ML101100628

Request for Additional Information, License Amendment Request, Revise Updated Safety Analysis Report to Modify Fire Protection Program for Use of Fire-Resistive Electrical Cable

ML101100628
Person / Time
Site:	Wolf Creek
Issue date:	05/06/2010
From:	Balwant Singal Plant Licensing Branch IV
To:	Matthew Sunseri Wolf Creek
Singal, Balwant, 415-3016, NRR/DORL/LPL4
References
TAC ME2966
Download: ML101100628 (8)

Text

UNITED STATES NUCLEAR REGULATORY COMMISSION WASHINGTON, D.C. 20555-0001 May 6, 2010 Mr. Matthew W. Sunseri President and Chief Executive Officer Wolf Creek Nuclear Operating Corporation Post Office Box 411 Burlington, KS 66839

SUBJECT:

WOLF CREEK GENERATING STATION - LICENSE AMENDMENT REQUEST FOR USE OF FIRE-RESISTIVE ELECTRICAL CABLE (TAC NO. ME2966)

Dear Mr. Sunseri:

By letter dated December 16, 2009 (Agencywide Documents Access and Management System (ADAMS) Accession No. ML093641067), Wolf Creek Nuclear Operating Corporation (WCNOC) submitted a license amendment request (LAR) to make changes to the approved fire protection program as described in the Wolf Creek Generating Station (WCGS) Updated Safety Analysis Report (USAR). Specifically, a deviation from certain technical commitments to Title 10 of the Code of Federal Regulations (10 CFR) Part 50, Appendix R.Section III.G.2, as described in Appendix 9.5E of the WCGS USAR, is requested regarding the use of fire-resistive cable at WCGS for certain power and control cables associated with two motor-operated valves on the Train B Component Cooling Water System.

Based on its review, the U.S. Nuclear Regulatory Commission (NRC) staff has determined that additional information is required to complete its evaluation of the LAR. The enclosure to this letter provides the staff request for additional information (RAI) that was sent to Ms. Diane Hooper of WCNOC via e-mail on March 26 and 31, 2010, and discussed with WCNOC staff on April 20, 2010. It was agreed that WCNOC will provide its RAI response within 30 days from the date of issuance of this letter.

The NRC staff considers that timely responses to RAls help ensure sufficient time is available for the staff to complete its review and contribute toward the NRC's goal of efficient and effective use of staff resources.

M. Sunseri -2 If you have any questions, please contact me at 301-415-3016 or via e-mail at balwant.singal@nrc.gov.

Sincerely, B~J.~se~~~ager Plant Licensing Branch IV Division of Operating Reactor Licensing Office of Nuclear Reactor Regulation Docket No. 50-482 Enclosure As stated cc w/encl: Distribution via Listserv

REQUEST FOR ADDITIONAL INFORMATION LICENSE AMENDMENT REQUEST FOR USE OF FIRE-RESISTIVE ELECTRICAL CABLES WOLF CREEK GENERATING STATION DOCKET NO. 50-482 By letter dated December 16,2009 (Agencywide Documents Access and Management System (ADAMS) Accession No. ML093641067), Wolf Creek Nuclear Operating Corporation (WCNOC) submitted a license amendment request (LAR) to make changes to the approved fire protection program as described in the Wolf Creek Generating Station (WCGS) Updated Safety Analysis Report (USAR). Specifically, a deviation from certain technical commitments to Title 10 of the Code of Federal Regulations (10 CFR) Part 50, Appendix R,Section III.G.2, as described in Appendix 9.5E of the WCGS USAR, is requested regarding the use of fire-resistive cable at WCGS for certain power and control cables associated with two motor-operated valves on the Train B Component Cooling Water System.

Based on its review, the U.S. Nuclear Regulatory Commission (NRC) has determined that the following additional information is required to complete its evaluation of the LAR.

Fire Protection Branch

1. The licensee states in its application that the proposed change" ...will not adversely affect the ability to achieve and maintain safe shutdown in the event of a fire." If the proposed installation would not adversely affect the ability to achieve and maintain safe shutdown in the event of a fire, please explain why the change would not fall under WCGS License Condition 2.C(5)(b).

