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| number = ML17037C477
| number = ML17037C477
| issue date = 11/15/1974
| issue date = 11/15/1974
| title = Nine Mile Point, Unit 1 - Letter Enclosing Supplement No. 1 to the Safety Evaluation Report for the Application for a Full-Term Operating License
| title = Letter Enclosing Supplement No. 1 to the Safety Evaluation Report for the Application for a Full-Term Operating License
| author name = Lear G
| author name = Lear G
| author affiliation = US Atomic Energy Commission (AEC)
| author affiliation = US Atomic Energy Commission (AEC)
| addressee name = Raymond P D
| addressee name = Raymond P
| addressee affiliation = Niagara Mohawk Power Corp
| addressee affiliation = Niagara Mohawk Power Corp
| docket = 05000220
| docket = 05000220
Line 13: Line 13:
| page count = 22
| page count = 22
}}
}}
=Text=
{{#Wiki_filter:November 15, 1974 DISTRIBUTION:
AEC PDR              DMuller Docket No. 50-220                                                                                          Local PDR            KRGoller Docket              TJCarter ORBi/3 Rdg          OIS (5 copies)
HJMcAlduff RBrodsky
                  .Niagara Mohawk Power Corporation                                                              SHanauer            CStephens                  (2 copies)
ATTN:    Mr., Philip D. Raymond                                                              AGiambusso          CJDeBevec Vice President  Engineering                                                        FSchroeder          SATeets 300 Erie Boulevard Hest                                                                        RBoyd (4      copies)                  NDube Syracuse, New York 13202                                                                      DKnuth (2 copies) 'Jones (2 cps)
RMaccary (2 copies) CLong Gentlemen:                                                                                    RTedesco (2 copies) RVollmer HDenton (2 copies) RSchemel The Directorate of Licensing has issued the enclosed Supplement                                                                          VBenaroya BGrimes No. 1 to the Safety Evaluation Report on your application for a                                                                                  GLainas SPawlicki full-tenn operating license for Unit                                    1    of your Nine Mile Point                                            TIppolito JKastner Nuclear Station.                                                                                                                                  SVarga JOsloond Sincerely,                                                                    RO (8)
TEnglehardt priginal Signed George Lear, Chief Operating Reactors Branch                            83 Directorate of Licensing
==Enclosure:==
Supplement No. 1 to Safety Evaluation Report cc:      See    next page p~-
EEE ATTACHED FOR OGC CONCURRENCE OF                                      -11/
                                                                                                                              /74 OPPICN~          ORB./(3..      ...........wWE>.dy....................oaaz3.......................                  L  AD./ORa...............c4PH:.....                W SVRHAMN~ EATR            . k4..... .........C JDeBayec,........GLear.              + ....................              KRGoller DATC ~    1/./+/Z4,....      llL....).5.'......D.4.....11L...)$          '......../.2.4    ..                  11/................../.74.................................
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Niagara:fohawk Power Corporation    2-                  November 15, 1974 cc: w/enclosure Hr. Arvin E. Upton, Esquire Le3oeuf, Lamb, Leiby 6 tfacRae 1757 N  Street,  N. U.
Washington, D. C. 20036 Hr. Robert P. Jones, Supervisor Town of Scriba R. D. 04 Oswego, New York    13126 Hiss Juanita I ersey, Librarian Oswego  City Library 120 E. Second Street Ommgo, New York 13126 Dr. Vill%am E. Seymour Staff Coordinator New York State Atomic Energy Council New York State Department of Commerce 99 Tfashington Street Albany,    New York 12210 OPRICE5H'VRHAMC~
