ML062760134

RAI Related to Standby Liquid Control System

ML062760134
Person / Time
Site:	Dresden
Issue date:	10/03/2006
From:	John Honcharik NRC/NRR/ADRO/DORL/LPLIII-2
To:	Crane C M Exelon Generation Co
honcharik , J NRR/DORL, 415-1157
References
TAC MD2166, TAC MD2167
Download: ML062760134 (5)

Text

October 3, 2006Mr. Christopher M. Crane, President and Chief Nuclear Officer Exelon Generation Company, LLC 4300 Winfield Road Warrenville, IL 60555

SUBJECT:

DRESDEN NUCLEAR POWER STATION, UNITS 2 AND 3 - REQUEST FORADDITIONAL INFORMATION RELATED TO STANDBY LIQUID CONTROL SYSTEM (TAC NOS. MD2166 AND MD2167)

Dear Mr. Crane:

By letter to the Nuclear Regulatory Commission (NRC) dated June 2, 2006, as supplementedby letter dated August 18, 2006, Exelon Generation Company, LLC submitted a request to revise the technical specification surveillance requirements, to increase the enrichment of the sodium pentaborate used in the standby liquid control system, for the Dresden Nuclear PowerStation, Units 2 and 3.The NRC staff is reviewing your submittal and has determined that additional information isrequired to complete the review. The specific information requested is addressed in the enclosure to this letter. During a discussion with your staff on September 29, 2006, it was agreed that you would provide a response within 10 days from the date of this letter. The NRC staff considers that timely responses to requests for additional information helpensure sufficient time is available for staff review and contribute toward the NRC's goal ofefficient and effective use of staff resources. If circumstances result in the need to revise the requested response date, please contact me at (301) 415-1157.Sincerely,/RA/John Honcharik, Project Manager Plant Licensing Branch III-2 Division of Operating Reactor Licensing Office of Nuclear Reactor RegulationDocket Nos. 50-237 and 50-249

Enclosure:

Request for Additional Informationcc w/encl: See next page October 3, 2006Mr. Christopher M. Crane, President and Chief Nuclear Officer Exelon Generation Company, LLC 4300 Winfield Road Warrenville, IL 60555

SUBJECT:

DRESDEN NUCLEAR POWER STATION, UNITS 2 AND 3 - REQUEST FORADDITIONAL INFORMATION RELATED TO STANDBY LIQUID CONTROL SYSTEM (TAC NOS. MD2166 AND MD2167)

Dear Mr. Crane:

By letter to the Nuclear Regulatory Commission (NRC) dated June 2, 2006, as supplementedby letter dated August 18, 2006, Exelon Generation Company, LLC submitted a request to revise the technical specification surveillance requirements, to increase the enrichment of the sodium pentaborate used in the standby liquid control system, for the Dresden Nuclear PowerStation, Units 2 and 3.The NRC staff is reviewing your submittal and has determined that additional information isrequired to complete the review. The specific information requested is addressed in the enclosure to this letter. During a discussion with your staff on September 29, 2006, it was agreed that you would provide a response within 10 days from the date of this letter. The NRC staff considers that timely responses to requests for additional information helpensure sufficient time is available for staff review and contribute toward the NRC's goal ofefficient and effective use of staff resources. If circumstances result in the need to revise the requested response date, please contact me at (301) 415-1157.Sincerely,/RA/John Honcharik, Project Manager Plant Licensing Branch III-2 Division of Operating Reactor Licensing Office of Nuclear Reactor RegulationDocket Nos. 50-237 and 50-249

Enclosure:

Request for Additional Informationcc w/encl: See next pageDISTRIBUTION:PUBLICLPL3-2 R/FRidsNrrDorlLpl3-2 RidsNrrPMJHoncharikRidsNrrLADClarkeRidsAcrsAcnwMailCenter RidsOgcRpRidsRgn3MailCenterRidsNrrDorlDprRidsNrrDssSbwbBParks, NRRADAMS Accession Number: ML062760134NRR-088OFFICELPL3-2/PMLPL3-2/LASBWB/BCLPL3-2/BC NAMEJHoncharik:mwDClarkeGCranstonDCollins DATE10/3/0610/3/0610/3/0610/3/06OFFICIAL RECORD COPY Dresden Nuclear Power Units 2 and 3 cc:

