Provides Suppl Rept to ACRS Re Facility SE on 691124, Discussing Matters Including Site Flooding,Inservice Insp, Seismic Design Adequacy,Instrumentation & Control Items & Turbine Bldg Secondary Closed Cooling Water SysML20125A429 |
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Millstone |
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12/24/1969 |
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US ATOMIC ENERGY COMMISSION (AEC) |
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ML20125A422 |
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FOIA-92-198 NUDOCS 9212080342 |
Download: ML20125A429 (9) |
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Category:SAFETY EVALUATION REPORT--LICENSING & RELATED ISSUES
MONTHYEARML20211G9631999-08-30030 August 1999 SER Accepting Licensee Response to GL 96-05, Periodic Verification of Design-Basis Capability of Safety-Related Motor-Operated Valves ML20196J2191999-06-30030 June 1999 SER Concluding That Licensee USI A-46 Implementation Program,In General,Met Purpose & Intent of Criteria in GIP-2 & Staff Sser 2 for Resolution of USI A-46 ML20207G6411999-06-0303 June 1999 Safety Evaluation Supporting Amends 105,235 & 171 to Licenses DPR-21,DPR-65 & NPF-49,respectively ML20206M4631999-05-11011 May 1999 Safety Evaluation Supporting Alternative Proposed by Licensee to Perform Ultrasonic Exam on Inner Surface of Nozzle to safe-end Weld ML20206G6221999-05-0404 May 1999 SER Accepting Util Request to Apply leak-before-break Status to Pressurizer Surge Line Piping for Millstone Nuclear Power Station,Unit 2 ML20204H7131999-03-17017 March 1999 Safety Evaluation Concluding That NNECO Provided Adequate Justification for Deviations from RG 1.97,Rev 2, Recommendations,For Instrumentation Monitoring CST Level & Containment Area Radiation at Mnps Unit 2 ML20204C9441999-03-10010 March 1999 Safety Evaluation Denying Licensee Request for License Amend to Revise Frequency of Certain SRs for Electrical Power Sys ML20207L2631999-03-0505 March 1999 Safety Evaluation Supporting Amend 104 to License DPR-21 ML20207L5961999-02-22022 February 1999 Safety Evaluation Concluding That Code Requirements,Which Require 100 Percent Volumetric Exam of RPV flange-to-shell, Impractical to Perform to Extent Required & That Alternative Provide Reasonable Assurance of Structural Integrity ML20203D7601999-02-11011 February 1999 Safety Evaluation Supporting Millstone 1 Certified Fuel Handler Training & Retraining Program ML20196B0501998-11-24024 November 1998 Safety Evaluation Re Licensee 960213 Submittal of 180-day Response to GL 95-07, Pressure Locking & Thermal Binding of Safety-Related Power-Operated Gate Valves, for Plant,Unit 2 ML20155K1981998-11-0909 November 1998 Safety Evaluation Re Application of leak-before-break Status to Portions of Safety Injection & Shutdown Cooling Sys ML20195B8711998-11-0909 November 1998 Safety Evaluation Approving Revised Evaluation of Primary Cold Leg Piping leak-before-break Analysis for Plant ML20155C3781998-10-30030 October 1998 SER Denying Amend to Allow Changes to Fsar.Nrc Found That NNECO Had Not Considered Diversity Provided by Switch in Control Room That Removes Power to 1 of 2 MOV in SDC Sys Flow Path in Evaluation of High Low Pressure Design ML20155C8441998-10-29029 October 1998 Safety Evaluation Accepting Licensee Proposal to Withdraw ATWS Test Commitment ML20238F2781998-08-27027 August 1998 SER Related to Proposed Rev 20 to Northeast Utilities Quality Assurance Program Topical Rept for Millstone Nuclear Power Station,Units 1,2 & 3 ML20237D5001998-08-20020 August 1998 SER Approving Code Case N-389-1, Alternative Rules for