ML20093J825
| ML20093J825 | |
| Person / Time | |
|---|---|
| Site: | LaSalle  |
| Issue date: | 09/21/1984 |
| From: | Office of Nuclear Reactor Regulation |
| To: | |
| Shared Package | |
| ML20093J821 | List: |
| References | |
| NUDOCS 8410170035 | |
| Download: ML20093J825 (3) | |
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SAFETY EVALUATION i
AMENDMENT NO. 4 TO NPF-18 LA SALLE COUNTY STATION, UNIT 2 DOCKET NO. 50-374 Introduction License Condition 2.C.(7) of License NPF-18 required installation of instrumentation that would automatically, shut down the reactor (in startup and refueling modes only) in the event of low control rod drive pump dis-charge pressure. This condition was to have been satisfied prior to completion of the startup test program.
By letter dated May 24, 1984, Comonwealth Edison Company (licensee) requested a license amendment which was issued as Amendment No. 3 effective July 24, 1984, and was intended to show compliance with License Condition 2.C.(7) and provide the necessary Technical Specifications to assure proper operation of the new scram capability.
By letter dated July 31, 1984, as supplemented by letters dated August 1 & 2, 1984, the licensee requested an exigent amendment to vacate Amendment No. 3 to the license, citing the fact that, on July 30, 1984 while testing the modification, spurious scrams occurred, indicating that with the existing trip setpoints, the modification cannot yet be declared fully operable, pending identification and correction of the cause of these scrams. Accordingly, the licensee has requested that the changes to the license and the Technical Specification authorized by Amendment No. 3 to NPF-18 be delayed until completion of the startup test program, as was originally provided for in License Condition 2.C.(7).
Evaluation Prior to issuance of License Amendment No. 3, License condition 2.C.(7) allowed completion of the startup test program before installation of this additional scram capability was required. The startup test program is expected i
to be completed in October 1984 at which time the instrumentation must be installed. Therefore, vacating License Amendmant No. 3, which reflected installation of the instrumentation, does not constitute a significant hazards consideration.
Since this plant modification has caused spurious reactor-trips, we agree that it is prudent not to require the instrumentation to be operable until this problem is resolved and appropriate corrective action is taken.
In the interim, to avoid spurious scrams while resolving the problem, the licensee intends to simply jumper out the low pressure scram logic, thus isolating this installed modification from the plant's reactor protection system. Therefore, the system and Technical Specifications will be the same as it was prescribed in the original license. We find this acceptable.
The NRC will inspect these o
i jumpers to assure that they have been properly installed.
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Also, since appropriate corrective action to resolve the spurious scrams may involve numeric changes in the instrument set points, we concur that tha prudent course of action is to vacate Amendment No. 3 and thus reinstate License Condition 2.C.(7).
No Significant Hazards Detemination Tha basis for thi previous detemination of no significant hazards concerning the proposed amendment remains unchanged.
The plant will be the same as it was prior to issuana of Amendment No. 3.
Amendment No. 3 was intended to both satisfy the License Condition 2.C.(7) and provide the necessary Technical Specifications to assure proper operation of a scram capability required which the licensee discovered to be premature. License Condition 2.C.(7) granted until the completion of the startup test program for completion of this additional scram capability. The~startup test program is expected to be completed in October 1984 at which time the licensee must demonstrate operability of the instrumentation.
The NRC staff concludes the proposed amendment will i,
not:
(1)
Involve a significant increase in the probability or i
consequence of an accident previously evaluated because the plant is as originally licensed, and the amendment only provides additional time for operability of scram instrumentation required by license condition.
(2) Create the possibility of a new or different kind of accident from any previously evaluated because the accident analysis is unchanged by a delay in operability of the instrumentation to completion of startup testing.
(3)
Involve a significant reduction in the margin of safety since the plant remain the same as originally licensed.
The staff has determined that a timely application for the proposed change was made and that exigent circumstances do exist and were not any fault of 1
j the licensee. The exigent circumstances result from the fact that the time is needed to confim the cause of the problem and to establish an adequate basis for the proper scram setpoint.
By requesting an exigent review, the licensee is avoiding a possible emergency amendment request in the event the facility were to incur a shutdown in the immediate future, and this new scram capibility would allow the Unit to restart due to additional spurious scrams.
Environmental Consideration This amendment which va ates Amendment No. 3 to NPF-18 and reinstates License
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Condition 2.C.(7) involves a change in the tir,e of installation or use of a facility component located within the restricted area as defined in 10 CFR Part 20. The staff has determined that the amendment involves 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 C
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Issuance of Amendment No. 4 to Facility Operating License No. NPF-18 La Salle County Station, Unit 2 DISTRIBUTION
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Local PDR PRC System NSIC LB#2 Reading PShuttleworth A80urnia TNovak JSaltzman, SAB CWoodhead, OELD OMiles HDenton JRutberg AToalston WMiller, LFM8 NGrace CJordan LHarman DBrinkman, SSPP T8arnhart(4)
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