Site Vice President - DresdenExelon Generation Company, LLC 6500 N. Dresden Road Morris, IL 60450-9765Plant Manager - Dresden Nuclear Power StationExelon Generation Company, LLC 6500 N. Dresden Road Morris, IL 60450-9765Manager Regulatory Assurance - DresdenExelon Generation Company, LLC 6500 N. Dresden Road Morris, IL 60450-9765U.S. Nuclear Regulatory CommissionDresden Resident Inspectors Office 6500 N. Dresden Road Morris, IL 60450-9766ChairmanGrundy County Board Administration Building 1320 Union Street Morris, IL 60450Regional Administrator, Region IIIU.S. Nuclear Regulatory Commission Suite 210 2443 Warrenville RoadLisle, IL 60532-4351Illinois Emergency Management Agency Division of Disaster Assistance &

Preparedness 110 East Adams Street Springfield, IL 62701-1109Document Control Desk - LicensingExelon Generation Company, LLC 4300 Winfield Road Warrenville, IL 60555Senior Vice President - Midwest Operations Exelon Generation Company, LLC 4300 Winfield Road Warrenville, IL 60555Director - Licensing & Regulatory AffairsExelon Generation Company, LLC 4300 Winfield Road Warrenville, IL 60555Vice President - Regulatory & Legal AffairsExelon Generation Company, LLC 4300 Winfield Road Warrenville, IL 60555Assistant General CounselExelon Generation Company, LLC 200 Exelon Way Kennett Square, PA 19348Manager Licensing - DresdenExelon Generation Company, LLC 4300 Winfield Road Warrenville, IL 60555 EnclosureREQUEST FOR ADDITIONAL INFORMATIONDRESDEN NUCLEAR POWER STATION, UNITS 2 AND 3DOCKET NOS. 50-237 AND 50-249In reviewing the Exelon Generation Company, LLC's (Exelon's) submittal dated June 2, 2006,as supplemented by letter dated August 18, 2006, related to the proposed revision to the technical specification surveillance requirements to increase the enrichment of the sodium pentaborate used in the standby liquid control system (SLCS), for the Dresden Nuclear PowerStation, Units 2 and 3 (Dresden), the NRC staff has determined that the following information isneeded in order to complete its review:1.As discussed during teleconferences between the NRC staff and Exelon, the NRC staffrequests that Exelon submit a commitment to perform a one-time pump test, prior to implementing this amendment, with the flow recorded at a sufficiently high pressure and flow rate to demonstrate, after density correction, that the design-basis requirements ofthe SLCS pumps have been met. In addition, provide the pressure and flow rate that will be used for this one-time pump test. (RAI Category 1.f)2.On August 31, 2006, during a telephone conference call between Exelon and the NRCstaff, Exelon discussed its testing program for the SLCS pumps that follow the requirements of the American Society of Mechanical Engineers Operation and Maintenance Code (ASME OM Code). Regarding the acceptance criteria for inservice testing, confirm that the testing and test acceptance criteria used in the ASME OM Code testing of the SLCS pumps, as required by Title 10 of the Code of Federal RegulationsSection 50.55a, demonstrate that the SLCS pumps are operationally ready and capableof performing their intended function(s). (RAI Category 1.f) RAI CATEGORIES(Select only one, most dominant category for each RAI question)1.More information is needed because of:a. complexity of requestb. first-of-a-kind nature of request

c. NRC change in regulatory significance or focusd. NRC questions on previously used methodology or guidancee. licensee change to previously used methodology

f. licensee reduction in current safety margin2.The review can not be completed without additional explanation or clarification of:a. input variables or analytical assumptionsb. methodology used or results obtained

c. applicability or bounding nature of third party analyses or data correlationsd. differences from NRC guidance documents (SRP, RG, etc.)e. no significant hazards consideration discussion

f. environmental considerations discussion

g. applicable regulatory requirements discussion

h. information that appears to be incorrect and needs to be corrected

i. response to previous RAI appears inadequate3.Reviewer requesting information even though the question is, or the question asks for:a. not directly related to the requestb. inconsistent with applicable codes, standards, RGs, or SRP sections

c. information accessible from readily available sources and was explicitly referenced

d. information does not appear needed given the precedent cases discussed in the request

e. information that is not safety significant or pertinent to the regulatory findingf. information that is known to engineers who work in the general technical area

g. going beyond the current licensing basis and doesn't need to be asked

h. a formal commitment4.Other (please specify)