ML20034A357
| ML20034A357 | |
| Person / Time | |
|---|---|
| Site: | South Texas  |
| Issue date: | 04/13/1990 |
| From: | Office of Nuclear Reactor Regulation |
| To: | |
| Shared Package | |
| ML20034A353 | List: |
| References | |
| NUDOCS 9004230117 | |
| Download: ML20034A357 (4) | |
Text
..
. n.,[*,,
UNITO STATES
+
' r!-
NUCLEAR REGULATORY COMMISSION 3e t.
wasHiwofow. o. c. nosss i
\\,..... h l
l l
SAFETYEVALUATIONEY,THEOFFICEOFNUCLEARREACTORREGULATJ_0!N 0
RELATED TO AMENDMENT NOS. 14 AND 4 TO FACILITY OPERATING LICENSE NOS. HPF-76 AND NPF-80 i
i HOUSTON LIGHTING & POWER COMPANY i
l
~ CITY PUBLIC SERVICE BOARD OF SAN ANTONIO.
f CENTRAL POWER AND LIGHT COMPANY CITYOFAUSTIN.TER.S P
DOCKET NOS. 50-498 AND 50-499 l
SOUTH TEXAS FROJECT, UNITS 1 AND 2 t
1.0 INTRODUCTION
3 Dy aprlication dated March 7, 1990, Houston Lighting & Power Company, (t.al.Ix(AtoFacilityOperatingLicenseNosthe licensee) requtated changes to t i
(Append
.HPF-76andNPA80)forthe South Texas Project, th;its 1 and 2 (STP-1 and STP-2). 'The proposed changes would revise Table 3.3-10 of Technical Specification (15) 3.3.3.6 to eliniinate the stetdown requirenient of ACT10N 38 for loss of one of four l
channels of pressurizer icvel instruinentation. The change would add a rtw action statement (ACTION 43) that would pertnit 31 days of operation.
with only two channels operable, 7 days of operation with only one channel operable, and 48 hours5.555556e-4 days <br />0.0133 hours <br />7.936508e-5 weeks <br />1.8264e-5 months <br /> with no channels opereble.
?.0 DISCUS $10N The licensee's TS currently require the plant to be shutdown if one i
pressurizer icvel instruir.entation channel is inoperable and cannot be restored within 90 days. The current TS alsc require the pitot to be shutdown if two channels are inoperable and cannot be restored within 31 days, three channels are incterable and cannot be restered within 7 days, and four channels are inoperable and cannot be restored within 48 hours5.555556e-4 days <br />0.0133 hours <br />7.936508e-5 weeks <br />1.8264e-5 months <br />.
The proposed TS change would revise Table 3.3-10 to eliminate the shutdown i
requirenent for the loss of one channel of pressurizer level instrumentation.
the TSs would still require the plant to be shutdown in 31 days with two channt.ls inoperable, 7 days with three channels inoperable, and 48 hours5.555556e-4 days <br />0.0133 hours <br />7.936508e-5 weeks <br />1.8264e-5 months <br /> t
with four channels inoperable.
These requirements would be incorporated in a-new action statto.trt.
9004230117 900413
$8 DR ADOCK 0
,sr q.,
i
,7,
.i' Pressurizer level is a Category 1 pareracter for post tecident inonitorins instrutr>entaticn as defined in accordance with Regulatory Guide (k6) 1.9T.
}
The RG recomrnends two redundant channels of instrumentation. STP-1 and STP-2 each have four redundant channels of-instrunientation for this parameter.
1 Turther, a comparison cf the-licensee's proposed TS' change with the-existingWestinghouseStsndardTechnicalSpecifications(WSTS)andthe 3
proposed Improved Westinghouse Standard Technical Specifications (IWST).
irdicates t1at the STP-1 and STP-2 have a higher degree of redundancy than that included in the bases for either the WSTS or-the IWSTS.
The WSTS require the use of two channels of pressurizer.ltvel instrumenta-tion and the IWSTS require the use of three channels of 'instreentation.
~'
By providing a fourth channel of instrunntation the licensee 'nas proviced an additior.81 level of redundancy beyond that cf the IWSTS and two levels of, redundancy beyond the WSTS.
l The prorosed change, whilt sirilar to that proposed in the;IWSU, still has an additieral 1 ciel of redundancy ar.d therefcre an additional-mtrgin of safety. The proposed change will nct ir. pact the safe cperation of the plant. Therefore the proposed TS change is acct.ptable.
3.0 CIRCUMSTANCES l
In its letter of Itarch 7, 1990, the licensee infortsed the staff that it-was c p reting under the conditions of TS 3.3.3.6, ACT1014 38 and that, h uhout tN proposed license amendrent, the plant would ur.dergo an unscheduled shutdown initiation on April 16 1990. Consequently,the i
staff prepared a fictice of Consideration of:Issuarce of Amendment to' Fecility Operating license and Proposed Nu Significant Hazards i
Consideration Determination and Opportunity for Hearing which was~
published in 'the Federal Register as an individca1' notice on March 16, 1990 (55 iR 10017). The 30-cay comment period expires at 11:59 p.m. on April 16, 1990.