2. Please provide a detailed summary of the analysis that demonstrates that the installed configurations will be bounded by the tested configurations with respect to electrical properties (voltage, current, conductor size, number of conductors, etc.) of the installed cables. The summary provided should include a discussion of key assumptions, methods, results, and conclusions.

3. In its application dated December 16, 2009, the licensee states that, WCNOC is proposing to route the new fire-resistive cable from the valves to the motor control center, which would include installation of the cable in Fire Areas A-16 and A-21. [Attachment I, page 3 of 13]

a. Does this indicate that the Meggitt cable is to be installed in all three (A-16, A-21, and A-27) fire areas? If so, please elaborate on the planned installation of Meggitt cable in fire areas A-16 and A-21.

Enclosure

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b. Do fire areas A-16 and A-21 require the same fire rating for the Meggitt cables that are proposed to be installed as the fire rating that is required in fire area A-27? If the fire resistance of the Meggitt cable is not required in the additional fire areas, please describe why the Meggitt is being installed in the additional areas.

c. If the Meggitt is not to be installed in the additional fire areas, please clearly describe what will be installed in each of the three fire areas.

4. In several places in its application, the licensee describes the use of Meggitt cable for 1-hour fire-rated applications. Examples include:

This testing demonstrated that the cable is capable of providing an equivalent level of protection as would be provided by a 3-hour and 1-hour rated fire barrier as described by Title 10 of the Code of Federal Regulations (10 CFR), Part 50, Appendix R,Section III.G.2.

[Attachment I, page 5 of 13]

The WCGS design specifies that fire-resistive cables required to only withstand a 1-hour fire are to be routed with the most practical routes along walls and ceilings. Fire detectors and automatic fire suppression systems are installed in the 1-hour fire areas, which mitigate the possibility of damage from equipment or material failing and falling onto the fire-resistive cable. [Attachment I, page 6 of 13]

The 600 volt fire-resistive control and power cables are type tested to 1925°F to verify 1 hour1.157407e-5 days <br />2.777778e-4 hours <br />1.653439e-6 weeks <br />3.805e-7 months <br /> and 3 hour3.472222e-5 days <br />8.333333e-4 hours <br />4.960317e-6 weeks <br />1.1415e-6 months <br /> fire ratings, and to verify environmental qualifications in accordance with NRC Generic Letter 86-10, Supplement 1. [Attachment II, page 10 of 17]

Fire-resistive cable, which has been successfully tested per the requirements of U.S. Nuclear Regulatory Commission (NRC) Generic Letter 86-10, Supplement 1, may be used in lieu of the rated fire barrier requirement in III.G.2.a and c. [Attachment II, page 17 of 17]

However, the majority of the application describes a specific 3-hour fire-rated installation.

a. Does the licensee also intend to install the Meggitt cable in lieu of 1-hour rated barriers, or in other 3-hour rated applications?

b. If so, please describe these additional applications in detail.

c. If not, the application should be amended to remove references to other installations.

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5. On page 8.3-29 of its application, related to the proposed modification to the WCGS USAR, the licensee states:

Openings in solid floors for vertical runs of cables are sealed with fire resistant material with the exception of 600 volt fire-resistive control and power cables which are routed independent of raceways. [Attachment II to the application, page 12 of 17]

a. Please describe in detail the relationship between this change and the requested licensing action.

b. If there is no relationship, please retract this change from the application or explain why it is appropriate.

c. If this change is related to the application, please provide a detailed summary of the plant-specific analyses that demonstrates the acceptability of unsealed openings in fire area boundaries, and other rated barriers, related to Meggitt cables, as described above. The summary provided should include a discussion of key assumptions, methods, results, and conclusions.

