ML20214U735

Identifies Addl Info Required in Order to Determine Acceptability of Alternative Shutdown Panel Design Installed in Plant,Per Util 861014 Commitments in FSAR Re Reg Guide 1.68 & 10CFR50,App R

ML20214U735
Person / Time
Site:	Fermi
Issue date:	11/21/1986
From:	Adensam E Office of Nuclear Reactor Regulation
To:	Sylvia B DETROIT EDISON CO.
References
RTR-REGGD-01.068, RTR-REGGD-1.068 NUDOCS 8612090377
Download: ML20214U735 (4)

Text

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November 21, 1986-DISTRIBUTION:

46341p Docket No. 50-341 BWD-3 r/f R8ernero EAdensam JPartlow EHylton EJordan Mr. B. Ralph Sylvia _ JStefano BGrimes Group Vice President - Nuclear Operations Glainas ACRS (101 Detroit Edison Company JHulman a g c._ /42 6400 North Dixie Highway KCampe Locu/

Newport, Michigan 48166 JRidgely CWoodhead (0GC) p g -

Subject:

Fermi-2 Operating Licensing No. NPF-43, license Condition 2.C(9)(b) 10 CFR 50, Appendix R, Paragraph III.L., " Alternative and Dedicated Shutdown capability" My letter to DECO dated August 19, 1986, submitted the staff's draft SER which was' predicated on information furnished by DECO letters dated September 27, 1985, July 15, 1986, and August 15, 1986, in response to the subject license condition.

Mr. F. E. Agosti's letter to me dated October 14, 1986, responding to the staff's draft SER, has been reviewed. 'The staff identified a need for still further information in order to determine the acceptability of the alternative shutdown-panel design installed in the Fermi-2 plant pursuant to DECO commitments in the FSAR relative to Regulatory Guide 1.68:

a. The enclosure to the October 14, 1986, DECO letter, bottom of page 3, references an October 22, 1984, letter, which stated that an analysis performed by DECO shows that over 20 minutes is available before operator action is required to mitigate the transient for reactor isolation events with no feedwater or ECCS initiation. The draft FSAR Figure 9B-25 pro-vided in the October 22, 1984, letter, shows that the reactor water level is at the top of the active fuel 20 minutes into the event. Appendix R, Paragraph III.L.1 (10 CFR 50) states that, "During the postfire shutdown, the reactor coolant system process variables shall be maintained within those predicted for a loss of normal a.c. power....." Paragraph III.L.2.b states that, "The reactor coolant makeup function shall be capable of maintaining the reactor coolant level above the top of the core...."

The infomation provided with the October 22, 1984, letter does not i clurly describe how the top of the active core will not be uncovered when makeup water is not initiated for the first 20 minutes. It is,

! accordingly, requested that DECO provide a supplemental analysis which demonstrates compatibility with the above cited paragraphs of Appendix R, without the initiation of makeup water for 20 minutes, in order for the i staff to understand the degree of margin which exists in the Fermi-2 design.

b. The second paragraph on page 2 of the enclosure to the October 14, 1986, letter states in part that, "This testing [of the III.L panel] included actual verification of transferring control, of the affected components, from the control room to the 3L Panel and various local shutdown panels.

Each component was operated from its respective shutdown panel and veri-fied that the control of the panel could not be overridden by the Control Room." The question is: what protection is provided to prevent the III.L panel from overriding control room signals?

