IR 05000298/1998002

Errata to Insp Rept 50-298/98-02,dtd 980515.Changes Have Been Made to Fourth Paragraph

ML20249A807
Person / Time
Site:	Cooper
Issue date:	06/11/1998
From:	NRC OFFICE OF INSPECTION & ENFORCEMENT (IE REGION IV)
To:
Shared Package
ML20249A052	List: IR 05000298/1998002 ML20249A051
References
50-298-98-02, 50-298-98-2, NUDOCS 9806180267
Download: ML20249A807 (1)

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steam flow required to maintain peak critical centerline temperature less than 1500*F for an uncovered core, (3) maximum time before peak centerline temperature exceeds 1500*F for an uncovered core referenced to POHGH equal 13.4 kw/ft,~ (4) the cold shutdown boron concentration requirements, and (5) the , hot shutdown boron

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concentration requirement. The emergency operating procedure parameters ultimately L ' effected by these concems were listed as the boron injection initiation temperature, cold L shutdown boron wait, peak capacity level limit, heat capacity temperature limit, hot shutdown boron weight, minimum alternate reactor pressure vessel flooding pressure, L minimum core flooding interval, maximum core uncovery time limit, minimum number of safety relief valves required for emergency depressurization, minimum reactor pressure vessel flooding pressure, minimum steam cooling reactor pressure vessel water level, l minimum zero reactor pressure vessel water level, peak centerline temperature,

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pressure-suppression pressure, and peak linear heat generation rate. The licensee had addressed only the top of active fuel parameter.-

The licensee issued Problem identification Report 2-27287 to document that an apparent discrepancy existed with the 0-inch level assumed as the top of active fuel in the vesse The licensee noted that 150-inch fuel potentially extended to above the zero leve The licensee evaluated the safety significance of the 6-inch nonconservative bias.

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Vendor testing had found that fuel peak centerline temperatures of 1800*F would not be -

reached until vessel water level dropped below -70 inches (below top of active fuel). The licensee performed an evaluation which considered various instrument errors, including errors expected in a harsh equipment qualification environment. They found that the 1800'F limit would rot be reached even with the 6-inch nonconservative instrument bia The failure to incorporate the correct fuel length design requirements in plant emergency operating procedures is an example of a violation of 10 CFR Part 50, Appendix B, Criterion V, which requires, in past, that procedures be appropriate to the circumstances (50-298/98002-02).

Additiona'l questions which remain to be resolved include: (1) Technical Specification interpretation 96-003 which documented that the fuel length indicated in Technical Specification was 144 inches, although the Updated Safety Analysis Report stated that active fuel length was 150 inches. The resolution associated with the interpretation

- concluded that the conversion to improved Technical Specifications would remove the

!" . ' associated figure which showed the top of active fuel relative to the 144-inch active fuel length. The recalculation of setpoints for improved Technical Specification would be done in accordance with General Electric setpoint methodology and instrument zero j would be redefined as a fixed point above the fuel which will be defined for the purposes '{

of level monitoring as top of active fuel. The interpretation stated that the reference in i the Technical Specification bases was not a basis for the limiting safety system setting .

and that safety margin for transient and accident analysis was maintained through I administrative controls such as higher trip setpoints and emergency operating 4 - procedures; This Technical Specification request dated June 8,1996, stated that the safety limit was maintained regarding General Electric setpoint methodology, inspectors i ADOCk r -

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