ML20247G253
| ML20247G253 | |
| Person / Time | |
|---|---|
| Site: | Vermont Yankee File:NorthStar Vermont Yankee icon.png |
| Issue date: | 03/21/1989 |
| From: | Murphy W VERMONT YANKEE NUCLEAR POWER CORP. |
| To: | |
| Shared Package | |
| ML20247G246 | List: |
| References | |
| NUDOCS 8904040176 | |
| Download: ML20247G253 (236) | |
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ECR !ERMEON GU VERMONT YANKEE PROCEDURE GENERATION PACKAGE (PGP)
Revision 3 February 1989 l (
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Db-Operations Supervisor approved: e 87/7 2/23/M
- 0 approved: MI~- - S// /8r Want Manager approved:. ... db Yk+7)b Jh//fV
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TABLE OF CONTENTS page ,
1.0 INTRODUCTION
1 1.1 Purpose 1 1.2 Scope 1 1.3 Organization 1 1.4 References 1 2.0 PLANT-SPECIFIC TECHNICAL GUIDELINES 2 2.1 General 2 2.2 Program Description 2 3.0 EMERGENCY OPERATING PROCEDURES (EOPs) 3 3.1 General 3 3.2 Program Description 4 ;
4.0 OE WRITERS' GUIDE 6 4.1 General 6 $ )
4.2 Document Description 6 5.0 REVERIFICATION PROGRAM 7 3 5.1 General 7 5.2 Program Scope 7 5.3 Program Objective 7 5.4 Program Description 7 6.0 OEVAUDATION PROGRAM 8 6.1 General 8 6.2 Program Scope 8 6.3 Program Objective 8 6.4 Program Description 9 7.0 OETRAINING PROGRAM 9 7.1 General P 7.2 Program Descript!on 9 7.3 Training Program Goals 9 7.4 OE Training Methods 9 1 7.5 Traininq on OE Revisions 10 l 8.0 PGP REMSIONS 11 !
11 I 8.1 Responsibilltv 11 I 8.2 Description of Method l Appendix A: Plant Specific Technical Guidelines (PSTGs)
Append!x B: Operational Emergency Procedures Writers' Guide Appendix C: OE Validation Using Table-Top Method Appendix D: OE Validation Using Walk Through Method Appendix E: OE Validation Using Simulator Method Appendix F: Simulator Debriefing Guidelines l Appendix G: Justification of Deviations, Deletions, and Additions (JDDA) l l
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Procedure Generetion Prckroe (PGP) DC 1
1.0 INTRODUCTION
1.1 Purnose The purpose of this Procedures (Change) Generation Package (PGP) is to describe the methods to be used to upgrade or change the Emergency Operating Procedures (EOPs) at the Vermont Yankee Nuclear Power Plant. j The EOPs are designated as Operational Emergency Procedures (OEs) and are referred to as OEs in this document.
1.2 Scope This document was developed from the Procedures Generation Package Controlled Document (Rev. 0) which was written in response to Supplement 1 to NUREG-0737, item 7.2b using Reference 1.4.b. as a guide. Reference 1.4.c. has been incorporated into Rev. 3.
This document describes the EOP revision process, the PGP revision process, and the method used M ensure all steps in the EOPs, which are different from the BWROG EOP Technical Guidelines, are documented and adequately reviewed. ;
The process described herein also incorporates the guidelines and objectives of the Control Room design review process.
1.3 Organization This document consists of the following eight parts:
- a. Introduction
- b. Plant Specific Technical Guidelines l c. Emergency Operating Procedures (EOPs)
- d. OE Writer's Guide
- e. OE Verification Program
- f. OE Validation Program
- g. OE Training Program l h. Procedure Generation Package (PGP) Revisions Each part describes the approach taken as part of the overall OE implementation Plan for Vermont Yankee.
1.4 References
- a. NUREG-0737, Supplement 1, item 7, " Upgrade Emergency Operating Procedures (EOPs)"
- b. INPO 82-017, " Emergency Operating Procedures Writing Guideline"
- c. NUREG-0899, " Guidelines for the Preparation of Emergency Operating Procedures"
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Procedure genertion P ck"ce (PGP) og 2 2.0 PLANT-SPECIFIC TECHNICAL GUIDELINES 2.1 General The following methodology for converting the BWR Owners Group (BWROG) Emergency Procedure Guidelines (EPGs) into Plant Specific Technical Guidelines (PSTGs) has been developed and is used by Vermont Yankee.
The EPGs, Revisloc 3, was used for the implementation of the OEs. The following major items were considered in the conversion of the EPGs into PSTGs:
- a. Plant-specific technical information.
- b. Lessons learned via simulator validation and verification.
- c. The use of other plant EOPs.
- d. Documentation requirements,
- e. Basis informs. tion supplied with the EPGs.
It is intended that all future revisions to the PSTGs will continue to be written and reviewed with these points in mind.
2.2 Procram Description "
- a. Responsibility Revisions to the PSTGs are the responsibi;ty of the Operations Supervisor.
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. b. Preparation Documents To prepare the draft revision. the Operations Supervisor or a person designated by him utilizes the fonowing p' ant-specific technical information (Source Documents) as necessary:
1 ) BWROG EPGs and related inforraation as appropriate 2 ) Vermont Yankee FSAR 3 ) Vermont Yankee Technical Specifications 4 ) Current plant drawings 5 ) Plant operating procedures 6 ) EDCR, PDCR, PAR Descriptions 7 ) Plant Specific Reports and Analysis
- c. P, reparation / Approval of Revisions The revision approval cycle is controlled by the Operations Supervisor. If necessary, the changes may be shown in ' rough-draft' format during the initial review and approval process. (Section 2.2.e, Steps 15).
The PSTG revision follows the intent of the EPGs, adding plant specific information where necessary using the appropriate source documents. Any exceptions to the EPGs which are taken in the PSTGs are documented and added to the Justification of Deviations, Deletions, and Additions (JDDA), Appendix F, prior to implementation of the EOP revision.
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- d. Discrepancies / Suggestions Found During Review Process
.ll,ls the responsibility of the Operations Supervisor to resolve any
- recommendations made during the review process with the person making the
-recommendation. Prior to submittal to PORC, all such comments must be resolved.
