ML040700440

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Technical Specification 3.4b, Auxiliary Feedwater System, Interpretation
ML040700440
Person / Time
Site: Kewaunee Dominion icon.png
Issue date: 04/18/2004
From: John Lamb
NRC/NRR/DLPM/LPD3
To: Raghavan L
NRC/NRR/DLPM/LPD3
References
TAC MC2263
Download: ML040700440 (3)


Text

April 18, 2004 MEMORANDUM TO: L. Raghavan, Section Chief, Section 1 Project Directorate III Division of Licensing Project Management Office of Nuclear Reactor Regulation FROM: John G. Lamb, Project Manager, Section 1 Project Directorate III /RA/

Division of Licensing Project Management Office of Nuclear Reactor Regulation

SUBJECT:

KEWAUNEE NUCLEAR POWER PLANT - TECHNICAL SPECIFICATION 3.4.B, AUXILIARY FEEDWATER SYSTEM, INTERPRETATION (TAC NO. MC2263)

The purpose of this letter is to inform you of the Nuclear Regulatory Commission (NRC) staffs interpretation of the Kewaunee Nuclear Power Plant (KNPP) Technical Specification (TS) 3.4.b, Auxiliary Feedwater System [AFW].

During the review of the stretch power uprate, the NRC questioned Nuclear Management Company, LLCs (NMCs) interpretation of KNPP TS 3.4.b.4 which states the following:

When the reactor coolant system temperature is > 350 EF, any of the following conditions of inoperability may exist during the time interval specified:

A. One auxiliary feedwater train may be inoperable for 72 hours8.333333e-4 days <br />0.02 hours <br />1.190476e-4 weeks <br />2.7396e-5 months <br />.

B. Two auxiliary feedwater trains may be inoperable for 4 hours4.62963e-5 days <br />0.00111 hours <br />6.613757e-6 weeks <br />1.522e-6 months <br />.

C. One steam supply to the turbine-driven auxiliary feedwater pump may be inoperable for 7 days.

KNPP TS 3.4.b basis states:

The turbine-driven AFW pump is required to be OPERABLE with redundant steam supplies from each of two main steamlines upsteam of the main steam isolation valves and shall be capable of taking suction from the Service Water System and supplying AFW to both of the steam generators.

NMC interprets KNPP TS 3.4.b.4 to mean that the licensee can be in Condition A and Condition C simultaneously.

The NMCs interpretation of KNPP TS 3.4.b.4 is non-conservative.

NMCs interpretation of TS 3.4.b.4 could result in the plant being in a 72-hour action requirement with only one motor-driven AFW pump operable, and not be able to mitigate the design-basis main steamline break event inside containment. This would be the case any time that the operable motor-driven AFW pump and the operable steam supply to the turbine-driven AFW pump are aligned to the same steam generator (SG) and it is that SG with which the fault is associated.

L. Raghavan While the TS Bases makes it clear that the steam supplies from both SGs have to be OPERABLE as a condition of operability for the turbine-driven AFW pump, the NRC staff notes that TS 3.4.b.4 does not clearly state this condition of operability. The TS 3.4.b.4 requirements may be misinterpreted and applied in a non-conservative manner. The NRCs interpretation of the KNPP TS is that if one steam supply to the turbine-driven AFW pump becomes inoperable, the turbine-driven AFW pump is considered to be inoperable; however, the TS allows a 7-day allowed outage time to resolve the problem (see Condition C, above). However, if a motor-driven AFW pump becomes inoperable during the period when the steam supply to the turbine-driven AFW pump is inoperable, two AFW pumps are considered to be inoperable. That is to say, in addition to being in the 7-day action requirement (Condition C) for the inoperable steam supply to the turbine-driven AFW pump and entering the 72-hour action requirement for the inoperable motor-driven AFW pump (see Condition A, above), the 4-hour action requirement for two inoperable AFW pumps would also apply (see Condition B, above).

NMC acknowledged the NRCs concern and documented it in their Corrective Action Process (CAP) for tracking and resolution (CAP020151, dated February 25, 2004).

Docket No. 50-305 cc: See next page

ML040700440

  • See previous concurrence OFFICE PDIII-1/PM PDIII-1/LA SPLB/SC IROB/SC OGC PDIII-1/SC NAME *JLamb THarris *DSolorio *TBoyce *AHodgdon LRaghavan DATE 04/07/04 04/14/04 03/19/04 03/29/04 04/06/04 04/14/04