ML13326A662

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Safety Evaluation Supporting Amend 58 to License DPR-13
ML13326A662
Person / Time
Site: San Onofre Southern California Edison icon.png
Issue date: 11/06/1981
From:
Office of Nuclear Reactor Regulation
To:
Shared Package
ML13326A660 List:
References
TASK-***, TASK-TM TAC-44128, NUDOCS 8111300185
Download: ML13326A662 (5)


Text

Eq,0 UNITED STATES NUCLEAR REGULATORY COMMISSION WASHINGTON, D. C. 20555 SAFETY EVALUATION BY THE OFFICE OF NUCLEAR REACTOR REGULATION SUPPORTING AMENDMENT NO.

58 TO LICENSE NO.

DPR-13 SOUTHERN.CALIFORNIA EDISON COMPANY SAN DIEGO GAS & ELECTRIC COMPANY SAN ONOFRE UNIT NO. 1 DOCKET NO. 50-206

1.0 INTRODUCTION AND BACKGROUND

1.1 Introduction By letter dated May 7, 1981, Southern California Edison Company.and San Diego Gas and Electric Company (the licensees) proposed changes to the San Onofre Nuclear Generating Station (SONGS) Unit No. 1, Technical Specifications and addition of Licensing Conditions.

This proposal superseeds a similar request proposed in a letter dated February 8, 1980. The staff has not completed its review of all the proposed changes submitted by this application but this Safety Evaluation documents the results of the reviews that have been com pleted. The amendment incorporates certain Three Mile Island (TMI)-2 Lessons Learned Category "A" requirements.

The licensee's request is in.

direct response to the NRC staff's letter dated July 2, 1980.

1.2 Background

By our letter dated September 13, 1979, we issued to all operating nuclear power plants requirements established as a result of our review 6f.the TMI-2 accident. Certain of these requirements, designated Lessons Learned Category "A" requirements, were to have been completed by the licensee prior to any operation subsequent to January 1, 1980.. Our evaluation of the licensee's compliance with these Category "A" items was attached to our letter-to SCECO dated May 2, 1980.

SONGS 1 was in.an extended maintenance outage from March, 1980 through May of 1981 and their submittal,reflects some of the modifications completed during this.period.

In order to provide reasonable assurance that operating reactor facilities are maintained within the limits determined acceptable following the implementation of the TMI-2 Lessons Learned Category "A" items, we requested that licensees amend their TS to incorporate additional Limiting Conditions for Operation and Surveillance Requirements, as appropriate. This request was transmitted to all 8111300185 811106 PDR ADOCK 05000206 PDR

licensees on<July 2, 1980.

Included therein were model specifications that we had determined to be acceptable.

Each of the issues identified by the NRC staff and the licaisee's response is discussed in the evaluation-below; except auxiliary feedwater automatic-initiation, which -will be resolved in a-separate-issuance.

2.0 EVALUATION 2.1.1 Emergency Power Supply Requirements The press'urizer water.level indicators, pressurizer relief and block valves, and pressurizer heaters are important in a post-accident situation. Adequate emergency power supplies add assurance of post accident functioning of these components. The facility's design has the requisite emergency power supplies. We find the TSs provide appropriate surveillance and actions in the event of component inoperability and are thus acceptable.

2.1.3.a Direct Valve Indication..

The licensee has installed stem mounted limit switches with CONAX con ductor seal module assemblies at each switch connector on the PORVs, their associated block valves and the safety valves.

Each limit switch has a position indicator in the control room. Alarms are provided-in

-the control room to indicate 'i'f either of the.PORVs or safety valves are open. The stem mounted limit switches are. powered from vital buses.

The licensee has submitted TSs that provide for 31-day channel check and 18-month.channel calibration requirements.

'These TSs are acceptable as they meet our July 2, 1980 model TS criteria.

2.1 3.b Instrumentation for-Inadequate Core Cooling.

The licensee has installed an instrument system to detect the effects of inadequate core cooling. This instrument system, a subcooling meter, receives and pro.cesses date from existing plant instrumentation.

The licensee has agreed-to TS with a monthly'channel check and a refueling interval channel calibration requirement and appropriate actions to be taken in the event of component inoperability.. We conclude the TS are acceptable as they provide adequate surveillance and meet our July 2, 1980 model TS criteria.

