IR 05000498/2006002
| ML061740478 | |
| Person / Time | |
|---|---|
| Site: | South Texas  |
| Issue date: | 06/22/2006 |
| From: | Clay Johnson NRC/RGN-IV/DRP/RPB-A |
| To: | Sheppard J South Texas |
| References | |
| IR-06-002 | |
| Download: ML061740478 (5) | |
Text
June 22, 2006 James J. Sheppa rd, President a nd Chief Nucl ear Officer STP Nuclear Ope rating Company P.O. Box 289 Wadsworth, TX 77483 SUB JEC T: ERRATA FOR SOUTH TEX AS PROJECT ELECTRIC GENERATI NG STATION -
NRC INTEGRATED INSPECTI ON REPORT 05000498/2006002 AND 05000499/2006 002 Dear Mr. S heppard: Pleas e repl ace th e Insp ectio n Scop e in S ectio n 4OA5 , "Impl ementat ion o f Temporar y Inst ruct ion (TI) 2 525/165 - Ope rati onal Rea din ess of Offsi te P owe r and Impa ct on Pla nt R isk"page 27 of the Rep ort Details in NRC Ins pection Rep ort 05000498/20 06002 and 05000499/2006002, dated May 18, 2006, with the enclosed revised change. This chang e is necessary to revise th e numbering of the Tempora ry Instruction and the Inspe ction Scope template that w as review ed during the i nspection pe riod.In acco rdance wit h 10 C FR 2.3 90 of th e NRC's "Rul es of Pr actice ," a co py of t his l etter a nd its enclosure will be made available electronically for public inspection in the NRC Public Document Room or fr om the Publicly Available Records (PARS) component of NRC's document syste m (ADAMS).
ADAMS is accessi ble from the NRC Web site at http://w ww.nrc.gov/readi ng-rm/ada ms.html (the P ubli c Ele ctroni c Read ing Ro om).Should y ou have a ny questions concerning thi s inspectio n update, w e will be please d to discuss them with y ou.Since rely , /RA/Claude E Johnson, Chi ef Project Branch A Divi sion of Reac tor Pro jects Docket Nos.: 50-498 50-499 Licen se Nos.: NPF-76 NPF-80 STP Nuclear Ope rating Company-2-Enclo sure: Page 27 of NRC In spection Rep ort 05000498/20 06002 and 0 5000499/20060 02 cc w/Encl osure: E. D. Halpin Vice Presi dent, Oversight STP Nuclear Ope rating Company P.O. Box 289 Wadsworth, TX 77483 S. M. Hea d, Manager, Li censing STP Nuclear Ope rating Company P.O. Box 289 , Mail Code: N501 4 Wadsworth, TX 77483 C. Kirksey/C.
M. Canady City of Austin Electric Uti lity De partment 721 Barton Sp rings Road Austin, TX 78704 J. J. Nesrsta/R. K. T emple City Publ ic Se rvic e Boar d P.O. Box 177 1 San Antonio , TX 78296 Jack A. Fusco/M ichael A.
Reed Texas Genco, LP 12301 Kur land Drive Houston, TX 77034 Jon C. Wood Cox Sm ith Mat thews 112 E. Pecan , Suite 1800 San Antonio , TX 78205 A. H. Gut terma n, E sq.Morgan, Lew is & Bockius 1111 Pennsylvania Avenue NW Washington, DC 20004 Instit ute of N uclea r Pow er Oper ation s (INP O)Records Cente r 700 Galleri a Parkway SE, Suite 1 00 Atlanta, GA 3 0339 STP Nuclear Ope rating Company-3-Director, Div ision of Compl iance & Insp ection Bureau of Radi ation Control Texas Department of State Health Services 1100 West 49th Street Austin, TX 78756 Brian Almon Public Uti lity Co mmission William B. Travis Bui lding P.O. Box 133 26 1701 North Co ngress Avenue Austin, TX 78701-3326 Environmental and Natural Resource s Policy Director P.O. Box 124 28 Austin, TX 78711-3189 Judge, M atagord a Coun ty Matagorda Co unty Courtho use 1700 Seve nth Street Bay City , TX 77414 Terry Parks, Chie f Inspector Texa s De part ment of Li cens ing and Regul ation Boiler Pro gram P.O. Box 121 57 Austin, TX 78711 Susa n M. Jab lon ski Office of Permitting, Remediati on and Registra tion Texas Commis sion on Env ironme ntal Qu ality MC-122, P.O. Box 13087 Austin, TX 78711-3087 Ted Enos 4200 South H ulen Suite 630 Fort Worth, TX 76109 STP Nuclear Ope rating Company-4-Electronic distribution by RIV:
