GNRO-2010/00009, Technical Specification Bases Update to the NRC for Period Dated January 20, 2009

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Technical Specification Bases Update to the NRC for Period Dated January 20, 2009
ML100210330
Person / Time
Site: Grand Gulf Entergy icon.png
Issue date: 01/20/2010
From: Burford F
Entergy Operations
To:
Document Control Desk, Office of Nuclear Reactor Regulation
References
GNRO-2010/00009
Download: ML100210330 (4)
v • d • e


Text

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-===- Entergy Operations Entergy Operations, Inc.

Po. Box 756 Port Gibson, MS 39150 Tel 601-437 -2800 GNRO-2010/00009 January 20, 2010 u.s. Nuclear Regulatory Commission Attn: Document Control Desk Washington, D.C. 20555-0001 SUbject: Technical Specification Bases Update to the NRC for Period Dated January 20, 2009 Grand Gulf Nuclear Station, Unit 1 Docket No. 50-416 License No. NPF-29

Dear Sir or Madam:

Pursuant to Grand Gulf Nuclear Station (GGNS) Technical Specification 5.5.11, Entergy Operations, Inc. hereby submits an update of all changes made to GGNS Technical Specification Bases since the last submittal (GNRO-2009/00028 dated April 22, 2009, to the NRC from GGNS). This update is consistent with update frequency listed in 10CFR50.71 (e).

This letter does not contain any commitments.

If you have any questions, please contact Peggy R. Rescheske at (601) 437-1781.

ij~

F.G. Burford Acting - Licensing Manager FGB\PRR

Attachment:

GGNS Technical Specification Bases cc: (See Next Page)

GNR0-2010100009 Page 2 cc:

NRC Senior Resident Inspedor Grand Gulf Nuclear Station Port Gibson, MS 39150 u.s. Nuclear Regulatory Commission AnN: Mr. Elmo E. Collins, Jr. (w/2)

Regional Administrator, Region IV 612 East Lamar Blvd, Suite 400 Arlington, TX 76011-4005 u.S. Nuclear Regulatory Commission AnN: Mr. Carl F. Lyon, NRRlADROIDORL (w/2)

Mail Stop OWFN/8 B1 Washington, D.C. 20555-001

ATTACHMENT to GNRO-2010100009 Grand Gulf Technical Specification Bases LBDCR# BASES PAGES AFFECTED TOPIC of CHANGE 2010-001 B 3.3-79 Implements BWROG-113, Rev. 0, TSTF-516-T

ATWS-RPT Instrumentation B 3.3.4.2 BASES (continued)

APPLICABLE The ATWS-RPT initiates an RPT to aid in preserving the SAFETY ANALYSES, integrity of the fuel cladding following events in which LCO, and scram does not, but should, occur. Based on its APPLICABILITY contribution to the reduction of overall plant risk, the instrumentation is included as required by the NRC Policy Statement.

The OPERABILITY of the ATWS-RPT is dependent on the OPERABILITY of the individual instrumentation channel Functions. Each Function must have a required number of OPERABLE channels in each trip system, with their setpoints within the specified Allowable Value of SR 3.3.4.2.4. The actual setpoint is calibrated consistent with applicable setpoint methodology assumptions. Channel OPERABILITY also includes the associated recirculation pump drive motor breakers. A channel is inoperable if its actual trip setpoint is not within its required Allowable Value.

Allowable Values are specified for each ATWS-RPT Function specified in the LCD. Nominal trip setpo;nts are specified in the setpoint calculations. The nominal setpoints are selected to ensure the setpoints do not exceed the Allowable Value between CHANNEL CALIBRATIONS. Operation with a trip setpoint less conservative than the nominal trip setpoint, but within its Allowable Value, is acceptable. Trip setpoints are those predetermined values of output at which an action should take place. The setpoints are compared to the actual process parameter (e.g., reactor vessel water level), and when the measured output value of the process parameter exceeds the setpoint, the associated device (e.g.,

trip unit) changes state. The analytic limits are derived from the limiting values of the process parameters obtained from the safety analysis. The Allowable Values are derived from the analytic limits corrected for calibration, process, and some of the instrument errors. The trip setpoints are then determined accounting for the remaining instrument errors (e.g., drift). The trip setpoints derived in this manner provide adequate protection because instrumentation uncertainties, process effects, calibration tolerances, instrument drift, and severe environment errors (for channels that must function in harsh environments as defined by 10 CFR 50.49) are accounted for.

The individual Functions are required to be OPERABLE in MODE 1 to protect against common mode failures of the (continued)

GRAND GULF B 3.3-79 LBDCR 10001

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