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SUPPLEMENT NO. 1 TO THE SAFETY EVALUATION REPORT BY THE DIRECTORATE OF LICENSING U. S. ATOMIC ENERGY CO~QHSSION IN THE MATTER OF NIAGARA MOMtK POWER CORPORATION CONVERSION FROM PROVISIONAL OPERATING LICENSE TO FULL-TERM OPERATING LICENSE NINE MILE POINT UNIT 1 DOCKET NO. 50-220 NOVEMBER 15'' 1974
TABLE OF CONTENTS
: l. 0 INTRODUCTION 2.0  REPORT OF ADVISORY COMMITTEE ON REACTOR SAFEGUARDS  (ACRS) 2.,1  Main Steam Line  Isolation Valve Leakage 2.2  Reactor Pressure Vessel In-Service Inspection 2.3  Possible Additional Backfit Improvements 3.0  QUALITY ASSURANCE PROGRAM 4cO  CONCLUSIONS APPENDICES'PPENDIX A    Report of  ACRS
: 1. 0  INTRODUCTION The AEC  Regulatory    staff's    Safety Evaluation Report (SER), in the matter of the Niagara Mohawk Power Corporation (herein
                                      'I referred to  as  NMPC  or the licensee) application for conversion of Provisional Operating License        No. DPR-17  to  a  full-term I
operating license for Nine Mile Point Unit          1 (NMP-1) was    issued on  July 3, 1974. Copies of    this report  were made  available to the Advisory Committee on Reactor Safeguards            (ACRS  or Committee) to assist  it in its  review of this application.        The Committee completed  its  review of the licensee's application in September 1974 and  reported  its findings    to the Commission by letter dated. September 10, 1974.
2.0    REPORT OF THE ADVISORY COMMITTEE ON REACTOR SAFEGUARDS A copy  of the  ACRS  report to. the    Commission  is included's Appendix A. Me have considered      the comments and recommendations made by  the ACRS  in this report    and  the actions which    we have taken or  will'take relative to      these comments and recommendations are described in the following paragraphs.          The Committee identified three matters for further surveillance:            these matters consist of maintaining leak tightness of main steam line isolation valves; 'possible improvements in accessibility for in-service inspection of the reactor pressure vessel to assure continued vessel integrity;    and  consideration to the possible advisability of additional backfitting where significant          and  practical safety improvements can    be trade. The Committee concluded    that there
F exists reasonable assurance          that the Nine Mile Point Nuclear Station Unit      1 can  continue to be operated at power level's          .up to 1850    1%it without undue risk to the health          and  safety of the public.      Moreover, the Committee concurred        in conversion, of the present provisional operating license to a              full-term operating license.
2.1 Main Steam Line        Isolation Valve    Leaka e The Committee      indicated  its  awareness  of the    difficulty that      has been experienced        at EP-1 in maintaining the required leak tightness of the main steam line isolation valves (MSLIV)                and  stated that the Regulatory        staff  should continue to follow        this matter closely.
The  licensee stated        its belief  that leakage through these valves will be    maintained at acceptable rates below the Technical Specification limits        as a  result of  changes    in maintenance procedures involving the valve seats and plugs,                initiated during the 1974 refueling shutdown.          The next leakage      rate test of the
            'will be    performed during the 1975 refueling shutdown.
ll'SLIVs The Regulatory      staff will follow this mat'ter to confirm 'that the problem,    is corrected.                                                    l 2.2 Reactor Pressure Vessel In-Service Ins ection The Committee expressed        its belief that additional        means  for assuring continued vessel        integrity, including possible          improvement in accessibility for inspection, should continue to              be  actively studied and implemented to the degree practical.                The  licensee has  stated    its'interest to continue to      seek possible improvements in the matter of vessel acchssibility            and  to implement such
