ML20244E308
| ML20244E308 | |
| Person / Time | |
|---|---|
| Issue date: | 09/10/1986 |
| From: | Sniezek J Committee To Review Generic Requirements |
| To: | Stello V NRC OFFICE OF THE EXECUTIVE DIRECTOR FOR OPERATIONS (EDO) |
| References | |
| NUDOCS 8609230234 | |
| Download: ML20244E308 (38) | |
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UNITED STATES NUCLEAR REGULATORY COMMISSION o
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SEP 101986 I
MEMORANDUM FOR:
Victor Stello, Jr.
Executive Director for Operations FROM:
James H. Sniezek, Chairman Comittee to Review Generic Requirements
SUBJECT:
MINUTES OF CRGR MEETING NUMBER 95' The Committee to Review Generic Requirements (CRGR) met on Wednesday,
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August 27, 1986, from 1-3 p.m.
A list of attendees for this meeting is enclosed (Enclosure 1).
1.
L. Shotkin and J. Reyes of RES continued their CRGR review presentation on the matter of the proposed ECCS rule revisions (Section'50.46, Part 50) and changes to Appendix K to Part 50.
Pending a further consideration by CRGR of the actual rule language revisions now underway by RES, the CRGR favorably supported the staff's proposed course of action toward resolution of the several open issues that resulted from CRGR meeting No. 91. summarizes this matter (Category 2 item).
2.
R. Bernero (NRR) requested an opportunity to brief the CRGR members about activities being currently discussed with the BWR Owners' Group (BWROG) concerning severe accident management strategies to enhance accident mitigation capabilities" of the Mark I containment.
NRR is considering issuance of a generic letter on this matter in the near future.
CRGR provided no comments or recommendations on this matter.
summarizes this matter. contains predecisional information and, therefore, will not be released to the Public Document Room until the NRC has considered (in a public forum) or decided the matter addressed by the information.
In accordance with the ED0's July 18, 1983 directive concerning " Feedback and Closure on CRGR Reviews," item 1 above requir'es written response from the cognizant office to report agreement or disagreement with CRGR recommendations in these minutes.
The response, which is required within 5 working days after receipt of these meeting minutes, is to be forwarded to the CRGR Chairman and if there is disagreement with the CRGR recommendations, to the ED0 for decisionmaking.
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-j i SEP 101986 es 1 l Questions concerning these. meeting minutes should be referred to Walt Schwink (492-8639).
J.E. Zerbe for James H. Sniezek, Chairman Coniittee to Review Generic Requirements
Enclosures:
i-As Stated cc: Commission (5)
SECY
' Office Directors Regional Administrators CRGR Members t~
G. Cunningham i
L. Shotkin W. Beckner l
J. Reyes 1
!L Fleishman.
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LIST OF ATTENDEES CRGR MEETING NO. 95 August 27, 1986 CRGR MEMBERS J.H. Sniezek R. Bernero R. Starostecki (E. Jordan)
J. Scinto J. Heltemes R. Cunningham D. Ross OTHERS J. Zerbe M. Tay1or W. Schwink C. Thomas i
N. Lauben C. Berlinger J. Stewart M. Jamgochian M. Lesar P. Boehnert M. Fleishman L. Shotkin B. Morris K. Kniel W. Beckner J. Reyes 1
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- to the Minutes of CRGR Meeting No. 95 Proposed Revisions to 10 CFR 50.46 (ECCS Rule),
Appendix K and Associated Regulatory Guide (draft) i L. Shotkin and J. Reyes (RES) continued from Meeting No. 91,'the CRGR review presentation on the proposed ECCS rulemaking package. A copy of the vugraphs used in presenting this matter to CRGR is attached.
(Refer to the Minutes of 4
Meeting No. 91 for a more complete background on the proposed ECCS rulemaking package.) At Meeting No. 91, the CRGR concluded that the proposed ECCS rulemaking package was in need of further language revisions and that there were three open issues requiring additional staff consideration and development of regulatory positions.
Basically, these were:
1.
The potential impacts on licensees of elimination of the Dougall-Rohsenow correlation as an acceptable modeling feature of Appendix K.
i 2.
The appropriateness of the reporting requirements in the proposed rule.
This included the necessity for' and promptness with which each and every calculational error should be reported regardless of magnitude, the in-clusion of reporting requirements for applicants as well as the licensees, and the need for the staff to impose upon itself a 60-day response re-quirement for addressing these ECCS calculational errors.
- 3..
