ML071500106

Another Key Assumption for the Possible Completion of Construction Activities

ML071500106
Person / Time
Site:	Watts Bar
Issue date:	05/17/2007
From:	Lochbaum D Union of Concerned Scientists
To:	Document Control Desk, NRC/NRR/ADRO
References
Download: ML071500106 (3)

Text

Union of

.. Concerned Scientists Citizens and Scientists for Environmental Solutions May 17, 2007 U.S. Nuclear Regulatory Commission ATTN: Document Control Desk Mail Stop: OWFN P1-35 Washington, DC 20555-0001 In the Matter of ) Docket No. 50-391 Tennessee Valley Authority )

SUBJECT:

WATTS BAR NUCLEAR PLANT (WBN) - UNIT 2 - ANOTHER KEY ASSUMPTION FOR THE POSSIBLE COMPLETION OF CONSTRUCTION ACTIVITIES

Reference:

TVA letter dated April 3, 2007, Preston D. Swafford, Interim Chief Nuclear Officer, to NRC, "Watts Buar Nuclear Plant (WBN) - Unit 2 - Key Assumptions for the Possible Completion of Construction Activities."

Dear Mr. or Ms. Desk:

The Tennessee Valley Authority (TVA) sent you the referenced letter seeking feedback from the Nuclear Regulatory Commission (NRC) on two licensing assumptions in its decision-making process about Watts Bar Unit 2. In reviewing that letter, one equally key assumption appears missing.

As TVA mentions, the NRC licensed Watts Bar Unit 1 in 1996. It is more than a decade later and TVA may seek a -license from NRC for Watts Barr Unit 2. The missing. key assumption involves that significant time gap, the decade-plus between the licensing of Unit 1 and the potential licensing of Unit 2.

If licensed, Watts Bar Unit 2. would share common equipment with Watts Bar Unit 1. For example, both units would rely on common offsite and onsite power systems, essential service water systems component cooling water system, and common area ventilation systems. Since being licensed by the NRC in 1996, Watts Bar Unit 1 has operated and used up a considerable chunk of the useful life of the common equipment and systems.

Because Watts Bar Unit 1 is more than ten years older than her Unit 2 "twin sister," it seems necessary to identify a licensing assumption relative to this common equipment. In other words, would the license term for Watts Bar Unit 2 be 40 years minus the time accrued on the common equipment and systems that.

Unit 1 has used up, a full 40 years based on some license renewal styled aging management review for the common equipment and systems, or some other duration? The term of the license and its associated conditions seem very relevant to the scope of homework necessary for Watts Bar Unit 2.

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May 17, 2007 Page 2 of 2 In their letter, TVA sought NRC's feedback on their key licensing assumptions. If you concur with our view on the shared systems issue, please include it in the feedback you provide TVA.

Sincerely, David Lochbaum Director, Nuclear Safety Project

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