ML20106A885
| ML20106A885 | |
| Person / Time | |
|---|---|
| Site: | Grand Gulf  |
| Issue date: | 09/25/1992 |
| From: | Cottle W ENTERGY OPERATIONS, INC. |
| To: | NRC OFFICE OF INFORMATION RESOURCES MANAGEMENT (IRM) |
| References | |
| GL-92-04, GL-92-4, GNRO-92-00126, GNRO-92-126, NUDOCS 9209300099 | |
| Download: ML20106A885 (6) | |
Text
-
Entergy Operabons ine.
-::=~ ENTERGY
.p.
W, T. Cotue September 25, 1992 U.K. Nucionr Regulat ory CommlNnion fin i l St a t inn Pl-1'4 7 Washingt on. D.C.
70 % 5 At t ent lon:
Doc unie n t Conttol Desk Subjert-Grnrel Gulf Nuclent Station Unit 1 thnket. No. 50-416
- 1. i c e n s e No. NPI'-29 Kespone to Generit het t er 92-04; Renoint ion of t he insnes kelnt rol t o Ronct or Vessel Wat et 1.evel JnstrumentntJon in itWRs Pu r r.nn u t to 10C FK 50. 5 4 ( l')
GNRO-9?/n012(.
Cent lemen:
On August 27 1992, T.ntergy Operntions, Inc. (1:01) received Gonctic 1.e t t e r 9?-04, Resolut inn of t he lasnes Relat ed to konctor Vessel Wat er I.evel inst rument at lon in ItWRs Putsunut to 10CFR50.54(F).
The let t er iequires licensnon t o submit it.formntion regarding the pot ent ial for Ronctor Vensel level indicat ion en ors due to the ef fect s of noncorniensible gnnses in a r aphi depressurinnt ion event t.ud t o cotif i rm thnt the safety funct ionn of thnir vessel level inst rumentat ion are being mot. The 1:01 tesponse for G ra nti Gulf Nuclent Statton (GGNS) is attached.
The at tached responso descr ibes t he impact of pot ent ial level itvlicat ion errors on aut omat ic safet y syst em runt operat or responses.
Opera t or responne inclinles short and long term act ions atul opernt or act ions p1 esc rlbod in emergency opernt ing procedures during and a f ( or n11 1iconsing bnn is 3.cc ident s nini transients.
Short term actinos t aken to of fset thn imr,ct. of pot ent tal level linlient ion errorn at o also described in t he at t ched, l.ong t erm correct (vo net tons by GGNS, which may include hardware nt sli f icat ions, wilI be in conjnnet ton with the findings atul conclusions of
- t. h e itWR Owners Gronp.
28:070
'll G9209241/SNI,1CFi.E - 1 fl 8
9209300099 920925 PDR ADOCK 05000416 p
PD51 r.
__ - -___ - --__-__ - - - _ - _-_______- -____-____--_ -__ ___ - _-_-__ a
o Sep t ernbe r 25. 1992 GNRO-42/00126 Page 2 of 3 Th i r. informat ton is being providml under of firmation pursuant to 10CFR50.54(f).
Please ndvino if you require any additional information on t his mat t er.
Yours truly, c o f~~~ Cocx c WTC/CI)ll/nms n t t n clinien t : Response to NkC Onneric I,et t er 92-04; Resolut ion of thn Issues Relat ed to Rnactor Vessel Level Inst rument at ion ec:
M r. 1). C. llint z (w/n)
M r. R. 11. 11ernhard (w/a)
Mr. R, B. McGehen (w/n) fir. N. S. Reynolds (w/n)
Mr, 11. L. Thoman (w/o)
Mr. Stewart 1). Ebonter (w/n)
Reglonal Administrator U.S. 3 4clent Regulatory Commission Reg i or.
'l 101 Hortet.tn St., N.W., Suito 2900 Attanto, Georgin 30323 Mr. P. W. O'Connor, Project Manager (w/2)
Of fice of Natinar React or Regulat ion li.S. Nuclear Regulatory Commission Hall Stop 13113 Washington, D.C.
20555 G9209241/SNh1CFLR - 2
_m_.____.m.
_ _ _ _ _ ~ _ _ _. _ _ _
_ _ _.. _.. _ _....... ~ _ _ _. _ _.. _ _ _ _ _ _ _ _.
