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 Exelon Generation Co
honcharik , J NRR/DORL, 415-1157
References
TAC MD2166, TAC MD2167
Download: ML062760134 (5)

Text

October 3, 2006 Mr. 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 FOR ADDITIONAL 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 supplemented by 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 Power Station, Units 2 and 3.

The NRC staff is reviewing your submittal and has determined that additional information is required 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 help ensure sufficient time is available for staff review and contribute toward the NRCs goal of efficient 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 Regulation Docket Nos. 50-237 and 50-249

Enclosure:

Request for Additional Information cc w/encl: See next page

October 3, 2006 Mr. 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 FOR ADDITIONAL 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 supplemented by 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 Power Station, Units 2 and 3.

The NRC staff is reviewing your submittal and has determined that additional information is required 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 help ensure sufficient time is available for staff review and contribute toward the NRCs goal of efficient 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 Regulation Docket Nos. 50-237 and 50-249

Enclosure:

Request for Additional Information cc w/encl: See next page DISTRIBUTION:

PUBLIC LPL3-2 R/F RidsNrrDorlLpl3-2 RidsNrrPMJHoncharik RidsNrrLADClarke RidsAcrsAcnwMailCenter RidsOgcRp RidsRgn3MailCenter RidsNrrDorlDpr RidsNrrDssSbwb BParks, NRR ADAMS Accession Number: ML062760134 NRR-088 OFFICE LPL3-2/PM LPL3-2/LA SBWB/BC LPL3-2/BC NAME JHoncharik:mw DClarke GCranston DCollins DATE 10/3/06 10/3/06 10/3/06 10/3/06 OFFICIAL RECORD COPY

Dresden Nuclear Power Units 2 and 3 cc:

Site Vice President - Dresden Senior Vice President - Midwest Operations Exelon Generation Company, LLC Exelon Generation Company, LLC 6500 N. Dresden Road 4300 Winfield Road Morris, IL 60450-9765 Warrenville, IL 60555 Plant Manager - Dresden Nuclear Power Station Director - Licensing & Regulatory Affairs Exelon Generation Company, LLC Exelon Generation Company, LLC 6500 N. Dresden Road 4300 Winfield Road Morris, IL 60450-9765 Warrenville, IL 60555 Manager Regulatory Assurance - Dresden Vice President - Regulatory & Legal Affairs Exelon Generation Company, LLC Exelon Generation Company, LLC 6500 N. Dresden Road 4300 Winfield Road Morris, IL 60450-9765 Warrenville, IL 60555 U.S. Nuclear Regulatory Commission Assistant General Counsel Dresden Resident Inspectors Office Exelon Generation Company, LLC 6500 N. Dresden Road 200 Exelon Way Morris, IL 60450-9766 Kennett Square, PA 19348 Chairman Manager Licensing - Dresden Grundy County Board Exelon Generation Company, LLC Administration Building 4300 Winfield Road 1320 Union Street Warrenville, IL 60555 Morris, IL 60450 Regional Administrator, Region III U.S. Nuclear Regulatory Commission Suite 210 2443 Warrenville Road Lisle, IL 60532-4351 Illinois Emergency Management Agency Division of Disaster Assistance &

Preparedness 110 East Adams Street Springfield, IL 62701-1109 Document Control Desk - Licensing Exelon Generation Company, LLC 4300 Winfield Road Warrenville, IL 60555

REQUEST FOR ADDITIONAL INFORMATION DRESDEN NUCLEAR POWER STATION, UNITS 2 AND 3 DOCKET NOS. 50-237 AND 50-249 In reviewing the Exelon Generation Company, LLCs (Exelons) 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 Power Station, Units 2 and 3 (Dresden), the NRC staff has determined that the following information is needed in order to complete its review:

1. As discussed during teleconferences between the NRC staff and Exelon, the NRC staff requests 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 of the 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 NRC staff, 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 Regulations Section 50.55a, demonstrate that the SLCS pumps are operationally ready and capable of performing their intended function(s). (RAI Category 1.f)

Enclosure

RAI CATEGORIES (Select only one, most dominant category for each RAI question)

1. More information is needed because of:

a. complexity of request

b. first-of-a-kind nature of request

c. NRC change in regulatory significance or focus

d. NRC questions on previously used methodology or guidance

e. licensee change to previously used methodology

f. licensee reduction in current safety margin

2. The review can not be completed without additional explanation or clarification of:

a. input variables or analytical assumptions

b. methodology used or results obtained

c. applicability or bounding nature of third party analyses or data correlations

d. 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 inadequate

3. Reviewer requesting information even though the question is, or the question asks for:

a. not directly related to the request

b. 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 finding

f. information that is known to engineers who work in the general technical area

g. going beyond the current licensing basis and doesnt need to be asked

h. a formal commitment

4. Other (please specify)