ML13183A226

G20130462/LTR-13-0528 - Letter to Senator Debbie Stabenow, from: R. W. Borchardt, Constituent Concerns Regarding Repairs at Palisades

ML13183A226
Person / Time
Site:	Palisades
Issue date:	07/03/2013
From:	Borchardt R NRC/EDO
To:	Stabenow D US SEN (Senate)
Rihm R, 415-1717
Shared Package
ML13169A231	List: ML13169A229 ML13169A232 ML13183A226
References
G20130462
Download: ML13183A226 (3)

Text

July 3, 2013 The Honorable Debbie Stabenow United States Senator 3280 Beltline Court, Suite 400 Grand Rapids, MI 49525

Dear Senator Stabenow:

On behalf of the U.S. Nuclear Regulatory Commission (NRC), I am responding to your letter of June 18, 2013, forwarding a copy of an email from your constituent, Kathy Barnes, regarding the Palisades Nuclear Plant. Ms. Barnes questioned both recent repairs following leakage from the safety injection refueling water tank (SIRWT) and the overall safety of the facility. The NRC Region III Public Affairs Officer responded to her email on June 14, 2013. This response provides additional information.

Palisades was shut down on May 5, 2013, in response to leakage from the SIRWT of 90 gallons per day. This exceeded a leak rate limit of 38 gallons per day established in an NRC confirmatory action letter issued July 17, 2012, following earlier leakage.

The licensees repair activities in response to the most recent leakage included replacing most of the tank plating at the bottom of the SIRWT. While removing the old plates, the licensee inspected the underlying area and discovered that the as-built structure did not match the submitted design drawings. Specifically, the tank was constructed directly on the concrete slab foundation without a sand bed to provide a cushion for the tank bottom. Also, there was no evidence of any coating between the concrete and the bottom aluminum plates. The NRC currently is reviewing why the as-built structure did not match the design drawings.

As a result of these discoveries, the licensee installed a layer of asphalt-impregnated fiberboard to provide the necessary separation between the aluminum tank and the concrete and to cushion the tank bottom. This action was consistent with the original construction code document, which recommended the use of this type of fiberboard over the concrete ring wall in order to protect aluminum plates from localized stresses and corrosion. The asphalt-impregnated fiberboard is intended to be used in contact with the ground and be water resistant over the anticipated life of the concrete structure. The licensee confirmed that the fiberboard is permanent, is not required to be replaced, and was manufactured in accordance with the applicable American Society for Testing and Materials (ASTM) standard. In addition to our resident inspectors, NRC specialists in metallurgy and engineering requirements reviewed the repair plans and monitored major tank repair activities. The Palisades plant resumed operation on June 17, 2013, after the repairs were completed.

We understand the plant has had a number of unplanned shutdowns recently. In an effort to inform the public and answer questions, the NRC has held public meetings and live Web discussions (Webinars) for the community and others interested in the plant. I hope your constituent had an opportunity to participate with us in these events. Based on NRC inspections during and following SIRWT repair activities and discussions between the NRC and the licensee, the NRC believes that the SIRWT retains the structural integrity necessary to meet its intended safety function.

Please be assured that the NRC is providing close oversight of the Palisades Nuclear Plant, and it continues to operate safely. The agency expects the licensee to fully address any identified shortcomings, and the NRC will take whatever actions are necessary to ensure continuing safe operation of the facility. If you need additional information, please contact me or Rebecca Schmidt, Director of the Office of Congressional Affairs, at (301) 415-1776.

Sincerely,

/RA/

R. W. Borchardt Executive Director for Operations

Pkg. ML13169A231 OFFICE OEDO RIII OGC OCA EDO NAME RRihm JGiessner EWilliamson TRiley (via email) RWBorchardt (via email) (via email)

DATE 07/2/13 06/27/13 07/01/13 07/02/13 07/03/13