ML20100J839

Proposed Tech Specs Re Safety Setpoint Tolerance Requirements for Safety/Relief Valves

ML20100J839
Person / Time
Site:	Grand Gulf
Issue date:	02/22/1996
From:	ENTERGY OPERATIONS, INC.
To:
Shared Package
ML20100J816	List: ML20100J813 ML20100J831 ML20100J839 ML20100J862
References
NUDOCS 9602290272
Download: ML20100J839 (2)

Text

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l- l GNRO 96/00008 Att: chm:nt 3 l- Page 1 of 2

! S/RVs

' 3.4.4 i

> 3.4 REACTOR COOLANT SYSTEM (RCS) 3.4.4 Safety / Relief Valves (S/RVs)

LCO 3.4.4 The safety function of seven S/RVs shall be OPERABLE, M

The relief function of six additional S/RVs shall be .

OPERABLE.

APPLICABILITY: MODES 1, 2, and 3.

ACTIONS CONDITION REQUIRED ACTION COMPLETION TIME A. One or w re required A.1 Be in MODE 3. 12 hours1.388889e-4 days <br />0.00333 hours <br />1.984127e-5 weeks <br />4.566e-6 months <br /> S/RVs '.noperable.

8!E A.2 Be in MODE 4. 36 hours4.166667e-4 days <br />0.01 hours <br />5.952381e-5 weeks <br />1.3698e-5 months <br /> -

SURVEILLANCE REQlIREMENTS SURVEILLANCE FREQUENCY SR 3.4.4.1 Verify the safety function lift setpoints In accordance i of the required S/RVs are as follows: with the inservice  ;

Number of Setpoint Testing Program j S/RVs (osia) 8 1165 t . 3'4.9 6 1180 t the ;35.9 6 1190 i R 4 '35.7 con nu@

9602290272 960222 PDR ADOCK 05000416 P PDR GRAND GULF 3.4-10 Amendment tio.120

f.

. GNRO 96/00008 Attachmtnt 3 B 1

Page 2 of 2 l

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l BASES (continued)

i. APPLICABLE The overpressure protection system must accommodate the P SAFETY ANALYSES most severe pressure transient. Evaluations have determined i that the 90st severe transient is the closure of all main

steam isolation valves (MSIVs) followed by reactor scram on

} high neutron flux (i.e., failure of the direct scram ,

associated with MSIV position) (Ref. 2). For the purpose of l the analyses, six of the S/RVs are assumed to operate in the i relief mode, and seven in the safety mode. The analysis results demor. strate that the design S/RV capacity is capable ,

of maintaining reactor pressure below the ASME Code limit of 110% of vessel design pressure (110% x 1250 psig =

1375 psig). This LCO helps to ensure that the acceptance ,

limit of 1375 psig is met during the design basis event.

Reference 3 discusses additional events that are expected to actuate the S/RVs. Fron'an overpressure standpoint, the i design basis events are bounded by.the MSIV closure with flux scrac event described above.

S/RVs satisfy Criterion 3 of the NRC Policy Statement.  ;

LCO The safety function of seven S/RVs is required to be OPERABLE in the safety mode, and an additional six S/RVs i (other than the seven S/RVs that satisfy the safety '

i function) must be OPERABl.E in the relief mode. The requirements of this LC0 are applicable only to the l capability of the S/RVs to mechanically open to relieve I excess pressure. In Reference 2, an evaluation was performed to establish the parametric relationship between the peak vessel pressure and the number of OPERABLE S/RVs.

The results show that with a minimos of seven S/RVs in the safety mode and six S/RVs in the relief mode OPERABLE, the ASME Code limit of 1375 psig is not exceeded.

The S/RV setpoints are established to ensure the ASME Code limit on peak reactor pressure is satisfied. . The ASME Code specifications require the lowest safety valve be set at or below vessel design pressure (1250 psig) and the highest safety valve be set so the total accumulated pressure does not exceed 110% of the design pressure for conditions. The transient evaluations in Reference 3 are based on these se ints, but also include the additional uncertainties of of the nominal setpoint to account for potential l 3% setpoint drift to provide an added degree of conservatism.

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(continued) l GRAND GULF B 3.4-18 Revision No. 0

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