- e. PSTG Revision Review Path OE revisions and any deviations from the EPGs follow the following path during the review process as a minimum: ,
- 1) Originator (writer) of revision
- 2) Senior Operations Engineer
- 3) Operations Supervisor
- 4) Operations Superintendent
- 5) Senior Operations Engineer (comments resolution)
- 6) PORC
- 7) Plant Manager
- 8) Manager of Operations
- f. Implementation 4
When a PSTG revision receives final approval from the Manager of Operations;it is implemented via section 3 of this document. #
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- g. Distribution ,
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- a. Official versions of the PSTGs are distributed according to the distribution list maintained fcr this controlled document.
3.0 EMERGENCY OPERATING PROCEDURES (EOPs) 3.1 General The following methodology for converting the PSTGs into OEs has been developed and is used by Vermont Yankee.
The following major items are considered in the revision process:
- a. location and type of controls, equipment, and indications.
- b. Units of measure and scales for parameter indications.
- c. Equipment designation (labeling).
- d. Shift manpower, qualifications, training, and experience.
t The use of other plant EOPs.
- f. Documentation requirements.
it is intended that all future revisions to the OEs will continue to be written and reviewed with these points in mind.
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Procedure Generation Packsoe (PGP) og 4 3.2 Prooram Description E' l a.- [ Responsibility )
Revisions to the OEs are the responsibility of the Operations Supervisor,
- b. Preparation Documents To prepare the revision, the Operations Supervisor or a person designated by him .
utilizes the following piant-specific information (Source Documents) as necessary: ,
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1 ) PSTGs '
2 ) Plant-specific EOP calculations 3 ) Vermont Yankee OE Writers Guide 4 ) Plant operating procedures
- c. Preparation / Approval of Revisions The revision approval cycle is documented on the EOP Revislod C'hecklist (contained in Appendix B) and is controlled by the Operations Supervisor. If k necessary, the changes may be shown in ' rough-draft' format during the initi(
l review and approval process. (Section 3.2.e, Steps 1-5) T The Operations Supervisor is responsible for ensuring that the verification and ~
l validation requirements described in Section 5 and 6 respectively of this document
) are satisfied, and resoMng all discrepancies prior to subrnitting the procedure to the plant management review process described in AP 0831. The EOP Revision Checklist accompanies the procedure revision through the review cycle,
- d. Discrepancies / Suggestions Found During Review Procesc 11 is the responsibility of the Operations Supervisor to resolve any recommendations made during the review process with the person making the recommendation. Such discrepancies and recommendations are documented either on the EOP Revision Checklist, or the copy of the EOP which is being reviewed.
l i Prior to submittal to PORC, all such comments must be resolved.
- e. Procedure Revision Review Path OE rovisions and any deviations from the EPGs follow the following path during the review process as a minimum:
- 1) Originator (writer) of revision
- 2) Senior Operations Engineer
- 3) Operations Supervisor
- 4) Verification and Validation
- 5) Operations Superintendent
- 6) Senior Operations Engineer (comments resolution)
- 7) PCFC
- 8) Plant Manager O
Procedure Generrtion Ps&oe (PGP) og $
- f. Implementation
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l n an OE revision receives final approval from the Plant Manager, a clean copy
.@f o the procedure is drawn which reflects all approved changes and submitte i inilowing for approval signatures only: {
1 ) Operations Supervisor 2 ) PORC Secretary 3 ) Plant Manager
- g. Distribution l
- a. Official versions of the EOP flow diagrams and appendices (in notebooks) are distributed according to the distribution list maintained in the Main Office by i the Procedures Administration Assistant. '
- b. Color enhanced. mounted versions of the flow diagrams are maintained in the following locations:
1 ) Control Room '
2 ) Simulator -
3 ) TSC -
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Procedure Gew' tion Packroe (PGP) 90 8 4.0 QEERITERS' GUIDE 4.1 fa80RISI The OE Writers' Guide provides specific. detailed instructions on writing OEs and l flowchart guidelines. In addition to establishing sound writing principles, the guide l promotes consistency among all OEs and their revisions, independent of the OE writer.
The Writers' Guide is based on the industry document " Emergency Operating Procedwes Writing Guideline" (INPO 82-017), developed by the EOPIA Review Group and I published by INPO, and NUREG 0899 " Guidelines for the Preparation of Emergency Operating Procedures".
4.2 Document Description Information on the following ma}or items is included in the plant-specific Writer's Guide:
a Flowchart Guidelines e
- b. Appendices Guidelines
- c. Mechanics of Style h"
- d. EOP revision control y The Vermont Yankee Operational Emergency Procedures Writers' Guide is provided as
, Appendix B.
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Procedure Generation Pade ce (PGP) og 7 i
l 5.0 OE VERIFICATION PROGRAM Mm 5.1 Genarmi OE verification is the evaluation performed to confirm the written correctness of the procedure and to ensure that applicable generic and plant-specific technical information has been incorporated properly. This evaluation also checks that the human factors aspects presented in the Writers' Guide for OEs have been applied. The verification that a corresporsdence existed between the procedures approved for initial implementation -
and Control Room / Plant hardware was performed as part of the VY Detailed Control Room ,
Design Review (DCRDR) referenced in FVY84-64 issued 6-19-84 entitled 'Vermor t l Yankee Detailed Control Room Dssign Review (DCRDR) Program Plan". If continued correspondence cannot be verified, c new DCRDR may be initiated.
5.2 Proaram Scooe In performing the verification of an OE revision, consideration of the following items are necessary:
- a. How OE verification WHI be performed, and by which individual or group.
- b. How completion of the OE verification process will be documented.
- c. What process will be used in resolving discrepancies. j
- d. The specific source documents to be used for reference. (
5.3 Procram Objective To verify that the information presented in the OEs is correctly incorporated and is ,
consistent with the qualifications, training and experience of the operators. Verification is performed by a member er members of the Operations Department assigned by the l Operations Supervisor and will be performed as an integral part of the procedural review process. The EOP Revision Checklist attached to each procedure during the review process serves as documentation that the objective has been met. Any comments generated during the above review shall be resolved by the Operations Supervisor.
5.4 Procram Description
- a. Verify that the procedure changes are technically correct in that they accurately reflect the plant specific technical guidelines and other pertinent source documents,
- b. Verify that the procedures are constructed correctly in that each procedure continues to accurately reflect the Vermont Yankee Procedures Generation Package (PGP) and the Writers' Guide contained therein.
