ML20055A332

Responds to 820707 Telcon & Submits Addl Info Re Code Relief Request 3 on Inservice Insp

ML20055A332
Person / Time
Site:	Davis Besse
Issue date:	07/12/1982
From:	Crouse R TOLEDO EDISON CO.
To:	Stolz J Office of Nuclear Reactor Regulation
References
838, NUDOCS 8207160163
Download: ML20055A332 (3)

Text

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e O TOLEDO

%mm EDISON Romp.C m Docket No. 50-346 w. p -

%cies License No. NPF-3

• S'2 " 3' Serial No. 838 July 12, 1982 Director of Nuc1 car Reactor Regulation Attention: Mr. John F. Stolz Operating Reactor Branch No. 4 Division of Operating Reactors United States Nuclear Regulatory Commission Washington, D.C. 20555

Dear Mr. Stolz:

Our letter dated June 22, 1982 (Serial 830) transmitted a Code Relief Request for the Davis-Besse Nuclear Power Station Unit No. 1. Per a conference call on July 7, 1982 between members of your staff and Toledo Edison personnel, additional information was requestca. These items are listed and a response provided in the attachment to this letter.

Very truly yours,

[

RPC:LDY: lab attachment ec: DB-1 NRC Resident Inspector M. R. Hum, NRC NRR i l

hovi THE TOLEDO EDISON COMPANY EDISON PLAZA 300 MADISON AVENUE TOLEDO OHIO 43652 8207160163 820714 PDR ADOCK 05000346 G PDR

o DAVIS-BESSE UNIT NO. 1 DOCKET No. 50-346 INSERVICE INSPECTION SECTION Request For Additional Information Regarding Relief Request No. 3

1.

Reference:

Drawing HL-1155.

Confirm that no flanged connections are contained in the runs of pipe from FW 37 to FW 30 and FW 45 to FW 38 (existing pipe to inlet of the ring header) that can be used to isolate the new piping system.

Response: The above runs of pipe have all welded connections with no flanges that could be used for isolation purposes. I

2.

Reference:

TECO leter Serial No. 830, Attachment 1.

A. Define the specific temperature at which the proposed System Reduced Pressure Hydrostatic Test will be performed.

(Paragraph 5.A)

Response: The nozzle into the steam generator will be at approximately 530*F with a thermal gradient down to approximately 185'F into the Auxiliary Feedwater (AFW) header. The piping leading up to the AFW header will remain.at an ambient AFW water temper-ature of approximately 90*F.

B. Define the specific Code nondestructive and augmented examination that will be performed on the 94 additional welds.

(Paragraph 6.A.)

Response: Installation inspection of the new welds will be radiographed and surface examined per the requirements of Section III of the ASME Code 1977 Edition through Summer 1978 addenda. Baseline inspection will be performed on welds and supports per ASME Section XI IWC-2500. In addition, 10% of the welds under 4" in diameter will be augmented inspected when the sum of equations 9 and 10 in NC-3652 exceed 0.8 (1.2S S . Also, the entire pipingsystemispresentky+in$)udedinthetenyear l

ISI hydrostatic test plan.

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3.

Reference:

TECO letter Serial No. 830, Attachment 1.

What personnel exposure will be received as a result of doing thL inspection if relief is granted; if relief is not granted; and '; ort the overall Auxiliary Feedwater repair / replacement ef fort. '

Response: Based on doing the proposed reduced pressure test, no {

additional exposure to personnel to do the-walkdown is j anticipated since the walkdown requirement exists

irrespective of the reduced pressure test. The .

man-rem exposure from doing the code hydrostatic '

test is estimated to be approximately five man-rem total exposure. This was conservatively estimated from current radiation exposure readings in the areas of concern.

The overall exposure to do the AFW header repair / replace- -- (

ment work will result in approximately 10 to 20 man-rem ' '

exposure. The steam generator tube plugging portion of the effort will result in an exposure of approximately 5 to 6 man-rem. These values are rough estimates as work is still underway but are our best estimates to date, d/3

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