improvements to the degree          practical. Our on-going  review oi the operating      facility will monitor        progress in this area..
2.3  Possibl6 Additional Backfit Im rovements The Committee recommended          that the Regulatory staff    and  the  licensee'ive further consideration to additional backfitting          where  significant and  practical safety      improvements can be made.      The  licensee has indicated that        it has  a continuing program 'of review to determine the conCormance of RP-1 with new Regulat:ory Guides as these are issu'ed.'he Regulatory staff will continue its on-going review of
                                      ~ ~
RP-l, including consideration of backfitting where significant and,practical safety improvements            can be made.
,. 3.0    UALITY ASSURANCE ( A) PROGKQf As  stated in our      SER, we have    reviewed the licensee's    QA  Program and concluded      that    it is  acceptable. The licensee's  QA  Program was  described    in four different submittals.          This information              .was superseded    by the    licensee's submittal of August 28,'974, entitled, "Tenth Supplement to the Final Safety Analysis Report" which
        ,consolidates and unifies the earlier submittals.              We  have reviewed and determined      that the Tenth Supplement to the      FSAR  is the  same as  the    QA  Program which we had previously reviewed and found acceptable.
C 4:0  CONCLUSIONS Our  conclusions as stated in the Safety Evaluation Report remain unchanged..
C APPENDIX A ADYlSORY COMMlTTEE ON REACTOR SAFEGUARDS UNlTED STATES ATOMlC ENERGY COMMlSSlON VifASHlMkTOH, D.C:. 10545 nn September  10, 1974      ~
f7'>              a fl pJ    0fj I Honorable Dixy Lee Ray Chairman                                                                                        jul U. S. Atomic Energy Commission                                                    P3      CD D1 Mashington, D. C. 20545
==Subject:==
REPORT ON  NINE MILE. POINT NUCLEAR STATION        UN'
==Dear Dr. Ray:==
At  its  173rd meeting, September 5-7, 1.974, the Advisory Committee'on Reactor i
Safeguazds complete d a rev ew o f the application by the Niagara Mohawk Power Corporation for conversion o f itss Nine Mile Point Nuclear Station Vnit 1 provisiona 1 opera tin 1ng license c    to a full-tean ooerating l.icense. The app 1 1-  ~      ~
cation also was considered at a Subcommittee meeting in as ng on, July 29, 1974. During ltd review, the Committee had the benefit of discus-i sions with representat ves o f the Niagara Mohawk Power Corporation, General Electric Company, an d t hee AEC Regulatory Staff. The Committee also ha d tthee benefit oE the documents l.isted. The Committee              previous y iscusse project in an operating license report off Ap ri* 1 17 1969 and in subsequent xeports dated June 16, 1970 and Februazy 6, 1971.
In its    zev1ewp t h e C omm ittee evaluated the operation and performance of h'      t ith'rticular emphasis on the response of the app 1can o past recommendations for improvements in safety relate sys ems.
Un U  it 1 is anon-      e pump boiling water. reactor of 1850 ~M(t) rated power on-jet leve 1 . C ommexc1a 1 power operation of- the plant was begun 1n The operating h'is ory of  o the unit has been generally satisfactory.              However eratinng pro a number oof ooperat          roblems or design deficiencies have been encoun        ountezed during the approximately five year pexiod o =power opera ion.
these are: crac      1ng oof a ccoxe spray nozzle safe end; development o crac s rackin
.xn th e ssteam dryer assembly; contxol. rod scram s luugg1s        ishness.'failure i                of:
some conntzolzo r rods to remain fully inserted aEter scram, increased control.
xod'operating restrictions found necessary to assure p rotection for a pos-1    d    d dro accident. feedwatex contxol deficiency, with resultant oo 1ngoof ssteam lines; torus baffle dislocation b y xe floodin                                                            xelief valve steam discharge into the torus; and, fai        ure oof a relief valve to reclose, All failure of these deficiencies appear to have been satisfactorily coxrecte  ril  corrected. . Reactora availability has averaged approximately 667..