- c. Verify any calculations performed in the generation of the procedure. Methodology and control of calculations will be performed per plant procedure for calculations l and analysis. I
- d. Ensure that any deviations generated in the conversion of the Boiling Water Reactor (
Owners Group (BWROG) Generic Technical Guidelines to the Plant Specific {
Procedure as a result of the revisions, are noted and proper justification for the I deviation supplied. I l
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~ Procedure Generagon Padaos (PGP) as 8
. vy 6.0 OE DATION PROGRAM Jir 6.1 Gangal .
OE validation is the evaluation performed to determine that the actions specified in the procedure can be performed by the operator to manage the emergency conditions .
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effectively. The OE validation evaluates the operator's Obility to manage emergency conditions using the OEs and that the Control Room hardwaii, l& adequate to implement the procedure, it can be used to validate OE procedure changec if validation is deemed necessary by the Operations Supervisor. Validation is not necessary ior minor revisions.
6.2 Proaram Scope in developing an OE validation, the following major items are considered:
- a. How OE validation will be performed. Q 4
- b. How to use simulators, walk throughs, or table-top methods of validation.
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- c. How operating and training experience will be irdegrated into the program 2 4 evaluation. M 7~
- d. The evaluation criteria to be applied and the methods to be followed in resolv discrepancies. J
- e. How completion of the OE validation process will be documented. % pS
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6.3 Proaram Oblective The validation program is designed to ched the changes made to the Emergency Operating Procedures to ensure that the following criteria are maintained:
- a. The iOEs are usable. (i.e., They can be understood and followed with a minimum of confusion, delays, and errors.)
- b. A correspondence exists between th(. procedures and the Control Room / Plant i hardware:
1 ) Controls, equipment and indications referenced are available and located where ,
they wlR be needed. )
2 ) The same designations are uaed.
3 ) The same units of measure are used.
4] The equipment operates as specified in the procedure.
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- c. No language and level of information presented in the OEs is consistent with the i shift manpower, qualifications, training, and experience of the operating staff.
- d. Assurance that the procedures will work. (i.e., That the procedures guide the operator in mitigating transients and accidents.)
w 1 Procedure Generadon Padraoe (PGP) on 9 6.4 Progrega Description eM A des"e$ tion of the methodologies of Table-Top Validatior;, Walk-Through Validation, and Shnulator Validation are provided as Appendices C, D and E, respectively.
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The results of the validation shall be summarized in a memo to the Operations l Supervisor. If no validation is deemed necessary, this will be indicated on the EOP Revision Checklist.
7.0 OE TRAINING PROGRAM 7.1 General ,
OE training is a vital element in the overall operator training program at Vermont '
Yankee. A unified effort on the part of the Training Department and the OE writers results in operators who are knowledgeable in both the use and the intent of these~r procedures. g{ , {
Not all revisions will require formal training. This will be determined by the ,
Operations Supervisor and depend on the extent and magnitude of a revision. ?, M e -4 > y 7.2 Procram Description g In developing training in the area of OE revisions, the following major items are ]
[] considered: j
- a. What type of operator training should be provided.
- b. What method of operator training should be followed.
- c. What operator knowlecha and skill level is required.
- d. What procedure tasks exist that require operator decision-making.
- e. What training materialis needed to support OE training requirements.
- f. What current operator licensing requirements or guidelines axist.
7.3 Trainina Procram Goals The overall training goals for training in OE revisions are as follows:
- a. To enable the operators to understand the structure of the OEs.
- b. To enable the operators to gain an understanding of the technical basis of the OE h
- c. To enable the operators to have a working knowledge of the technical content of the OE du:nges.
- d. To enable the operators to use the OEs under emergency conditions.
7.4 OE Trainino Methods As part of the training program, OE training will be included to establish an operations staff which is capable and competent to respond to any off-normal plant situation. This 3
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g Pr%re Generation Padace (PGP) Da 10
- training may consist of classroom instruction, Control Rc,om wak-throughs, and/or Simulegor exercises;
!N a.4 Sessroom Instructions x
Annual classroom retraining sessions will be conducted and will include the .3 following:
1 ) A discussion of the OE flow diagrams, including their basis and supporting information.
2 ) A discussion of the use of the various graphs on the flow diagrams. ,
3 ) The OE appendices.
- b. Self-Help Supplementation Classroom instruction may be supplemented by self-help techniques. Self-help essentially entails having the operators review and study the information presented in the classroom instruction via required readings. They can also implement self-help during shifts when they are not performing required duties.
- c. Walk-Throughs i
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- d. An important part of the instruction on OEs is the practical experience gainedi O' N through procedure walk-throughs in the Control Room or Simulator. During i ils i' method of training, the team approach to using OEs is stressed. This wak-thro $h.
training also concentrates on information flow and interactbns of the operators in the Control Room. ., <
P-h e. Simulator Exercises Training on OEs is conducted for all licensed operators using scenarios on the simulator and is conducted with all operators performing their normal Control Room functions. Additional training is also conducted if the members of a crew alternate responsibilities. This additional training promotes understanding of the other operator's responsibilities in the overall conduct of the actions, and leads to enhanced communications within the Control Room.
7.5 Trainina on OE Revisions Depending on the magnitude of the OE revision, the Training Department may utilize any or all of these training methods, or a memo addressed to all licensed operators (if the change is minor) may be distributed by the Operations Supervisor. {
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Tra should be conducted as close to the end of the revision approval process as feas to ensure that training is not conducted on a procedure which is subsequently I changed as a result of the review process. If necessary, implementation of a revision will be delayed until there is operator confidence in the new procedure, as revised.
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Procedure Gener^ tion Packsoe (PGPL 90 11
- k; 8.0 PGP REVISIO_ tis s
8.1 Resnonsibilltv a Any changes to this PGP is the responsibility of the Operations Supervisor.
- b. Use the PGP revision sheet to indicate approval of changes.
8.2 Description of Method a The Operations Supervisor, or someone assigned by him, indicates the desired changes.
- b. Changes between the present revision and the new revision will be indicated by a vertical line In the left-hand margin.
- d. The Plant Manager and Manager of Operations approve the revision once any comments have been resolved.