A determination by the Director of the Office of Research, in accord with CRGR Charter, whether the proposed rule actions would result in a decrease in the overall protection of public health and cafety and whether the proposal would result in cost savings for NRC and/or the industry.
By memorandum from the Acting Director of Research (dated August 19,1986),
these issues were formally addressed.
Regarding issue 1. above, concerning the Dougall-Rohsenow correlation and its proposed deletion from Appendix K, the staff expressed the view that with today's data and science available on ECCS performance and post-CHF correlations, it was not a good staff practice to continue to endorse by rule an outdated post-CHF correlation. While the staff noted that the Dougall-Rohsenow correlation could be made to give a better data fit by use of different correlating parameters, they would prefer its deletion from Appendix K.
As indicated in the attached vugraph copy, the staff has considered four potential options having various impacts on licensees.
For practical considerations, the staff has reached the conclusion that the option (Option 2) which permits existing Evaluation Models (EMS) to be " grandfathered" with the Dougall-Rohsenow correlation should be followed.
At the same time this option would remove the Dougall-Rohsenow correlations a generally I
acceptable feature from Appendix K.
It was the staff's overall judgment that l
the current ECCS EMS are sufficiently conservative, on the whole, to permit the continued use of this correlation in existing EMS.
For future modifications to EMS, including error corrections, the impact of continued EMS acceptability will be considered by the staff based on the overall conservatism of the eval-uation model.
If a new evaluation model is submitted, such as an EMS modified f
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because of errors or model revisions, or use of a new computer code, the ap-placability of the Dougall-Rohsenow post-CHF correlation would have to be ad-dressed. By this approach, the staff would intend to gradually phase out use of an outdated correlation while at the same time trying to minimize the impact to the licensees (and to NRC resources) by not requiring wholesale ECCS re-analyses at large costs.
The staff recognized that this option would still leave an inconsistency in the rule, but such a gradual phase-out was the preferred approach for minimizing the potential analysis burdens. After further discussion on the various proposed options, CRGR generally endorsed the staff's plans to proceed with Option 2 as described above.
CRGR further observed that it would be useful to develop a more specific standard of ac-ceptability to accompany Option 2 (e.g., an acceptable level of temperature increase to be allowed if continued use of the existing EMS with the Dougall-Rohsenow correlation were to be permitted) and recommended the staff work
~
toward this development.
Regarding the issue of reporting requirements, the staff expressed the view that the proposed ECCS rule revisions represent an improvement over the exist-ing ECCS rule that, as implemented, has resulted in the licensee to immediately report and correct all errors --even those that may be very minor.
The pro-posed ECCS rule revisions that were questioned by CRGR at Meeting No. 91 would reflect an NRR preference to be immediately informed of all errors, even minor, but would provide NRR with some flexibility on how quickly these errors are to be corrected. On the'other hand, RES believes all minor errors should be noted on a regular basis (such as annually).
Immediate and submitt'ed to the agency (less than a 50'F effect on calculated peak cladding reporting of minor errors temperature and not exceeding the 550.46(b) criteria) would not,be a require-ment.
CRGR expressed a generally favorable view toward'the proposed RES ap-i proach to this matter of reporting the minor errors.
However, CPGR noted that l
the RES staff would need to develop additional justification (or a rationale) to explain and support an NRC policy of allowing the knowledge of erroneous models to exist unreported for a period of up to a year.
Also, the cummulative effects of such minor errors should be addressej. The RES staff advised CRGR that information was at hand that could be relied upon to develop this addi-tional justification for periodic reporting of the minor errors.
Concerning the issue of whether the proposed rule would result in a decrease in the overall protection of public health and safety, it was the determination of the Office of Research that the proposed action would not result in any de-crease in plant safety because the conservative safety limits of 650.46(b) would not be reduced.
However, it was made clear by RES that while this action may not be considered a decrease in plant safety, it does represent a reduction 3
in margin introduced by the currently acceptable, yet overly conservative, cal-culational methods. On balance, RES expressed the view that using more realism in this matter should produce some safety benefit, albeit unquantifiable.
Re-garding costs, RES was of the view that most of the Westinghouse plants could potentially benefit from the proposed ECCS rule revisions should this option i
I 1
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for use of more realistic ECCS performance calculations be exercised.
An aver-age plant may be able to upgrade total power by an estimated 5% as a result of the proposed ECCS rule. This could result in lifetime energy replacement cost j
savings having a present value of between $70M to $100M. The estimated 3 to 4 i
staff years by NRC that would be needed to review the generically-based, rea-listic ECCS modeling submitted by vendors is believed to reasonably reflect the NRC cost expenditures. The staff resources are estimated to be adequate for this future review purpose.