6. In the Regulatory Evaluation section of the application, the licensee states:

Paragraph (e) states "Nuclear power plants licensed to operate after January 1, 1979, shall. .. satisfy Criterion 3 of Appendix A to this part in accordance with the provisions of their licenses." [Attachment I, page 11 of 13]

Paragraph 50.48(e) of 10 CFR is no longer in force, and was removed nearly 10 years ago (65 FR 38190, June 20,2000).

a. Please revise the Regulatory Evaluation to ensure that only currently in-force regulations are referenced, or provide an explanation for the use of obsolete references. In addition, please ensure that the descriptions of regulation sections are accurate (e.g., the description of the 10 CFR III.G.2. requirements).

7. In its application, the licensee references a precedent, but does not relate the precedent to its different licensing basis for WCGS:

Amendment No. 123 to Shearon Harris Nuclear Power Plant, Unit 1 Facility Operating License No. NPF-62 approved the use of fire-resistive electrical cables in lieu of alternatives specified in Section C5.b.2 of Branch Technical Position Chemical Engineering Branch 9.5-1 for certain volume control tank outlet valves.

a. Please revise the discussion to clearly relate the requirements that the precedent is satisfying to those in the WCGS licensing basis that are of concern in the current application.

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8. In its application, the licensee proposed an addition to the WCGS Fire Hazard Analysis (FHA), page 17 of 274:

Safety-related cable in the general plant area is qualified to Institute of Electrical and Electronics Engineers (IEEE) 383-1974. All single conductors inside control panels meet the flame resistance requirements of Insulated Power Cable Engineers Association (IPCEA) S-19-81 or S-61-402, or Military Specification MIL-W-810044B3." [Attachment III, page 5 of 27]

a. Please describe in detail the relationship between this change and the requested licensing action.

b. If there is no relationship, please retract this change from the application, or explain why it is appropriate.

Electrical Engineering Branch

9. On page 3 of the LAR, the licensee stated:

The cables are purchased as safety related, seismically-qualified, environmentally-qualified, Class 1 E cables, which meet the 3-hour fire endurance rating when tested per the requirements of Supplement 1 to Generic Letter 86-10, "Implementation of Fire Protection Requirements,"

(Reference 6.1). For the proposed application, the cables are not used in a harsh environment and therefore, are not required to be environmentally qualified.

However, as noted on page 5 of Attachment II to the LAR, the licensee proposed adding the new fire-resistive cables to Table 3.11 (B)-3 (Sheet 68) of Section 3.11 of WCGS's USAR. Specifically, these cables are described as being required to function during a high energy line break accident (as denoted by the letter 'A' in the Category column).

a. Please explain the apparent discrepancy.

10. This question is only applicable if the new fire-resistive cables are required to meet NRC's environmental qualification requirements. On page 5 of the LAR, the licensee stated:

The cables are type Si2400 manufactured by Meggitt Safety Systems, Inc. This cable has demonstrated that it is capable of operating continuously for three hours during the most severe design basis fire, and it satisfies the other design considerations such as environmental qualification, seismic, and electrical characteristics.

a. Please provide a summary of your environmental qualification technical analysis.

In your response, provide details that demonstrate that the new fire-resistive cables will perform their design function under postulated design bases events

-5 (i.e., loss-of-coolant accident, high energy line break, and main steam line break). Also, please provide the environmental qualification profiles for each

. area that these cables will be located to show that the new fire-resistive cables will be bounded by the original assumptions.

b. Please describe whether the conventional cables that the new fire-resistive cables will be connected to are environmentally qualified.

c. Please describe the impact of connecting (i.e., splicing) the new fire-resistive cables to the existing conventional cables (i.e., the impact on both the new fire resistive cables and the conventional cables) on the environmental qualification of each type of cable.

d. Please describe whether the splices and supports are environmentally qualified.

e. Please describe how the new fire-resistive cables will be protected from water and chemical sprays.

M. Sunseri -2 If you have any questions, please contact me at 301-415-3016 or via e-mail at balwant.singal@nrc.gov.

Sincerely, IRAJ Balwant K. Singal, Senior Project Manager Plant Licensing Branch IV Division of Operating Reactor Licensing Office of Nuclear Reactor Regulation Docket No. 50-482 Enclosure As stated cc w/encl: Distribution via Listserv DISTRIBUTION:

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