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APPENDIX A
.Ik VERMONT YANKEE l PLANT SPECIFIC EMERGENCY PROCEDURE TECHNICAL GUIDELINE (based upon BWROG EPGs, revision 3)
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Vermont Yankee PSTG pape 2 1 l
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INTRODUCTION l Based on the BWR Owners Group Emergency Procedures Guideline (EPGs) Revision 3, the following plant-specific symptomatic emergency procedure guidelines have been developed:
o RPV Control Guideline -
o Suppression Chamber Control Guideline o Drywell Control Guideline o Secondary Containment Control Guideline i
The RPV Control Guideline maintains adequate core cocling, shuts down the reactor, and cools down the RPV to cold shutdown conditions. This guideline is entereo whenever low RPV wcter level has occurred, or whenever a condition which requires reactor scram exists and reactor power is above the APRM downscale trip or cannot be determined. ,
The Suppression Chamber and Drywell Contro! Guidelines maintains primary -
,' l containment integrity and protects equipment in the primary containment. The i .I s Suppression Chamber guideline is entered whenever suppression pool temperature i r {
suppression pool water volume is abovo its high operating limit or suppression pool : i water volume is below its low operating limit. The Drywell guideline is entered f j, whenever drywell temperature is above its high operating limit, or pressure.is above q its Tec ~ Spec LCO.
The Secondary Containment Control Guideline protects equipment in the secondary '
containment, limits radioactivity release to the secondary containment, and either maintains secondary containment integrity or limits radioactivity r6 lease from the secondary containment. This guideline is entered whenever a secondary containment temperature, radiatiot level, or water level is above its maximum ncrmal operating value or a secondary containment floor drain sump is in continuous opemtion. l Table I is a list of abbreviations used in the guidelines and procedures.
At various points throughout these guidelines, precautions are noted by the symbol '"#".
The number within the box refers to a numbered Caution contained in the Operator Precautions section. These " Cautions" are brief and succinct red flags for the operator.
At various points within these guidelines, limits are specified beyond which certain actione.are required. While conservative, these limits are derived from engineering analyses utilizing best est! mate (as opposed to licensing) models. Consequently, these limits are not as conservative as the limits specified in a plant's Technical Specifications. This is not to imply that operation beyond the Technical Specifications is 3 recommended in an emergency. Rather, such operation may be required under certain {
degraded conditions in order to safely mitigate the consequences of those degraded {
conditions. The limits specified in the guidelines establish the boundaries within which q continued safe operation of the plant can be assured. Therefore, conformance with the guidelines does not ensure strict conformance with a plant's Technical Specif' cations or other licensing bases.
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3 Vermont Yartee PSTG k page 3 1
-, The entry conditions for these emergency procedure guidelines are symptomatic of both eT ---M and events which may degrade into emergencies. The guidelines specify opriate for both. Therefore, entry into procedures developed from these gu . .is not conclusive that an emergency has occurred.
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Vermont YO:kee PSTG pape 4 m- TABLEI )
- .d ABBREVIATIONS
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ADS Autom&fc Depressurization System ALT Alternate APRM Average Power Range Monitor ;
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ARI Alternate Rod Insertion 00 Control Rod Drive -
CFF Control Room Panel GT Condensate Storage Tank CUFD Cleanup Filter Domineralizer D/G Emergency Diesel Generator (s)
ED3 Emergency Core Cooling System ED Emer0ency Depressurization j FDW Feedwater :
HCU Hydraulic Control Unit HPCI H6gh Pressure Coolant injection HVAC Heating, Ventilating and Air Conditioning /
INJ injection -
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IRM Intermediate Range Monitor .
Umiting Condition for Operation
- LOO ll LOCA 1.oss of Coolant Accidelit x LPCI Low Pressure Coolant injection .
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G t.ow Pressure Core Spray % e J; MSIV Main Steam;ine isolation Valves ~T A MSL Main Steam Line !
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- NPSH Not Positive Suction Head G Operational Emergency procedure CP Operating Procedure PCIS Primary Containment Isolation System PTS Points RCIC Reactor Core isolation Cooling RECIRC Recirculation Rm Residual Heat Removal RHRSW RHR Service Water RPS Reactor Protection System RPT Recirculation Pump Trip FFV Reactor Pressure Vessel FRJ Reactor building Recire Unit y RWCU Reactor Water Cleanup jff Rx Reactor
~y' S 318 S/D Standby Gas Treatment System Shutdown SN Scram Discharge Volume S,lAE Steam Jet Air Elector SLC Stan&y Liquid Control SRM Source Range Monitor SRV Safety Relief Valve TAF Top of Active Fuel TRMS Transformer
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Vermont Yankee PSTG page 5 l
l OPERATOR PRECAUTIONS 1 I GENERAL This section lists Cautions which are generally applicable at all times.
CAUTION #1 Monitor the general state of the plant. If eri entry condition for other OE occurs, enter that procedure.
CAUTION #6 lDrywell temperature affects level indication. l Call JON #8 Observe NPSH requirements for pumps taking suction frorn the lorus. j REQUIRED NPSH CURVE A a0 , g j-70 }l
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100 150 200 250 300 350 400 Torus Water Temperature (*F) w CAUTION #9.
If signals of low CST level occur, consider / verify transfer of HPCI and/or RCIC suctions from the CST to the suppression pool.
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Vermont Yankee PSTG pape 6 3
CIFIC- .
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. ,section lists Cautions which are applicable at one or more specific points within thel guidelines. Where a Caution is applicable, it is identified with the symbol T.
CAUTION #10 Do not secure or place an ECCS in manual mode unless, by at least two independent indications, misoperation in AUTOMATIC mode is confirmed, or adequate core cooling is assured.
CAUTION #11 if a high drywell pressure ECCS initiation signal occurs or exists while depressurizing, prevent injection from those Core Spray and LPCI pumps not recuired to assure adeauste core coolina.
CAUTION #12 lDo not throttle HPCI or RCIC systems below 2200 rpm. J !
CAUTION #13 i lCooldown rates above 100'F/hr may be recuired to accomplish this step. E lji f
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3 CAUTION #14 Do not depressurize the RPV below 150 psig unless motor driven pumps sufficient to g maintain RPV water level are running and available for iniection.
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CAUTION #15 lOpen SRVs in secuence to distribute torus heat loadina. l CAUTION #16 ,
IBypassina interlocks may be required to accomplish this step. l CAUTION #18 if continuous LPCI operation of any RHR pump is required to assure adequate core coolina, do not divert all RHR pumps from the LPCI mode.
