ML20215N796
| ML20215N796 | |
| Person / Time | |
|---|---|
| Site: | Millstone  |
| Issue date: | 10/29/1986 |
| From: | Thadani A Office of Nuclear Reactor Regulation |
| To: | |
| Shared Package | |
| ML20215N797 | List: |
| References | |
| TAC-63133, TAC-63198, NUDOCS 8611070282 | |
| Download: ML20215N796 (9) | |
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7590-01 UNITED STATES NUCLEAR REGULATORY COMMISSION NORTHEAST NUCLEAR ENERGY COMPANY, ET AL.
DOCKET NO. 50-336 NOTICE OF CONSIDERATION OF ISSUANCE OF AMENDMENT TO FACILITY OPERATING LICENSE AND PROPOSED NO SIGNIFICANT HAZARDS CONSIDERATI0N DETERMINATION AND OPPORTUNITY FOR HEARING The 'U.S. Nuclear Regulatory Commission (the Commission) is considering
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issuance of an amendment to-Facility Operating License No. DPR-65, issued; to' Northeast Nuclear Energy Company (the licensee'), for operation of the
. Millstone Nuclear Power Station,. Unit No. 2, located in New London County, Connecticut.
By applications for: license amendments dated October 20, October 24 and October 27, 1986', the' licensee requested changes to the Technical O
Specifications (TS) for Millstone Unit No. 2.
The proposed changes to the
. TS provide for:
(1) revised temperature pressure limits in TS 3/4.4.9,
" Pressure / Temperature Limits" and TS Figure 3.4-2, " Reactor Coolant System Pressure Temperature Limitations for 12 Full Power Years," (2) a change to the surveillance frequency for determining reactor coolant system (RCS) flow rate in TS 4.2.6, "DNB Margin," and (3) changes to several TS associated with RCS flow and reactor power peaking limits.
Before issuance of the proposed license amendment, the Commission will have made findings required by the Atomic Energy Act of 1954, as amended (the Act) and the Commission's regulations.
The Commission has made a proposed determination that the amendment request involves no significant hazards consideration.
Under the Commission's regulations in 10 CFR 50.92, this means that operation of the facility in 8611070282 861103 PDR ADOCK 05000336 p
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i accordance with the proposed amendment would not (1) involve a significant increase in the probability or consequences of an accident previously evaluated; or (2) create the possibility of a new or different kind of accident from any accident previously evaluated; or (3) involve a significant reduction in a margin of safety.
The October 20, 1986 application for license amendment proposes revised temperature / pressure limitations for the reactor pressure vessel that would
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be applicable to 12 effectlye full power years (EFPY).
The existing
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licitations in the TS are.only applicable up to 7 EFPY which will be reached
_sarly during Cycle 8 operation.
The reactor is presently in a' refueling outage in preparation for Cycle 8 operation.
Operation of the reactor vessel is restricted to safe pressures for a given temperature. Since exposure to radiation embrittles the vessel, the operating restrictions are modified over time.
To maintain a constant safety margin, either the maxinium allowable pressure for a given temperature is reduced or the maximum allowable rate of temperature change is modified.
The goal is to reduce the vessel stresses in recognition of the vessel's reduced resistance to brittle fracture.
In the case of the proposed TS, safety margin is maintained through a combination of proposed reduced heat-up and cooldown rates (maximum allowable rate of temperature change) in TS 3/4.4.9 and reduction in the maximum allowable pressure for a given temperature as shown in proposed TS Figure 3.4-2.
The proposed changes to TS 3/4.4.9 and TS Figure 3/4-2 do not involve a significant increase in the probability or consequences of accidents previously evaluated.
The requirements of TS 3/4.4.9 and TS Figure 3.4-2 are associated with preventing brittle fracture of the vessel and not with any e
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previously analyzed accident.
The proposed changes to the TS will not create
'the possibility of a new or different type of accident since the proposed limitations conservatively account for progressive vessel embrittlement to 12 EFPY; thus, operation within the limits of the proposed TS will preverit a brittle fracture of the reactor pressure vessel.
Finally, the proposed change to the TS will not involve a reduction in a safety margin.
As
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indicated previously, the proposed TS maintain the safety margin for reactor
'ves,s,el failure by increasing the restrictions on-reactor vessel temperature change rates and on minimum temperature at given pressures.
Accordingly, the Commission proposes to determine that the proposed changes to TS 3/4.4.9 and TS Figure 3.t-2 involve no significant hazards considerations.
The October 24, 1986 application for license amendment proposes a change i-to the RCS flow surveillance requirements of TS 4.2.5.2.
At the present time, RCS flow must be <fetermined every 12 hours1.388889e-4 days <br />0.00333 hours <br />1.984127e-5 weeks <br />4.566e-6 months <br />.
