ML17278A266
| ML17278A266 | |
| Person / Time | |
|---|---|
| Site: | Columbia  |
| Issue date: | 06/25/1985 |
| From: | Office of Nuclear Reactor Regulation |
| To: | |
| Shared Package | |
| ML17278A265 | List: |
| References | |
| TAC-56945, NUDOCS 8507100426 | |
| Download: ML17278A266 (5) | |
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UNITEDSTATES NUCLEAR REGULATORY COMMISSION WASHINGTON, D. C. 20555 SAFETY EVALUATION AI1EHDIIENT NO.
13 TO NPF-21 WPPSS NUCLEAR PROJECT NO.
2 DOCKET NO. 50-397 INTRODUCTION By letter dated February 27, 1985 (G02-85-098), llashington Public Power Supply System (the licensee) requested an amendment to the Technical Specifications of Facility Operating License NO. NPF-21 for IIuclear Plant No. 2.
Additional, information and clarifications were provided by the licensee during a teleconference on March 26, 1985.
EVALUATION The Technical Specifications as presently written (Tables 3,3.3-1, 3.3.3-2 and 4.3.3.1-1) contain the requirements to perform a monthly Channel Functional Test and an annual (during refueling outage)
Channel Calibration on the Pump Discharge Pressure-High (pump running) instrumentation.
The present HPCS design incorporates minimum flow valve logic based on concurrent conditions of high pump discharge pressure and low system flow.
The pressure switch which provides the high discharge pressure (pump running) input takes its signal downstream of the pump discharge check valve.
Consequently, upon securing the pump following closure of the test flow path, high pressure can be trapped downstream of the check valve arid result in the minimum flow valve remaining open with the pump off.
This necessitates depressurizing the system to close the valve.
The amendment seeks to replace the high discharge pressure signal with a pump running input taken from the pump breaker.
Thus, the valve would open on low flow and breaker closed (pump running) and would close on high flow or with the breaker open.
With this design enhancement, the pump discharge pressure-high signal would no longer be used or needed.
The amendment eliminates drift and calibration errors associated with instrumentation and their attendant failure modes.
Actuation of the system itself is being made even more affirmative from the standpoint of signal reliability; that is, the proposed pump logic is a positive indication of the pump breaker position and will automatically reflect the status of the HPCS pump without any of the problems associated with instrument channels.
Furthermore, the pump minimum flow logic will be functionally verified during the HPCS Pump quarterly Operability Test as well as during the 18 month Logic System Functional Test.
8507100426 850625 PDR ADOCN 05000397 P
Me understand from the licensee that the original LPCS minimum flow valve logic is the same as now proposed for HPCS.
According to the licensee only the pump discharge pressure switch is deleted.
The pump discharge pressure indications are not changed or deleted.
The deletion of the pump discharge pressure switch will not result in any decreased
- safety, hence the proposed amendment to Technical Specification Tables 3.3.3-1, 3.3.3-2 and 4.3.3.1-1 is acceptable to the staff.
FINAL NO SIGNIFICANT HAZARDS CONSIDERATION DETERMINATION The Commission has provided standards for determining w ether a significant hazards consideratior exists (10 CFR 50.92(c)).
A proposed amendment to operating license for a facility involves no significant hazards consideration if operation of the facility in accordance with the proposed amendment would not (1) involve a significant increase in the probability or consequences of an accident.
previously evaluated; (2) create the possibility of a new or differen7. kind of accident from an accident previously evaluated; or (3) involve a sicr ifi-cant reduction in a margin of safety.
The licensee has determined and thE'RC staff agrees that the requested amendment per 10 CFR 50.92 does not:
1}
Involve a significant increase in xhe probability or consequences of an accident previously evaluated because replacing an instrument signal with a non-instrumented signal does not degrade the HPCS system's ability to perform following an accident nor does it degrade the system pressure boundary; or 2)
Create the possibility of a new or different kind of accident than-previously evaluated because the post accident ECCS function of the system will not be affected; or 3)
Involve a significant reduction in a margin of safety because the proposed change will have no effect on the ability of the HPCS system to meet its associated ECCS injection functions.
Accordingly, the Commission has determined that this amendment involves no significant hazard consideration.
On June 18, 1985, the Commission published in local newspapers, notice of its proposal to amend the Supply System's license.
No public comment was received relative to this amendment.
In addition the State.of Washington had been notified by the Supply System of the request for amendment and they indicated concurrence by telephone on June 17, 1985.
ENVIRONtiENTAL CONS IDERATION This amendment involves a change to the requirement with respect to installation or use of a facility component located within the restricted area as defined i>> 10 CFR Part 20.
The staff has determined that the amendment involves no significant change in the types or significant increase in the amounts of any e.fluents that may be released offsite, and that there is no significant increase in individual or cumulative occupational radiation
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exposure.
The Commission has deterDined that this amendment involves no significant hazards consideration.
Accordingly, this amendment meets the eligibility criteria for categorical exclusion set forth in 10 CFR Section 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 this amendment.
COHCLUS ION lie have 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; and (2) such activi-ties will be conducted in compliance with the Commission's regulations and
~ the issuance of this amendment will not be inimical to the common defense and security or to the health and safety of the public.
O,ted. Jim 8 5 m Principal Contributor:
G.
Thomas
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