Repairs,Replacements,Or Mods,Section Xi,Div 1 ML20236U7051998-07-22022 July 1998 Safety Evaluation Granting All Requests for Relief W/Exception of Requests RR-89-17 (Authorized for Class 1 Sys Only) & RR-89-21.Requests RR-13 & RR-14 Will Be Addressed in Separate Evaluation ML20236K6971998-07-0101 July 1998 SER Accepting Third 10-year Interval Inservice Insp Program Plan,Rev 2 & Associated Request for Relief & Proposed Alternatives for Plant,Unit 2 ML20236K3531998-07-0101 July 1998 Safety Evaluation Supporting Amend 218 to License DPR-65 ML20249C2541998-06-24024 June 1998 Safety Evaluation Accepting Proposed Rev 19 to NNECO QAP Topical Rept & Amended Through 980609.Informs That NNECO Exception to Provisions in Paragraph 10.3.5 of Constitutes Temporary & Acceptable Alternative ML20248J0031998-06-0404 June 1998 Safety Evaluation Accepting Millstone Nuclear Power Station Emergency Plan ML20248M2991998-06-0202 June 1998 Safety Evaluation Approving Application Re Restructuring of Central Maine Power Co by Establishment of Holding Company ML20248C4131998-05-26026 May 1998 SER of Individual Plant Exam of External Events Submittal on Millstone Nuclear Power Station,Unit 3 ML20217M4181998-04-30030 April 1998 Suppl Safety Evaluation Accepting Licensee RCS Pressure & Heat Removal by Containment Heat Removal Sys post-accident Monitoring Instrumentation ML20216G7921998-03-13013 March 1998 Safety Evaluation Authorizing Proposed Alternative to Check Valve Obturator Movement Requirements of OM-10 for SIL Accumulator Outlet for Listed Check Valves ML20203E8521998-02-17017 February 1998 SER Accepting Request for Relief from Requirements of 10CFR50.55a(f) for Performing Required Inservice Testing of Certain Class 2 Components IAW ASME Boiler & Pressure Vessel Code Section XI for Plant,Unit 3 ML20203E9341998-02-17017 February 1998 SER Accepting Request for Relief from Requirements of 10CFR50.55a(g) for Performing Required Exams for Certain Class 1 Components IAW ASME Boiler & Pressure Vessel Code Section XI for Plant,Unit 3 ML20203E2441998-02-0909 February 1998 Safety Evaluation Accepting Re Approval of Realistic,Median Centered Spectra Generated for Resolution of USI-A-46 ML20198R9941998-01-13013 January 1998 SER Accepting Licensee Response to GL 95-07, Pressure Locking & Thermal Binding of Safety-Related Power-Operated Gate Valves, for Millstone Nuclear Power Station,Unit 3 ML20202H7461997-12-10010 December 1997 Safety Evaluation Accepting Licensee Position That Correction of AC-11 Single Failure Vulnerability Unncessary ML20202J0911997-12-0202 December 1997 Safety Evaluation Accepting Proposed Exemption,Which Meets Special Circumstance Given in 10CFR50.12(a)(2)(ii) ML20198S2411997-10-31031 October 1997 SE Accepting Licensee Request for Deviations from Recommendations in Reg Guide 1.97,Rev 2 for Temp & Flow Monitoring Instrumentation for Cooling Water to ESF Sys Components & Containment Isolation Valve Position ML20212G5991997-10-27027 October 1997 Safety Evaluation Supporting Amend 103 to License DPR-21 ML20217K8801997-10-27027 October 1997 Correction to Safety Evaluation Supporting Amend 103 to License DPR-21.Phrase or Rod Block Protection Has Been Deleted from Listed Sentence in Staff Associated SE ML20212F1381997-10-22022 October 1997 Safety Evaluation Supporting Amend 102 to License DPR-21 ML20217M9301997-08-19019 August 1997 Safety Evaluation Accepting Continued Operation W/O High Startup Rate Trip by Nene for Millstone,Unit 2 ML20149J2661997-07-23023 July 1997 Safety Evaluation Accepting Changes & Reanalyses in ECCS Evaluation Models & Application of Models for Plant,Unit 2 ML20141L8821997-05-28028 May 1997 