2'.1.4 Containment Isolation The licensee's June 25, 1979 and January 17, 1980 submittals identified the essential and non-essential systems and the bases for the essential system' classification.

The isolation control system was modified to provide diverse containment isolation signals.

Non-essential systems are isolated automatically.upon receipt of a safety injection sigal or a containment high pressure signal.

-3 Containment siolation system relay panels have been installed to multiply the containment isolation actuation signal for individual vslve control-.--- Each-valve cht6trol circuit consists of a latching relay control and override control in addition to.the valve position indication circuit. The latching control scheme prevents automatic reopening of the isolation valve on containment isolation actuation signal reset.

The licensee has made the additional isolation control modifications described in their March 25, 1980 submittal.

These modifications preclude.group reopening of the isolation valves., so that reopening is accomplished on a valve-by-valve or penetration basis. The surveillance requirements for the containment purge supply and exhaust valves is currently under review by the licensee and NRC staff. The instrumentation requirements for these valves is under active review in SEP. The submitted TS's are therefore acceptable until the reviews are complete.

2.1.5 Dedicated Penetrations for External Recombiners or Post-Accident External Purge System The NRC's position is that dedicated containment isolation systems should be used for the external recombiners or purge systems that meet redundancy and single failure requirements.

The licensee would utilize a purge system for post-accident hydrogen.

control.

Those systems that could be used are described in the licensees March 25, 1980 submittal.. The submittal also includes a single failure analysis of the system for the hydrogen control function, and the containment integrity function.

2.1.6.a Integrity of Systems Outside Containment Our request indicated that licensees should be required to periodically conduct a System Integiryt Measurements Program to prevent the release of significant.amounts of radioactivity to the environment via leakage from engineered safety systems and auxiliary, systems which are located outside reactor containment. The licensee's program includes provisional for a preventive-maintenance program and periodic visual :inspections.

The program also includes system leak test measurements at frequencies not to exceed refueling cycle intervals.

Based on our review we find that inclusion of this requirement.as a license condition satisfies our-requirement and is acceptable.

-A

-4 2.l.7b Auxiliary Feed Flow Indication Control grade auxiliary feediflow indication has been provided for each steam generator. Diverse backup indication is provided by steai generator level indicators in the control room. The power to the.

auxiliary feedwater flow indication is from a vital bus.

The accuracy of the auxiliary feed flow is within the requirement of +10%.

The licensee has submitted TSs with a monthly channel check and a refueling outage. calibration-requirement; thus the TSs are acceptable and they meet out July 2, 1980 model TS criteria.

2.T.8.c Iodine Monitoring We requested that the-licensees implement a program which will ensure the capability to determine the airborne iodine concentration in areas requiring personnel access under accident conditions. The licensee's program includes.training of personnel, procedures for monitoring and provisions for maintenance of sampling and analysis equipment.

Based on our review we find that-inclusion of this requirement as a, license condition satisfies our requirement and is acceptable.

2.2.1.b Shift Technical Advisor Our request indicated that the TS related to minimum shift manning should be revised to-reflect the augmentation of Shift Technical Advisor. The licensee'.s application would add one Shift Technical Advisor to each shift to perform the function of accident assessment during reactor operation. The individual performing this function will have at least a bachelor's degree or equivalent in-a scientific or engineering discipline with special training in plant design, and response and analysis of the plant for-transients and accidents.

Part of the Shift Technical Advisor duties are related to operating experience review function. Based on our review, we find the licensee's submittal satisfies our requirement and is, therefore, acceptable.

3.0 ENVIRONMENTAL CONSIDERATION

We have determined that the amendment does not authorize a change in effluent types or total amounts not an increase in power level and will not result in any significant environmental impact. Having made this determination, we have further concluded that the amendment involves an action which is insignificant from the standpoint of environmental impact.

and, pursuant to 10 CFR §51.5(d)(4), that an environmental impact statement or negative declaration and environmental impact appraisal need not be prepared in connection with the issuance-of this amendment.

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4.0 CONCLUSION

We have concluded, based on the consideration discussed above, that:

(1) because the amendment doesnot involve. a significant7 ilthc'iase fin the pro bability or consequences of'accidents previously considered and does not involve a significant decrease in a safety margin, the amendment does not involve a significant hazards consideration, (2) there is reasonable assurance that the health and safety of the public will not be endangered by operation int he proposed manner, and (3) such activities 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.

Date:

November 6, 1981