ML20096C954
| ML20096C954 | |
| Person / Time | |
|---|---|
| Site: | Peach Bottom  |
| Issue date: | 01/11/1996 |
| From: | NRC (Affiliation Not Assigned) |
| To: | |
| Shared Package | |
| ML20096C951 | List: |
| References | |
| NUDOCS 9601180384 | |
| Download: ML20096C954 (3) | |
Text
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UNITED STATES j
NUCLEAR REGULATORY COMMISSION l
WASHINGTON, D.C. 20666 4 001
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SAFETY EVALUATION BY THE OFFICE OF NUCLEAR REACTOR REGULATION RELATED TO AMENDNENT NOS 211 AND 216 TO FACILITY OPERATING LICENSE NOS. DPR-44 and DPR-56 PECO ENERGY COMPANY PUBLIC SERVICE ELECTRIC AND GAS COMPANY DELMARVA POWER AND LIGHT COMPANY ATLANTIC CITY ELECTRIC COMPANY PEACH BOTTOM ATOMIC POWER STATION. UNIT NOS. 2 AND 3 DCCKET NOS. 50-277 AND 50-278
1.0 INTRODUCTION
By letter dated November 30, 1995, the PECO Energy Company (the licensee) submitted a request for changes to the Peach Bottom Atordic Power Station, Unit Nos. 2 and 3, Technical Specifications (TS). The requested changes would revise the minimum allowable control rod scram accumulator pressure and charging water header pressure from a value of 955 psig to a value of 940 psig.
2.0 EVALUATION Control rods are provided in a boiling water reactor as part of the reactivity controls systems.
The safety objective of the control rods is to rapidly shut down the reactor to prevent fuel damage from any abnormal operating tra'sient.
Positioning of the control rods within the reactor, including rapid insertion, is performed with control rod drive mechanisms and the associated control rod drive hydraulic system. A scram accumulator is provided as part of the.
hydraulic control unit for each control rod. The scram accumulator stores energy in the form of pressurized water to insert a control rod independent of any other form of energy.
Pressure in the accumulator is maintained with a supply of pressurized nitrogen.
Pressurized water is provided to the accumulators via the control rod drive hydraulic system charging header.
When reactor pressure is greater than 900 psig, the reactor pressure alone is sufficient to fully insert all control rods if required. However, when reactor pressure is less than 900 psig, reactor pressure alone may not be sufficient to fully insert all control rods.
Under these conditions, the pressure in the scram accumulators provides assurance that the rods will insert as required.
In order to ensure that accumulator pressure is 9601180394 960111 PDR ADOCK 05000277 P
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. adequately maintained at all times, technical specification requirements are imposed on minimum accumulator pressure and minimum charging header pressure.
During the licensee's development of its submittal for improved technical specifications (Technical Specification Change Request (TSCR) 93-16, submitted September 29,1994), the licensee proposed a value of 955 psig as the TS limit on scram accumulator and charging water header minimum pressure in TS 3.1.5.B.1, surveillance requirement (SR) 3.1.5.1, SR 3.9.5.2, SR 3.10.8.6 and in the associated TS Bases. The 955 psig value represented a nominal value for the accumulator and charging water header. The staff issued the improved technical specifications as Amendments 210 and 214 to the Peach Botton Atomic Power Station operating licenses on August 30, 1995.
The licensee subsequently reviewed General Electric (GE) Service Information Letter (SIL) 429 Revision 1.
GE SIL 429 Revision 1, recommends that licensees amend the TS to allow the accumulator pressure switch setpoint to 940 psig or greater. The accumulator pressure switch causes an alarm to activate in the control room if accumulator pressure drops below the setpoint. The licensee has proposed to change the TS requirement for scram accumulator minimum pressure and charging water header minimum pressure to 940 psig or greater to be consistent with the SIL recommendations, to take full advantage of the setpoint range and to provide more margin to the Technical Specification limits during normal operation. The licensee stated that the minimum pressure of the accumulator water required to provide sufficient stored energy to complete a reactor scram is 940 psig.
The staff has reviewed the licensee's application. The proposed' changes are consistent with the GE recommendations for the Peach Bottom boiling water reactor product line and are adequate to ensure that control rods fully insert into the core under required conditions. Therefore, the staff finds the proposed changes acceptable.
3.0 STATE CONSULTATION
In accordance with the Commission's regulations, the Pennsylvania State official was notified of the proposed issuance of the amendments. The State official had no comments.
4.0 ENVIRmflENTM. CONSIDERATION The amendments change a requirement with respect to installation or use of a facility component located within the restricted area as defined in 10 CFR Part 20 and change surveillance requirements. The NRC staff has determined that the amendments involve no significant increase in the amounts, and no significant change in the types, of any effluents that may be released offsite, and that there is no significant increase in individual or cumulative occupational radiation exposure. The Commission has previously issued a proposed finding that the amendments involve no significant hazards
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' consideration, and there has been no public comment on such finding (60 FR 63073). Accordingly, the amendments meet the eligibility criteria for categorical exclusion set forth in 10 CFR 51.22(c)(9).
Pursuant to 10 CFR 51.22(b) no environmental impact statement or environmental assessment need be prepared in connection with the issuance of the amendments.
5.0 CONCLUSION
The Commission has concluded, based on the considerations discussed above, that:
(1) there is reasonable assurance that the health and safety of the public will not be endangered by operation in the proposed manner, (2) such activities will be conducted in compliance with the Commission's regulations, and (3) the issuance of the amendments will not be inimical to the common defense and security or to the health and safety of the public.
Principal Contributor:
J. Shea Date:
January 11, 1996