ML20207G528

Ack Receipt of Expressing Concern for Reactor Core Shroud for Plant,Unit 1.NRC Staff Requested to Conduct Insp of Reactor Shroud,Including Areas Outside Core Shroud Welds & Publicly Disclose Results 1 Wk Before Plant Restart

ML20207G528
Person / Time
Site:	Nine Mile Point
Issue date:	06/09/1999
From:	Hood D NRC (Affiliation Not Assigned)
To:	Chiquoine I AFFILIATION NOT ASSIGNED
References
NUDOCS 9906110195
Download: ML20207G528 (3)

Text

50 ~220 pf'%g g

1 UNITED STATES NUCLEAR REGULATORY COMMISSION WASHINGTON, D.C. 200000001 June 9,1999 Ms~. Isabel Chiquoine 31 Noston Ave.

Clinton, NY 13323

Dear Ms. Chiquoine:

In a letter to me dated May 16,1999, you expressed concem for the reactor core shroud at Nine Mile Plant Nuclear Station, Unit No.1 (NMP1). You requested that the U.S. Nuclear Regulatory Commission (NRC) staff conduct its own inspection of the reactor shroud, including areas outside the core shroud welds, and publicly disclose the results at least a week before the plant's restart date.

Ci..N the date of your letter, the licensee has completed the reinspection of the shroud and has repaire>:! the two shroud vertical welds (V9 and V10) that have significant cracks. The repair used special clamps bat the NRC approved by letter dated April 30,1999. The repair clamps structurally restore the design bases for the vertical welds. The licensee has verbally informed the NRC staff that the reinspection of other vertical welds during the current refueling outage indicates that repairs are not needed. The shroud horizontal welds were structurally replaced by four tie-rod assemblies that were installed in 1995 due to extensive cracking. The licensee has verbally informed the NRC staff that, based upon the inspec* ions during the current outage, the tie rods are satisfactorily performing their intended function of maintaining a predetermined compressive force ("preload") on the shroud during power operation. During the current outage, the licensee also made minor repairs, authorized by the NRC, to ensure the successful performance of springs that are part of the tie rod assemblies.

The licensee has also verbally informed us that, during the current outage, ultrasonic examinations wars performed in the accessible areas of base metal 12 to 18 inches along either side of shroud vertical welds V9 and V10. These inspections were performed voluntarily by the licensee as no NRC regulation or industry standard requires the lospection of the base metal.

As a regulator in accordance with the Atomic Energy Act, as amended, the NRC does not perform the actual examinations of the reactor vesselintemals; rather, this is the responsibility of each licensee. NRC inspectors have monitored the licensee's shroud reinspection and repair

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activities at NMP1 during the current refueling outage. Their observations indicate that the licensee has followed the reinspection plan that the NRC approved March 24,1999, before the O

4 outage began. An NRC inspection report will be issued in the near future. The licensee's reinspection results and the licensee's analysis to disposition these reinspection findings are required to be submitted to the NRC within 30 days of completing the reinspection and will be 4DI made publicly available. Therefore, the licensee's inspection results cannot be made available

~g to you before the plant restarts.

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1. Chiquoine Thank you for sharing your concems with the NRC. I trust this reply has been responsive to the concems in your letter.

Sincerely,

~ h)hhr, Darl S. Hood, Sr. Project Manager, Section i Project Directorate i Division of Licensing Project Management Office of Nuclear Reactor Regulation 1

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1. Chiquoine Thank you for sharing your concerns with the NRC. I trust this reply has been responsive to the concerns in your letter.

Sincerely, Original signed by:

Darl S. Hood, Sr. Project Manager, Section i Project Directorate l Division of Licensing Project Management Office of Nuclear Reactor Regulation DISTRIBUTION:

Docket File 4:

PUBLIC PD l-1 R/F S. Bajwa S. Little

' D. Hood OGC ACRS M. Oprendek, Region I l

D. Screnci, Region l W. Bateman E. Imbro i

DOCUMENT NAME: G:\\PDI-1\\NMP1\\CHlOUOINE.WPD To receive a copy of this document, Indicate in the box: "C" = Copy without attachment / enclosure "E" = Copy j

with rttachment/ enclosure "N" = No copy i

0FFICE PM:PDI-1 lE LA:PDI-ljiO l

DADl-)f j.

l l

l NAME DHood/rsl, D 3 [/

Slittl F 6678/ f DATE 06/ 4 /99 06/4 /99 06/t /99 '

06/ /99 06/ /99 Official Record Copy 1

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