ML19345H000
| ML19345H000 | |
| Person / Time | |
|---|---|
| Site: | Crane  |
| Issue date: | 04/16/1981 |
| From: | Snyder B Office of Nuclear Reactor Regulation |
| To: | Hovey G METROPOLITAN EDISON CO. |
| References | |
| NUDOCS 8104230003 | |
| Download: ML19345H000 (4) | |
Text
{{#Wiki_filter:._ _. pf o UNITED STATES g , y )eq g NUCLEAR REGULATORY COMMISSION r, ' .E WASHINGTON, D. C. 20$55 t 8 %,*****/ APR 1 c D31 .S Docket No. 50-320 s S p-i ~ ( **s 20 yS 87 c-Mr, Gale K. Hovey . N gf Vice President and g, Director of TMI-2 Metropolitan Edison Company % j > \\' p P.O. Box 480 { Middletown, Pennsylvania 17057
SUBJECT:
MINI DECAY HEAT REMOVAL SYSTEM SURVEILLANCE REQUIREMENTS
REFERENCES:
1. Letter, from G. K. Hovey to J. T. Collins, TLL 645, December 9, 1980. 2. Letter, from G. K. Hovey to B. J. Snyder, LL2-81-0031, l February 13, 1981.
Dear Mr. Hovey:
i We have reviewed your letter of February 13,1981(reference 2),andhave approved your request for relief from the requirements of Section XI of the ASME Boiler and Pressure Vessel Code in accordance with the provisions of 10 CFR, Part )' 50.55 (a)(g)(6)(1) with the following exceptions. l' In addition to its design function as a decay heat removal system, other potential ~ uses for the Mini-Decay Heat Removal System identified to date include a backup means of Reactor Coolant System pressure control in the event of. failure of the Standby Pressure Control System, or the inability of the SPC system to n'aintain RCS pressure and inventory during a gross reactor coolant system leak or small break loss of coolant accident. Even though the MDHRS is one of several back-up modes available, it is identified as the preferred mode in your existing approved i procedures. An accident analysis for the MDHRS that was reviewed and approved by the NRC in our Amendment of Order, dated November 14, 1980, assumed MDHRS isolation by the system's main isolation valves (MDH-V1, MDH-V2, MDH-V18, MDH-V19), i and a complete draining of the Mini Decay Heat Removal System's volume onto the floor and into the drains of the auxiliary building. This analysis demonstrated that, provided the isolation valves perfonn their function as designed, the con-sequences of the postulated accident would be acceptable. This accident analysis ~ also discusses the possibility of electrical energization of all pressurizer-heaters j (1638 KW) resulting in a volumetric expansion of the reactor coola.nt and requiring l a compensating ielief capacity of 8.6 gpm. The MDHRS has an installed relief capa-l city of 53.5 gpm. The NRC staff reviewed your results of this potential overpres-1 810423 0 'co3 l 9
6 Mr. Gale K. Hovey surization event and performed an independent check, the results of which agreed with your conclusion. The balance of the valves in the MDHRS are either for maintenance convenience, flow control, or instrumentation isolation. While failure of any of these valves would necessitate the system being shutdown and isolated, they are not relied upon in the safety analysis. The four isolation valves shall be inservice tested in accordance with the re-quirements of Article IWV-3000 of Section XI of the ASME Code at least once within 31 days prior to the initial system startup and in accordance with the ASME Code thereafter. In addition, each valve in the main flowpath of the MDHRS shall be locked in its emergency use position and verified to be in that position at least once per 31 days. The only exception to this valve positioning requirement