The licensee proposes that the' surveillance interval be increased to require RCS flow measurement every 31 days.
The measurement of RCS flow,_together with other measurements, is important to assure that the core thermal margins are sufficient.
In this regard, the departure from nucleate boiling (DNB) ratio is an important indicator of the reactor core thermal margin.
Significant changes in DN8 ratio due t'o RCS flow changes could result from two sources.
The first, type of flow related DNB change could result from the loss of one or more reactor coolant pumps.
This change would be dramatic and would result in the automatic shutdown of the reactor by the reactor protection system (RPS).
-The second* type of flow-related DNB change could result from the deposition
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. of corrosion products (crud) in the core.
Experience has shown that crud buildup, should it occur, is a long term problem that is manifested over several months.and thus would be observed over-several of the propose'd surveillance intervals.
Based upon the above, the proposed change to TS 4.2.5.2 does not involve a significant increase in the probability or consequences of accidents previously evaluated.
Accidents involving sudden RCS flow decreases are miAi, gated by the RPS and not by determination of RCS flow via TS.4.2.5.2.
3e proposed change to the TS does not create the possibility of a new or differ nt type of accident since no changes to equipment or operating modes are involved.
Finally, no safety margins would be significantly reduced.
The slow buildup of crud,, shop 1d it occur, would still be detected prior to any significant decrease _in DNBR. Accordingly, the Commission proposes to determine that the propo' sed change to TS 4.2.5.2. involves no significant haiardsconsiderations.
The October 27, 1986 application for license amendment proposes changes to the TS that would allow the reduction in the RCS flow rate from the
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current value of 350,000 GPM to 340,000 GPM.
Since the reduction in the RCS flow rate would reduce the DNB margin, a change is also proposed to reduce the total integrated radial peaking factor (Fr ).
The current value for F I8 r
1.565 for full power operation and is defined by TS Figure 3.2-3b for reduced power.
It is proposed to replace F with a 1.537 limit for full power r
operation and a more restrictive Figure 3.2-3b for reduced power levels.
The proposed change, therefore, is a trade-off of RCS flow for F The r.
following TS would change:
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- TS Figure 2.1-1, " Reactor Core Thermal Margin Safety Limit" - The o
indicated flow on this figure would be changed.
TS Table 2.2-1, " Reactor Protective Instrumentation Trip Setpoint o
Limits" - The setpoint for low RCS flow would be changed.
TS Figure 3.2-3b, " Total Radial Peaking Factor vs. Allowable Fraction o
of Rated Thermal Power" - This would be a revised curve.
TS 3.2.3, " Total Integrated Radial Peaking Factor - F " - The limit on
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T F
would be changed. -
7 o - TS Table 3.2-1, "DNB Margin" - The indicated RCS flow would be changed.
The licensee has provided a reanalysis of accidents and transients which could be-affected by the proposed change in RCS flow and F and has
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r determined that there ar'e no significant changes.in the analytic results.
Based upon the'above, the proposed changes to the TS do not involve a significant increase in the probability or consequences of an accident previously evaluated. 'EincethereductioninRCSflowratewillbeoffsetby a reduction in Fr, the Millstone Unit No. 2 design basis accidents are noti adversely affected.
The proposed TS changes will not create the possibility of a new or different kind of accident from any previously evaluated.
Because the change in RCS flow rate is offset by changes to the total integrated radial peaking factor, no new unanalyzed events are created.
~ Finally, the proposed TS changes do not involve a significant reduction in-a margin of safety.
The potential reduction in DNB margin which would be caused by a reduction in the RCS flow rate is offset by the reduction in Fr.
Accordingly, the Commission proposes to determine that the proposed changes to the TS do'not involve significant hazards considerations.
The Commission is seeking public comments on this proposed determination.
4 Any comments received within 30 days after the date of publication of this notice will be considered in making any final determination.
The Commission will not normally make a final determination unless it receives a request for a hearing.
Comments should be addressed to the Rules and Procedures Branch, Division of Rules and Records, office of Administration, U.S. Nuclear Regulatory Commission, Washington, D. C.
20555.
By December'4,1986 the licensee may file a request for a hearing with g
respect to issuance of the amendment to the subject facility operating license yd any person whose interest may be affected by this proceeding and who wishes to participate as a party in the proceeding must file a written petition for leave to intervene.,-Request for a hearing and petitions for leave to intervene shall be filed.'in accordance with the Commission's " Rules of
- Practice for Domestic Licensing Proceedings" in 10 CFR Part 2.
If a request for a hearing or petit.'ioh for leave to intervene is filed by the above date, the' Commission or an Atomic Safety and Licensing Board, designated by the Commission or by the Chairman of the Atomic Safety and Licensing Board Panel, will rule on the request and/or petition and the Secretary or the designated Atomic Safety and Licensing Board will issue a notice of hearing or an appropriate order.
