ML20069Q355
| ML20069Q355 | |
| Person / Time | |
|---|---|
| Site: | Hope Creek  |
| Issue date: | 01/02/1991 |
| From: | Office of Nuclear Reactor Regulation |
| To: | |
| Shared Package | |
| ML20069Q353 | List: |
| References | |
| NUDOCS 9101150308 | |
| Download: ML20069Q355 (3) | |
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SAFETY EVALUATION BY THE OFFICE OF NUCLEAR REACTOR REGULATION-SUPPORTING AMEN 0 MENT NO.39 TO FACILITY OPERATING LICENSE NO. NPF.57 PUBLIC SERVICE ELECTRIC & GAS COMPANY ATLAKTIC CITY ELECTRIC COMPANY HOPE CREEK GENERATING STATION DOCKET NO. 50-354
1.0 INTRODUCTION
By letter dated September 4,1990, Public Service Electric & Gas Company requested an amendment to Facility Operating License No. NPF-57 for the Hope Creek Generating Station. The pro the Average-Power Range Monitor (APRM) posed amendment would eliminate downscals RPS scram Technical Specification (TS) requirements. The APRM downscale scram was' designed to reactivate the Intermediate Range Monitor (IRM) upscale scram functions when the associated APRM channel is downscale and the Reactor Mode switch is in the Run position. The surveillance tests for the APRM downscale trip function, required by the TS, require the plant to be placed in a " half scram" condition, thus increasing the probability of a spurious trip or ESF actuation, t
2.0 EVALUATION 1
The IRM upscale scram functions (IRM "high high" and inoperable trips) are automatically bypassed when the Reactor Mode switch is placed in the Run position. The APRM downscale scram was designed to reactivate the IRM u) scale scram functions when the associated APRM channel is downscale and tie Reactor Mode switch is in the'Run position. The licensee states that the only plant conditions under which' this could occur are:
1.
If the Reactor Mode switch is placed in the Run position before reactor power has increased to the indicating range of the APRMs during a plant startup, or l
2.
If the Reactor Mode switch remains in the Run position after reactor power has decreased below the indicating range-of the APRMs during a plant shutdown.
Under these conditions, both of which are induced by operator error, the accidents of concern with respect to the APRM downscale scram are the Rod Drop.
Accident (RDA) and the low power Rod Withdrawal Error (RWE).
Normally, proper Reactor Mode switch positioning is administrative 1y M ured by compliance with the integrated operating procedures for plant startup and shutdown. Considering the amount of attention norina11y'given by operators to the neutron monitoring system and integrated operating procedures during tartu nd shutdown ImpropSr$y positioned.it is unlikely that the Reactor Mode switch would be 9101150308 910102 PDR ADOCK 0S000354 P
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If the Reactor Mode switch is improperly positioned during a startup or shutdown, it is unlikely that a RDA or RWE'would, occur prior to completion of corrective action due to the " Infrequent" frequency classificatien of both of these accidents.
If the Reactor Mode switch is improperly positioned, as a result.of procedural non-compliance, and a RDA or RWE occurs prior to completion of corrective 4
action, plant protection is ensured by automatic system response, completely independent of the APRM downscale scram, as follows:
1.-
If a RDA occurs while the Reactor Mode switch'is in Run and the APRMs are downscale, reactor power will increase due to positive reactivity addition. The transient will be terminated w1en the RPS initiates an APRM neutron-flux upscale-scram.
2.
With the Reactor _ Mode switch in Run and the APRMs downscale, further control rod withdrawal is prohibited by the APRM Downscale Rod Block, thereby preventing a RWE.:
In summary, procedural compliance normally ensures proper Reactor Mode switch positioning.
If improper Reactor Mode switch' positioning. occurs, the probability of an accident or transient occurring: prior to completion of corrective action is low.
If.an accident or transient does occur prior to completion of corrective action, the licensee is-taking credit for the APRM 120% setpoint (upscale)_ scram and the APRM downscale tr_ip in the Control Rod Block actuation circuitry. Since both the APRM upscale scram and the control rod block actuation circuitries are required by the pl TS operability and surveillance testing, there Lis reasonable assuranceant that these-circuitries will perform their protection function when it is needed. We have reviewed the licensee's analysis _..and agree with their evaluation.
It is therefore concluded that the requested change would-not result in a significantly degraded APRM-safety' function.
Lastly, it is noted that the requested change results in a reduction _in the potential for spurious plant trips and ESF actuations;'this reduction has a positive impact on safety.
The staff was informed that the proposed changes will involve.a modification in the reactor protection system circuitry. The APRM downscale trip-circuits will be bypassed to eliminate this signal.
The staff will require the licensee to formally document-this. modification on the Docket, and-fully test the RPS.af ter the modification is implemented. Al' the'RPS test procedures should be updated to reflect this modification.
3.0- ENVIRONMENTAL CONSIDERATION This amendment involves a change to a requirement with respect to.the L
installation or use of a facility component located within the restricted j
area as defined in 10 CFR Part 20 and changes-to the surveillance i
requirements. The staff has determined that the amendment involves no l
significant increase inithe amounts, and no significant change in the-i
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types, of any effluents that may be released offsite and that there is no l
significant increase in individual or cumulative occupational radiation-exposure. The Comission has previously-issued a proposed finding that this amendment involves no significant hazards consideration and there has been no public coment on such finding. Accordingly, this amendment meets the elig)ibility criteria for categorical exclusion set forth in 10 1
CFR 51.22(c)(9.
Pursuantto10CFR51.22(b),:noenvironmentalimpact statement or environmental assessment need be prepared in connection with the issuance of this' amendment.
4.0 _ CONCLUSION,
.The Comission made a proposed determination that-the amendment involves no significant hazards consideration which was published in the Federal-Regjster (55 FR 40473)'on October 3, 1990 and consulted with the State of New Jersey.
No public coments were received and the State of New Jersey.
did not have any comments.
The staff 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, and (2) such activities will be conducted-in compliance with the Comission's regulations and the issuance of this amendment will not be inimical to the comon defense and security nor to the health and safety of the public.
Dated: January 2, 1991 Principal Contributor: S. Dembek