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Summary of January 25, 2007, Meeting with Dominion Energy Kewaunee Inc., on the Licensee'S Amendment Request Regarding the Use of Tormis Methodology (TAC No. MD1194)
	ML070330427
Person / Time
Site:	Kewaunee
Issue date:	02/26/2007
From:	Kuntz R F; NRC/NRR/ADRO/DORL/LPLIII-2
To:	;
	R. Kuntz LPL3-2
Shared Package
ML070570083	List: ML070330427;
References
	TAC MD1194
	Download: ML070330427 (5)
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February 26, 2007LICENSEE:Dominion Energy Kewaunee, Inc.

FACILITY:Kewaunee Power Station

SUBJECT:

SUMMARY

OF JANUARY 25, 2007, MEETING WITH DOMINION ENERGY KEWAUNEE INC., ON THE LICENSEE'S AMENDMENT REQUEST

REGARDING THE USE OF TORMIS METHODOLOGY (TAC NO. MD1194)

On January 25, 2007, a Category 1 public meeting was held between the U.S. Nuclear Regulatory Commission (NRC) and representatives of Dominion Energy Kewaunee, Inc. (the

licensee) at NRC Headquarters, One White Flint North, 11555 Rockville Pike, Rockville, Maryland. The purpose of the meeting was to discuss Dominion's license amendment for use

of the TORMIS methodology. A list of attendees is provided as Enclosure 1.

The licensee presented information (See Enclosure 2) pertaining to their license amendment request dated April 6, 2006 ((ADAMS) Accession No. ML061010151), which requested approval

to use the TORMIS methodology to assess the need for tornado missile protection for the

Kewaunee Power Station (KPS) emergency diesel generator (EDG) exhaust ducts and EDG

fuel oil tank vent lines. The licensee presented information pertaining to the analysis contained

in the original submital, as well as answers to questions the NRC staff had previously

communicated to the licensee (ADAMS Accession No. ML062850056).

The licensee presented background information that led to the amendment request. The NRC staff asked the licensee how they determined possible vulnerabilities to tornado- generated

missile strikes at KPS. The licensee responded by explaining that they did thorough walk-

downs of the site.

The licensee presented the layout of the turbine area where the EDG exhaust duct was located as well as the EDG fuel oil storage tank vent location. The licensee explained how they

shortened the EDG fuel oil storage tank vents to minimize the probability of tornado-generated

missile strikes, and to make the vents more stable. The licensee then gave a background of the

development and use of the TORMIS methodol ogy, and conservatisms in their analysis.

The licensee then presented their responses to the NRC staff questions (the questions and responses are detailed in Enclosure 2) which will be submitted formally to the NRC as part of

the license amendment review. The licensee's response to Question 4 regarding how many

missile types can be used in the TORMIS methodology was sufficient, and does not need to be

included in the licensee's formal response.

The NRC staff requested the licensee to provide a description of how the tumbling of missiles was accounted for in the analysis and why they used a 1 foot increase in each free surface

instead of the TORMIS standard of length of the free surface divided by eight (response to

Question 5). The licensee explained their modeling assumptions and agreed that the formal

response would include more detail. The licensee discussed their proposed response to Question 6 (of Enclosure 2), related to impact velocity thresholds used to calculate crush probabilities of the exposed equipment. The

NRC staff explained that this approach will require detailed description of their finite element

analysis and calculations of the impact velocities, which will need to be reviewed by the NRC

staff.The NRC staff asked the licensee why they assumed the Tubine Building walls are capable of providing tornado missile protection during an F1 or F2 tornado (Question 7). The NRC staff

stated that this assumption would require further justification. The licensee explained the

conservatisms in their turbine building analysis, and agreed to either do additional modeling, where the turbine building walls failed during F1 and F2 grade tornadoes, or provide additional

information to justify why excluding F1 and F2 tornadoes is reasonable.

In addition, the licensee stated that they will provide additional information of their missile survey efforts, including standardized tables used to estimate the number of source missiles per

square foot for several structures; as well as the most recent measures taken to minimize the

number of potential missiles at the site.

Members of the public were in attendance. Public Meeting Feedback forms were not received.

Please direct any inquiries to me at 301-415-3733, or rfk@nrc.gov.

/RA/Robert F. Kuntz, Project Manager Plant Licensing Branch III-2

Division of Operating Reactor Licensing

Office of Nuclear Reactor Regulation Docket No. 50-305

Enclosures:

1. List of Attendees

2. Licensee Handout cc w/encls: See next page The licensee discussed their proposed response to Question 6 (of Enclosure 2), related to impact velocity thresholds used to calculate crush probabilities of the exposed equipment. The