ML20134A605

Safety Evaluation Re Util 831107 & 850910 Responses to Generic Ltr 83-28,Item 1.1, Post-Trip Review Program Description & Procedures. Program & Procedures Acceptable

ML20134A605
Person / Time
Site:	Point Beach
Issue date:	10/22/1985
From:	Office of Nuclear Reactor Regulation
To:
Shared Package
ML20134A597	List: ML20134A595 ML20134A605
References
GL-83-28, NUDOCS 8511070423
Download: ML20134A605 (5)

Text

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, UNITED STATES 8  % NUCLEAR REGULATORY COMMISSION 7, t WASHINGTON, D. C. 20555

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SAFETY EVALUATION BY THE OFFICE OF NUCLEAR REACTOR REGULATION WI5 CON 5IN ELECTRIC POWER COMPANY POINT BEACH NUCLEAR PLANT, UNIT 5 1 AND 2 GENERIC LtIIER 83-28, ITEM 1.1 - POST -TRIP REVIEW .

(PROGRAM DESCRIPTION AND PROCEDURE)

DOCKET N05. 50-266 AND 50-301 I. INTRODUCTION On February 25, 1983, both of the scra:n circuit breakers at Unit 1 of the Salem Nuclear Power Plant (SNPP) failed to open upon an automatic reactor trip signal from the reactor protection system. This incident occurred during plant start-up and the reactor was tripped manually by the operator about 30 seconds after the initiation of the automatic trip signal. Failure of the circuit bteakers has been determined to be related to the sticking of the under voltage trip attachment. On February 22, 1983, an automatic trip occurred during the start-up of SNPP, Unit 1, as the result of steam generator low-low level. In this case, the reactor was tripped manually by the operator almost coincidentally with the automatic trip. On February 28, 1983, the NRC Executive Director for Operations directed the staff to investigate and report on the generic implications of these occurrences. The results of this staff investigation are reported in NUREG-1000, " Generic Implications of ATWS Events at the Salem Nuclear Power

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.' ant." As a result of this investigation, the Commission requested (by Generic Letter 83-28 dated July 8,1983) all licensees of operating reactors, applicants for an operating license, and holders of construction permits to respond to certain generic concerns. These concerns are categorized into the following four areas: (1) Post-Trip Review, (2)

Equipment Classificatior ed Vendor Interface, (3) Post-Maintenance Testing,

. and (4) Reactor Trip syst m Reliability Improvements.

The first action item, rost-Trip Review, consists of Action

• Item 1.1,

" Program Description and Procedure" and Action Item 1.2, " Data and Infonnation Capability." This evaluation addresses Action item 1.1 only.

8511070423 85 PDR ADOCK PDR P

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, Wisconsin Electric Power Company, licensee for Point Beach Nuclear Plant.

Units 1 and 2 responded to Generic Letter 83-28 on November 7,1983. The I staff reviewed the licensee's response and transmitted its initial evalua-tion on July 29, 1985 and also requested additional infonnation relating to Action Item 1.1. The licensee provided the additional information by letter dated September 10, 1985.

II. REVIEW GUIDELINES -

The following review guidelines were developed after initial evaluation of several utility responses to Item 1.1 of Generic Letter 83-28 and incorporate the best features of these submittals. Therefore, these review guidelines effectiv'ely represent a ' good practices" approach to post-trip review. We have reviewed the licensee's response to Item 1.1 against these guidelines:

A. The licensee or applicant should have systematic safety assessment procedures established that will ensure that the following restart criteria are met before restart is authorized.

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The post-trip review team has determined the root cause and sequence of events resulting in the plant trip.

l Near tern corrective actions have been taken to remedy the cause

• I of the trip.

The post-trip review team has performed an analysis and determined x that the major safety systems responded to the event within

' ~

, spectfled 'lisits of the prima 7y"syitiun ~p&asieters.

i The post-trip review has not resulted in the discovery of a potential safety concern (e.g., the root cause of the event occurs with a frequency significantly larger than expected). ;

If any of the above restart criteria are not met, then an independent assessment of the event is performed by the Plant

! Operations Review Cannittee (PORC), or another designated group with similar authority and experience.

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.__ ._ .___i_____..__-._.____ __ __ ._. _ _ _. _ . _

t B. Theresponsibilitiesandauthoritiesofthepersonnelwho[willperform ,

the review and analysis should be well defined. l The post-trip review team leader should be a member of plant management at the shift supervisor level or above and should hold or should have held an SRO license on the plant. The team leader should be charged with overall responsibility for directing the post-trip review, including data gathering and data assessment and he/she should have the necessary authority to obtain all personnel and data needed for the post-trip review.

A second person on the review team should be an STA or should hold

! a relevant engineering degree with special transient analysis training.

I The team leader and the STA (Engineer) should be responsible to concur on a decision / recommendation to restart the plant. A nonconcurrence from either of these persons should be sufficient to l p.revent restart until the trip has been reviewed by the PORC or equivalent organization.

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j C. The licensee or applicant should indicate that the plant response to the j trip event will be evaluated and a determination made as to whether the i

plant response was within acceptable limits. .The evaluation should

include

4 A verification of the proper operation of plant systems and equipment by comparison of the pertinent data obtained during the post-trip review to the applicable data provided in the FSAR.

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An analysis of the sequence of events to verify the proper functioning of safety related and other important eipipment. Where possible, comparisons with previous similar events should be made.

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4 D. The licensee or applicant should have procedures to ensure tha't all i

physical evidence necessary for an independent assessment .is preserved.

E.

Each licensee or applicant should provide in its submittal, copies of l the plant procedures which contain the information required in Items A '

through D. As a minimum, these should include the following:

The criteria for determining the acceptability of restart -

The qualifications, responsibilities and authorities of key personnel involved in the post-trip review process The methods and criteria for detemining whether the plant -

l variables and system responses were within the limits as described in the FSAR The criteria for determining the need for an independent reviev.

III. EVALUATION

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. By letters dated November 8, 1983, and September 10, 1985, the licensee of

, Point Beach Nuclear Plant Units 1 and 2, provided information regarding its Post-Trip Review Program and Procedures. We have evaluated the licensee's program and procedures against the review guidelines developed as described in Section II. A brief description of the licensee's response and the staff's evaluation of the response against each of the review guidelines is provided below:

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A. The licensee has established the criteria for determining the acceptability of restart. Based on our review, we find that the licensee's criteria conform with the guidelines as described in ,

Section II.A and, therefore, are acceptable.

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B.

The qualifications, responsibilities and authorities of thh personnel

~ who will perform the review and analysis have been clearly described.

We have reviewed-the licensee's chain of command for respon'sibility for

. post-trip review and evaluation and find it acceptable.

't C.

i The licensee has des'cribed the methods and criteria for comparing' the event information with known or expected plant behavior. Based on our

' review, we find them to be acceptable.

D.

With regard to the criteria for determining the need for independent assessment of an event, the licensee has indicated that if any of the restart criteria are not met, an independent assessment of the event will be performed.

In addition, the licensee has established procedures to ensure that all physical evidence necessary for an independent assessment is preserved. We find that these actions to be taken by the licensee conform to the guidelines as described in Sections II.A. and D. -

E.

The licensee has provided for our review a systematic safety assessment program to assess unscheduled reactor trips. Based on our review, we find that this program is acceptable.

7 V., CONCLUSION

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i l Based on our review, we conclude that the licensee's Post-Trip Review P and Procedures for Point Beach, Units 1 and 2, are acceptable. l Principle Contributors:

D. Shum T. Colburn 0

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