ML20206E061
| ML20206E061 | |
| Person / Time | |
|---|---|
| Site: | Millstone  |
| Issue date: | 11/07/1988 |
| From: | Office of Nuclear Reactor Regulation |
| To: | |
| Shared Package | |
| ML20206E052 | List: |
| References | |
| NUDOCS 8811170382 | |
| Download: ML20206E061 (2) | |
Text
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SAFETY EVALUATION BY THE OFFICE OF NUCLEAR REACTOR RLGULATION RELATED TO AMENDMENT NO. n TOFACILIT)_OPERATINGLICENSENO.NPF-49 NORTHEAST NUCLEAR ENERGY COMPANY ET At..
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MILLSTONE NUCLEAR P0FER STAT 10N,,,0 NIT NO. 3 0
DOCKET NO. 50-423 I
INTRODUCTION i
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By Application for License Arendment dated Septer.ber 2, 1988 Northeast l
Nuclear Energy Corrpany (NNECO) proposed changes to the Millstone Unit 3 Technical Specifications (TS). The proposed opendn.ent would revise Technical 1
Specification Sections 4.7.3.1.6. 4.7.3.2.6 and the bases for TS 3/4.2.3 to require a 0.1 percent penalty to be added to Reactor Coolant System (RCS) flow neasurerent uncertainty values if the feedwater flow venturis are not cleaned at Itast orce every 18 trenths. This is to be done before the precision teat i
balance is perfomed to calibrate the reactor coolant flow rate indicators.
This change was necessary to incorporate an NRC staff concern addressed in the Safety Evaluation for Amendtrent No.17, the RTC byoass Manifold elimination.
l D I 5 C U S S 10,N, LN D,,Ey,A,L,0,A,T I,0 N On January 20,19PP, the NRC issued Anendrent No.12 to the Facility Operating 3
License fcr Millstone Unit No. 3. to the January 20, 1988 letter i
provided an evaluation of the licens6e's nethodology for detertinir,g l
RCS flow. One conponent of the overall RCS flow uncertainty i
is the uncertainty related to the condition of the feedwater flow sersing instrur.entation.
Since the feedwater flow venturi sensors are prone to i.
i fouling, overall RCS flow uncertainty say be increased by as ruch as 0.1% if i
such fouling is not corrected.
In the event that the feedwater flow venturi sensors cannot be inspected during refueling outages, it is conservative to i
l assume that fouling has occurred and that the increase of 0.1% for RCS flow uncertainty is applicable.
Regarding the effect of venturi fouling on RCS flow uncertainty, Enclosure 2 to the NRC staff's January 20, 19E8 letter concluded l
that:
"TS sections 4.2.3.1.6, 4.2.3.7.6 and the bases for TS section l
l 3/4.2.4[ sic](pageB3/42-E)willneedtoberodifiedtostate that the p m 1ty for undetected fouling of the feedwater venturis s f f '! will be added to the flow seasurtrent uncertainty iltes if the venturis are not cleaned. This is j
to be dene before the precisich heat baler.ce is made te calibrate
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the RCS flow rate indicator 5 (approxir.ately or.ce per 16 months),
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-T-The licensee has stated that the feehater venturis have beer.
cleaned for the Cycle 2 oparation.
The licensee has stated (Ref.10) that the above TS's will be rodified to reflect the requirement of 0.1% penalty if the venturis are not cleaned and submitted for NRC approval. The staff requires this rodification prior to Cycle 3 operation."
At the present tire. TS 4.2.3.1.6 requires that, in the event that the venturis are not inspected, the 0.1% uncertainty far. tor for RCS flow is imposed. No "cleaaing" requirement is contained in TS 4.2.3.1.6.
- However, the proposed change to TS 4.?.3.1.6 co'itains the cleaning requirerent. No sicitlar requirement is presently in TS 4.2.3.7.6.
The proposed change to TS 4.?.3.2.6, however, is identical to that proposed for TS 4.P.3.1.6.
The NRC staff has noted that the licensee's incorporation of the 0.1 percent penalty requirenent into the TS satisfies a Ifcensee cocrittrent docunented in the Acendrent No. I? Safety Evaluation.
Therefore, the staff finds the Ifcensee evaluation acceptable.
ENVIRCNVENTAL C0hSIDERA110N This amendaent changes a requirement with respect to insta11atien or use of a facility cocpor.ent located within the ristricted area as defir.ed in 10 CFR Part 20. The staff has deterrnined that the anendnent involves to significant increase in the arounts, and no significant change in the i
types, of any effluents that nay be released offsite, and that there is 1
to significant increase in irdividual or curulative occupational radiation exposure. The Cenissier has previously published a proposed finding that the arendnent involves no significant hazards consideration and there has been no public ccuent on such finding. Accordingly, the arend-1 nent rests the eligibility criteria for categorical exclusion set forth in 10 CFR 51.22(c)(9). pursuant to 10 CFR 51.22(b), no environcental inpact staten.ent or environnental assessrent need be prepared in connection with the issuance of the anendrent.
CONCLUSION l
We have concluded, based on the considerations discussed above, that (1) 1 there is reasonable assurance that the health and safety of the public will not be endangered by operation in the presosed manner, and (2) such activities will be conducted in ccepliance wit 1 the Ccer11ssion's i
regulations, and the issuance of the anendeent will not be inimical to I
i the cortron defense and security or to the health and safety of the' t
public.
Dated: November 7, 1988 Principal Contributor:
G. S. Barbor l
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