As required by 10 CFR S2.714, a petition for leave to intervene shall set forthwith!particularitytheinterestofthepetitionerintheproceedingand how that interest may be affected by the results of-the proceeding.
The petition should specifically explain the reasons why intervention should be permitted With particular reference to the following factors:
(1) the nature of the petitioner's right under the Act to be made a party to the proceeding; e
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(2) the nature and extent of the petitianer's property, financial, or other interest in the proceeding; and (3) the possible effect of any order which may be entered in the proceeding on the petitioner's interest.
The petition should also identify the specific aspect (s) of the subject matter of the proceeding as to which petitioner wishes to intervene.
Any person who has filed a petition for leave to intervene or who has been admitted as a party may. amend the petition without requesting leave of the Board up to fifteen (15) days prior to the first prehearipg conference scheduled in the proceeding, but such an. amended petition must satisfy the specificity requirements described above.
Not later than fifteen (15) days prior to the first prehearing conference scheduled in the proceeding, a petitioner ~ shall file a supplement *) the petition to intervene wh.ich must include a list of the contentions which are sought to be litigated in the matter, and the bases for each contention set forth with reasonable specificity.
Contentions shall be limited to matters within the scope of the ' amen'dment under_ consideration.
A petitioner who fails to file such a supplement which satisfies these requirements with respect to' at least one contention will,not be permitted to participate as a party.
Those permitted to intervene become parties to the proceeding, subject to any, limitations in the order granting leave to intervene, and have the opportunity to participate fully in the conduct of the hearing, including the opportunity to present evidence and cross-examine witnesses.
If a hearing is requested, the Commission will make a final determination on the' issue of no significant hazards consideration.
The final determination will serve to decide when the hearing ~is held.
If th'e final determination is that the amendment request involves no significanl hazrrds consideration, the Commission may issue the amendment and
make it effective, notwith' standing the request for a hearing.
Any hearing held would take place after issuance of the amendment.
If the final determinat' ion is that the amendment involves a significant hazards consideration, any hearing held would take place before the issuance of any amendment.
Normally, the Commission will not issue the amendment until the expiration of the 30-day notice period.
However, should circumstances change during the' notice period such that, failure to act in a timely way would result, for example, in derating or shutdown of the facility; the Commission may issue the license amendment before the expiration of the 30-day notice period, provided that its final determination is that the amendment involves no significant hazards consideration.,The final determination will consider all public and State comments received.., Should the Commission take this action, it will publish a notice of issuance and provide for opportunity for a hearing after issuance.
The Commiss' ion expects that the need to take this action will occur very infrequently.
A request for a hear'ing or a petition'for leave to intervene must be filed with the Secretary of the Commission, U.S. Nuclear Regulatory Commission, Washington, D. C.
20555, Attention: Docketing and Service Branch, or may be delivered to the Commission's Public Document Room, 1717 H Street, N.W.,
Washington, D. C., by~the above date.
Where petitions are filed during the lastten(10)daysofthenoticeperiod,itisrequestedthatthepetitioner promptly so inform the Commission by a toll-free telephone call to Western l
Union at (800) 325-6000 (in Missouri (800) 342-6700).
The Western Union operator should be given Datagram Identification Number 3737 and the following message addressed to Ashok C. Thadani:
petitioner's name and telephone
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number; date petition was mailed; plant name; and publication date and page number of this FEDERAL REGISTER notice.
A copy of the petition should also be sent to the Office of the General Counsel-Bethesda, U.S. Nuclear Regulatory Commission, Washington, D.C.
20555, and to Gerald Garfield, Esq., Day, 8erry and Howard, One' Constitution Plaza, Hartford, Connecticut 06103, attorney for the licensee.
Nontimely filings of petitions for leave to intervene, amended petitions,
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supplemental petitions and/,or requests for hearing will not be entertained ab.sent a determination by the Commission, the presiding officer or the Atomic S_jifety and Licensing Board, that the petition and/or request should be granted basegt upon a balancing of the' factors specified in 10 CFR 2.714(a)(1)(i)-(v)
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and 2.714(d).
For further details'with respect to this action, see the applications for l-amendments dated October 20, October 24 and October 27, 1986, which are available for public inspection at the Commission's Public Document Room, 1717 H Street, N.W., Washington, D.C., and at the Waterford Public Library,-
49 Rope Ferry Road, Water' ford, Connecticut 06103.
Dated at Bethesda, Maryland, this October 29, 1986.
FOR THE NUCLEAR REGULATORY COMMISSION
/f7 Ashok. Thadani, Director PWR P oject Directorate #8 Division of PWR Licensing-B e
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