would be for testing the pumps, after which the valves shall ha returned to their emergency use position. The four pressure relief valves, MDH-V4A, MDH-V48, MDH-V8A, MDH-V8B, were tested prior to installation, the results of which have been reviewed by the staff and accepted. Relief from additional testing is granted for these valves because of their passive role during nomal system operation and ALARA considerations. It should be noted that we do not concur with your reasoning that additional valve testing promotes valve degradation. Our discussions with the diaphram valve vendor (ITT Grinnell) indicated that the valves in the MDHRS have sufficient conservatism built into their design to permit periodic cycling in accordance with the requirements of the ASME Code. Therefore, with croper operation, periodic cycling of these valves would not have been expected to degrade their reliability or increase their failure probability. Therefore, based on the above discussion, all Mini-Decay Heat Removal System valves are granted exemption from the inservice testing raquirements of the ASME Code with the exception of Main Isolation Valves MDH-V1, MDH-V2, MDH-V18 and MDH-V19. Also, according to the above discussions on the present modes in which the Mini-Decay Heat Removal System would be used and as stated in existing approved pro-cedures, we grant the requested relief from Article IWP-3000 of Section XI of the ASME Code and concur with your request to tast each of the two MDHRS pumps on a 3 month staggered basis with each pump being tested every 6 months. Per your justifications in reference 1, we agree with your proposal to measure inlet pres-sure, differential pressure, and lubrication level according to the criteria of Article IWP-3000 and to measure vibration amplitude using velocity via the Vibralarm as a method of also monitoring bearing performance. In suanary, the TMIPO concurs with the proposed testing schedule for the Mini-Decay Heat Removal System pumps as discussed in reference 1. Full relief from Article l IWV-3000 of the ASME Boiler and Pressure Vessel Code is granted for all valves in the MDHRS with the exception of the four main isolation valves MDH-V1, MDH-V2, MDH-V18 and MDH-V19. The four isolation valves shall be inservice tested in accor-dance with the ASME Code at least once within 31 days, prior to initial system startup, other than for pump testing, and shall be inservice tested per Article IWV-3000 after initial startup. c
Mr. Gale K. Hovey It is our position that the above described and approved inservice testing criteria for MDHRS pumps and valves and the positioning criteria shall be implemented (i.e., completion of the first periodic pump test and first verification of valve positions) within 7 days after receipt of this letter. Sincerely, 9 4.J A L Bernard J.~ Sn'yd , Prog Director TMI Program Off ce Office of Nuclear Reactor Regulation
4 e
o er Ge1y ntCowgnte sisaaeor, $tte Caerettaes. tui 2 force mie Islaae Alert. Inc.
wereesistee [41sen Comesar 23 Soute 21st $treet P. O. sea a60 Biecletoma. PA l'C17 iteret seorge e4 17104 als. Morfecte N. AamoM ar. f. D. Fallee
- 4. 8. y$
7NI I Liceastag $ugero9ger Casteset tle. PA 19320 eletreeelsten testen Company P. O. See 440 ses. Raren Shelden eteeleteun. 74 17057 ineleBA. herEDft, Retseen $ Weigg 172$ $ $treet. S.W.,1stte $06 ser. (. 6, nellece messington. DC 20006 Pwe Licensing gnager r.PU Servtce Corporetten Earl S. astfasa 100 latersece Part.ey Osweate Cav ty Consissioner e Persippeay, s) 07G5e Desante Cawty Cow tnevse e Freet one Mortet $treet ser. J. 9 Libermee. Esev re