By letter dated April 3 1990, the licensee informed the staff that the South Texas Project, Unit 2 was operating under TS 3.3.3.6, ACTION 3Ba which requirts plant shutdown to begin at 2:51 a.m. on' April 16,1990, if:
the. prcrcstd ar..endtr.ent was'not implemented before that time.
(
The licensee stated that operation with one of the four channels inoperabic ccostitutts sde operaticn because of the redundancy.
In addition, an unnecessary shutdown would involve plant system transients with associated cyc1ts E.nd stresses on equipment as well as an increased potential for safety systera challenges. The staff concurs with those conclusions.
L t.
I 4
.;,e..
..[
y 9
1
,. The staff in its notice of March 16, 1990, stated that the Comission t.ay-issue license amendments before the expiration of the 30-day notice.
period, if-f ailure to do so would result-in derating or shutdown of the facility, providing that the Comission's final-determination is that the arendments involve no significant hazards consideration.
Further, the final determination will considct all public and state coments received and the Comission will publish a notice of, issuance. The Comission has concluded that apprcul of the proposed changes _will not adversely affect the public health and safety.
Consequently, issuing the license amendn.ents prior to expiration of the 30-day coment period will not endanger the public health and safety. On the contrary, requiring plant shutdown,,
with the ensuing restart after the end of the 30-day coment period would sutject the plant to unnecessary transients that are less desirable _to-the public health and safety than contiruo steady state ~ operation.
Accordingly, the Comission has determined that there are circumstances.
warrenting expeditious action by the Comission.
1 4.0 FINALHO'SICHIFICANTHAZARCSCONSTERATIONDETERMINATION The Comission's regulations in 10'CFR 50.92 state that the Comission may nah. a final c'etermination that a license. amendment involves no significant hazards consideration, if operation of-the facility, in accordance with the an.endment would not:- (1)Involveasignificant increase in the probability or consequences of'any accident previously evaluated; or (?) Create the pcssibility of a new or difft-rent leind of.
accident frem any accident previously evaluated;- or' (3) Involve a signi-
' i ficant reduction in a nargin _or safety._
q The propcsed change does not involve a significant increase in the probability or consequences of an accident previously evaluated.
1 Elinitatien the shutdown requirement in the AC110H statement for loss ofc one of four channels of post-accident monitoring instrumentation dces not 1
affect the prcbebility cf an accident because monitoring instrumentation j
cce.s not contribute to accident probability. The accident mitigation-function of the-subject instrumentaticn is addressed by other TS (e.g.,
~
TS 3.3.1), which are unaffected by this proposed change. Additionally,:
1 three channels of Fressurizer Level can monitor the pressurizer level in a post accident rode and provides one more channel than the redundancy specified in RG 1.97. Therefore, the consequences of an accident are-nct affected by the proposed change.
i The proposed change does not create the possibility cf a new or different kind of accident frcm that previously evaluated. The proposed change 1
involves no changes to the station or its design bases nor does'it impose 1
any new accident scenarios.
i The proposed change does not create the possibility cf a new or different-kind of accident from that previously evaluated. The proposed change does not invc1ve a significant reduction in a margin of safety. The channels dc not contribute to the accident mitigation function.
I
l
,.3 j
i 4
5.0 STATE CO.N.S.ULTATION in accordance with the Como.ission's regulations, efforts were made to contact the Texas State representative. The state representative was.
centacted and had no comments, i
6.0 ENy_lRONMENT,ALCONSIDERATION l
The amendn'ents invcive a chtr.st in a requirement with respect to-the installation or use offa facility component located within the restricted-i area as defined'in 10 CFR Part 20 and changes ~in surveillerce requirements.
l.
Ttt staff has determined that the aniendn.ents involve no significant L
increase in the amounts, and oc significant change in. the. types, of any.
I effluents that may be released offsite, and that there is no significant increase in individual or cumulativt cccupationel radiation exposures.
The staff has also detern.ined that the anendments do not involve a significant hazards considertticr.. Accordingly,' the cmendr..ents r.eet the eligibility. criteria for categorical exclusion set.forth in 10 CFR'Section-51.22(c)(9).- Pursuantto10CFR-51.22(b),no~ environmental 1r.4tct; state-4 rent er environmental assessnint neec be prepared in-connection withi the issuance cf the ouindtdntt..
7.0 CONCLUSION
Dastd upon its evaluation of the proposed changes to the South Texas _
3 Project, Units 1 and 2 Technical Specifications, the staff _ hts concluded that:
(1) there is reasonabic assurance that the health and safety: of the ublic will nct te endangered by operation-in the propcsed raanner, and-I p(2) such activities will be conducted in compliance with the Commissiun's-regulations and the issuance of the arendn.tnts'uill not be inimical to the coramon defense end security or to the health ard' safety:of the public..
The staff, therefore, concludcs that the proposed changes are~ acceptable.
Date: April 13, ISSO i
Principal Contributors:
D. Marcus G. Dick
?
?
i
.-