ML17321A697

Requests Extension of Environ Qualification Deadline for Certain Instrument Cables Routed Inside Containment Bldgs, Per 10CFR50.49(h).Justification for Continued Operation Encl

ML17321A697
Person / Time
Site:	Cook
Issue date:	06/28/1985
From:	Alexich M INDIANA MICHIGAN POWER CO. (FORMERLY INDIANA & MICHIG
To:	Harold Denton Office of Nuclear Reactor Regulation
References
AEP:NRC:0775U, AEP:NRC:775U, NUDOCS 8507020278
Download: ML17321A697 (10)

Text

r .

REGULATOR i FORMATION DISTRIBUTION S EM (RIDS)

ACCESSION NBR! 8507020278 DOC ~ DATE: 85/06/28 NOTARIZED:" NO DOCKET FACIL:50 315 Donal d C ~ Cook Nucl ear power Pl antg Uni t' g Indiana 8 05000315 50-316 Donald C ~ Cook Nuclear power Plantg Unit 2g Indiana 8 05000316 AUTH INANE>> AUTHOR AF F ILI A T I ON ALEXICHrM.P, Indiana 8 Michigan E'lectric Co, REC IP, NAME. RECIPIENT AFFILIATION DENTON2H.Ro Office of Nuclear Reactor Regulationi Director

SUBJECT:

Requestsextension of envi ron qualification deadline for certain instrument cables routed inside containment bldgsf pdr 10CFR50,06(h) Justific ation for continued ope'ration

~

encl.

DISTRIBUTION CODE! A048D COPIES RE CEIVED:LTR ENCL I SIZE' TITLE: OR/Licensing Submittal: Equi pment Qualification NOTES:" 05000315 OL:10/25/7>>

05000316 OL: 12/22/72 +0. O O g 7 RECIPIENT COPIES RECIPIENT COPIES ID CODE/NAME LTTR ENCL" ID CODE/NAME LTTR ENCL NRR ORB1 BC 12 0 WIGGINGTONg D 01 f f>>

INTERNAL: ACRS 15>> 8 8 ADM/LFMB 1 0 ELD/HDS3 12 1 1 ELD SHIELDSpW 1 1" GC 13 1 1 NRR KARSCHgR 1 NRR/DE/EaB 07 2 DIR 10 1 1 NRR/DSI/AEB 1 1 REG F IL 04 1 1.

RGN3 1 1 EXTERNAL: 24X 1 1 LPDR 03 2 2 NRC pDR 02 1 1 NSIC 05 1 1 TOTAL NUMBER OF COPIES REQUIRED: LTTR 26 ENCL 24

H t '

1 4" f 4

< Krw) ' 41

~ I ) 14

\

I'w

~ ~

)

) K'" ')') K

~ ~

1K') N <<)4)< Y)4 )K II,') fr IKT fl4~4l 44 K) 5'4) 14,,44444,41 ' K t 1

4 I II t w 4 f K' 4 Ir ~ I 1 ) ilk Ig ( ) 4

)K )>>K) I) ) ~ .)r f )K)a > I ), ~,),. t'4 )K,) .

g

~ <i )p 4 re))K" r)), ~

j" 3) f",Iw 444 T,I).) t

] li ')~

Il ) 'l Kg ) 11 r)

IN DIANA 8 M IC H I G AN ELEC TRI C COM PA N Y P.O. BOX 16631 COLUMBUS, OHIO 43216 June 28, 1985 AEP:NRC:0775U Donald C. Cook Nuclear Plant Unit Nos, 1 and 2 Docket Nos.. 50-315 and 50-316 .

License Nos. DPR-58 and DPR-74 INSTRUMENT CABLE SUBMERGENCE QUALIFICATION

~

h ~ " "h hh h ~

Mr. Harold R. -=Denton;-Director---

Office of-Nuclear-Reactor Regulation U. S, -Nuclear Regulatory Commission Washington, D. - C. 20555

Dear Mr. Denton:

h h

- - --This letter requests an extension of environmental qualification- deadline, pursuant to -10 CFR 50.49(h), for certain instrument cables =routed inside the Donald- C."Cook-='Nuolear-Plant- containment buildings. This= extension request speoifically applies to the submergence requirements for those cables-serving .

four (4) steam generator narrow range level differential pressure transmitters in each unit, i.e., BLP-112, -122, -132, and -142.