Safety Evaluation Supporting Amend 101 to License DPR-21 ML20138A0111997-04-23023 April 1997 Safety Evaluation Accepting Licensee Proposal,Not to Perform Type C Leakage Rate Testing on 14 Subject CIVs ML20137V5931997-04-15015 April 1997 Safety Evaluation Supporting Amend 100 to License DPR-21 ML20137U3121997-04-10010 April 1997 Safety Evaluation Supporting Amends 99,206 & 135 to Licenses DPR-21,DPR-65 & NPF-49,respectively ML20134A0331997-01-23023 January 1997 Safety Evaluation Accepting Util Proposed Alternatives to ASME Code Requirements ML20133N3401997-01-14014 January 1997 Safety Evaluation Supporting Amend 98 to License DPR-21 ML20135C4221996-12-0202 December 1996 Safety Evaluation Accepting Proposed Alternative Described in Relief Request R-1 Re Valve Inservice Testing Program at Facility ML20128P4381996-10-0909 October 1996 Safety Evaluation Accepting Review of Cracked Weld Operability Calculations & Staff Response to NRC Task Interference Agreement ML20128L7541996-10-0404 October 1996 Safety Evaluation Supporting Amend 97 to License DPR-21 ML20248C5451995-05-0202 May 1995 SER on Millstone Unit 3 Individual Plant Exam of External Events to Identify plant-specific Vulnerabilities,If Any,To Severe Accidents & Rept Results Together W/Any licensee-determined Improvements & C/A to Commission ML20248C5731994-07-19019 July 1994 SER Step 1 Review of Individual Plant Exam of External Fire Events for Millstone Unit 3 ML20059H4991994-01-24024 January 1994 Safety Evaluation Accepting Revised Responses to IEB-80-04 Re MSLB Reanalysis 1999-08-30
[Table view] Category:TEXT-SAFETY REPORT
MONTHYEARML20217P5391999-10-25025 October 1999 Rev 0,Change 1 to Millstone Unit 1 Northeast Utils QA Program ML20217C8721999-10-0606 October 1999 Rev 21,change 3 to MP-02-OST-BAP01, Nuqap Topical Rept, App F & G Only B17896, Monthly Operating Rept for Sept 1999 for Millstone Nuclear Power Station,Unit 1.With1999-09-30030 September 1999 Monthly Operating Rept for Sept 1999 for Millstone Nuclear Power Station,Unit 1.With B17894, Monthly Operating Rept for Sept 1999 for Millstone Nuclear Power Station,Unit 2.With1999-09-30030 September 1999 Monthly Operating Rept for Sept 1999 for Millstone Nuclear Power Station,Unit 2.With B17898, Monthly Operating Rept for Sept 1999 for Millstone Nuclear Power Station,Unit 3.With1999-09-30030 September 1999 Monthly Operating Rept for Sept 1999 for Millstone Nuclear Power Station,Unit 3.With ML20216J4341999-09-24024 September 1999 Mnps Unit 3 ISI Summary Rept,Cycle 6 ML20211N8401999-09-0202 September 1999 Rev 21,change 1 to Northeast Utils QA TR, Including Changes Incorporated Into Rev 20,changes 9 & 10 B17878, Monthly Operating Rept for Aug 1999 for Mnps,Unit 1.With1999-08-31031 August 1999 Monthly Operating Rept for Aug 1999 for Mnps,Unit 1.With B17874, Monthly Operating Rept for Aug 1999 for Millstone Nuclear Power Station,Unit 3.With1999-08-31031 August 1999 Monthly Operating Rept for Aug 1999 for Millstone Nuclear Power Station,Unit 3.With ML20216F5141999-08-31031 August 1999 Rept on Status of Public Petitions Under 10CFR2.206 B17879, Monthly Operating Rept for Aug 1999 for Millstone Nuclear Power Station,Unit 2.With1999-08-31031 August 1999 Monthly Operating Rept for Aug 1999 for Millstone Nuclear Power Station,Unit 2.With ML20211G9631999-08-30030 August 1999 SER Accepting Licensee Response to GL 96-05, Periodic Verification of Design-Basis Capability of Safety-Related Motor-Operated Valves ML20211A6561999-07-31031 July 1999 Monthly Operating Rept for July 1999 for Millstone Nuclear Power Station,Unit 2 B17858, Monthly Operating Rept for July 1999 for Millstone Nuclear Power Station,Unit 