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                                                                '0 Honorable Dixy Lee Ray      .
September  10, 1974 Difficulty also      has been experienced in respect to repeated occurrences of excessive'leakage rates of the main steam isolation valves under 'test con-ditions. The applicant now proposes to remachine the valve seats and plugs to an improved configuration and believes that this, together with the probable low levels of residual stressesnow existing in these valves, wi'll enable maintenance of acceptable leakage rates "in the future'.        - This matter should be followed closely by the Regulatory Staff.                                  a A number    of design improvements have been accomplished or comnitted to since operation began. Among the most significant of these from the point of view of safety are the following. The feedwoter" system has been modified also to serve as an additional emergency core cooling system for small breaks; emergency power for this system is supplied by an offsite source of hydro-electric    power.'    fuel cask drop protection  system has been designed and approved,    and installation will be  completed  before  shipment of spent fuel is undertaken. A containment atmosphere dilution (CAD) system for combustible gas control will be installed and available for operation in 1976. An ad-ditional primary pressure boundary leak detection system has been added, and position'indication in the control room for the contaitunent vacuum breaker valves has been provided.
Approximately    one-fifth of the reactor 7x7 fuel bundles have been replaced with  8x8  fuel; through additional reloads, the core eventually is to consist entirely of,8x8 fuel.
Because    of the relatively limited accessibility for in-service inspection of the reactor pressure vessel, the Committee wishes to emphasize again its belief that additional means for assuring continued vessel integrity, in-cluding possible improvement in accessibility, should continue,to be actively studied 'and implemented to the degree practical.
The Committee recotrrnends    that the Regulatory Staff and the applicant give turther consideration to the possible advisability of additional backfitting of Unit 1 where s'ignificant and practical safety improvements can bc made.
The Committee believes that, in view of the      generally satisfactory operating experience to date and the 'improvements'made      in the plant'as noted herein, and subject to the above comments and -those      in previous ACRS reports on this plant, there exists reasonable assurance that the Nine Mile Point" Nuclear Station Unit 1, can continue to be operated at power levels up to 1850 MM('t) without undue risk to the health and safety of'he public. The Committee concurs in conversion of the present provisional operating license to a full-term operating license.
Sincerely yours, M. R. Stratton Choirman
==References:==
Sec Page 3
  ~
    ~ ~
        + )
e
                                                &3%
0    September 10. '974 Honorable Dixy Lee Ray References!
: 1. Niagara Mohawk Power Company Technical Supplement to Petition for Conversion from Provisional Operating, License to Full-Term Operating License dated July 1972.
: 2. Applicant'nvironmental Report, Operating License      Stage, Conversion to Full-Term Operating License, June 1972.
: 3. Amendments  1 through 3 to Application for Full-Term Operating License.
: 4. Directorate'f Licensing Safety Evaluation    Report dated July .3, 1974.
5~  Directorate of'icensing letter dated July    3, 1974 concerning list of outstanding items in  connection  with their review of application for Full-Term Operating License.
: 6. Niagara Mohawk Power Corporation letter dated November 20, 1972 con-cerning Fuel Densification and its Effect on Reactor Operation Including Transients and Postulated Loss-of-Coolant Accident.
4 ~}}

