IA-89-101, Informs of Completion of Review of Application by Niagara Mohawk Power Corp for Conversion of Util Provisional OL to full-term OL During ACRS 740905-07 Meeting.Concurs in Subj License Conversion

From kanterella
Jump to navigation Jump to search
Informs of Completion of Review of Application by Niagara Mohawk Power Corp for Conversion of Util Provisional OL to full-term OL During ACRS 740905-07 Meeting.Concurs in Subj License Conversion
ML20244E353
Person / Time
Site: Nine Mile Point Constellation icon.png
Issue date: 09/10/1974
From: Stratton W
Advisory Committee on Reactor Safeguards
To: Ray D
US ATOMIC ENERGY COMMISSION (AEC)
Shared Package
ML17055E652 List:
References
FOIA-89-101, FOIA-89-114 NUDOCS 8904240440
Download: ML20244E353 (3)
v • d • e


Text

_ _ _ - - - _ _ _ _ _ _ _ _ _. _ _ _ -

~

4 APPENDIX A

(

4 ADVISORY COMMITTEE ON REACTOR SAFEGUARDS N, UNITED STATES ATOMIC ENERGY COMMISSION ,,

wash NGTON. D.C. ROMB Q N

- u, September 10, 1974- S' q n

[ fi', m l - i3 a t p m Honorable Dixy Lee Ray p g ~~

l ' n N

Chairman O U. S. Atomic Energy Commission M*

15 Washington, D. C. 20$45 B -

-< =

Subject:

' REPORT ON NINE MILE.PolhT NUCLEAR STATION UNIT 1

Dear Dr. Ray:

l At its 173rd meeting, September 5-7, 1974, the Advisory Committee on Reactor Safeguards completed a review of the application by the Niagara Mohawk Power Corporation for conversion of its Nine Mile Point Nuclear Station Unit 1 provisional operating license to a full-term operating license. The'appli-

[j cation also was considered at a' Subconenittcc meeting in Washington, D. C. on July 29, 1974. During its review, the Corxalttec had the benefit of discus-g ( sf ons with representatives of the Niagara Mohawk Power Corporation, General J

i Electric Company, and the AEC Regulatory Staff. The Conraittcc also had the benefit of the documents listed. The Committee previously discussed' this j project in an operating license report of April 17, 1969 and in subsequent

" reports dated June 16, 1970 and February 6, 1971.

In its review, the Committee evaluated the operation and performance of this unit with particular emphasis on the rceponse of the applicant to

{ past recocunendations for improvements in safety related systems.

3 Unit 1 is a non-jet pump boiling water reactor of 1850 MW(t) rated power 1evel. Commercial power o, eration of the plant was begun in December,1969.

[ However, The operating history of the unit has been generally satisfactory.

a number of operating problems or design deficiencies have been encountered Included among during the approximately five year period of power operation.

these are: cracking of a core spray nozzle safe end; development of cracks in the steam dryer assembly; control rod ' scram sluggishness; failure of sone control rods to remain fully inserted after scram; increased control i rod operating restrictions found necessary to assure protection for a pos-j tulated rod drop accident; feedwater control deficiency, with resultant

' flooding of steam lines; torus baffic dislocation by relief valve steamAll discharge into the torus; and, failure of a relief valve to reclose. Reactor of these deficiencies appear to have been satisfactorily corrected.

availability has averaged approximately 667..

(

I 8904240440 890413 .

PDR FOIA WETTERH89-101 PDR; J

4

~

Honorable Dixy Lee Ray September 10, 1974 i  ;

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

, probabic low levels of residual stresses now existing in these valves, will' l

enable maintenance of acceptable leakage rates in the future. This matter

-! should be followed closely by the Regulatory Staff.

f A number of design improvements have been accomplished or comitted to since operation began. Among the most significant of these from the point of view of safety are the following. The feedwater system has been modified also to serve as ar, additional emergency core cooling system for small breaks; emergency power for this system is supplied by an of fsite source of hydro-clectric power. A fuel cask drop protection system has been designed and approved, and installation will be completed before shipment of spent fuct is, undertaken. A containment atmosphere dilution (CAD) system for combustibic l

gas control will be installed and availabic for operation in 1976. An ad-ditional primary pressure boundary leak detcetion system has been added, and position indication in the control room for the containment vacuum breaker valves has been provided.

l Approximately one-fifth of the reactor 7x7 fuel bundles have been replaced

} with 8x8 fuel; through additional reloads, the core eventually is to consist l J

( cntirely of 8x8 fuel.

{ 3

Because of the relatively limited accessibility for in-service inspection 1

of the reactor pressure vessel, the Comittee wishes to emphasize again its j

belief that additional means for assuring continued vessel integrity, in- i' l; i cluding possible improvement in accessibility, should continue to be actively

( o studied and impicmented to the degree practical.

l The Comittee recomends that the Regulatory Staff and the applicant give

] further consideration to the possible advisability of additional backfitting

' of Unit 1 where significant and practical safety improvements can be 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 coments and those in previous ACRS reports on p

- this plant, there exists reasonable assurance that the Nine Mile Point Nucicar Station Unit 1, can continue to be operated at power levcis up to 1850 MW(t) without undue risk to the bestth and safety of the public. The

! Committee concurs in conversion of the present provisional operating license

. to a full-term operating license. .

f Sincerely yours, 5

l

/)y f M 1 1

.L l(

l W. R. Stratton ,

Chairman l'

References:

Sec Page 3

___ ___________.__.___m..__m_ -

~ ~

]

. Eo.norable Dixy Lee Ray , ,,

September 10, 1974 I .

References

1. Niagara Mohawk Power Company Technical Supplement to Petition for Conversion from Provisional Operating License to Full-Term Operating License dated July 1972.

).

\b 2. Applicant's Environmental Report, Operating License Stage, Conversion

/l to Full-Tero Operating License, June 1972.

l

3. Amendments 1 through 3 to Application for Full-Term Operating License.

i

4. Directorate of Licensing Safety Evaluation Report dated July 3, 1974
5. Directorate of Licensing letter dated July 3,1974 concerning list of f 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 j t

Transients and Postulated Loss-of-Coolant Accident.

f <

(

([. .

l[ I t

~

1 i

,i e

4 t

M

( e t

0 9

a--__-_-____-____ . _ _ - _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _

Retrieved from "https://kanterella.com/w/index.php?title=IA-89-101,_Informs_of_Completion_of_Review_of_Application_by_Niagara_Mohawk_Power_Corp_for_Conversion_of_Util_Provisional_OL_to_full-term_OL_During_ACRS_740905-07_Meeting.Concurs_in_Subj_License_Conversion&oldid=3213424"