Region al Ad minis trator (BSM1)DRP D irecto r (ATH)DRS Directo r (DDC)DRS D eputy Direc tor (RJC1)Senior Resi dent Inspector (FLB2)Branch Chief, DRP/A (CEJ1)Senior Project Engineer, DRP/A (TRF)Team Leader, DRP/T SS (RLN1)RITS Co ordin ator (KEG)DRS STA (DAP)S. O'Co nnor, OE DO RIV Coord inato r (SCO)ROPrep orts STP Site Secreta ry (LAR)SUNSI Rev iew Comp leted: __CE J_ADAM S: / Yes G No Initi als: _CEJ__
/ Publi cly Av ailable G Non-Publ icly Av ailable G Sensitive
/ Non-Sensit ive DOCUMEN T: R:\_REACTORS\_STP\20 06\STP2006-02 E RRATA.wpd
ML061740478 RIV:SP E:DRP/A RIV:C: DRP/A TRFarnh oltz CEJohnson/RA/ /RA/
6/22/06 6/22/0 6 OFFICIAL RECORD COPY T=Telephone E=E-mai l F=Fax Enclo sure-27-4OA5 Other.1 Temporary Instructio n 2515/165, Ope rational Re adiness of Offsite Pow er a. Inspection Sc ope The objective of TI 2515/165, "Operatio nal Readi ness of Offsite Power a nd Impact on Plant Risk," w as to confirm, through i nspections a nd intervi ews, the op erational readi ness o f offsite p ower syste ms in a ccorda nce w ith NR C requi rements. On March 6 -1 7, 2006, the i nspectors rev iewed l icensee proc edures and di scussed the attributes ide ntified in TI 25 15/165 wi th licensee personnel.
In accordance w ith the requirements of TI 2515/165 , the inspecto rs evalua ted the lice nsee's opera ting procedures used to assure the functionality
/operabili ty of the offsite pow er system, as wel l as, the ri sk asse ssment, emergen t wor k, and/o r grid r elia bili ty pro cedure s used to assess the op erabi lity and re adine ss of the offsite p ower syste m.The in formatio n gathe red w hile compl eting t his Tem porary Instru ction was forwar ded to the Office of Nuclear Re actor Regulatio n for further review and eval uation.*OPOP04-AE-0005, "Offsite Po wer Sys tem Degraded Vol tage," Revisi on 0.*Techni cal S pecifi catio n Limi ting Co nditi on for Op eratio n Acti on 3.8.1.1.e*OPOP01-ZO-0006, "Ex tended All owed Outage Time,"
Revisio n 13*OPOP01-ZG-002, "STP Co ordinator," Rev ision 1*OPOP04-AE-00 03, "Lo ss of Po wer t o one or more 13.8kV Stand by Bu s,"Revisio n 6*OPOP04-AE-0004, "L oss of Power to one or more 4 160 ESF Bu s," Revisi on 10*ERCOT Operating Guide Section 2.1 0, "System Vol tage Profile," M ay 1, 2005
- ERCOT Operating Guide Section 4, "Emergency Operatio n," September 1, 2 004*NRR Safety E valuatio n of Revise d Blackout Pos ition, dated July 24, 1995*OPGP03-ZO-0045, "Cen terPoint Energy Real Time Ope rations Emergency Operations Pl an," Revis ion 1*South Texas P roject Interconnecti on Agreement (Rel iant Energy, CP&L, San Antonio, and Austin /STP), d ated August 15, 2 002 b.Fin din gs No findings of signi ficance were identified.
Enclo sure-28-.2 (Closed) UR I 05000498;499
/2005006-02
- Inadequate M otor-Operated Val ve Operation Method Introduction
- The inspectors identified an NCV of 10 CFR Part 50, Appendix R, Secti on III.L.3, in that th e metho d used to pos ition motor-o perate d val ves ("hot-st icking")follow ing a fi re in the co ntrol room w as not inde pende nt of the fire ar ea. Sp ecific ally , a portion of each valve control circu it was l ocated in the control room.
