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Critique of Integrated Plant Safety Assessment,Sep.
	ML18047A328
Person / Time
Site:	Palisades
Issue date:	04/27/1982
From:	Bush S; AFFILIATION NOT ASSIGNED
To:	;
Shared Package
ML18047A285	List: ML18047A284; ML18047A327; ML18047A328; ML18047A329; ML18047A330;
References
	NUDOCS 8205190066
	Download: ML18047A328 (6)
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PAL I SADES PLANT A CRITIQUE OF THE INTEGRATED PLANT SAFETY ASSESSMENT SYSTEMATIC EVALUATION PROGRAM S. H. Bush Since Palisades is the first plant reviewed under the Systematic Evalua-tion Program, the approach taken and the criteria us.ed to establish the accept-ability of assessment are somewhat tentative, particularly because there has been no opportunity to interface with authors and othi=r reviewers. Two sug-gested benchmQrks are:

~ Does the report meet the original AEC/NRC Corrrnission Charter. for SEPs.

Are the items identified as problems adequately described, including justification of their resolution.

An examination of documents SECY-76-545 and SECY-77-561 provided some insight into the approach used to handle SEP plants. The five program objec-tives can be used as criteria for measuring compliance. The suggested approach for handling deviations can permit an assessment of the resolution~ suggested in the Palisades report. These criteria follow.

The following five objectives of the program were established by the Task Force:

1.* The review program must assess the adequacy of the design and opera-tion of all currently licensed nuclear power plants.

2. The program should establish documentation which shows how each oper-ating plant compares,with current criteria.on significant safety iss *.s, and provide a rationale for acceptable departures from the~e criteria.

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0205190066 820430 PDR ADOCK 05000255 p PDR

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3. The program should provide for the capability to make integrated and balanced decisions ~ith respect to any required backfitting.

4. The program should be structured for early identification and resolu-tion of significant deficiencies.

_5. The program should efficiently utilize available resources and mini-mize* requirements for additional resources by NRC or industry.

The planned syst~matjc_evaluation would establish. t~~ a~equacy of all operating power ~eactors wit,h respect to safety and provide clear written documentation bases for this conclusion. - #

When deviations from c~rrent licensing criteria are identified, the fol-lowing alternatives (or combinations of alternatives) will be considered as a basis for establishing acceptability:

1. The deviation can be justified as not significantly decreasing the level of safety.

2. Use of non-safety systems to perform safety functions.

3. Administrative or procedural changes to enhance system reliability.

4. Augmented surveillance programs.

5. Selected backfitting to enhance system reliability.

Presumably one critical evaluation of Appendix A will be sufficient on the assumption that these items will remain unchanged in the future. While Appen-dix B covering generic issues may change somewhat, one review as to adequacy should be suffi~ient. Obviously~ Appendix C will change because of plant and site specificity. Appendices E and F will need review on a case-by-case basfs.

t Examination of Appendices A, B, and C unearthed some problems. The

~ording,-teferences and approach used with the items-in Appendix A reveal the 11 rnind set" of the 1976-77 _period.* Personally, I feel that some -of the strong positions taken then have weakened in the past 4-5 years. An example mjght be valve lockout *. As predicted some of the locked out valves have been found to be in the wrong position so the effects of an accident would be exaggerated *.

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,. e .9-I_ $USpect a probabilistic approach could lead to dropping others; however, the option appears to exist in the so-called 11 lesser safety significance 11 approac.h.

With regard to Appendix B as related to A, I am at a lo~s as to why some of the unresolved safety issues were ignored. Specifically, issues A-11, A-31,

A-45 and A-49 were not cited. If these were included, some other items would shift to the generic packet. While I understand the words regarding folding in* the USI and TMI issues, it is not immediately obvious how this will be

accomplished.

. *-I suspect that the issues- in Appendix A~ if .wri'tten in 1982-82, would* dif-fer substantially from the words generated in 1977; however, those words can be accepted_.

SECTION 1 An item of major concern becomes apparent in the listings on page 1~7 and

in Appendix F. While the number of LERs arising from personnel or procedural errors is not large, the safety significance of some of the events is substan-tial, particularly with regard to lpss of containment integrity and improper positioning of safety-related valves. These events extend over a sufficiently long period that is indicative of ~n indifference on the part of top management to take appropriate action. In my opinion the document does n~t stress this area sufficiently. Unless there is positive evidence of an improvem~nt in operator actions, I question approving a full-term operating license.

SECTION 2

- Explanatory only--no comments.

SECTION 3 The positive actions t~en to resolve issues III-6, VII-3, VIII-2, VIII-3B and VI-6 are considered appropriate. My personal opinion is that some ~f the changes under III-6 may not have contributed much to plant.safety.

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... e** *9 SECTION 4 In essence, this secti~n represents the action$ and bases. for the actions taken *including a factoring in of the PRA in Appendix B.

II-1-A no comment; no problem.

II-38, 81.C Pending; probable backfit.

I II-1 Positive actions that should provide missing information and enable decision as to acceptability of various items.

~III-2 - *A-good example of accepting alternate app~oaches when deviation-occurs. Instead of backfitting, it is recognized that sources of water can be made ~vailable. Emphasis is on clearly defined proce-dures covering use of alternate water source~ than on upgrading or i

backfitting.

III-3-C The positions of staff and utility are apparent. I would have th.ought this to be an economic problem that would become apparent during operation rather than under accident-conditions. I agree with staff.

III-4-A I applaud the decision not to backfit. It's approp*riate.

iII-5-A, III-6 I disagree on philosophic grounds with this item. In ten years of review I have yet to find a case where piping failed from seismic

loads and no breaks result from an unrealistic application of the design load cycles. Current analytic technique yield a false .. picture of piping response that seemingly is not recognized.

. "j III-7-A No disagreement--okay *

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111-7-B Primarily a bookkeeping .activity to provide analytic answers.

III-7-C *I understand the need to do another examination for delamination. I do not understand an arbitrary five-year repeat. We don't require that on embedded'f'iaw-s in vessels.

III-8-A May shift to generic.

V-5 -A realistic approach. I agree with staff analyses.

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. V-10-B Action tak~n resolves issue .

V-11-A This had potential to overpressurize and fail piping. The action only resol~es it partially since case of released flapper is not covered.

VI-2-D, VI-3 I agree with decision and PRA value. No action required.

VI-4 Removal of threaded piping is appropriate. Other decisions acceptable.

-VI-6 f-orced act i o*n taken--no issue.

VI-10-A No action.

VII-1-A* A good example of use of PRA to require revision or accept status quo ...

VII-3 DC power obviously is important. Basically handled as generic.prob-lem. Other actions based on a realistic assessment of tradeoffs.

VIII-3-A Important issue. Must assume loss of diesel generator plus offsite power.

VIII-4 Action taken.

IX-3 Presumably fix will be procedural in nature. Not clear. Second item procedural plus modification.

IX-5 Analytic only--not complete.

IX-6 In essence a generic backfit item.

-* XV-2 I am not surprised regarding the uncertainty in failure rates.

Basically, this will be handled generically.

XV-12 A ~ealistic approach to the problem.

With regard to equipment and design items, the authors addre?sed to a major degree the SEP task force* objectives as well as applying* the tiered cri-teria to resolve deviations. Generally, the approach is even-handled, riot requiring backfit arbitrarily. I am less satisfied with the handling of oper-

.ating history.

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, ' i; Appendix F points .out the high incidence of loss of power. This .combin*ed with some of the operator errors listed could yielq a definite degradation in safety margins.

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ML18047A328

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