In the overall, CRGR endorsed the above courses of action proposed by the staff to resolve those open issues from Meeting No. 91.
CRGR recommended that RES work with OGC in developing the final proposed ECCS rule language. When ready, RES ihould provide the CRGR with the revised rule package for a determination as to whether further CRGR review is needed.
/
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SEP 101986
.' c____/
-2 Questions concerning these meeting minutes should be referred to Walt Schwink (492-8639).
J.E. Zerbe for James H. Sniezek, Chairman Committee to Review Generic Requirements
Enclosures:
As Stated cc: Commission (5)
SECY-Office Directors Regional Administrators CRGR Members G. Cunningham L.~Shotkin W. Beckner J. Reyes M. Fleishman Distribution:
J5niezek JRoe JZerbe PRabideau JClifford GZwetzig ROGR Staff FHebdon WLittle EFox 3_
L RErickson 9
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Un eaek DATE :9/9/86
- 9//0 /86
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C *l UNITED STATES o,,
8 NUCLEAR REGULATORY COMMISSION o
h WASHi"1GTON, D. C. 20565 SEP 101986 MEMORANDUM FOR:
Victor Stello, Jr.
Executive Director for Operations FROM:
James H. Sniezek, Chairman Comittee to Review Generic Requirements
SUBJECT:
MINUTES OF CRGR MEETING NUMBER 95 The Comittee to Review Generic Requirements (CRGR) met on Wednesday, August 27, 1986, from 1-3 p.m.
A list of attendees for this meeting is enclosed (Enclosure 1).
1.
L. Shotkin and J. Reyes of RES continued their CRGR review presentation on the matter of the proposed ECCS rule revisions (Section 50.46, Part 50) and changes to Appendix K to Part 50.
Pending a further consideration by CRGR of the actual rule language revisions now underway by RES, the CRGR favorably supported the staff's proposed course of action toward resolution of the several open' issues that resulted from CRGR meeting No. 91. sumarizes this matter (Category 2 item).
2.
R. Bernero (NRR) requested an opportunity to brief the CRGR aembers about activities being currently discussed with the BWR Owners' Group (BWROG) concerning severe accident management strategies to enhance accident mitigation capabilities of the Mark I containment.
NRR is considering issuance of a generic letter on this matter in the near future.
CRGR provided no comments or recommendations on this matter.
summarizes this matter. contains predecisional information and, therefore, will not be released to the Public Document Room until the NRC has considered (in a public forum) or decided the matter addressed by the information.
In accordance with the ED0's July 18, 1983 directiva concerning " Feedback and Closure on CRGR Reviews," item 1 above requires written response from the cognizant office to report agreement or disagreement with CRGR recommendations in these minutes. The response, which is required within 5 working days a'fter receipt of these meeting minutes, is to be forwarded to the CRGR Chairman and if there is disagreement with the CRGR recommendations, to the EDO for decisionmaking.
]
a l
l d to the Minutes of CRGR Meeting No. 95 of Briefing to CRGR on the MatteF~of Severe Accident Management Strategies for the BWR Mark I Containment
.R. Bernero (NRR) provided a short briefing to the CRGR members on activities I
being currently discussed with the BWR Owners Group (BWROG).
These activities concern severe accident management strategies that may further enhance the severe accident mitigation capabilities of the Mark I containments. A copy of the vugraphs used for this briefing are attached.
R. Bernero noted that the Commission was advised on the overall safety objectives of this ongoing NRR n
activity. These objectives are:
I The likelihood of severe accident (core damage or core melt) should
~
be very low and, If a severe accident occurs, there should be substantial assurance that containment will mitigate its consequences.
Bernero pointed out that NRR anticipated the transmittal of a generic letter to l
licensees on this matter of the BWR Mark I containments in the near future.. A CRGR review would be expected. CRGR was also advised that this NRR activity is, being carried out pursuant to the Commission's policy statement on severe accidents. The severe accident management strategy currently being discussed with the BWROG involves five (5) principal elements'to enhance accident mitigation:
Prevent hydrogen combustion caused failure Use of containment spray water Avert overpressure failure (e.g., venting)
Reduce likelihood of failure by direct attack of core debris Through training and emergency procedures, ensure that operators are ready to use plant features to a best advantage in severe accidents.
CRGR offered no comments or recommendations as a result of this briefing; none was sought at this time.
