ML060740619

Supplement to 60-Day Response to Bulletin 2003-01, Potential Impact of Debris Blockage on Emergency Sump Recirculation at Pressurized-Water Reactors.

ML060740619
Person / Time
Site:	Point Beach
Issue date:	02/24/2006
From:	Koehl D L Nuclear Management Co
To:	Document Control Desk, Office of Nuclear Reactor Regulation
References
BL-03-001, NRC 2006-0023
Download: ML060740619 (4)

Text

NMC Committed to NudearExcelIIvh February 24, 2006 Point Beach Nuclear Plant Operated by Nuclear Management Company, LLC NRC 2006-0023 BL 2003-01 U.S. Nuclear Regulatory Commission ATTN: Document Control Desk Washington DC 20555 Point Beach Nuclear Plant, Units 1 and 2 Docket Nos. 50-266 and 50-301 License Nos. DPR-24 and DPR-27 Supplement to 60-Day Response to Bulletin 2003-01. "Potential Impact of Debris Blockage on Emermencv Sump Recirculation at Pressurized-Water Reactors"

References:

1)2)3)4)5)6)7)8)Letter from NMC to NRC dated August 8, 2003 (NRC 2003-0068)

Letter from NMC to NRC dated May 14, 2004 (NRC 2004-0050)

Letter from NMC to NRC dated August 19, 2005 (NRC 2005-0106)

Letter from NMC to NRC dated October 18, 2005 (NRC 2005-0134)

Letter from NMC to NRC dated December 19, 2005 (NRC 2005-0155)

Letter from NRC to NMC dated January 10, 2006 Letter from NMC to NRC dated January 17, 2006 (NRC 2006-0013)

Letter from NMC to NRC dated February 17,2006 (NRC 2006-0009)

In Reference 1, Nuclear Management Company, LLC (NMC), provided the 60-day response to Bulletin (BL) 2003-01, "Potential Impact of Debris Blockage on Emergency Sump Recirculation at Pressurized-Water Reactors," for the Point Beach Nuclear Plant (PBNP). References 2 though 4 supplemented the initial response.

Reference 5 committed to providing a supplement to the 60-day response by January 21, 2006.Reference 7 extended the commitment date to February 24, 2006, to accommodate the NMC response (Reference

8) to the Request for Additional Information (listed as Reference 6).The enclosure to this letter provides an update on implementation of Candidate Operator Actions (COAs) #5 and #6, and provides supplemental information regarding degraded containment coatings.6610 Nuclear Road

• Two Rivers, Wisconsin 54241 Teleplone 920.755.2321 fZJO'2 Document Control Desk Page 2 Summary of Commitments This letter contains no new commitments or revisions to existing commitments.

If you have any questions or desire further information regarding the subject matter of this letter, please contact me at (920)755-7624.

Dennis L. Koehl Site Vice-President, Point Beach Nuclear Plant Nuclear Management Company, LLC Enclosure cc: Administrator, Region 111, USNRC Project Manager, Point Beach Nuclear Plant, USNRC Resident Inspector, Point Beach Nuclear Plant, USNRC PSCW ENCLOSURE 1 SUPPLEMENT TO NRC BL 2003-01 Nuclear Management Company, LLC (NMC), provided the 60-day response to Bulletin (BL) 2003-01, "Potential Impact of Debris Blockage on Emergency Sump Recirculation at Pressurized-Water Reactors," for the Point Beach Nuclear Plant (PBNP) via Reference

1. References 2 through 4 supplemented the NMC initial response.

Reference 5 committed to providing a supplement to the 60-day response by January 21, 2006. Reference 7 extended the commitment date to February 24, 2006.On January 10, 2006, NMC received a request for additional information (RAI)associated with a 10) CFR 50.46 emergency core cooling system (ECCS) long-term cooling effects event notification reported to the Commission via Emergency Notification EN 42129. This RAI is identified as Reference

6. The NMC response to the RAI was submitted via letter dated February 17, 2006, as noted via Reference 8.Revised Candidate Operator Actions COA #5 Refill refueling water storage tank The intent of this COA is to provide inventory for re-establishing reactor coolant system (RCS) injection and containment spray (if necessary) in the event the containment sump source is not available.

The overall strategy is to refill the refueling water storage tank (RWST) following initiation of recirculation, or line up an alternate makeup source bypassing the RWST, in anticipation of possible sump blockage.As stated in Reference 4, NMC implemented this strategy at PBNP by providing instructions in the Emergency Operating Procedures (EOPs) to refill the RWST from normal or alternate water sources. Specifically, Attachment A of Emergency Contingency Action (ECA)-1.3, "Containment Sump Blockage," provides direction to refill the RWST from the following sources as available:

(1) chemical and volume control system (CVCS) blender; (2) fuel transfer canal; (3) CVCS holdup tanks; (4) opposite unit's RWST; and (5) boric acid storage tanks (BASTs).Via commitment made by NMC in Reference 4, direction has been included in emergency operating procedure (EOP)-1.3, "Transfer to Containment Sump Recirculation

-Low Head Injection," and EOP-1.4, "Transfer to Containment Sump Recirculation

-High Head Injection," to initiate refill of the RWST using the CVCS blender once the RWST has been depleted.

These procedure changes were implemented on December 13, 2005.Page 1 of 2 Is .COA #6 Inject more than one RWST volume from refilled/diluted RWST or by bypassing RWST The intent of this COA is to provide procedures for re-establishing injection to the RCS from either the refilled RWST or alternate makeup source. The overall strategy is to secure recirculation and align equipment to re-establish injection from a refilled RWST or from an alternate source bypassing the RWST.As previously stated in Reference 4, NMC implemented this strategy by directions contained in procedure ECA-1.3 that direct the establishment of high head safety injection (SI) by drawing from the RWST. Also, other than the containment accident sump, Severe Accident Management Guideline (SAMG) SAG-3, "Inject into the RCS," tabulates three potential SI pump suction sources and the necessary supporting equipment and conditions for each. These suction sources are the RWST, "A" and "C" BASTs and "B" BAS;T. Additionally, SAMIG SAG-3 tabulates six potential charging pump injection paths and the equipment necessary to support each as the RWST, Volume Control Tank (VCT), BAST via the Blender, BAST via the boration flow path, Reactor Makeup Water Tank (RMWT) via the Blender, and RMWT via the alternate dilution path.Although such actions would only be necessary for conditions beyond those contemplated in either the design or license basis of the facility, as committed in Reference 4, NMC revised procedure ECA-1.3 for re-establishing injection to the RCS utilizing the following potential alternate suction sources and/or injection paths: (1) residual heat removal (RHR) pumps from the RWST; (2) charging pumps from the RWST; (3) charging pumps from the VCT; (4) SI pumps from the BASTs.Attachment A of ECA-1.3 was also revised to include an option of making up to the RWST from the spent fuel pool. These procedure revisions were implemented on December 14, 2005.Degraded Containment Coatings As previously noted, Reference 6 transrmnitted a RAI concerning ECCS long-term cooling effects. RAI Question 3.A and its subparts contained several questions associated with containment coatings and the effects of failed coatings upon the ability to maintain long-term core cooling following a design basis accident.

The NMC response to Question 3A, as well as the response to Questions 1.A and 1.C provided the intended update of this letter regarding the status of containment coatings at PBNP. Please refer to Reference 8 for this information.

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