being the trip setting.
TSTF-493, Revision 4, Clarify Application of Setpoint Methodology for LSSS Functions, is currently being developed by the Owners Groups and is the result of a major joint effort between the industry and the NRC in resolving instrument setpoint methodology and LSSS issues. The licensees proposed definition of LSSS is also not in accordance with the joint industry / NRC efforts which reflect the NRCs position on 10 CFR 50.36(c)(ii)(A). Pertinent documents relevant to the development of TSTF-493, Revision 4, are:
NRC Reply to Industry Plan to Resolve TSTF-493, Clarify Application of Setpoint Methodology for LSSS Functions. March 9, 2009 (ML090560592)
Industry Plan to Resolve TSTF-493, Clarify Application of Setpoint Methodology for LSSS Functions. February 23, 2009 (ML090540849)
NRC Issues with TST-493, Revision 3. November 4, 2008 (ML082800484)
TSTF-493, Revision 3, Clarify Application of Setpoint Methodology for LSSS Functions. January 18, 2008 (ML080180441)
It is unclear how the licensees proposed use of the LSSS term is in accordance with10 CFR 50.36(c)(ii)(A), current TS actions, or joint industry / NRC efforts.
- 2.
Explain why the Underfrequency Bus A01 and A02 reactor trips are no longer proposed to be associated with the operability of the P-7 interlock.
Background:
TS Table 3.3.1-1 (RPS) contains Function 17.b, Reactor Trip System Interlock - Low Power Reactor Trips Block, P-7. The Bases provides a description of the reactor trips that the P-7 interlock automatically enables and disables. The Bases deletes the reference to the Underfrequency Bus A01 and A02 trips. However, no justification for this change appears to be provided in the submittal. In addition, the Bases for Function 12 Underfrequency Bus A01 and A02, indicates that the P-7 interlock still automatically enables and disables this reactor trip function.
10 CFR 50.36(c)(ii)(A) states Limiting safety system settings for nuclear reactors are settings for automatic protective devices related to those variables having significant safety functions. Where a limiting safety system setting is specified for a variable on which a safety limit has been placed, the setting must be so chosen that automatic protective action will correct the abnormal situation before a safety limit is exceeded.
It is unclear why the Underfrequency Bus A01 and A02 reactor trips are no longer proposed to be associated with the operability of the P-7 interlock.
DRAFT