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, to the Minutes of CRGR Meeting No. 95 of Briefing to CRGR on the Matter of Severe Accident Management Strategies for the BWR Mark I Containment l
R. Bernero (NRR) provided a short briefing to the CRGR members on activities being currently discussed with the BWR Owners Group (BWROG). These activities concern severe accident management strategies that may further enhance the severe accident mitigation capabilities of the Mark I containments. A copy of the vugraphs used for this briefing are attached.
R. Bernero noted that the Commiss w,was advised on the overall safety objectives of this ongoing NRR activity. These objectives are:
The likelihood of severe accident (core damage or core melt) should i
be very low and, If a severe accident occurs, there should be substantial assurance that containment will mitigate its consequences.
Bernero pointed out that NRR anticipated the transmittL! of a generic letter to licensees on this matter of the BWR Mark I containments in the near future. A CRGR review would be expected.
CRGR was also advised that this NRR activity is being carried out pursuant to the Commission's policy statement on severe accidents. The severe accident management strategy currently being discussed with the BWROG involves five (5) principal elements to enhance accident mitigation:
Prevent hydrogen combustion caused failure Use of containment spray water Avert overpressure failure (e.g., venting)
Reduce likelihood of failure by direct attack of core debris Through training and emergency procedures, ensure that operators are ready to use plant fe'atures to a best advantage in severe accidents.
CRGR offered no comments or recommendations as a result of this briefing; none was sought at this time.
'esSwo-cxc,emn rs SAFETY OBJECTIVES e
THE LIKELIHOOD OF SEVERE ACCIDENT (CORE DAMAGE OR CORE MELT) SHOULD BE VERY LOW AND e
IF A SEVERE ACCIDENT OCCURS THERE SHOULD BE SUBSTANTIAL ASSURANCE THAT THE CONTAINMENT WILL MITIGATE ITS CONSEQUENCES i
b O
s 6
l
a CONTAINMENT ISSUES J
e EARLY REACTORS LOW POWER / BIG CONTAINMENTS
.COULD MEET CONTAINMENT OBJECTIVE e
EVOLUTION OF DESIGN MUCH HIGHER POWER FOCUS ON PREVENTION OBJECTIVE CONTAINMENT GOOD FOR FISSION. PRODUCTS BUT QUESTIONS ABOUT HEAT AND GAS e
REACTOR SAFETY STUDY (1975)
BIGGER REACTORS
.1 PWR (SURRY) 1 BWR (PEACH BOTTOM)
BWR RESULTS INDICATED LOWER PROBABILITY BUT POOR CONTAINMENT 3
l e
E
l...
t
. US BWRS e
2 SMALL UNITS WITH LARGE CONTAINMENTS e
24 BWR 2/3/4 WITH MARK I CONTAINMENT (ALL LICENSED)
- e. 9 BWR 4/5 WITH MARK II CONTAINMENT (7 LICENSED) e 4 BWR 6 WITH MARK III CONTAINMENT (3 LICENSED) r e
e
~
---_.----_--___-___--_-_------.____._..-______---__..-_-_.-.__-.-_.__--___-_-________J
BWR CONTAINMENT IN SEVERE ACCIDENTS
- SINCE TMI l
c TMI ACTION PLAN I.C LETTERS OF SEPT-NOV, 1979 ON PROCEDURES BWR EPG, REV 1, REV 2, REV 3.,
REV 4 e
IDCOR-ANALYSIS
.IDCOR FOUNDED DECEMBER 1980 STILL DELIBERATING ANALYSIS WITH NRC e
NRC/ CONTRACTOR ANALYSIS SOURCE TERM STUDIES SARRP - WHAT WILL NUREG-1150 SAY?
BNL GUIDELINES AND CRITERIA e
CHERNOBYL UNIT 4 HAD PRESSURE SUPPRESSION CONTAINMENT FEATURES -
A STRIKING RESEMBLANCE?