CAUTION #19 IManually trip SLC pumps at 0% tank level to insure future availability. l s CAUTION #22 IDMc isolation interlocks may be required to accomplish this step. I CAUTION #23 lDo not initiate drywell sprays while torus level is above 22.4 feet. I CAUTION #24 Bypassing high drywell pressure and low RPV water level for the reactor building HVAC isolation interlocks may be required to accomplish this step.
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Vermont Yankee PSTG page 7 I
"5 CAUTION #25 A rapid increase in injection into the RPV may induce a large power excursion and 1 rMit in substantial core damage. j CAUTION #26 lLarge reactor power oscillations may be observed while executina this step. l CAUTION #27 Do not open MSIVs if a valid high radiation or line break condition has caused the {
isolation.
CAUTION #28 lDo not vent via SGTS if Drywell pressure is creater than 7 psia. I CAUTION #30 I initiate Torus Cooling if HPCI, RCIC, or SRVs are in use provided RHR Subsystem is j not required for: j
- Core Cooling )
- Drywell/ Torus Sprays.
1 CAUTION #31 I i j Control Room indication of the following parametsrs are subject to instrument {
error: .
- DRYWELLTEMPERATURE i10'F 1
-REACTOR PRESSURE t 40 psi 3
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Vennont Yankee PSTG page 8 RPV CONTROL GUIDELINE g.
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.4 PURPOSE The purpose of this guideline is to:
o Maintain adequate core cooling, o Shut down the reactor, and o Cool down the RPV to cold shutdown conditions (RPV water temperature <
212* F).
ENTRY CONDITIONS The entry conditions for this guideline are any of the following: .~ -
o RPV water level below +127 inches (Iow RPV level scram setpoint) or levak ,
cannot be determined
{ j o A condition which requires reactor scram, and reactor power above 2% (APf M -
downscale trip) or cannot be determined j 3
OPERATOR ACTIONS R C-l If reactor scram has not been initiated, initiate reactor scram.
Irrespective of the entry condition, execute [ Steps RC/L, RC/P, and RC/0) concurrently.
- 1 RC/L Monitor and control RPV water level.
R C / L-I Confirm initiation
- any of tha following:
_. o isolation
. o ECCS o Emergency diesel generators initiate any of these which should have initiated but did not.
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.c Vermont Yankee PSTG page 9
$34 if while executing the following step:
o RPV water level cannot be determined, RPV FLOODING IS REQUIRED; enter
%' [ procedure developed from CONTINGENCY #6].
o RPV Flooding is required, enter [ procedure developed from CONTINGENCY
- 6].
R C/ L-2 Restore and maintain RPV water level between +127 irches and +177 inches with one or more of the following systems: _
E E
o Condensate /feedwater o CFD o RCIC o HPCI' I
o Core Spray ,
i q o LPCI If RPV water level cannot be restored and maintained above 127 inches, maintain RPV water level above TAF.
If RPV water level can be maintained above TAF and the ADS timer has initiated, prevent automatic RPV depressurization by reseting the ADS timer (s).
If RPV water level cannot be maintained above TAF, enter [ procedure developed from CONTINGENCY #11 lif Altemate Shutdown Coolina is required, enter ON 3156. I R C/Le3 Proceed to cold shutdown in accordance with OP 0109.
,i-t
_ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ . _ _ _ _ _ _ _ _ _ . _ _ _ _ __.-_____...h_.___ ._m ___ _ _ _ _ _b._ _ . _ _ _ . _ _ _ _ _ _ _ _ _ _
VCrmont Yankee PSTG page 10 t RC/P Monitor and control RPV nrassure.
If while executing the following steps:
o Emergency RPV Depressurization is anticipated, rapidly depressurize the RPV with the main turbine bypass valves..
b o Emergency RPV Depressurizatiort or RPV Flooding is required and less than 4 SRVs (number of SRVs dedicated to ADS) are open, enter (procedure developed from CONTINGENCY #2].
o RPV Flooding is required and at least 4 SRVs are open, enter [ procedure developed from CONTINGENCY #6].
RC/P-1 If any SRV is cycling, manLally open that SRV until RPV pressure drops to 950 psig (RPV pressure at which all turbine bypass valves are fully open).
a.
1 If while executing the following steps: i o Suppression pool temperature cannot be maintained below the Heat j Capacity Temperature Limit, maintain RPV pressure below the Limit.
HEAT cAPActrYTEMPERATURE UMT E ris 300 F14 250 E i s 2=
s f:
y 1s0
[ %-
1 :
I 100' l
0' 0 200 400 600 800 1000 1200 RPV Pressure (peng) o Suppression Pool water level cannot be maintained below the Suppression Pool Load Umit, maintain RPV pressure below the Limit.
)
u ,
o -
)
Vermont Yattee PSTG page 11 g
SuPPRESSON POOL LOAD LNir as as E
24
\
\
] ". ( -
I ": \
18 14 T '
12
\
10
\ ,
0 200 400 600 800 1000 1200 g RPV Pressure (poig) .,,,
o Steam Cooling is required, enter [ procedure developed from CONTINGE84CY ,
2
- 31. -
-) .
If while executing the following steps:
o The main condenser is available, and o There has been no indication of gross fuel failure or steam line break, open MSIVs to re-establish the main condenser as a heat sink.
- 27 R C/P-2 Control RPV pressu;e below 1055 psig (high RPV pressure scram setpoint) with the main turbine bypass valves.
RPV pressure control may be augmented by one or more of the following
. systems:
y;- - #12 !
o HPCI o RCC l#15 e 3RVs only when suppression pool water level is above 6 feet.
o RWCU if no boron has been injected into the RPV. ;
o Steam line drains t- R 1_ ____ _ a
Vermont Yankee PSTG page 12 o RWCU (let-down mode) if no boron has been injected into the RPV.
. +
4 If while executing the following steps the reactor is not shutdown, return to
[ Step RC/P-21.
RC/P-3 When either:
o All control rods are inserted beyond position 02 (maximum subcritical -
banked withdrawal position), or o 511 pounds (Co'.d Shutdown Boron Weight) of boron has been injected into the RPV, or depressurize the RPV and maintain cooldown rate below 100*F/hr (RPV cooldown rate LCO). __,
- 14 E
R C / P-4 When the RHR shutdown cooling interlocks clear, initiate the shutdown ' j ["
cooling mode of RHR.
i If RPV cooldown is required but cannot be accomplished and all control rods are inserted beyond position 02 (maximum subcritical banked withdrawal position), ALTERNATE SHUTDOWN COOLING IS REOUIRED: enter ON 3156 R C/ P- 5 Proceed to cold shutdown in accordance with OP 0109.