3.With1999-07-31031 July 1999 Monthly Operating Rept for July 1999 for Millstone Nuclear Power Station,Unit 3.With B17856, Monthly Operating Rept for July 1999 for Millstone Nuclear Power Station,Unit 1.With1999-07-31031 July 1999 Monthly Operating Rept for July 1999 for Millstone Nuclear Power Station,Unit 1.With ML20210J0311999-07-21021 July 1999 Rev 20,Change 10 to QAP 1.0, Organization ML20210E5931999-07-19019 July 1999 Revised Page 16 of 21,to App F of Northeast Util QA Program Plan ML20210C5911999-07-15015 July 1999 Revised Rev 20,change 10 to Northeast Util QA Program TR, Replacing Summary of Changes ML20210A0411999-07-15015 July 1999 Rev 20,change 10 to Northeast Util QA Program Tr B17814, Special Rept:On 990612 B Train EDG Failed to Restart within 5 Minutes Following Completion of 18 Month 24 H Endurance Run Required by TS 4.8.1.1.2.g.7.Caused by Procedural inadequacy.Re-performed Hot Restart Via Manual Start1999-07-12012 July 1999 Special Rept:On 990612 B Train EDG Failed to Restart within 5 Minutes Following Completion of 18 Month 24 H Endurance Run Required by TS 4.8.1.1.2.g.7.Caused by Procedural inadequacy.Re-performed Hot Restart Via Manual Start ML20209D1881999-07-0101 July 1999 Rev 20,change 9 to Northeast Util QA Program Tr ML20196J2191999-06-30030 June 1999 SER Concluding That Licensee USI A-46 Implementation Program,In General,Met Purpose & Intent of Criteria in GIP-2 & Staff Sser 2 for Resolution of USI A-46 ML20211A6751999-06-30030 June 1999 Revised Monthly Operating Rept for June 1999 for Millstone Nuclear Power Station,Unit 2,providing Revised Average Daily Unit Power Level & Operating Data Rept ML20196A8451999-06-30030 June 1999 Post Shutdown Decommissioning Activities Rept ML20209J0541999-06-30030 June 1999 Monthly Operating Rept for June 1999 for Millstone Unit 2 B17830, Monthly Operating Rept for June 1999 for Millstone Nuclear Power Station,Unit 3.With1999-06-30030 June 1999 Monthly Operating Rept for June 1999 for Millstone Nuclear Power Station,Unit 3.With ML20196K1791999-06-30030 June 1999 Addendum 6 to Millstone Unit 2 Annual Rept, ML20196J1821999-06-30030 June 1999 Rev 21,Change 0 to Northeast Utilities QAP (Nuqap) Tr B17833, Monthly Operating Rept for June 1999 for Millstone Power Station,Unit 1.With1999-06-30030 June 1999 Monthly Operating Rept for June 1999 for Millstone Power Station,Unit 1.With ML20195H1011999-06-11011 June 1999 Rev 20,change 8 to Northeast Utilities QAP (Nuqap) TR ML20207G6411999-06-0303 June 1999 Safety Evaluation Supporting Amends 105,235 & 171 to Licenses DPR-21,DPR-65 & NPF-49,respectively ML20211A6631999-05-31031 May 1999 Revised Monthly Operating Rept for May 1999 for Millstone Nuclear Power Station,Unit 2,providing Revised Average Daily Unit Power Level,Operating Data Rept & Unit Shutdowns & Power Reductions B17808, Monthly Operating Rept for May 1999 for Millstone Nuclear Power Station,Unit 3.With1999-05-31031 May 1999 Monthly Operating Rept for May 1999 for Millstone Nuclear Power Station,Unit 3.With ML20211B7351999-05-31031 May 1999 Cycle 7 Colr B17804, Monthly Operating Rept for May 1999 for Mnps,Unit 2.With1999-05-31031 May 1999 Monthly Operating Rept for May 1999 for Mnps,Unit 2.With B17807, Monthly Operating Rept for May 1999 for Mnps,Unit 1.With1999-05-31031 May 1999 Monthly Operating Rept for May 1999 for Mnps,Unit 1.With ML20209J0661999-05-31031 May 1999 Revised Monthly Operating Rept for May 1999 for Millstone Unit 2 ML20206M4631999-05-11011 May 1999 Safety Evaluation Supporting Alternative Proposed by Licensee to Perform Ultrasonic Exam on Inner Surface of Nozzle to safe-end Weld ML20206J8351999-05-0707 May 1999 