- merrisew g. Pa 17101 e
e Serlect, Isr.els. Lineense 24 Bronensy Geeerammat Pwblice"1 ens lectten men fort. af 10004 State of Lterary es Pennsylvente sea 1601 Esucetten Sullatag er. G. F. Tremertege, (sevire Mamseert. PA 17127 5ase. Pittasa. Potts 41rs.ortege 1800 8 Street, e e Dr. Fa ord O. Swartz mesategton, DC 20036 Board of Sweer tsers v Londonderry *owasato De neitte a. Jerese nFD el Geyers Cnv ce Goes e set u 0.ter Det,e meeloteese. Pa 17057 Ces siege, Te 37330 Dr. Ltade v. Little
- v. $. te,5coamental Protectten Agency 5000 me-ontage Det e Begtes !!! Office ATTa : (!$ Coorstnoter salesga, ec 27612 Certis S=tistag ($1sta floor) sette e forter. [sewtre 6th one selegt $treets SCS t.ecutive isowse Petleselpete. PA 19106 P
- 0. Son 2357 Meretsawrg. P4 17120 Osspata Cownte Office teergency Preseregavs s acaerette mort Cenee Court sense, seen 7 5121 3 mis Casitol 6.ttstag Freat ead metet $treets herrissu g, P A 17120 Meretssw j. 74 1710) r r
Departseat of (avieraneaten sesou ces r (11ra metss. Eseve re $ Del eD#. HereDm 4etness a mets: ATTE : Otretter. Office of 172$ I $treet. t u. Sette 506 eastelegical meelta mesategten. DC 20006
- 7. O. Ses 2063
- erettu eg. PA 17105 pr. Ste.en C. taelly severner's Office of 5 tete 304 $. greet Street Pleaping one Develoemeat mecheattssw g, P4 1705$
ATTe - Cor einster, Fenasy1.eete r Cleertagaowse me. 'temas Geewsey P. O. Boa 1323 Sur ew of eastatica Protectica meerisesg. Pa 17120 P
- 0. los 2063 marrisovrg. PA 17120 ers. Enose O Core le02 Neeae Detwe Ibr. IIervie I. Lewis Maertsew g. PA 1710g r
650s treefore ?eerece Pat lese'pate. PA lstag se, etchere ponerts Tse Patriot es. Jeae Lee 412 meenet Street
- a. C. 3. See ?$21 harriseweg. Pe 1710$
Ettees. Pa 1731g er. sobert 8. Sorswet matter e Comen. Ceasemer Advocate gescoca 4 etices Desertseat of Justice nuclear Power Geaerettee 01,tsten $treecerry Seware.14te Fleer $ tte 420, 7735 01e f.sorgeteen Boed weretsev g PA 17127 Betheses, um 20C16 r ao6ert L. an ee. Esewire lese e SeitR. Esev re e w Atomic $e ety one Liceestag toerd r Asststeet 5eticiter U. 5. o clear Regulatory Casinessten an ee cae Aaerews w w P. O. Esa ' meshtagten. DC 20555 407 e. Front Street meertsevrg. *a 17108 Atoesc Sa'ety Sas Licensing toere Penel U. $. Ituclear Regulatory Casuptssten Jena E. esanica ChatrDersea oesatagtea. DC 20655 Coweate Co. Board of Ceau'1ssteners ceante Cavaty Courtnowse f ecat eae %reet 5treets Atomic Safety one Licenstag aseesi p eev story Caantgsio enei norre ss.rg, PA 1 71:1 U. 5. twcteer e i eesatagtsa. DC 2:555 Booert Q. Pellere C%esepene f eergy &1liance Doctettag one 5erette Settien 60g **oatset ter Stecet W. $. Ihsclear segwietery Cometsstep tel timore. "E 21218 estataerea. DC 20555 Chevrices seefore Jeetta a. Jonasrwe ,i i )., g,c,, g,, f a,tecamental Coeltttoa en euclear Power gg 433 enes 3*N p,,,gy g,gp g g gg g, t,,,,,g 9 gy I $ tate Cel'ege. Fa 16801 I W eersity Part. Pennsyl eent e 16eQ2 es. Friese terryatll Chatreersen Caelet o* for owclear power Plaat stegtate Soutaaet. (hetemag PSs tponemrat Cittrees 'or e Safe feve osunset 2610 (, eaeca "re've 264 moltoa $treet sile* aqua. :( 198C4 Lemoyne, Pa 17M3 netly $. seca satt-4. clear Grog segreseatteg fore 24% e ent leselente Street v rt, Pa 17ece o Jona Le Sa. Istutre Penasphemie Pweltc Utt11 ties Corestssten P. O tos 3265 .ercishirg. PA 17123
- oroep D. Ceavagaea. Essvtre f ee. Iere ens Cwdettagn#
2320 e. Secoad Street =arrissweg. 88 17110}}