RC/O Monitor and enntrol raneter power.
If while executing the following steps:
o All control rods are inserted beyond position 02 (maximum subcritical banked withdrawal position), terminate boron injection and enter OE 3100 (scram procedure).
R C / Q'-1 Confirm or place the reactor mode switch in SHUTDOWN or REFUEL when main steamline flow is < 0.5 Mlbs/hr per steamline.
RC/Q-2 Confirm or initiate recirculation flow runback to minimum.
_ _ _ _ _ _ _ _ _ _ _ _ _ _ _ . _ _ _ _ _ ____________m____________ s
Vermont Yankee PSTG pape 13 RC/O 3 If reactor power is above 2% (APRM downscale trip) or cannot be E determined:
c.
- y" o trip the recirculation pumps o manually initiate ARl/RPT l Execute [ Steps RC/O-4 and RC/O-51 concurrently. l-RC/Q-4 if the reactor cannot be shutdown before suppression pool temperature reaches 110*F (Boron injection initiation Temperature), BORON INJECTION IS REQUIRED; inject boron into the RPV with SLC and inhibit automatic initiation of ADS.
If boron cannot be injected with SLC, inject boron into the RPV by one or more of the following alternate methods:
o Local firing of Squib valve o RWCU -
o CFD R C / Q -4.1 if boron is not being injected into the RPV by RWCU, conikm automatic isolation of or manually isolate RWCU.
R C / Q -4.2 Continue to inject boron until 511 pounds (Cold Shutdown Boron Weight) of boron have been injected into the RPV.
R C/Q-4.3 Enter OE 3100 (scram procedure).
4
_ .__u-__________. - _ _ ___ ___.-_m .k _
Vermont Yankee PSTG page 14 RC/Q-5 Inser1 control rods as follows:
R C / Q -5.1 If any scram valve is not open:
o De-energize the scram solenoids (ie: remove the fuses which de-energize RPS scram solenoids).
o isolate end vent the scram air header, if all control rods are not inserted to or beyond position 02, continue in this guideline at [ Step RC/O-5.2].
o Terminate boron injection and enter OE 3100 (scram procedure).
RC/Q 5.2 Reset the reactor scram.
RC/Q 5.3 If the reactor scram cannot be reset:
- 1. Start all CRD pumps.
If no CRD pump can be started, continue in tnis guideline at
[ Step RC/Q-5.E.1]. '
g
if at anytime the scram can be reset, open CRD-56 and reset the scram.
- 3. Bypass the Rod Worth Minimizer
- 4. Rapidly insert control rods manually until the reactor scram can be reset.
- 5. If all control rods are not inserted to or beyond position 02, continue in this guideline at [ Step RC/O-5.6.1].
RC/Q 5.3 If the scram can be reset:
- 1. Verify /open the SDV vent and drain valves.
7-
- 2. Insert a manual scram signal.
R C / Q - 5.3.1 If inward rod motion was observed:
- 1. If all rods are not inserted to or beyond position 02, continue in this guideline at
[ Step RC/Q-5.2]. !
- 2. If all rods are inserted to or beyond position 02, terminate boron injection and enter OE 3100 (scram procedure).
e
_ _ _ _ - - - _ - - _ _ _ - - - _ _ _ _ _ _ . _ _ __ _n-- -_n 1
l Vermont Yankee PSTG page 15 R C /Q-5.3.2 If inward rod motion was not observed:
- 1. Reset the scram.
- 2. Verify /open the SDV vent and drain valves and continue in this guideline at
[ Step RC/Q-5.4].
R C / Q-5.4 Individually open the scram test switches for control rods not inserted beyond position 02 (ma.x! mum suberitical banked withdrawal position).
- 1. If all rods are inserted to or beyond position 02, terminate ,
boron injection and enter OE 3100 (scram procedure).
2 If all rods are not inserted to or beyond position 02, continue in this guideline at (Step RC/O-5.5].
RC/Q-5.5 Reset the reactor scram.
R C / Q - 5. 5.1 If the reactor scram cannot be reset:
e
- 1. Continue in this guideline at [ Step l RC/Q 5.3]. ,
RC/Q-5.5.2 If the reactor scram can be reset: ,
- 1. Bypass the RWM.
- 2. Manually insert control rods not inserted to or beyond position 02.
- 3. If all rods are inserted to or beyond position 02, terminate boron injection and enter OE 3100 (scram procedure).
4 If all rods are not inserted to or beyond position 02, continue in this guideline at
[ Step RC/Q 5.3].
RC/Q-5.6 If any control rod cannot be inserted beyond position 02:
I 1. Individually direct the effluent from the withdraw line I vent to a contained radwaste drain for each control rod not inserted beyond position 02.
- 2. When all control rods are inserted to or beyond position 02, terminate boron injection and enter OE 3100 (scram procedure).
- -_- - - - - - - - - . - _ _ m
Vermont Yankee PSTG page 16 l
4y SUPPRESSION POOL CONTROL GUIDELINE i
PURPOSE The purpose of this guideline is to: ;
o Maintain primary containment integrity, and o Protect equipment in the primary containment.
ENTRY CONDITIONS The entry conditions for this guideline are any of tlee following:
o Suppression pool temperature r%ve 100*F (most limiting suppression pool temperature LCO) ;
5 o Suppression pool water volume above 70,000 cu. ft. (maximum suppression -
pool water volume LCO) o Suppression pool water volume below 68,000 cu. ft. (minimum suppression pool water volume LCO)
OPERATOR ACTIONS Irrespective of the entry condition, execute [ Steps SP/T and SP/L]
concurrently.
S P/T Monitor and control sunoression cool temperature.
- 1 S P /T-1 When suppression pool temperature exceeds 100*F (most limiting suppression pool temperature LCO), operate available suppression pool cooling.
l sis S P/T;2 Before suppression pool temperature reaches 110*F (Boron injection Initiation Temperature):
- 1. Runback recirculation flow to minimum.
- 2. Transfer electrical loads to the Startup Transformers.
- 3. Manually scram the reactor; enter OE 3100 (scram procedure) and execute it concurrently with this procedure.