Rev 20,Change 7 to QAP-1.0, Northeast Utls QA Program (Nuqap) Tr ML20206G6221999-05-0404 May 1999 SER Accepting Util Request to Apply leak-before-break Status to Pressurizer Surge Line Piping for Millstone Nuclear Power Station,Unit 2 B17782, Monthly Operating Rept for Apr 1999 for Millstone Nuclear Power Station,Unit 1.With1999-04-30030 April 1999 Monthly Operating Rept for Apr 1999 for Millstone Nuclear Power Station,Unit 1.With ML20205R3531999-04-30030 April 1999 Addendum 4 to Annual Rept, B17775, Monthly Operating Rept for Apr 1999 for Millstone Nuclear Power Station Unit 3.With1999-04-30030 April 1999 Monthly Operating Rept for Apr 1999 for Millstone Nuclear Power Station Unit 3.With ML20205K6141999-04-30030 April 1999 Non-proprietary Version of Rev 2 to Holtec Rept HI-971843, Licensing Rept for Reclassification of Discharge in Millstone Unit 3 Spent Fuel Pool ML20206E2971999-04-30030 April 1999 Rev 1 to Millstone Nuclear Power Station,Unit 2 COLR - Cycle 13 B17777, Monthly Operating Rept for Apr 1999 for Millstone Unit 2. with1999-04-30030 April 1999 Monthly Operating Rept for Apr 1999 for Millstone Unit 2. with ML20205Q5891999-04-0909 April 1999 Rev 20,change 6 to QAP-1.0,Northeast Utils QA Program TR ML20205R8751999-04-0909 April 1999 Provides Commission with Staff Assessment of Issues Related to Restart of Millstone Unit 2 & Staff Recommendations Re Restart Authorization for Millstone Unit 2 ML20206T3991999-03-31031 March 1999 First Quarter 1999 Performance Rept, Dtd May 1999 B17747, Monthly Operating Rept for Mar 1999 for Millstone Nuclear Power Station,Unit 1.With1999-03-31031 March 1999 Monthly Operating Rept for Mar 1999 for Millstone Nuclear Power Station,Unit 1.With 1999-09-30
[Table view] |
Text
.
,OFFHCHAL USE ONLY Docket No. 50-245 December 24, 1969 Supplemental Report to ACRS MILLSTONE NUCLEAR POWER STATION UNIT 1 1
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1.0 INTRODUCTION
AND
SUMMARY
In our report to the ACRS, dated November 24, 1969, containing the results of our safety evaluation of the Millstone Unit 1 facility, we indicated that we would report orally on certain matters. These matters, referenced to the applicable section of our initial report, are as follows:
- Site flooding potential (Section 3.3)
- Inservice inspection program with regard to the recirculation nozzle welds and the vessel support skirt (Section 5.4)
- Adequacy of analytical methods used for the seismic design of the f acility including Class I piping (Section 6.1)
- Instrumentation and control items consisting of single failure protection for auto-relief interlock and containment spray system control; monitoring capability of Target Rock relief / safety valve bellows integrity; design apn11 cation of the single f ailure criterion; and indenendency provisions for the standby gas treatment system (Section 8.4)
- Turbine building secondary closed cooling water system (Cection 9.3)
These matters have been further discussed with the applicant, and addi-tional information was provided in Amendment Nos. 21 and 22, dated December 5 and December 19, 1969, respectively. This additional informa-tion has been reviewed and our evaluation is presented in this report.
Our review of the Millstone Unit 1 Technical Specifications is continuing and the draft proposed by the applicant (Amendment No. 20) has been CFFHCHAL USE ONLY ~
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. OFFHCHAL USE ONLY-provided to the Committee. Subject to development of final Technical l Specifications and satisfactory completion of construction and preopera-tional tests, we conclude that Unit 1 may be licensed for operation.