A fire affecting those circui ts could resu lt in malop eration or ov erthrusting of the v alves.Description
- The licens ee utiliz ed a motor-operated valve repositioni ng method calle d"hot-sticking." Operators repositioned or checked the p osition of a giv en valv e by pushing in e ither the open or close co ntactor at the motor control center breaker for the valv e. Oper ators w ere tra ined that a contac tor w ill "suck i n" if th e val ve i s out o f its required positi on. Then the v alve w ill trav el to the reques ted position and the conta ctor will "pop out." For valves in the require d position, the contactor w ill immedi ately "pop out." The inspe ctors identified a concern w ith this method because the method utili zes circuits that a re not indep endent of the fire are a. If the control ro om circuit fail s or hot shorts, the method will not work as i ntended. The rel iance on ci rcuits that are within the fire area is no t consistent w ith 10 CFR Part 50, Appe ndix R,Section III.L.3, w hich states, in part, ". . . the alternati ve shutdow n capabil ity shal l be inde pendent of the spec ific fir e are a(s)." T he f ailur e mod es ar e des crib ed bel ow: 1.Open C ircuit: A control circuit failure (open circui t) could resul t in improper ind ica tion to o pera tors wh en h ot-s tick ing v alv es. In th is i nsta nce, foll owi ng a hot-sti cking at tempt, th e MOV contra ctor w ould immedi ately "pop o ut." Operators were trained that this response indicates that: "the valve is already in the required pos ition." In re ality, the valve should be in the opp osite positi on.2.Hot Short: A hot short could cause a valv e to start reposi tioning to an inappropria te position after operators had p erformed the hot-sticking meth od for the valv e. Since a n operator open s the breaker after repos itioning the valve, the valve would s till be a ble to reposi tion during the few seconds before the operator opened the b reaker. Some of the v alves ha d very s hort stroke times (abo ut 10 sec onds).3.Overthrust/To rque: In th e case whe re the necess ary c ontrol room ci rcuits are undamaged and a valve is in its required positi on, valv es and actuato rs can be overthrust and overtorqued w ell in e xcess of manufacturers ratings. The hot-sticking method dri ves the v alves i nto its seats with lo cked rotor torque. The licensee p erformed a detaile d analys is to eva luate the i mpact on the M OVs. The licensee c oncluded tha t, while catastrophic v alve/actuato r failure is n ot expected, the str ess to some v alve compon ents w ould exce ed the yie ld po int. As an ini tial correcti ve action , the licens ee trained the plant opera tors to ensure th at they understood the vulnerabi lities ass ociated w ith the hot-sti cking method. The li censee verified that adequate indi cation wa s avail able in a ll cases to ensure that mal operation of valves could be p romptly ide ntified and co rrected.
Enclo sure-29-Analysis: The failure to ensure that al l circuits relied on for safe shutdown i n response to a control ro om fire was free of the fire area wa s a performance defici ency. The i ssue was more tha n minor becau se it affected the rel iability objective of the Equipment Performance attribute under the Mitigating System s Cornerstone. Specifically, MOVs that ar e reli ed upo n to ac hiev e post fire safe shutd own were less relia ble b ecause parts of their control circuits coul d be damaged by the fire. A Se nior Reactor Analyst eval uated the sa fety si gnifica nce of th is is sue. Th e frequen cy of fi res tha t requi re evacuation of the control ro om and use of the remote shutdow n panels a t South Texas Proj ect a re 7E-6/y r. In the base cas e, i t is ass umed that the cond iti onal core dama ge probabili ty of a control room evacua tion is 0.1.