Latest revision as of 20:54, 4 February 2020

Letter Enclosing Supplement No. 1 to the Safety Evaluation Report for the Application for a Full-Term Operating License
ML17037C477
Person / Time
Site: Nine Mile Point Constellation icon.png
Issue date: 11/15/1974
From: Lear G
US Atomic Energy Commission (AEC)
To: Raymond P
Niagara Mohawk Power Corp
References
Download: ML17037C477 (22)


Text

November 15, 1974 DISTRIBUTION:

AEC PDR DMuller Docket No. 50-220 Local PDR KRGoller Docket TJCarter ORBi/3 Rdg OIS (5 copies)

HJMcAlduff RBrodsky

.Niagara Mohawk Power Corporation SHanauer CStephens (2 copies)

ATTN: Mr., Philip D. Raymond AGiambusso CJDeBevec Vice President Engineering FSchroeder SATeets 300 Erie Boulevard Hest RBoyd (4 copies) NDube Syracuse, New York 13202 DKnuth (2 copies) 'Jones (2 cps)

RMaccary (2 copies) CLong Gentlemen: RTedesco (2 copies) RVollmer HDenton (2 copies) RSchemel The Directorate of Licensing has issued the enclosed Supplement VBenaroya BGrimes No. 1 to the Safety Evaluation Report on your application for a GLainas SPawlicki full-tenn operating license for Unit 1 of your Nine Mile Point TIppolito JKastner Nuclear Station. SVarga JOsloond Sincerely, RO (8)

TEnglehardt priginal Signed George Lear, Chief Operating Reactors Branch 83 Directorate of Licensing

Enclosure:

Supplement No. 1 to Safety Evaluation Report cc: See next page p~-

EEE ATTACHED FOR OGC CONCURRENCE OF -11/

/74 OPPICN~ ORB./(3.. ...........wWE>.dy....................oaaz3....................... L AD./ORa...............c4PH:..... W SVRHAMN~ EATR . k4..... .........C JDeBayec,........GLear. + .................... KRGoller DATC ~ 1/./+/Z4,.... llL....).5.'......D.4.....11L...)$ '......../.2.4 .. 11/................../.74.................................

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Niagara:fohawk Power Corporation 2- November 15, 1974 cc: w/enclosure Hr. Arvin E. Upton, Esquire Le3oeuf, Lamb, Leiby 6 tfacRae 1757 N Street, N. U.

Washington, D. C. 20036 Hr. Robert P. Jones, Supervisor Town of Scriba R. D. 04 Oswego, New York 13126 Hiss Juanita I ersey, Librarian Oswego City Library 120 E. Second Street Ommgo, New York 13126 Dr. Vill%am E. Seymour Staff Coordinator New York State Atomic Energy Council New York State Department of Commerce 99 Tfashington Street Albany, New York 12210 OPRICE5H'VRHAMC~

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SUPPLEMENT NO. 1 TO THE SAFETY EVALUATION REPORT BY THE DIRECTORATE OF LICENSING U. S. ATOMIC ENERGY CO~QHSSION IN THE MATTER OF NIAGARA MOMtK POWER CORPORATION CONVERSION FROM PROVISIONAL OPERATING LICENSE TO FULL-TERM OPERATING LICENSE NINE MILE POINT UNIT 1 DOCKET NO. 50-220 NOVEMBER 15 1974

TABLE OF CONTENTS

l. 0 INTRODUCTION 2.0 REPORT OF ADVISORY COMMITTEE ON REACTOR SAFEGUARDS (ACRS) 2.,1 Main Steam Line Isolation Valve Leakage 2.2 Reactor Pressure Vessel In-Service Inspection 2.3 Possible Additional Backfit Improvements 3.0 QUALITY ASSURANCE PROGRAM 4cO CONCLUSIONS APPENDICES'PPENDIX A Report of ACRS
1. 0 INTRODUCTION The AEC Regulatory staff's Safety Evaluation Report (SER), in the matter of the Niagara Mohawk Power Corporation (herein

'I referred to as NMPC or the licensee) application for conversion of Provisional Operating License No. DPR-17 to a full-term I

operating license for Nine Mile Point Unit 1 (NMP-1) was issued on July 3, 1974. Copies of this report were made available to the Advisory Committee on Reactor Safeguards (ACRS or Committee) to assist it in its review of this application. The Committee completed its review of the licensee's application in September 1974 and reported its findings to the Commission by letter dated. September 10, 1974.

2.0 REPORT OF THE ADVISORY COMMITTEE ON REACTOR SAFEGUARDS A copy of the ACRS report to. the Commission is included's Appendix A. Me have considered the comments and recommendations made by the ACRS in this report and the actions which we have taken or will'take relative to these comments and recommendations are described in the following paragraphs. The Committee identified three matters for further surveillance: these matters consist of maintaining leak tightness of main steam line isolation valves; 'possible improvements in accessibility for in-service inspection of the reactor pressure vessel to assure continued vessel integrity; and consideration to the possible advisability of additional backfitting where significant and practical safety improvements can be trade. The Committee concluded that there

F exists reasonable assurance that the Nine Mile Point Nuclear Station Unit 1 can continue to be operated at power level's .up to 1850 1%it without undue risk to the health and safety of the public. Moreover, the Committee concurred in conversion, of the present provisional operating license to a full-term operating license.

