ML20198H812

Corrected Safety Evaluation Supporting Amend 63 to License NPF-57,correcting Error Re Description of Min Core Thermal Power & Flow Conditions to Avoid Thermal Stratification

ML20198H812
Person / Time
Site:	Hope Creek
Issue date:	12/18/1997
From:	NRC (Affiliation Not Assigned)
To:
Shared Package
ML20198H809	List: ML20198H804 ML20198H812
References
NUDOCS 9801130401
Download: ML20198H812 (2)

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-0 recirculation pumps at minimum speed are initial values established prior to startup testing. The proposed updates seek to incorporate final values,

a. Delta-w for single-loop operation Delta-w is defined as the difference in indicated drive flow (in percent of drive flow which produces rated core flow) between two-loop and single-loop operation. A conservative value h&s been determined based upon calculations following General Electric's (GE) guidelines using plant test data. This value is acceptable,

b. Minimum power corresponding to conditions in which no temperature

. stratification occurs Power ascension testing verified power and flow conditions during single-loop operation at which no temperature stratification occurred. Although the test data did not establish aci.ual minimum power and flow values for the onset of stratification, the data demonstrated that the surveillances required to check for stratification are not required above the proposed TS values of 38 percent thermal power and 50 percent of rated recirculation flow. These proposed updated values of single-loop power and flow limits of thermal stratification are conservative relative to actual plant test data and are acceptable,

c. Core flow with both recirculation pumps at minimum speed TS Figure 3.4.1.1-1 is the power to flow limit used to specify actions needed to detect or avoid limit cycle neutron flux oscillations. TS 3.4.1.1 contains Actions and Surveillance Requirements (SR) dealing with operation in the power ,

to flow region attributed to these oscillations. The current TS stipulates ,

neutron monitoring noise level surveillances to be performed between core flow  !

at ~mW5um recirculation pump speed up to the maximum flow defining the limit region. Corrective action to avoid oscillations is taken when flow is equal to or below that value. The proposed change revises this threshold from 39 percent to 40 percent of rated core flow, consistent with NRC Bulletin 88-07, Supplement-1, " Power Oscillations in Boiling Water Reactors" (Reference 4). 3 As this is the value specified in the Bulletin for the required actions, and the change to a higher flow is more conservative, the change is acceptable. l 2.3 Inhrical Soecification 3.0.5 l The licensee proposed the addition of Limiting Condition for Operation (LCO) 3.0.5 ano the associated bases-of NUREG-1433, " Standard Technical l

Specifirations General Electric Plants, BWR/4," to the Hope Creek Generating i Station TSs. The licensee requested this change in order to clarify the l intent of LCO 3.0.2 to prevent misinterpretation of the LC0 and associated  !

Bases. The new LCO states, " Equipment removed from service or declared l inoperable to comply with ACTIONS may be returned to service under j administrative control solely to perform testing required to demonstrate its )

ENCLOSURE 9801130401 971218 PDR ADOCK 05000354 P PDR

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activities will be conducted in compliance with the Commission's regulations, and (3) the issuance of the amendment will not be inimical to the conson defense and security or to the health and safety of the public.

Principal Contributors: J. Donoghue J. Zinnerman Date: January 25, 1994 Revised by letter dated Decamher 18. 1997

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