~

the design effort associated with the planned replacement"of these--

it

'uring transmitters, was discovered. that the -instrument cables are routed below the maximum containment flood elevation, although their terminal points (at the instruments and at the flood-up boxes) are above-this-elevation. While these oables have been satisfactorily tested independently for submergence and radiation- effects, they were not sequentially tested. Acoordingly; -we-cannot" be assured that the transmitters served by these cables will perform their long term post-accident monitoring function.

h* h

~ 'We -now propose .to relocate these cables above the maximum flood elevation as part of the effort associated with the replacement of the transmitters. The schedule for proposed corrective -actions would therefore include relocation of the Unit 1 cables during the ten-'ear outage presently .taking place, and= ~

relocation of the Unit"2 cables during the next refueling- outage .(currently-anticipated to begin on or before= November -30, -1985)-; -Pending completion of.

the oable .relocation work, the attached 'Justi.fication for Continued Operation (JCO)'applies- for Unit': The JCO also Justifies operation of Unit 1 prior to the ourrent ten-year outage;-

E.

"It is noted hthat the proposed JCO-has= beeh"reviewed by"the Plant Nuclear-Safety Review'ommittee (PNSRC).-and the Nuclear Safety-Design Review Committee (NSDRC). "Additionally, pursuant to 10 CFR 170.12(c), an application fee has been enclosed. of'150.00 8507020278 850b28 y$ <

PDR ADOCK 050003 5 PDR , g(l 0 l P

~ ~

~ ~

Mr. Harold R. Denton AEP:NRC:0775U This document has been prepared following Corporate procedures which incorporate a reasonable set of controls to ensure its accuracy and completeness prior to signature by the undersigned.

Very truly yours, M. P. Alexich

/

Vice President i'd@

MPA/dam Enclosures cc: John E. Dolan M. G. Smith, Jr. - D. C. Cook Plant R. C.. Callen G. Bruchmann G. Charnoff NRC Resident Inspector - D. C. Cook Plant s

I ~

gruff

~ 4 t 44 )0 4 y

~ ff ~

4 IN

~ ~ ~

.,4

ATTAC Equipment Desoription: Steam Generator Narrow Range Level Differential Pressure Transmitters and Assooiated Instrument Cable Equipment Manufacturers: ITT Barton (Transmitters); Samuel Moore, Boston Insulated Wire (Cables)

Equipment Model/Item Nos.: 764 (Transmitters); 3075 (Cables)

Plant Identification Nos.: BLP-112, -122, -132, and -142 (Transmitters);

8584CY-1, 8585CY-1, 8586CY-1, 8587CY-1, 8584CY-2, 8585CY-2, 8586CY-2, and 8587CY-2 (Cables)

Deficiency: Cable Submergenoe The steam generator narrow range level transmitters,(BLPs) perform two functions for the D. C. Cook Nuclear Plant, a short term trip function and a long term post-accident monitoring function.

With regard to the short term trip function, the BLPs must respond within 22.1 seconds into a Main Steam Line Break (MSLB). During this time period, the containment flood elevation will not rise above the minimum mounting elevation for any of the twelve (12) BLPs inside containment. It is therefore believed that the BLPs will be available to provide the necessary reactor protective function for the short term.

For the long term, the D. C. Cook Nuclear Plant Technical Specifications require at least one (1) available BLP per steam generator for post-accident monitoring purposes. In this capacity, the BLPs are considered a redundant indication of auxiliary feedwater flow, normally provided by four (4) transmitters located outside containment (FFI<<210, -220, -230, and -240). Here it is noted that the FFIs share a oommon, balance-of-plant power supply; however, neither the power supply nor the FFIs will be exposed to the same design basis accident (DBA) environment as the BLPs. Therefore the FFIs ar e expected to be available following the DBA.

r In summary, it is believed that the minimum necessary post-aocident auxiliary feedwater flow monitoring funotion will be available following a DBA. This is supported by the following:

The cables in question have been sub)ected to separate effects testing. In one test, the cables were sub)ected to submergence conditions following exposure to a harsh acoident environment; however, radiation exposure was not included. In another test, the cables were qualified for harsh environmental conditions including radiation exposure, but were not sub)ected to a long term submergence test, The cables successfully passed the test criteria in both cases. Thus we have no reason to believe the BLPs to be unqualified for post-aocident use,'ut rather we laok dooumentation of sequential testing to assure full compliance with 10 CFR 50.49.

Additional indication of auxiliary feedwater flow is expected to be available through the FFIs as discussed above. Since this instrumentation and its power supply. are not sub)ected to the same DBA harsh environment as the BLPs, concurrent failure of this instrumentation with the ocourrence of the DBA is considered unlikely.

F