2.1 Main Steam Line Isolation Valve Leaka e The Committee indicated its awareness of the difficulty that has been experienced at EP-1 in maintaining the required leak tightness of the main steam line isolation valves (MSLIV) and stated that the Regulatory staff should continue to follow this matter closely.

The licensee stated its belief that leakage through these valves will be maintained at acceptable rates below the Technical Specification limits as a result of changes in maintenance procedures involving the valve seats and plugs, initiated during the 1974 refueling shutdown. The next leakage rate test of the

'will be performed during the 1975 refueling shutdown.

ll'SLIVs The Regulatory staff will follow this mat'ter to confirm 'that the problem, is corrected. l 2.2 Reactor Pressure Vessel In-Service Ins ection The Committee expressed its belief that additional means for assuring continued vessel integrity, including possible improvement in accessibility for inspection, should continue to be actively studied and implemented to the degree practical. The licensee has stated its'interest to continue to seek possible improvements in the matter of vessel acchssibility and to implement such

improvements to the degree practical. Our on-going review oi the operating facility will monitor progress in this area..

2.3 Possibl6 Additional Backfit Im rovements The Committee recommended that the Regulatory staff and the licensee'ive further consideration to additional backfitting where significant and practical safety improvements can be made. The licensee has indicated that it has a continuing program 'of review to determine the conCormance of RP-1 with new Regulat:ory Guides as these are issu'ed.'he Regulatory staff will continue its on-going review of

~ ~

RP-l, including consideration of backfitting where significant and,practical safety improvements can be made.

,. 3.0 UALITY ASSURANCE ( A) PROGKQf As stated in our SER, we have reviewed the licensee's QA Program and concluded that it is acceptable. The licensee's QA Program was described in four different submittals. This information .was superseded by the licensee's submittal of August 28,'974, entitled, "Tenth Supplement to the Final Safety Analysis Report" which

,consolidates and unifies the earlier submittals. We have reviewed and determined that the Tenth Supplement to the FSAR is the same as the QA Program which we had previously reviewed and found acceptable.

C 4:0 CONCLUSIONS Our conclusions as stated in the Safety Evaluation Report remain unchanged..

C APPENDIX A ADYlSORY COMMlTTEE ON REACTOR SAFEGUARDS UNlTED STATES ATOMlC ENERGY COMMlSSlON VifASHlMkTOH, D.C:. 10545 nn September 10, 1974 ~

f7'> a fl pJ 0fj I Honorable Dixy Lee Ray Chairman jul U. S. Atomic Energy Commission P3 CD D1 Mashington, D. C. 20545

Subject:

REPORT ON NINE MILE. POINT NUCLEAR STATION UN'

Dear Dr. Ray:

At its 173rd meeting, September 5-7, 1.974, the Advisory Committee'on Reactor i

Safeguazds complete d a rev ew o f the application by the Niagara Mohawk Power Corporation for conversion o f itss Nine Mile Point Nuclear Station Vnit 1 provisiona 1 opera tin 1ng license c to a full-tean ooerating l.icense. The app 1 1- ~ ~

cation also was considered at a Subcommittee meeting in as ng on, July 29, 1974. During ltd review, the Committee had the benefit of discus-i sions with representat ves o f the Niagara Mohawk Power Corporation, General Electric Company, an d t hee AEC Regulatory Staff. The Committee also ha d tthee benefit oE the documents l.isted. The Committee previous y iscusse project in an operating license report off Ap ri* 1 17 1969 and in subsequent xeports dated June 16, 1970 and Februazy 6, 1971.

In its zev1ewp t h e C omm ittee evaluated the operation and performance of h' t ith'rticular emphasis on the response of the app 1can o past recommendations for improvements in safety relate sys ems.