WHAT ARE THE PROBLEMS AND SOLUTIONS d
e 5 ELEMENTS TO CONSIDER HYDR 0 GEN SPRAYS PRESSURE CORE DEBRIS TRAINING & PROCEDURES e
e MANY CHANGES ARE ALREADY IN PLACE
?
e FINAL IMPROVEMENTS ARE NOW UNDER HIGH PRIORITY STUDY GENERIC ACTION WITH IDCOR AND BWROG GENERIC WORK BY NRC VERMONT YANKEE STUDY PILGRIM PROGRAM 1
6 I
CHRON0 LOGY e
JUNE 16, 1986:
MEETING WITH BWROG/IDCOR PROPOSED A GENERIC LETTER, PRESCRIPTIVE SOLUTION, BY BACKFIT e
JUNE 30, 1986:
VERMONT YANKEE COMMITS TO GOV, KUNIN TO DO A SPECIAL 60-DAY CONTAINMENT STUDY e
JULY 25, 1986:. BOSTON EDISON COMPANY BOARD DECIDES TO FIX PILGRIM CONTAINMENT e
AUGUST 19, 1986:
BWROG EXECUTIVES VOTE TO FUND AND CONTINUE DIALOGUE ON THIS WITH NRC, CONTACT NUMARC ABOUT BWR VS, PWR e
SEPTEMBER 11, 1986:
MEETING WITH BWROG TO COMPARE BACKFIT NOTES AND STRAWMAN GENERIC REQUIREMENTS e
SEPTEMBER 11, 1986:
MEETING WITH VERMONT YANKEE TO REVIEW CONTAINMENT STUDY
~
e SEPTEMBER 23, 1986:
NRC/IDCOR MEETING ON BWR/ MARK I ANALYSES e
SEPTEMBER 23, 1986:
ACRS SUBCOMMITTEE ON CONTAINMENT PERFORMANCE TO DISCUSS HARPERS FERRY WORKSHOP RESULTS AND BWR CONTAINMENT GENERIC APPROACH e
SEPTEMBER 24, 1986:
ACRS SUBCOMMITTEE ON CLASS 9 ACCIDENTS TO DISCUSS BWR/ MARK I ANALYSES AND SEVERE ACCIDENT PROGRAM e
NOVEMBER 19, 1986:
CRGR REVIEW 0F DRAFT GENERIC LETTER ON BWR CONTAINMENT REQUIREMENTS (T0 BE PUBLISHED FOR COMMENT) e DECEMBER 17, 1986:
ISSUE DRAFT GENERIC LETTER ON BWR CONTAINMENT REQUIREMENTS FOR PUBLIC COMMENT e
APRIL 1987:
ISSUE FINAL GENERIC LETTER ON BWR CONTAINMENT REQUIREMENTS i
DISCUSSION
.e BWR MARK I CONTAINMENTS APPEAR TO BE MOST VULNERABLE e
ANALYTICAL PROCESS IS VERY SLOW I-IDCOR/NRC-DIALOGUE 2-IPE METHODOLOGY SUBMITTED 3-IPE METHODOLOGY APPROVED 4-IPE GUIDELINES AND CRITERIA DEVELOPED
~
5-IPE GUIDELINES AND CRITERIA APPROVED 6-PROGRAM REVIEW WITH COMMISSION
~
7-PLANT-BY-PLANT CONDUCT OF IPE 8-PLANT-BY-PLANT SUBMITTAL OF IPE RESULTS AND PROPOSED CHANGES
~
~
9-NRC REVIEW OF IPE RESULTS AND PROPOSED CHANGES 10-NRC ORDER, AS REQUIRED, TO IMPLEMENT NEEDED CHANGES 11-IMPLEMENTATION O
O O
e
___.-_____.______-__-----_________-___-.-a
G SLIDES EnDi'l JUNE 16, 1986 MEETING WITH BWROG 6
a
1
', * :i.
l NRC SEVERE ACCIDENT POLICY e
FUTURE PLANTS STANDARD.
CONVENTIONAL REVIEW PRA e
EXISTING PLANTS THEY ARE SAFE EN0 UGH IDCOR PROCESS IS NEEDED
~
INDIVIDUAL PLANT EVALUATIONS GENERIC TREATMENT FOR GENERIC MATTERS
i.
TWO ACTIVITIES
~
e DEVELOPMENT OF EMERGENCY OPERATING PROCEDURES SCOPE:
PREVENTION AND MITIGATION EPG --+ PGP
> E0P NOW ON EPG REV. 4 e
IDCOR IPE SCOPE:
PREVENTION AND MITIGATION fiETHODOLOGY ---+ IPE PROGRAM
>IPE METHODOLOGY BEFORE NRC e
COMMON FACTORS ARE IMPORTANT SCOPE PLANT / EVENT ANALYSIS 1
.__--_-_- ____ -_ L
EE 1
L 3
)
i'[G, i
l' I
CONCERNS e
E0P WHAT ARE THE E0P STRATEGIES?
WHAT ARE MINIMA TO TRANSFER FROM EPG ----> PGP
> E0P?