S P /T-3 If suppression pool temperature is above 120*F (T.S. suppression pool temperature LCO) and the RPV is isolated from the main condenser, commence depressurizing the RPV at normal cooldown rates to < 200 psig.
1
,_ a -
Vermont Yarkee PSTG _
page 17 S P/T-4 if suppression pool temperature cannot be maintained below the Heat Capacity c Temperature Limit, maintain RPV pressure below the Limit. _
ll #a s .. -
- #13
-i
- 14 HEAT CAPACfTY TEh4'ERATUFE UMIT m ,
c1 -
250 - -
C .
e N
['50 w -
,_ i I 100 ,
E h l 50 : 1 0
0 200 400 600 800 1000 1200 RPV Pressure (pelg)
If suppression pool temperature and RPV pressure cannot be restored and 1 maintained below the Heat Capacity Temperature Umit, EMERGENCY RPV j DEPRESSURIZATION IS REQUIRED: 1
- 1. Enter [ Procedure developed from Contingency #2] and execute it ;
concurrently with this procedure. ;
- 2. Enter [ Procedure developed from the RPV Control Guideline) at [ Step J RC/P-3].
SP/L Monitor and control numereenlon noel water volumellevel.
- 1 S P / Lil Maintain suppression pool water volume between 70,000 cu. ft. (maximum
~
suppression pool water volume LCO) and 68,000 cu. ft. (minimum suppression pool water volume LCO).
--__.___w- _______-_ _ _ _ , . , _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _
Vermont Yankee PSTG page 18 DW/ Torus AP vs. Indicated Water Level P.
11.3 g
+ . 70,000 cu.ft E 11.2 I 11.1 i
f '
g
- 68,000 cu.ft 4 11.0 3
10.9 '
- /
e" 10.8 0.0 0.5 1.0 1.5 2.0 2.5 DryweWTorus AP (psid) l I
If suppression pool water volume cannot be maintained above 68,000 cuf;ft.
(minimum suppression pool water volume LCO) execute [ Step SP/L-2]. '
If suppression pool water volume cannot be maintained below 70,000 cu. ft.
(maximum suppression pool water volume LCO), execute [ Step SP/L-3].
W
_ _ _ _ _ _ . _ _ _ _ _ _ _ _ _ . _ . _ _ _ ___ _ _ . _ _ . . _ _Q . _ . _ _ .O ** 6
J Vermont Yankee PSTG page 19 1
S P / Lr 2 SUPPRESSION POOL WATER VOLUME BELOW 68,000 cu. ft. (minimum
@ suppression pool water volume LCO) y Maintain suppression pool water level above the Heat Capacity Level Limit using any of the following systems: _
o Core Spray o RHRSW HEAT CAPACITY LEVEL LIMIT 12 10 k l E w
]*
g s
^
N 4 a f. t a 4 2
0 o 10 20 30 40 50 60 70 AT (*F)
Where ATHC - Heat Capacity Temperature Limit minus suppression pool temperature S P / L-2.1 If suppression pool water level cannot be maintained above the Heat Capacity Level Umit, EMERGENCY RPV DEPRESSURIZATION IS REQUIRED: i l
- 1. Runback recirculation flow to minimum. l
- 2. Transfer electrical loads to the Startup Transformers. l
- 3. Manually scram the reactor; enter OE 3100 (scram procedure) and execute it concurrently with this procedure.
- 4. Enter [ procedure developed from Contingency #2] and execute it concurrently with this procedure. l S P /L-2.2 If suppression pool water level cannot be maintained above 8.6 ft. (RCIC turbine exhaust):
)
- 1. Runback recirculation flow to minimum.
- 2. Transfer electrical loads to the Startup Transformers.
I
- _ _ - __-____________ _ _ . _ _ _s n - r
i Vermont Yankee PSTG page 20 l
l 3. Manually scram the reactor; enter OE 3100 (scram
- procedure) and execute it concurrently with this procedure.
- 4. Initiate suppression pool sprays.
S P/L-2.3 If suppression pool water level cannot be maintained above 6.5 ft. (highest elevation of ECCS suction within suppression pool) or the combination of suppression chamber airspace pressure and suppression pool water level cannot be maintained above the Required NPSH Curve, then line-up for injection those systems 1 which take a suction external to the primary containment. {
f REQUIRED NPSH CURVE l 80
/
- f
{ 80 !
e /
I.
L M / .
l i"
e r
/ i i
20
) 7 a
g 10 e 3 '
O 100 150 200 250 300 350 400 Torus Water Temperature (V) i l
l l
- _ _ _ _ _ _ _ _ _ __ - __ i
Vermont Yankee PSTG page 21 S P / L 3 SUPPRESSION POOL WATER VOLUME ABOVE 70,000 cu. ft. (maximum
. suppression pool water volume LCO) i S P /L-3.1 Maintain suppression pool water level below the Suppression Pool Load Limit using any of the following systems:
o RM o HPCI o RCIC If suppression pool water level cannot be maintained below the Suppression Pool Load Limit, maintain RPV pressure below the Limit.
- 13 nums:
- 14 musum.
- 31 SUPPRESSION POOL LOAD UMT ,
30 28 \ #
7 t
26 E
\
, n b '
i"- \
i
\
14 12
\
10 0 200 400 600 800 1000 1200 RPV Pressure (poig)
If suppression pool water level and RPV Pressure cannot be restored and maintained below the Suppression Pool Load Limit, EMERGENCY RPV DEPRESSURIZATION IS REQUIRED:
- 1. Runback recirculation flow to minimum.
- 2. Transfer electrical loads to the Startup Transformers.
- 3. Manually scram the reactor; enter OE 3100 (scram procedure) and execute it concurrent!y with this procedure.
- 4. Enter (procedure developed from Contingency #2) and execute it concurrently with this procedure.
l APPENDIX G JUSTIFICATION of DEVIATIONS, DELETIONS, and ADDITIONS (JDDA)
I i
4
, i
Virmont Yrnkee PSTG page 22 l
if suppression pool water level and RPV pressure cannot be maintained below the Suppression Pool Load Limit but only if adequate core cooling is assurod, terminate injection into the ;
RPV from sources external to the primary containment except '
from boron injection systems and CRD.