Un U it 1 is anon- e pump boiling water. reactor of 1850 ~M(t) rated power on-jet leve 1 . C ommexc1a 1 power operation of- the plant was begun 1n The operating h'is ory of o the unit has been generally satisfactory. However eratinng pro a number oof ooperat roblems or design deficiencies have been encoun ountezed during the approximately five year pexiod o =power opera ion.

these are: crac 1ng oof a ccoxe spray nozzle safe end; development o crac s rackin

.xn th e ssteam dryer assembly; contxol. rod scram s luugg1s ishness.'failure i of:

some conntzolzo r rods to remain fully inserted aEter scram, increased control.

xod'operating restrictions found necessary to assure p rotection for a pos-1 d d dro accident. feedwatex contxol deficiency, with resultant oo 1ngoof ssteam lines; torus baffle dislocation b y xe floodin xelief valve steam discharge into the torus; and, fai ure oof a relief valve to reclose, All failure of these deficiencies appear to have been satisfactorily coxrecte ril corrected. . Reactora availability has averaged approximately 667..

~e C r

'0 Honorable Dixy Lee Ray .

September 10, 1974 Difficulty also has been experienced in respect to repeated occurrences of excessive'leakage rates of the main steam isolation valves under 'test con-ditions. The applicant now proposes to remachine the valve seats and plugs to an improved configuration and believes that this, together with the probable low levels of residual stressesnow existing in these valves, wi'll enable maintenance of acceptable leakage rates "in the future'. - This matter should be followed closely by the Regulatory Staff. a A number of design improvements have been accomplished or comnitted to since operation began. Among the most significant of these from the point of view of safety are the following. The feedwoter" system has been modified also to serve as an additional emergency core cooling system for small breaks; emergency power for this system is supplied by an offsite source of hydro-electric power.' fuel cask drop protection system has been designed and approved, and installation will be completed before shipment of spent fuel is undertaken. A containment atmosphere dilution (CAD) system for combustible gas control will be installed and available for operation in 1976. An ad-ditional primary pressure boundary leak detection system has been added, and position'indication in the control room for the contaitunent vacuum breaker valves has been provided.

Approximately one-fifth of the reactor 7x7 fuel bundles have been replaced with 8x8 fuel; through additional reloads, the core eventually is to consist entirely of,8x8 fuel.

Because of the relatively limited accessibility for in-service inspection of the reactor pressure vessel, the Committee wishes to emphasize again its belief that additional means for assuring continued vessel integrity, in-cluding possible improvement in accessibility, should continue,to be actively studied 'and implemented to the degree practical.

The Committee recotrrnends that the Regulatory Staff and the applicant give turther consideration to the possible advisability of additional backfitting of Unit 1 where s'ignificant and practical safety improvements can bc made.

The Committee believes that, in view of the generally satisfactory operating experience to date and the 'improvements'made in the plant'as noted herein, and subject to the above comments and -those in previous ACRS reports on this plant, there exists reasonable assurance that the Nine Mile Point" Nuclear Station Unit 1, can continue to be operated at power levels up to 1850 MM('t) without undue risk to the health and safety of'he public. The Committee concurs in conversion of the present provisional operating license to a full-term operating license.

Sincerely yours, M. R. Stratton Choirman

References:

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0 September 10. '974 Honorable Dixy Lee Ray References!

1. Niagara Mohawk Power Company Technical Supplement to Petition for Conversion from Provisional Operating, License to Full-Term Operating License dated July 1972.
2. Applicant'nvironmental Report, Operating License Stage, Conversion to Full-Term Operating License, June 1972.
3. Amendments 1 through 3 to Application for Full-Term Operating License.
4. Directorate'f Licensing Safety Evaluation Report dated July .3, 1974.

5~ Directorate of'icensing letter dated July 3, 1974 concerning list of outstanding items in connection with their review of application for Full-Term Operating License.

6. Niagara Mohawk Power Corporation letter dated November 20, 1972 con-cerning Fuel Densification and its Effect on Reactor Operation Including Transients and Postulated Loss-of-Coolant Accident.

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