ML20082L689
| ML20082L689 | |
| Person / Time | |
|---|---|
| Site: | Peach Bottom  |
| Issue date: | 04/18/1995 |
| From: | Office of Nuclear Reactor Regulation |
| To: | |
| Shared Package | |
| ML20082L678 | List: |
| References | |
| NUDOCS 9504210255 | |
| Download: ML20082L689 (3) | |
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'I 3&EUY EVALUATION BY THE OFFICE OF NUCLEAR REACTOR REGULATION RELATED TO AMENDMENT NOS. 200 AND 202 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-M.KET NOS. 50-277 AND 50-278 l
1.0 INTRODUCTION
By letter dated October 25, 1994, as supplemented by letter dated February 13, 1995, the PECO Energy Company (the licensee) submitted a request for changes to the Peach Bottom Atomic Power Station, Unit Nos. 2 and 3, (Peach Bottom, PBAPS) Technical Specifications (TS). The requested changes would clarify the Technical Specification surveillance requirements and bases for the high pressure coolant injection (HPCI) system testing at low reactor pressure. The February 13, 1995, letter provided clarifying information that did not change i
the initial proposed no significant hazards consideration determination.
2.0 EVALUATION The high pressure coolant injection system is one of the core standby cooling systems installed at Peach Bottom whose objective, in conjunction with primary and secondary containment features, is to limit the release of radioactive j
material to the environment following a loss of coolant accident (LOCA). The
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HPCI system is provided to ensure that the reactor is adequately cooled to limit fuel-clad temperature in the event of a small break in the nuclear pressure boundary and subsequent loss of coolant which does not cause the rapid depressurization of the reactor vessel. The HPCI system consists of a steam turbine driven pump, piping, valves and controls necessary to meet the above objective.
l In order to assure the ability of the system to meet its design objectives, j
surveillance requirements are included for the HPCI system in the TS. One of t
the existing requirements, TS 4.5.C.I.e, currently states "HPCI Subsystem testing shall be performed as follows:... (e) Flow Rate at 150 psig Steam Pressure." The test frequency is currently specified as once-per-operating cycle. A separate surveillance requirement, 4.5.C.I.d specifies that the i
HPCI subsystem flow rate be tested at 1000 psig steam pressure once per three months. HPCI flow rate tests are specified at these two separate pressures in order to verify the system's capability to provide rated flow over its j
9504210255 950418 PDR ADOCK 05000277 P
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, operating range.
During NRC inspection 50-277/90-200 and 50-278/90-200, the NRC staff identified that the licensee had previously performed the surveillance test associated with SR 4.5.C.I.e at pressures greater than 150 psig (160 psig) although no allowance for a range of test pressua: was allowed by the existing TS (Unratolved Item (URI) 90-200-12).
P e licensee stated in response to URI 90-200-12 that PBAPS TS would be converted to the improved Standard TS (iSTS) which would provide a range of acceptable test pressures.
By letter dated September 29, 1994, the licensee applied to convert the Peach Bottom TS to an improved STS version based on NUREG-1433, " Standard Technical Specifications, General Electric Plants, BWR/4," dated September 1992.
The license amendment request evaluated in this SE clarifies the requirements of TS 4.5.C.I.e in advance of staff review of the improved TS conversion application.
In order to test the HPCI system at low pressure, a stable steam supply pressure must be established and maintained. At Peach Bottom, operating experience has shown that steam pressures as high as 175 psig are needed before the electro-hydraulic catrol system can provide stable steam pressure regulation.
PEC0 has proposed b revise TS 4.5.C.1.e to reflect the words of NUREG-1433. The revised wording states that for the HPCI Subsystem, on a once-per cycle frequency, " verify, with reactor pressure s 175 psig the HPCI pump can develop a flow rate 2 5000 gpm against a system head corresponding to reactor pressure." The licensee has also proposed a footnote to 4.5.C.I.e i
which states that "Not required to be performed until 12 hours1.388889e-4 days <br />0.00333 hours <br />1.984127e-5 weeks <br />4.566e-6 months <br /> after reactor steam pressure and flow are adequate to perform the test." The licensee has also proposed to revise the associated TS bases to reflect the need to have stable reactor pressure for performing the HPCI low pressure test.
The licensing analysis of record with regard to emergency core cooling system performance is NEDC-32163P, " Peach Bottom Atomic Power Station, Units 2 and 3 SAFER /GESTR-LOCA Loss of Coolant Accident Analysis" dated January 1993 (SAFER /GESTR). The SAFER GESTR report states that the minimum assumed operating pressure for the HPCI system is 150 psid (vessel to drywell). The proposed revision to the SR would allow the HPCI system not to be periodically tested down to the assumed minimum value. The licensee states that the effect on analytical results of raising the assumed minimum HPCI operating pressure to 175 psig, in the SAFER /GESTR analysis is insignificant. The staff accepts the licensee's assertion by recognizing that the low pressure coolant injection system and the low pressure core spray system are assumed in SAFER /GESTR to inject up to a maximum of 295 psid and 289 psid respectively.
These maximum injection pressures provide sufficient overlap with the assumed range of injection pressures for the HPCI system.
In addition, the automatic depressurization system (ADS) is capable of depressurizing the reactor vessel down to the range of low p:-essure system operation.
The staff has reviewed the licensee's proposed changes.
The proposed SR
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wording implements the wording of SUREG-1433 and clarifies existing requirements.
The impact of raising HPCI surveillance test pressure on overall emergency core cooling system performance is minimal for the reasons articulated in the preceding paragraph.
For these rr,asons, the staff finds the licensee's 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 ENVIRONMENTAL 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 the 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 consideration, and there has been no public comment on such finding (59 FR 55498). 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, j
and (3) the issuance of the amendments will not be inimical to the common 1
defense and security or to the health and safety of the public.
Principal Contributor:
J. Shea Date:
April 18, 1995
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