ML20059K756
| ML20059K756 | |
| Person / Time | |
|---|---|
| Site: | Davis Besse  |
| Issue date: | 09/05/1990 |
| From: | Hannon J Office of Nuclear Reactor Regulation |
| To: | |
| Shared Package | |
| ML20059K760 | List: |
| References | |
| NUDOCS 9009240231 | |
| Download: ML20059K756 (5) | |
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U.S. NUCLEAR REGULATORY COMISSION TOLEDO EDIS0N COMPANY A!LD THE CLEVELAND ELECTRIC ILLUMINATING COMPANY, DOCKET NO. 50-346 ENVIRONMENTAL ASSESSMENT AND FINDINGOFNOSIGNIFICANTIMPACJ The U. S. Nuclear Regulatory Commission (the Connission) is considering issuance of an amendment to Facility Operating License No. NPF-3, issued to ToledoEdisonCompanyandTheClevelandElectricIlluminatingCompany(the licensees), for operation of the Davis-Besse Nuclear Power Station, Unit No.
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I located in Ottawa County, Ohio.
ENVIRONMENTAL ASSESSMENT Identification of Propossd Action The proposed amendment would revise the provisions in the Technical-Spccifications(TS's)relatingtoincorporationofASMESectionIII,1971 Edition,coderequirementsfortheMainSteamSafetyValves'(MSSV's) i
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setpoints versus citing specific setpoints for each of the MSSVs in ac-cordance with Toledo Edison Company's application dated March 4, 1988 and supplemented by letters dated May 4 and December 6, 1988.
Specifically, the proposed amendment would:
(1) revise the Technical Specification Basis 3/4.7.1.1 to reflect the AS6e Section 111, 1971 Edition code requirements and how they are met; i
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(2) revise Technical Specification 3.7.1.1 to incorporate the ASME Section III, 1971 Edition code requirements by specifying a) a min w m of two OPERABLE safety valves per steam generator, at least one with a setpoint not greater than 1050 psig
(+/-1%),and b) a maximum setpoint of 1100 psig (+/-1%) for any OPERABLE safety valve.
(?) modify Technical Specification Table 4.7-1 to reflect:
2 lower capacity (583,574 lb/hr or approximately 5% rated capacity) MSSVs with lift sen hg at 1050 psig (11%.);
7 higher capacity (ts45,759 lb/hr or approximately 7% rated capacity) MSSVs with lift setting at 1700 psig (11%);
(4) delete Technical Specification Table 4.7-1, " Main Steam Line Safety Valve lift Settings";
(5) remove the reference to Table 4.7-1 from the Technical Specification Surveillance Requirement 4.7.1.1; (6) revis, ' <chnical Specification 3.7.1.1 to specify that the Hirh Flux Trip Setpoint is redu ed per Equation 3.7-1; (7) delete Technical Specification Table 3.7-1, " Maximum Allowable High Flux Trip Setpoint with Inoperab'e Steam Line Safety Valves";
(8) revise the Technical Specification Basis 3/4 7.1.1 to facorp'...e Equation 3.7-1 and its graphic representation for the Reduced High Flux 1.ip Setpoint.
Items (1), (2) and (3) have been amended through Amendment Numbers 117 (TAC No. 67394) dated August 24, 1988.
Items (4) through (8) tre addressed by the current amendment (TAC No. 68250).
I The Need for the Proposed Action I
The proposed changes are needed to support greater flexibility in the i
requirements for valve set pressure and in valve replacement, while
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maintaining required overpressure protection for the steam e:r. rators and main steam system consistent with the requirements of ASME Boiler and Pressure i
Vessel Code,Section III, 1971 Edition.
Environmental Impacts of the proposed Action The Davis-Besse MSSVs provide steam generator and main steam system overpressure protection following turbine trip from rated power coincident with a total loss of condenser heat sink. This overpressure protection is accon.plished by assuring that the total relieving capacity of the MSSVs is at 4
least as large as the steam produced during operation at rated thermal power, and that the valve lift settings are in accordance with the ASME Code. With the proper relieving capacity of the valves, the pressure will hot exceed 110 percent of the design pressure for any system upset conditions. The proposed amendment would only incorporate the requirements of ASME Boiler and 3
Pressure Yessel Code, Section 111, 1971 Edition into the ACTION statement for l
LimitingConditionforOperation(LCf)3.7.1.1inplaceofTechnical Specification Table 4.7.-l.
The reduced High Flux Trip Setpoint, by using Equation 3.7-1, eliminates the unnecessary conservatisms while maintaining the required level of main steam system overpressure protection and does not impact any analyzed events in Chapter 15 of USAR. The integrated steam mass released through the MSSVs to the atmosphere is independent of this change and, therefore, previously postulated off-site doses due to the mass release are unaffected by these changes.
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lhe Commission has evaluated the environmen;al impact of the proposed amendment and has determined that post-accident radiological releases would not be greater than previously determined and occupational radiation exposure is unaffected. Neither does the proposed amendment otherwise affect radiological plant effluents during normal operation. Therefore, the Commission concludes that there are no significant radiological environmental impacts associated with this proposed amendment.
With regard to potential nonradiological impacts, the proposed amendment involves changes to the Main Steam Safety Valve setpoints and the reduced High Flux Trip setpoint.
It does not affect norradiological plant effluents and has no other environmental impact. Therefore, the Commission concludes that there are no significant nonradiological environmental impacts associated with the proposed amendment.
The Notice of Consideration of Issuance of Amendment and Opportunity for Hearing in connection with this action was published in the Federal Register onMay24,1988(53FR18631).
No request for hearing or petition for leave to intervene was filed following this notice.
Alternatives to the Proposed Action Since the Commission has concluded that the environmental effects of the proposed action are not significant, any alternative with equal or greater environmental impacts need not be evaluated.
The principal alternative would be to deny the requested amendment.
This would not reduce the environmental impacts attributable to this facility and would result in the MSSV setpoints remaining as they are specifically cited presently in the Technical Specifications.
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O* l Alternative Use of Resouregs, This action does not involve the use of resources not previously considered in the Final Environmental Statement related to operation of the I
Davis-Besse facility.
JgenciesandPersonsConsulted The Comission's staff reviewed the licensee's request and did not t
consult other agencies or persons.
FINDING OF NO SIGNIFICANT IMPACT The Comission has determined not to prepare an environmental impact statement for the proposed amendment.
Based upon the foregoing environmental assessment, we con",lude that the proposed action will not have a sign?ficant effect on the quality of the human environment.
For further details with respect to this action, see the application for
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amendment dated March 4, 1988 and supplemental letters dated May 4 and December 6,1988 which are available for public inspection at the Commission's Public Document Room, 2120 L Street, N.W., Washington D.C., and at the University of Toledo Library, Documents Department, 2801 Bancroft Avenue, j
Toledo, Ohio 43606.
Dated at Rockville, Maryland, this 5th day of September 1990.
FOR THE NUCLEAR REGULATORY COMMISSION A
John N. Hannon, Director Project Directorate 111-3 Division of Reactor Projects - III, IV, Y and Special Projects Office of Nuclear Reactor Regulation
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