~
ARE REQUIREMENTS CLEAR?
e IDCOR IPE IS IT AN ASSESSMENT OR AN EVALUATION?
SHALL EACH OWNER ENTER THE IPE WITH A BLANK SLATE?
ARE THERE ANY GENERIC SOLUTIONS OR STRATEGIES EV 4
PRIORITIES?
y i
s.
d RECALL WASH-1LiOO e
BWR VS PWR PROBABILITY OF CORE MELT BWR C PWR CONSEQUENCES OF CORE MELT BWR >
.PWR e
BWR CHARACTERISTICS
-5 BWR-3 2 x 10 TC-g TW-7 6 x 10-6' BWR-2 TW-g' 9
4 4
- - - - - - - - -. _ _ _ _ _ _ _ _, _ _ _ _ _ _ _ __of____
o
+.,.., ',
Q A 5 ELEMENT POLICY 1.
HYDROGEN 2.
SPRAYS 3.
PRESSURE 4.
CORE DEBRIS 5.
TRAINING AND PROCEDURES 4
e
d ELEMENT 1 - HYDROGEN OBJECTIVE:
PREVENT HYDROGEN COMBUSTION CAUSED FAILURE r
REQUIREMENTS:
A.
OXYGEN CONTROL INERT TO START CONTROL INGRESS OF OXYGEN B.
HYDROGEN CONTROL CONTROLLED BURNING EQUIPMENT SURVIVABILITY ISSUES:
1.
WHEN AND HOW LONG'NOT INERTED 2.
INDEPENDENT POWER FOR IGNITERS 3.
SURVEILLANCE FOR IGNITERS l
1 9
6
___.___________.s
7
[
ELEMENT 2 - SPRAYS s
OBJECTIVE:
SPRAY WATER T0:
1.
LOWER PRESSURE 2.
COOL VULNERABLE EQUIPMENT 3.
QUENCH DEBRIS 4.
SCRUB AEROSOLS REQUIREMENTS:
1.
SPRAY IN DRYWELL 2.
BACKUP WATER SOURCES AND PUMPS HOSE CONNECTIONS USE OF FIREMAINS ISSUES:
1.
RISK OF IMPLOSION 2.
RISK OF HYDROGEN COMBUSTION AFTER STEAM CONDENSATION 3.
MANUAL ACTIONS AND TIMING 9
8
- i. -
1 ELEMENT 3 - PRESSURE j
OBJECTIVES: 1.
AVERT UNCONTROLLED OVERPRESSURE FAILURE 2.
CONTROL RELEASE PATH (SCRUBBING)
Rt00lREMENTS:
1.
SUBSTANTIAL CAPABILITY TO VENT WETWELL 2.
REMOTE / RELIABLE CONTROL OF VENT VALVE 3.
ABILITY TO RECLOSE VENT ISSUES:
1.
DELIBERATE RELEASE OR RADI0 ACTIVITY 2.
WHAT IS REMOTE / RELIABLE CONTROL?
3.
IS DUCT BURST IN SECONDARY CONTAINMENT ACCEPTABLE?
4.
WHAT IS APPROPRIATE ACTION PRESSURE?
9
9
., i,.
ELEMENT 4 - CORE DEBRIS i
1 OBJECTIVE:
REDUCE LIKELIHOOD OF FAILURE BY DIRECT ATTACK REQUIREMENTS:
1.
USE PRACTICAL DEBRIS RETARDING BARRIERS 2.
CONSERVE SUPPRESSION POOL WATER AS A QUENCHING P0OL ISSUE:
WHAT IS PRACTICAL?
i 4
10 t
ELEMENT 5 - TRAINING AND PROCEDURES I
OBJECTIVE:
ENSURE OPERATORS ARE READY TO USE PLANT FEATURES TO BEST ADVANTAGE IN SEVERE ACCIDENTS REQUIREMENTS:
1.
CLEAR SYMPTOM BASED STRATEGIES (INTEGRATED) 2.
REMOVAL OF UNNECESSARY INHIBITIONS 3.
TRAINING / PROCEDURES ISSUES:
1.
COMPETING SAFETY REQUIREMENTS 2.
DEGREE OF TRAINING
+p gg er t?:.* 3 AN INSTITUTIONAL APPROACH l
e GENERIC LETTER - ADVANCED NOTICE OF. PROPOSED REQUIREMENTS - TO SOLICIT COMMENT l
~
e COLLECTIVE PUBLIC REVIEW e
GENERIC LETTER OF REQUIREMENTS
IMPLEMENTATION '
L._