ML20216F903

Responds to 980305 RAI Re Withdrawal of Commitment Related to TN-40 Cask Fabrication

ML20216F903
Person / Time
Site:	Prairie Island
Issue date:	04/13/1998
From:	Sorensen J NORTHERN STATES POWER CO.
To:	NRC OFFICE OF INFORMATION RESOURCES MANAGEMENT (IRM)
References
72-0010-94-212, 72-10-94-212, NUDOCS 9804170274
Download: ML20216F903 (5)

Text

1 Northern States Power Company Prairio Island Nuclear Generating Plant 1717 Wakonade Dr. East Welch, Minnesota 55089 l

l l April 13,1998 l l

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l U S Nuclear Regulatory Commission l Attn: Document Control Desk Washington, DC 20555 PRAIRIE ISLAND INDEPENDENT SPENT FUEL STORAGE INSTALLATION Docket No. 72-10 l

Materials License No. SNM-2506 l

l Response to Request for Additional Information With Regard to l Withdrawal of Commitment Related to TN-40 Cask Fabrication l By letter dated December 1C,1997, Northern States Power informed the NRC Staff of our withdrawal of the commitment that a representative from Northern States Power Company or Transnuclear would be present at all future TN-40 cask resin pours to l monitor the process and review resin pour data sheets. In a letter dated March 5, 1998, the NRC Staff requested additional information related to the withdrawal of the subject commitment so that they could evaluate the request to delete the NSP vendor oversight commitment for TN-40 fabrication activities at the new vendor. The NRC Staff also requested clarification of the level and scope of the NSP TN-40 fabrication vendor oversight program. The response to the March 5,1998 NRC request for additional information is attached.

In this letter we have made no new Nuclear Regulatory Commission commitments.

I If ycu have any additional questions related to the attached information, please contact Gene Eckholt (612-388-1121).

/ . r % --

Joel P. Sorensen  ;

Plant Manager l Prairie Island Nuclear Generating Plant 9804170274 980413 PDR ADOCK 05000202 f( PDR

F USNRc NORTHERN STATES POWER COMPANY April 13, 1998 Page 2 t .

I l c: Director, Spent Fuel Project Office

! NMSS Project Manager, NRC Regional Administrator - Region Ill, NRC l Senior Resident inspector, NRC l NRR Project Manager, NRC J E Silberg i Prairie Island independent Spent Fuel Storage Installation Service List I

Attachment:

Response to Request for Additional Information With Regard to Withdrawal of Commitment Related to TN-40 Cask Fabrication l

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i l Response to Request for Additional Information With Regard to Withdrawal of Commitment Related to TN-40 Cask Fabrication History The NSP commitment to be present at all future resin pours to monitor the process and I review resin pour data sheets was made in response to NRC Inspection Report No. 72-10/94-212. Specifically, violation B.1 stated; B. 10CFR 72.152, " Document control," requires the licensee to establish measures to ensure that documents, including changes, are reviewed for adequacy, approved for release by authorized personnel, and distributed and used at the location where the prescribed activity is performed, Contrary to the above;

1. Procedure No. RI-1103, " Resin Installation Procedure," and its associated data record sheets were not revised to reflect a change in the fabrication process. l The NSP response identified two actions to avoid further violations.

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1. A formal temporary procedure change process for the project was incorporated. '

PXE personnel were trained on the new process.

2. NSP committed that a representative from Northern States Power or Transnuclear would be present at all future resin pours to monitor the process and review resin pour data sheets.

The violation resulted from a situation where the previous cask fabricator, PX Engineering (PXE) was unable to achieve the initial cask temperature conditions as required by the resin pouring procedure. As the PXE QA program did not have a formal temporary procedure change process, there was no way to bring the cask to the desired initial conditions without interrupting the process. While proper engineering guidance was obtained and documented by Transnuclear altering the process to account for the differing conditions, the procedure and associated data sheets were not revised until after the resin pour was completed. The PXE QA program was subsequently revised to include a formal temporary procedure change process.

l There are several differences between PXE and PCC that justify the deletion of the l commitment to monitor all future resin pours at a 100% level.

. PCC has extensive experience fabricating similar casks using the same resin compound. To date,12 casks have been fabricated using this same neutron shielding resin.

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,e PCC has more extensive climate control facilities to achieve the desired initial conditions at the time of resin pouring. PXE had limited climate control facilities for resin pouring and therefore had more difficulty achieving the required initial conditions.

. The issue with the initial cask resin pouring was not that the resin was poured in a manner that adversely affected the quality of the final product, but rather that the required change to the procedure was not implemented until after the completion of j resin pouring activities.

i Specific NRC Questions The March 5,1998 letter from Susan Shankman (NRC) to Joel Sorenson (NSP) specifically requested the following information.

"However, you did not indicate whether NSP had performed a vendor qualification audit of this new vendor and assessed the resin pour capabilities and quality control of fabrication processes for adequacy."

NSP performed a full scope QA audit of the new fabricator, Precision Components Corporation (PCC) of York, PA, in April 1997. This audit was a qualification audit of the fabricator in anticipation of placing an order with Transnuclear for 5 additional TN-40 casks. The PCC QA program was determined to be in compliance with the applicable requirements and effectively implemented. PCC was added as an approved supplier i on the NSP operational Quality Assurance Vendors List for the fabrication of dry spent l fuel storage casks.  ?

In addition to the NSP qualification audit, PCC has been audited by Transnuclear and  ;

is an approved supplier of Transnuclear.

l The PCC fabrication QA program has been recently audited twice by the NRC, once in l

June,1996 (Inspection Report No. 72-0002/96-203) and again in April 1997 (Inspection i Report No. 72-0002/97-208). No violations were noted in either of these reports. The June,1996 audit included a specific review of selected resin pouring operations (Section 2.3.2, ' Fabrication and Assembly', pg.10-11).

" you did not indicate what level of NSP oversight will be actually implemented."

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NSP Mtablished a QAIOC oversight plan prior to the start of fabrication. An overview of this plan was presented to the NRC in July,1997. As part of that plan, a full time NSP representative was located at the fabrication facility beginning in October 1997.

t This representative is augmented by additional NSP resources on an as-needed basis, both by NSP QA/QC personnel and also project engineering. Surveillance areas include pre-established hold / witness / notification points, as well as selected on-going l

activities as they occur.

NSP only intends to withdraw the commitment to monitor 100 % of all resin pouring activities.. Monitoring of resin pouring, along with other fabrication activities, will l continue to occur on a frequency determined by the NSP Project Manager for Dry Cask l Quality Assurance.

l l "In addition, please clarify the level and scope of the NSP TN-40 fabrication vendor oversight program."

! As noted above, NSP has a full time representative located in the fabrication shop.

l This representative is augmented by additional NSP resources on an as-needed basis, both by NSP QA/QC personnel and also project engineering.

NSP oversight of vendor fabrication includes many areas in addition to physical inspections at the shop. Some of these additional activities include; NSP review of shop submittals include:

• Shop drawings

. Weld procedures

. NDE procedures

. Test procedures

. All safety related and augmented quality related purchase orders

. Review and approval of all NCR dispositions

. Review and approval of all radiographs Summary It is NSP's intention to continue to monitor resin pouring operations at PCC as with all special processes for the TN-40. The removal of the commitment to monitor 100% of all resin operations will allow NSP to concentrate oversight resources where they will be most effective. The level of oversight for all activities is determined by several consideratior.s, including vendor performance and the impact of activity on the safety of the cask.

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