2.0 DISCUSSION 2.1 Site Flooding Potential As indicated in our initial report, the applicant has performed analysis of flooding at the site due to the probable maximum hurricane. The entire structural periphery of the Unit 1 facility is protected to an elevation ,
of +19 f eet MSL by reinforced concrete walls topped of f by 2-inch-angle iron. All external entrant.es are provided with rubber sealed flood gates to this elevation. Data provided by the applicant indicate that the probable maximum surge water level would not exceed +16 feet MSL; how-ever, our consultant on this matter, Coasts 1 Engineering Research Center (CERC) has estimated a maximum surge level of +18.2 feet MSL and wave runup of the order of 2.5 feet. This results in a maximum water elevation of +20.7 feet MSL according to the CERC model. The report from CERC has been provided to the Committee.
Although the applicant and its consultants consider the higher water i level event extremely unlikely, they have provided additional information on plant capability using the CERC model. The analysis predicts a maximum i
l- surge level below the level.to which the plant is protected but wave l
l l runup could possibly result in water seepage into portions of the facility .
/
l structures other than\the reactor buil ing, whi, , flood protected to L OFFHCHAL USE ONLY ~
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3 elevations well above +25 feet MSL. The applicant's study also indientes that safe shutdown can be accommodated and maintained since critical equipnent for such ection is protected to at lesst
+?S feet MSh. The critical equipment associated with such action '
is the teolation condenser, veter makeup and diesel generator.
- We conclude that the level of flood protection pr'ovided for Unit 1 is acceptable in view of the plant capability for safe shutdown, even in the event of the low probability flood levels predicted by the CERC model.
2.2 Inservice Inspection Program In our initial report, we indicated that the applicant proposed not to include nozzle-to-vessel velds in the inlet an'd outlet recireuta.
tion lines and the velds in the vessel support skirt in the inservice insrection program. Beesuse of the safety significance of breaks in the nozzle regions, and because the shield blocks and insulation are removable in the region of the nozzles, ve have concluded that the applicant should develop means to include'the nozzles in the inspection pro 6 ram. As in the Dresden 2 program, we vill include this inspection requirement in the Technteel Specifications.
Access to the support skirt velds is not presently available. The
[
applicant, however, proposes to study meana_e.n4Jo develop techniques for. remote inspection of this , veld regisq.. This action is stated in the bases to Technical Specification h.6 and is acceptable to es.:
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23 Adequecy of Analytical Methods Used in Seismie Design Additional information hos been provided by the applicant in Amendments 17,18,19 and 21 on stress levels in critics'. piping systems and on the analytical methods employed for dynamic analysis. The information has been found acceptable by Dr. Newmark, as discussed in his report which has beten provided to the Committee. We consider this matter to be resolved. .
2.h Instrumentation and Control Items 2.4.1 Containment Spray Control System Because of the heat exchanger especity of the containment cooling system,it is necessary that reliance be placed on containment pressure to assure adequate NPSH for the ECCS pumps. The Technical Specificatione ,
1 impose restrictions on torus veter temperature and on the operability of I the containment cooling system. - These actions' assure that the cooling cepscity would not degrade to a point where excessive- temperatures occur and complete relisnee on containment pressure is required for adequate-NPSH.
To give complete NPSH protection, inadvertent actuation of containment-sprey is -prevented and similarly the spray action is terminated +
, automatically when the containment pressure decreasts below a preset value.
The applicant has improved the design of this containment spray interlock -
to provide single failure protection against inadvertent spray actuation, but has not provided the'same single failure protection for the automatic !
termination of containment spray. However, manual termination of.sprey.
operation in possible and the manual control circuitry is designed to:
the single failure criterion. ,
- OFFEHAL USE OFLY
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In Amendaent No.16 (Figure D-1.h), the applicant shows that with two containment cooling leops in operation, ECCS pump NPSH require-ments are satisfied whether or not the containment sprays are in operation. As indicated in our initial report, we vill require the two containment cooling loops to be operable as a limiting condition of operation _
We conclude that the containmaa+ epeey-control-eyete- i= acrttgage. _
2.h.2 ECCS Lov Pressure Auto Relief Interlock The interlock function is provided by an arrangement involving six
, pressure switches (one switch for each ECCS pump) monitoring pump discharge pressure. The interlock is a permissive - type which allows initiation of auto-relief when one of the six switches responds to either the pressure characteristics or to a circuit failure which produces the same signet to the auto-relief system as the pressure characteristic. Therefore, a single failure which produces a permissive condition vould defeat the parpose of the interlock in cases when non-permissive circuit orientation is required. We believe that eingle feiture immunity is required for this particular design aspect.