! 8612090377 861121 gDR ADOCK0500g1

c. In conjunction with item a. above, DECO calculated that 20 minutes will be available to power the III.L panel to provide makeup water to the reactor vessel in the event of a fire; and that tests conducted by DECO have determined that the III.L panel can be successfully powered for this purpose within 13 minutes. As stated in the last paragraph on page 2 of the enclosure to the October 14, 1986, letter, the operator will scram the reactor, isolate the CTG #1 power supply " designated" as the power source for the III.L panel, and isolate the SBFWS before leaving the control room. These multiple actions appear to presuppose the location and growth of the fire, an assumption for which credit has not been previously given by the staff in evaluating a plant's compliance with fire protection requirements. The 13 minute time period was deter-mined by having CTG #1 on line, by opening the output breaker, and by re-starting CTG #1 to verify its ability to reject load and to restart and supply power to the III.L panel. In order to ascertain that there will be sufficient margin to ensure makeup water to '.he reactor vessel within the 20 minutes calculated by DECO, it is requested that DECO consider the effects of the time required to initiate makeup water to the reactor vessel by not isolating CTG #1 and the SBFWS until after the' operator leaves the control room, with the fire initiating in the CTG #1 and SBFWS control room panels, and considering the resultant spurious operation and shorting of those panel circuits due to the fire.

Also verify that no damage will result to the III.L panel and shutdown components, that adequate water will be provided to safely shutdown the reactor, and that makeup water to the reactor vessel can still be initi-ated well within the 20 minutes calculated from fire onset.

d. DECO intends to use CTG #1 as the " designated' power supply source for the III.L panel. The staff's draft SER, submitted by letter dated August 19, 1986, specifies that a " dedicated" power supply be provided for the III.L panel. -The staff is not certain whether the " designated" power supply adequately meets the guidelines of Regulatory Guide 1.68 as committed to by DECO in the FSAR. In the third paragraph on page 3 of the enclosure to the October 14, 1986, letter, it is stated that tests have demonstrated that the CTG #1 power supply, " designated" to provide power to the III.L panel, can be tripped (assuming it is being operated to provide peak power at time of the fire), and that power can be provided to the III.L panel to initiate makeup water to the reactor vessel within 13 minutes. In addition to the information requested under item c. above, DECO is requested to provide a breakdown of the time re-quired from onset of the fire until makeup water is supplied to the reactor vessel, assuming that CTG #1 is not tripped until the operator gets to the III.L panel. If CTG #1 trips off-line when it is trying to pick up III.L panel loads, indicate the time required to restart CTG #1, to power the III.L panel, and to begin supplying makeup water. In so doing, address what alternative power supply source (s), equipment oper-ations, procedures, etc. have been considered to get water to the reactor vessel within the 20 minutes calculated to avoid core uncovery.

e -. .

Mr. B. Ralph Sylvia Detroit Edison Company Fermi-2 Facility cc:

Mr. Harry H. Voigt, Esq. Ronald C. Callen.

LeBoeuf, Lamb, Leiby & MacRae Adv. Planning Review Section 1333 New Hampshire Avenue, N. W. Michigan Public Service Commission Washington, D. C. 20036 6545 Mercantile Way P. O. Box 30221 John Flynn, Esq. Lansing, Michigan 48909 Senior Attorney The Detroit Edison Company Regional Administrator, Region III 2000 Second Avenue U. S. Nuclear Regulatory Commission Detroit, Michigan 48226 799 Roosevelt Road Glen Ellyn, Illinois 60137 Mr. Dennis R. Hahn, Chief Nuclear Facilities and Environmental Monitoring Section Office Division of Radiological Health P. O. Box 30035 Lansing, Michigan 48909 Mr. Robert Woolley Acting Supervisor-Licensino The Detroit Edison Company Fermi Unit 2 6400 No. Dixie Highway Newport, Michigan 48166 Mr. Walt Rogers U. S. Nuclear Regulatory Commission Resident Inspector's Office 6450 W. Dixie Highway Newport, Michigan 48166 Monroe County Office of Civil Preparedness 963 South Raisinville Monroe, Michigan 48161 36

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If. there are any questions or clarifications relative to this request, please have your staff advise the Project Manager, John J. Stefano, accordingly.

Sincerely, Elinor G. Adensam, Director BWR Project Directorate No. 3 Division of BWR Licensing cc: See next page BWD-3: DBL g DI3: DBL P D. D [ DBL JStefano/vaa

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