I 11EFORE Tile UNITED STATES NUCLEAR REGUl.ATORY COMMISSION l
I LICENSE NO. NPF-29 1
1 DOCKET NO. 50-416 IN Tile HATTER OF MISSISSIPPI POJER f LIGilT C0!!!'ANY
)
and SYSTEH ENERGY RESOURCES, INC.
and i
SOUTil MISSISSIPPI El.ECTRIC POWER ASSOCI ATION and ENTERGY OPERATIONS, INC.
AEEIRMAIMN
)
I, W. T. Cottle, being duly swo,n, st.nto that I am Vice President, Operat ions GGNS of Entergy Operations, Inc.1 that on behalf of Ent ergy Operations, Inc., System Energy Resources, Inc., and South Mississippi Electric Power Association i am authorized by Entergy Operations, Inc. to sign and file whh the Nuclent Regulatory Commission, this response to Generic Lntter 92-04 for the Grand Gulf Nuclear Stat Jon; that I signed this responsn as Vice President, 0porat.Jons CGNS of Entergy Opnrations, Inc. ;' and thnt the stat em^nt s s'inde and the matters set forth therein -arn true and correct to the best of my knowledge, ittformat ion and belief.
t c rC~~Cm==::::-
i W. T. Cottln-i l
STATE OF HISSISSIPP1 COUNTY OF CLAll10RNE SUBSCRIDLD AND SWORN TO bnfore me, 7 otary Pub N
u, in and for the County and State above named, this Jf/
day of
_ 'rg/n..lo-
, 1992.
_(SEAL)
Ajk
,e ad
[
Notary PubMc Hy commission expires:
andu 9&J9W G9209241/SNLICFLR - 4
Attachment. to GNRO-92/00126 0
pnge 1 of 3 e
t' RESPONSE TO NRC GENERIG LETTER 92-04 Resolution of thn issues !! elated to Roactor Vessel Level Instrumentation Tho following information represents the Grand Gulf Nucinar flation iesponsn to the si cific Re!]uested Actfons in t he Generic Let ter for Grand Gulf Nuclonr.itntlon.
Requested Acti_on_1 1.
In light of potentini errors result ing fiom t he ef f ect s of non-condensables gas, ench licensco should determine:
n.
The impnct of potentini level indicatlon ortors on automatic safety system responso during n11 licenning basis t rannients and accidents; b.
Thn impact of pot ent1 t t w.
ica"'on errors on operator's short and long tnrm a t h:i" h; av
' Iter all licensing basis nccidents and transion c.
The impact of pot ent ini level indient ions errors on operator actions preser(bosi in emergen :y operating procedures or other af fected procedures not cover <d in (n).
Responso 1.n., The llWR Owners' Group (BWROG) provided to the NRG nnd nach of thn member utilities a report on BWR Reactor Vnssel Water Level instrumentation, Revision 1, August 28.-1992.
This report.
addresses the safety impact of potentini wate: level indication errors on automatic system responso during al_1 licensing basis t ransients and accidents.
This nnalysis basis is contained in i
Sect ion 6.0 Safety Analysis of thn report and is summarized in Section 2.2 Plant Responses _tt p29tulated Accidnnt Scenarios.
'The informntion in the ItWROG report is applienble to the design of Grand Gulf Nuclear Station; this conclusion in based'on our documented review of the report and the evnluation mndo by 3
Gennrnl Electric as contained in Attachment 2 to the repcrt.
Grand Gulf Nucient Station reengnizes that. thorn are _ di f ferences between the designs of ItWR planto and systems; however, our review of the report (including Attachment 2 conclusions) reinforens Grand Gulf Nuclear Station general underst anding.that t he bas ic plant. response to thn design basis transient s and accident events is sufficiently similnr to obvinto the need for additional plant unique detnited re-annlysis.
An'nvaluntion of the applicability of the 11WR00 report to the GGNS design was performed.
1.b. The 14ROG report addresses, in section 6.9 Operator Responses.
t he opernt.or actions t hat. could be ant icipat ed in response t o potential water level indication errors, in t he short term the 09209241/SNLIGl'i.R - 5
i e
At t achment to GNRO-92/00126 Page 2 of 3 p
repott discusses in section 6.0 that the out omat ic safety actions will be performed as necessary.
Additional guidanco has been provided to the plant operations personnel as a result of the itWROG Emergency Procedures Committen (EPC) recommendntion letter of August 19, 1992.
Onco avnilable, this sensitlxing guidanco was provided to the operators na part of their shif t turnover activities ns they como back on duty.