The applicent has not agreed to this requirement. We plan to require that the design be modified to provide protection against this mode of failure.
2.4.3 Monitoring Canability of the Integrity of Bellows on the Target Rock Relief /Sefety Valves Beesuse the integrity of the bellows is essential to the self-actuated operating mode of the Terget Rock relief / safety valves, we conclude that the testing circuits associnted with bellows integrity monitoring e OFFHCHAL USE ONLY -
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1 should be l'aproved to effect unemby;uput, t e a t t ar.. 'i he " onl i ce nt
/> 'N r st*ted such c"nb111ty would be provided in the Millstone design, and
[c, we conclude that this is t eeeptable. We shall review the specific design detnil.s trier to issuance of an operating License to ensure th+ t these recuirements are satisfied.
2.h.h SinM e Failure criterton The a nMicent hat, stnted in Amendment 21 that the renetor protection and cont"Inment isointion systems ere designed to meet the single feiture criterion per IEEE 279 The ECCS is designed with protection eguinst effects of sinBle failures negating effective core cooling.
We conclude that this design is adequate.
- 2. l+ 5 Standby Ces Treatment System (SBGTS) tr Amendmen. 2l, the applicant indicated that the SBGTS would be designed to meet the single.feiture criterion but did not agree to completely satisfy lEEE 279, which was the original canmitment. Although the system contains ndequate physical and electrical separation the control instrumentotion of one equipment chnin is dependent on another; i.e. , onerotion of n redundant equipment chain is dependent upon the fniture of ito redundant counterpart for initiation and operation.
We bmve concluded that provision; should be med? to provide for independence of redundant control nnd initiatien circuitry and plan to require such action.
25 Turbine Building Secondary Closed Cooling Water System (TBSCCW)
As noted in our report, the TBSCCW system provides cooling for the ECCS l
upper pumo. motor benrings. We indicated to the applicant and GE that
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a failure of the TBSCCW system apparently could lead to a loss of cooling of the bearing lubrication oil. Subsequent overheating of the bearings could possibly result in total failure of all ECCS pump.
motors. In response, the applicant has p./oposed plant design changes that voo i n'... ide en alternate coolf ag system to the various ECCS pumps. Such action was stated in Amendment No. 21, along with a dis-cussion of several possible methods. Subsequent discu'ssions with the applicant were held and Amendment 22 describes the method to be employed-which consists of providing coolant to the ECCS pumps from the torus -
veter. This method of cooling is the same as that employed in ths Dresden 2/3, Oyster Creek and Nine Mile Point facilities. We conclude-that this arrangement is acceptable.
N -
30 Conclusions We and the applicant do not agree on actions taken regarding certain review areas. These matters are listed below along with a summary of our positions for the C~nmittee's reference.
. Containment-Cooling System-(Section 7 5 of initial report)
Because of concern on NPSH and the small heat removal capacity,.
we consider that both containment cooling loops must be opgrable as a -limiting condition for continued planLoperation. -Minimum requirements for equipment operability (including plant emergency power systems) and. limitations on the time that equipment can:be out-of service for maintenance vill be included in the Technical Spe cifica tions.
l
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4FFRCHAL USE ONLY s
- 8-Inservice Inspection Program (Section 5 4 of initial report and 2.2 above)
We vill include the nozzle-to-vessel velds in the inlet and outlet recirculntion lines in the inservice inspection program.
- Auto Relief Interlock (Section 8.4.5 of initial report end 2.4.2 above)
We vill require that the interlock with regard to the pressure switches be made immune to the effects of single failures.
Standby Gas Treatment System (Section 8.4.8 of initial report end
~
2.4.5 above)
We vill require that provisions be made for independence of i
redundent control and initiation circuitry.
- Containment Inerting (Section 6.4 of initist report)
We vill require that the containment be inerted following comple-tion of the plant start p and power ascension test progrem.
If the actions indicated above are token, we corelude that Millstone Unit t can be operated without endangering the health and safety of the public.
i OC ", "f" w -i.s :.x w.a 'hMf sw- U t