That is, approx imately 10 percent of control room ev acuations are assumed to resu lt in core damage. Therefore, to obtai n a delta-core-d amage-frequ ency incre ase of gre ater th an 1E-6/yr, the co nditi onal core damag e probab ility of a co ntrol ro om evacua tion, g iven the per form ance def iciency, woul d hav e to i ncreas e to at leas t 0.24. The Senior Re actor Analy st noted that, i n response to a control room fire, the licen see would a ttempt to recover all three tra ins of safe shutdow n equipment rather than just the one credited train. Further, mos t valve s were al ready in their required p ositions, w hich negated the need for repositioni ng. Finally , the licens ee had va lve posi tion indi cation at the remote shutdown panel for all af fected valves. Accordingly, the operator s could quickly troubl eshoot and ad dress a mispos itioned v alve. Therefore, th e Senior R eactor Analyst c oncluded tha t the increase d risk from the hot-stickin g method was i nsufficient to cau se more than a very small change in th e cond ition al co re dama ge prob abil ity. Also, the implications of large ear ly release would not be relevant to a risk increase in this i nstanc e. Con sider ing the abov e, the Senio r Reac tor Ana lyst eval uated the sa fety significance of thi s finding using M anual Chap ter 0609, "Signi ficance Determina tion Process," Appen dix F, an d determined th at the finding con stituted a lo w lev el of degradation for postfire safe shutdown equipment. As su ch, the finding w as of very l ow safety significanc e.Enforcement
- 10 CFR P art 50, Append ix R, Se ction III.L.3, states, in part, ". . . the altern ativ e shut down capab ilit y sha ll be inde pende nt of the speci fic fire area(s)." Contrary to th e above, a pproximatel y 25 M OVs utiliz ed for mitigation o f a fire in the control room, the licensee s pecified a v alve repo sitioning metho d that relie d upon circuits that w ere not inde pendent of the fire a rea. Because this issue is of very low safety significanc e and has b een entered i nto the correcti ve action program as CR 05-8004, this viol ation is be ing tre ated a s a no ncite d vi olati on, co nsiste nt wi th Secti on VI.A of the N RC En forcemen t Poli cy (N CV 05 00049 8;499/20060 02-04)..3 (Closed) UR I 05000498;499
/2005006-03
- Inad equate Fire P rotecti on Al ternate Shutdown Analysis Introduction
- The inspectors identified a noncited v iolation of 10 CFR Part 5 0, Appen dix R, Sec tion I II.L.1, becau se the thermo hydra ulic anal ysis was incon sisten t wi th actio ns al low ed in the So uth Tex as Pro ject li censi ng basi s for a c ontrol room e vacu ation. The inconsistencies aff ected the control room f ire timeline that operators mus t meet in order to successf ully accomplish safe shutdown. Specifically, the analysis Enclo sure-30-inappropria tely all owed four add itional man ual actions to be performed from the co ntrol room w hile the l icens e basi s all owed only one ma nual actio n to be performe d prio r to evacuating th e control room.
The other four manual actions are required to be performed in the fiel d.Description
- The inspectors performed a wal kdown wi th plant ope rators to veri fy that alternate shutd own actio ns could be performed withi n the time li mits derive d by the thermoh ydrau lic a naly sis. The inspectors i dentified that C alculation NC-7079, "Fi re Hazards Analysi s," Revisi on 1 (thermo hydra ulic anal ysis), cont ained inap propri ate as sumpti ons. F or alt ernate shutdo wn o utsid e the c ontrol room (c ontrol room fir e), Fi re Haz ards A naly sis R eport, Section 2.4.4, "Alternate Shu tdown," credi ts tripping the reactor from the control room and nothing more.
Licensee C alculation NC-7079 ass umed that the foll owing addi tional actio ns wo uld b e acco mplis hed pr ior to exi ting th e cont rol ro om:**Isolating main steam isolati on valv es**Isolating feedw ater**Secu ring cha rgin g **Isol atin g let down Since the l icensee had not obtaine d NRC appro val for the de viations to the lic ensing basis, credi ting performance of the add itional a ctions and u sing the timeli ne for completion o f the actions from the co ntrol room w as inappropri ate. Further, if the licensee c ompleted the a ctions outsi de the control room, there w ould be an impact on the the rmohydr aulic analys is result s and the a ssociat ed timeli ne. Specif ically, performing these actio ns inside the control roo m ensured that the reactor coola nt system process variable s remained w ithin those values p redicted for a l oss of normal ac power, as re quired by 10 CFR Part 50 , Appendix R,Section III.L.1. For a lo ss of normal ac power a t South Texas Project, the predi cted pressuriz er level (a reactor cool ant syste m proce ss va riabl e) rema ins w ell w ithin the i ndica ting ra nge. The NRC Enforcement Manual, Section 8.1.7, states, in part:
"Failure to have an adequate wri tten evalu ation ava ilable for an area in w hich Appen dix R co mpliance i s not apparent will be taken as an indication that the area does not comply with NRC require ments . . . ."Analysis. The failure to have an a dequate writte n evalua tion avai lable for a co ntrol room fire scenario was a perform ance deficiency. This issue was more than minor because it affected the Miti gating Systems Co rnerstone attribu tes of protection from ex ternal factors (fire). The inade quate analys is overesti mated the amount o f time avail able wh en acc omp li shi ng s hut dow n a cti ons an d, d uri ng w al kdo wn s, t he in spe cto rs c oul d n ot v eri fy compliance with the requirements. An NRC Senior Reactor Analyst evaluated this issue. The frequency of fires that require ev acuation of the control room and use of the remote shutdown panels at South Texas Proj ect is 7E-6/yr. In the base case, it is assumed that the conditional core dam age probability of a control room evacuation is 0.1. Th at is, appro ximat ely 10 per cent o f control room e vacu ation s are a ssumed to result in co re damage. Therefore, to ob tain a del ta-core-damage-frequency i ncrease of Enclo sure-31-greater than 1E-6/y r., the conditi onal core da mage probabili ty of a control room evacuation , given the p erformance deficiency , would have to i ncrease to at l east approx imatel y 0.2 4. The S eni or R eact or A nal yst note d tha t the add iti onal acti ons that ope rato rs w oul d tak e prior to evacuation of the contro l room would cause a delay of approximately 90 seconds b eyond the times assumed i n the analy zed recov ery action timeline. The Senio r Reac tor Ana lyst determ ined that a delay of this magnitu de w as in sufficie nt to cause more than a very s mall change i n the conditi onal core da mage probabili ty. Also, the implications of large ear ly release would not be relevant to a risk increase in this insta nce. B ased o n the a bove , the S enior React or Ana lyst eval uated the sa fety significance of thi s finding using M anual Chap ter 0609, "Signi ficance Determina tion Process," Appen dix F, an d determined th at the finding con stituted a lo w lev el of degrada tion fo r postfi re safe s hutdow n anal ysis. Acco rdingl y, the findi ng was of ver y low safety significance.
