ML20237J862

Forwards Request for Addl Info Re Snupps Main Steam Line Break Outside Containment W/Superheated Steam Release Analysis in Order to Continue Review of Util 860404 & 870401 Submittals.Response Requested within 45 Days

ML20237J862
Person / Time
Site:	Wolf Creek
Issue date:	08/18/1987
From:	Oconnor P Office of Nuclear Reactor Regulation
To:	Withers B WOLF CREEK NUCLEAR OPERATING CORP.
References
TAC-61224, NUDOCS 8708260345
Download: ML20237J862 (4)

Text

f August 18, 1987 1

Docket No. 50-482

! Mr. Bart D. Withers l President and Chief Executive Officer Wolf Creek Nuclear Operating Corporation Post Office Box 411 Burlington, Kansas 66839

Dear Mr. Withers:

i l

SUBJECT:

REQUEST FOR ADDITIONAL INFORMATION RELATED TO THE SNUPPS MAIN STEAM LINE BREAK OUTSIDE CONTAINMENT WITH SUPERHEATED STEAM RELEASE ANALYSIS (TAC 61224) l The staff is continuing its review of your submittals dated April 4, 1986 I and April 1, 1987. To permit us to continue our review on our current schedule, we require the information requested in the enclosure to this letter be provided.

Please provide the requested information within 45 days of your receipt of this letter.

The reporting and/or recordkeeping requirements contained in this letter affect fewer than ten respondents; therefore, OMB clearance is not required under P.L.96-511.

Sincerely, Is)

Paul W. O'Connor, Project Manager Project Directorate - IV Division of. Reactor Projects - III, IV, V and Special Projects

Enclosure:

As stated cc w/ enclosure:

See next page DISTRIBUTION V1stket File NRC PDR Local PDR PD4 Reading F. Schroeder P. Noonan P. O'Connor OGC-Bethesda E. Jordan J. Partlow ACRS (10) PD4 Plant File LTR NAME: LETTER TO BART D. WITHERS PD4/LA PD4/PMf PD4/D M' PNoona P0Connor:sr JCalvo 8//3/87 8/A/87 8//y/87 8708260345 870810 PDR ADOCK 05000402 P PDR

l

. Mr-' Bart D. Withers Wolf Creek Geneiating Station Wolf Creek Nuclear Operating Corporation Unit No. I cc:

Jay Silberg, Esq. Mr. Gerald Allen l Shaw, Pittman, Potts & Trowbridge Public Health Physicist 1800 M Street, NW Bureau of Air Quality & Radiation Washington, D.C. 20036 Control Division of Environment Chris R. Rogers, P.E. Kansas Department of Health Manager, Electric Department and Environment Public Service Commission Forbes Field Building 321 P. O. Box 360 Topeka, Kansas 66620 Jefferson City, Missouri 65102 Mr. Gary Boyer, Plant Manager Regional Administrator, Region III Wolf Creek Nuclear Operating Corp.

U.S. Nuclear Regulatory Commission P. O. Box 411 799 Roosevelt Road Burlington, Kansas 66839 Glen Ellyn, Illinois 60137 Regional Administrator, Region IV Senior Resident Inspector / Wolf Creek U.S. Nuclear Regulatory Commission c/o V. S. Nuclear Regulatory Commission Office of Executive Director P. O. Box 311 for Operations . 1 Burlington, Kansas 66839 611 Ryan Plaza Drive, Suite 1000 l Arlington, Texas 76011  !

Mr. Robert Elliot, Chief Engineer  ;

Utilities Division Mr. Otto Maynard, Manager Licensing l Kansas Corporation Commission Wolf Creek Nuclear Operating Corp.  !'

4th Floor - State Office Building P. O. Box 411 Topeka, Kansas 66612-1571 Burlington, Kansas 66839 i

t i

4  ?

i

- ENCLOSURE

1. For all instances where the qualification temperatures of various pieces of equipment (e.g., Main Steam Pressure Transmitter, Main Steam Isolation Valve, etc.) may be exceeded as a result of a design basis accident and you have determined that alternate equipment is l available to accomplish the function of the failed equipment,  ;

discuss the environmental qualification status of the alternate '

equipment.

la. Is the criteria for using the alternate equipment contained in the plant emergency operating procedures?

2. In your evaluation, it is stated that the Main Steam Isolation Valves and the Main Feedwater Isolation Valves are both qualified to a temperature of 450 F; however, the appurtenances have various quali-fic6 tion temperatures. Our review has found that some of these quali-fication temperatures, are as low as 300 F. Note that the staff considers the qualification status of any piece of equipment to be based on its weak link. Please explain why you consider this item to be qualified to 450 F when some of its appurtenances are qualified to temperatures less than 450 F (e.g., Terminal Blocks 300 F, limit Switch 342, Wiring 346 F, Terminal Lugs 352 F and Conax Seals 420 F).

3. Explain why the (XLPE) Control Cable, identified in'your submittal

) as qualified to 385 F, is expected to perform its function when its

) qualification temperature is exceeded.

4. In the submittal provided by letter dated April 1, 1987, you have compared various equipment items to establish similarity. Although all items may be similar as you have stated, you did not always )

provide sufficient information for a reviewer to reach that J conclusion (e.g. , on page 6 of 27 it is stated, in part, that a thermal lag curve was not specifically developed for a limit switch).

It was assumed that a limit switch housing thermal response would be si.ilar to the response of the solenoid valve solenoid housing (Equipment 1). It is further stated that this assumption is appropriate because the thickness of the limit switch body is equal i to the molded solenoid valve solenoid housing. Ycu also. referred '

the reader to a sketch.

For Equipment 1 (solenoid housing), you have provided some detail information that is appropriate for comparison purposes such as the fabrication material of the housing, density, thermal conductivity, i specific heat, thickness and a sketch. However, similar information was not provided for the limit switch.

Consequently, for all instances where you have made comparisons similar to the above examples, you must provide all information necessary to reach an independent conclusion (i.e.. information such as that provided for Equipment 1 in the above example).

.l 1

i

I

)

5. In accordance with IEEE Standard _323-1974, a margin of 15 F is I I

required when qualifying lfor temperature in a harsh environment.

According to information provided for MSIV/MFIV control cable and MSIV/MFIV wiring and' lugs, margins of only 2*F and 6*F respectively, are indicated. Discuss the rationale' for your determination that this is acceptable.

6. The-analysis conducted for main stream line break with superheat indicated that the qualification temperatures of. four items of

-equipment will be exceeded, and an additional two items (identified in question 5 above) does not need the margin requirement of IEEE 323-1974. These six items are identified in Table 3.4 of your submittal as:

1. Main Steam Pressure Transmitter Instrument Cable

2. MSIV/MFIV Wiring and Lugs

3. MSIV/MFIV Control Cable

4. MSIV/MFIV Limit Switch

5. MSIV/MFIV Limit Switch Instrument Cable

6. J-601A Control Cable Discuss the consequences of the simultaneous failure of all six items.

l j

2 j

i l

1

_ - _ _ - - _ _ _ .