This was nccomplished by enclosing copies of the let ter in the Operations night orders.
The int erim guidnoce information hns sensit f xed thn operntors to the possible concerns wit h necurnt o watnr levnl tendings following n rapid depressurization whfic not necessit at ing a chntige to the existing long intm guldunco i
provided.in t hn Emergency OpetatIng Procedures (EOP).
.l.._c.
As atated in section 6.9 of (he report and the 1.b. responNO above the operators have miequato information in the present EOPs as augment ed by t he recent information communication from the EPC.
This is tc{nforced by the itWROC letter of September 24, 1992, in response to NRC concerns in n letter dat ed September 9, 1992. The EPC is continning to review the i
potentini need for nny ndditional guidance in the Emergency Procedure Guidelines (EPG) to further address the pot ential water levnl indication errors.
Such review will t ake into account the Information from the itWROG program of an11ysis and t esting regard f rig t his issun.
Roquested Act,lon 2 2.
linsed upon the results of (1), above, each licensco should notify the NRC of short term actions tnken, such as:
n.
Porlodic monitoring of levol lustrument nt ion system lenkngo; nud.
b.
lmplementnt ion of procedures and operat or training to nanuro that potentint level nriors will not. result in impropor operator nctions.
R,nsponse f
1 2.
Grand Gulf Nucinnt Station has informed it s oporntors of tho j
information contained in the intter from the EPC. The existing informat.lon about the ccnfigurntion of the cold leg water level instrumentation hns been reviewed and additional verification of insulation integrity will take placo at the next refueling outngn.
Tho-available information has been providod to the __
11WROG to be factored into the test configurations in thn ilWR00-program (provided to the NRC in the August 12, 1992 letter from the ilWROG).
Thn significanco of different characteristics _ of the configuration of cold leg water Invol Instrumentat ion will bo bet t er undorst ood a f t er the itWR00 program t est information is availabin.
G9209241/SNhlCFLR - 6 4c-+--my4
-m m-e-w,--m----,-e+,*
w w-.m--
,-e-_.ir
,,m-,--,,n p,' v w -
r'7
-yr-r--+-r,-~~-:---eetar+yp+--rgr,
_..___. _._ _.. _ _ _.. _ _ _._m._._ _ _. _ _ _. -. _ _.. _ _ _
I Atiaclomut to GNRO-92/00126 I
o Page 3 of 3 Short term actions taken on planned include:
Tracking reactor water level following scrnms or during l
shutdowns to identify unusuni responses, i
Gont inning to perform chnunel checks on the reactor water icvel instrumentation.
Inf or mat lon was provided to Plant Operators, 16G Technicinns, and 16G Plannets describing how any identified lonks on reactor water level instrumentation nre significant and need to be documented and correcteel in n timely manner.
A lesson plan was developed concerning this phenomenon, and hun been incorporated into initini 1.f cense Operat or Training, and in currently scheduled to be incorpornt.ed into I.icensed Operator Requalificat ion Training in Inte 1992.
4 The response to 1.b. discusses procedures and operator training to assut e thnt pot ential level errors will not result in improper operator net ions.
Rtiquested.Ac_t1on 3 i
3.
Each licensco should provide it s plans and schedule for corrective nctions, including any proposed hardware modificat ions necessary to ensure the levnt instrumentat. ion system design is of high functional reliability for long term operation.
Since this instrumentation plays an import.nnt role in plant safety and is required for both normal nnd accident. condit f ons, the staff recommends that each utility implement its longer term actions to assure n invel lustrumentation system of high functional reliability at the first opportunity but. prior to starting up af ter the next refueling outage commencing 3 months af ter the date of this letter.
Resp _onse 3..
Grand Gulf Nuclear Stat lon endorses the 11WROG plans originally provided in BWROG letter to the NRC on August 12. 1992 (Reference n).
Grand Gulf Nuclear Stat.fon alno renf firms support of the BWRp9 pinn by _endorsin,s _the BWROG letter of September.24, 1992 (Reference b).
Grand Gulf Nuclear Station facilities are scheduled to start their next refueling outage for Grand Gulf Nuclear Station in the fall of 1993.
If the BWROG Program indicates that modificat Ions are necessary to
- assure that the level instrumentnLion is of high functionni reliability, such modification schedule will be provided to the NRG nt. that time.
l G9?09241/SNblCl?LR - 7 7,
d