Enforcement
- 10 CFR P art 50, Append ix R, Se ction III.L.1, require s that reactor coo lant system process variable s be maintai ned with in those pred icted for a loss of normal ac power. License Condition 2.E specifies, "STPNO C shall implement and maintain in effect al l prov isio ns of the appro ved fi re prot ectio n progra m as de scribe d in t he . . . Fire Haza rds An alys is Re port." The Fi re Haz ards A naly sis R eport, Secti on 2.4.4, "Al ternate Shutdown,"
credits trippi ng the reactor from the co ntrol room and nothing more. The licensee u sed Calcul ation NC-707 9 to demonstrate c ompliance w ith 10 CFR Part 50, Appendix R, Section III.L.1. Contrar y to the above, Calculation NC-7079 inappropriately credited sev eral additi onal action s from the control roo m, includin g main steam isol ation valve closure, feedw ater isolati on, securing cha rging, and isola ting letdow n. Because this issu e is of ver y low safet y signif icance an d has been entered into the c orrect ive actio n progra m as CR 05-85 07, thi s vi olati on is bein g treate d as a n NCV , consi stent w ith Secti on VI.A of the N RC En forcemen t Poli cy (N CV 05 00049 8;499/20060 02-05).4OA6 Meetings, Including Exit The results of the A LARA insp ection we re presented to Mr. Gary P arkey, Vice P resident of Generation, and Mr. Thomas Jorda n, Vice Pres ident of Enginee ring, and other members of the staff, on February 9, 2006.On February 2 7, 2006, the i nspector conduc ted a teleph onic exi t meeting to presen t the emergency prepare dness inspe ction results to Mr. A. M organ, Supervi sor, Emergency Plann ing, w ho ackn owl edged t he find ings. On April 10 , 2006, the i nspector conduc ted a teleph onic exi t meeting to presen t the electrical URI inspecti on results to Mr. K. Taple tt, Licensing S taff Engineer, who acknowledged the findings.
The results of the re sident insp ection we re presented to Mr. Gary P arkey, Vice President of Genera tion, and othe r members of licens ee management on A pril 13, 2006.
Enclo sure-32-During each ex it meeting, the i nspectors asked the licensee representativ es whether any materials examined during the inspection should be considered pr oprietary. No proprietary information wa s identified.
4OA7 License e-Identified Vi olations The followi ng violati on of very low safety significance (Gree n) was i dentified by the licensee a nd is a v iolation of NRC requirements which mee t the criteria of Section VI of the NRC Enforcemen t Policy , NUREG-1600, for b eing disposi tioned as N CVs.Technical Sp ecification 3.5
.2 requires, in part, that, wi th only tw o of three required essent ial cooling water loops operable , three loops be re stored to opera ble within 7 days or be i n at l east h ot stan dby w ithin 6 hou rs. Co ntrary to thi s, Uni t 2 con tinue d to op erate at 100 perce nt pow er wh ile E CCS Tra in 2C was inope rable for an i ndeter minate time greater than 7 day s due to missi ng T-drains in M OV Motor 2-S I-0019C. The l icensee entered the performance deficiency into their corrective a ction program as C R 05-13606 for resolution.
This finding is of very lo w safety si gnificance becaus e of the avai lability of two other trai ns.ATTACHM ENT: S UPPLE MEN TAL INF ORMA TION