S P/L-3.2 When suppression pool water level reaches 22.4 ft. (elevation difference between the bottom of the suppression chamber and wetwell-to-drywell vacuum breakers' vent line) but only if suppression chamber temperature and drywell pressure are below the Drywell Spray initiation Pressure Limit:
- 18 mmmmm:
- 22
- 1. Shutdown recirculation pumps and drywell RRUs.
- 2. If suppression pool water level exceeds 22.4 ft., continue to operate drywell sprays. I DRYWELL SPRAY INITIATION PRESSURE LtMIT 360 ,
~
310 F /
j 260 g
/
g 210 ,
e 160 4
$ l S 110 ,
J e0 0 25 50 75 100 125 150 Torus Airspa Pressure (psig)
If drywell sprays are operating, continue to operate them while torus water level is > 22.4 ft.
When primary containment water level reaches 90 ft.
(Maximum Primary Containment Water Level Limit), !
terminate injection into the RPV from sources external to the !
primary containment irrespective of whether adequate core cooling is assured.
_ _ - _ _ _ - _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _A _ _ _ _ _ l.
page 23 V:rmont Yankte PSTG 1
DRYWELL CONTRCL GUIDELINE PURPOSE The purpose of this guideline is to:
o Maintain primary containment integrity, and o Protect equipment in the primary containment.
ENTRY CONDITIONS The entry conditions for this guideline are any of the following:
o Drywell temperature above 160'F (drywell maximum normal operating temperature assumed for EO analysis) o Utywell pressure above 2.5 psig (high drywell pressure scram setpoint)
OPERATOR ACTIONS Irrespective of the entry condition, execute [ Steps DW/T and PC/P]
. concurrently.
DW/T Monitor and control drvwell temperature.
- 1 DW/T l When drywell atmospheric temperature exceeds 160*F (drywell maximum normal operating temperature assumed for EQ analysis), operate available drywell cooling.
- 6 l Execute (Steps DW/T-2 and DW/T-31 concurrently. l D W/T-2 If drywell temperature [near the cold reference leg instrument vertical runs] reaches t;A RPV Saturation Temperature, RPV FLOODING IS REQUIRED:
- 1. Runback recirculation flow to minimum.
- 2. Transfer electrical loads to the Startup Transformers.
- 3. Manually scram the reactor; enter OE 3100 (scram procedure) and execute it concurrently with this procedure.
- 4. Enter [ procedure developed from Contingency #2] and execute it concurrently with this procedure.
l 0
v ermont Yankee PSTG
~ pags 24 RPV SATURATION CURVE 66 '
3 :' I , , -
510 '.
1 /
32 d , 460 g
/
N8 -
/
$% 410 /
c re
/
!. .s2! 3So r.
g 310
)
260 4 d 210 0 200 400 600 800 1000 1200 RPV Pressure (psig)
DW/T-3 If drywell temperature cannot be stabilized below 280'F (drywell design temperature) manually scram the reactor; enter OE 3100 (scram procedure) and execute it concurrently with this procedure.
- 31 DW/T-4 If drywell temperature cannot be stabilized below 280'F (drywell design temperature) but only if suppression chamber airspace temperature and pressure are below the Drywell Spray Initiation Pressure Limit:
- 18
- 23
- 1. Shutdow:' recirculation pumps and drywell RRUs.
- 2. Spray the drywell with either of the following systems:
o RHR o Fire System
i V;rmont Yankee PSTG pag 2 25 DRYWELL SPRAT .NITIATON PRESSURE LIMIT 8" p 310
/
5 2=
1 ,
1 f 210 - ='
/
180
- /
,5 110 6G 0
l 25 50 75 100 150 125 Torus Airspace Pressure (pseg)
When drywell sprays are no longer required to maintain drywell temperature below 280'F, terminate spraying and restore the RRUs.
If drywell temperature cannot be msintained below 280'F (drywell design temperature), EMERGENCY RPV DEPRESSURIZATION IS REQUIRED; enter (procedure developed from Contingency #2] and execute it concurrently with this procedure.
PC/P Monitor and control crimary containment oressure,
- 1 P C / P-1 If drywell pressure is > 2.5 psig, attempt to reduce drywell pressure with the following:
- 28
- 31 o Drywell RRUs o SBGT , only when the temperature in the space being evacuated is below 212'F (Maximum Noncondensible Evacuation Temperature).
- 22 P C/P-2 If drywell pressure is > 2.5 psig, but only if suppression pool water level is below 25 ft. (elevation of suppression pool spray nozzles), initiate suppression pool sprays and maintain suppression chamber airspace s f
Vumont Yankee PSTG pag 2 26 pressure below 19 psig (Suppression Chamber Spray Initiation Pressure) using the following systems:
- 8
-i
- 18 o RHR o Fire System P C/P-3 If suppression chamber pressure exceeds 19 psig (Suppression Chamber Spray Initiation Press Jre) but only if suppression chamber airspace temperature and pressure are below the Drywell Spray initiation Pressure Limit:
- 18 M1
- 22 I summi l
- 23
- 1. Shutdown recirculation pumps and drywell RRUs. !
- 2. Isolate SGTS before spraying.
- 3. Spray the drywell using the following systems: ,
o RHR 4 o Fire System
{
DRYWELL SPRAY INITIATION PRESSURE LIMIT i
360 310 '
s' /
I 2a / I i
g 210 ,
/
160 '
R '
[
E f g 110 f
60 0 25 1 75 100 125 150 Torus Asspace Fhessure (psig)
% l.
Vermont Yankts PSTG Paga 27 P C/ P-4 Ifsuppression chamber pressure cannot be maintained below the Pressure Suppression Pressure, EMERGENCY RPV DEPRESSURlZATION IS REQUIRED; enter (procedure developed from Contingency #2] and execute it concurrently with this procedure.
PRESSURE SUPPRESSION PRESSURE 70 60 '
5 .
$ 50 [
i *
[ ~
j
$ 30 20 ,
a
- 10 ' (
0' O 5 10 15 20 25 30 Torus Water Level (ft)
P C/P-5 If suppression chamber pressure cannot be maintained below the Primary Containment Pressure Limit, RPV FLOODING IS REQUIRED; enter (procedure developed from Contingency #6) and execute it concurrently with this procedure.
PRIMARY CONTAINMENT PRESSURE UMIT 70 65 3 A l ", N
! N-g s5 e 50 45 a
j 40 0
35 30 >
0 5 to 15 20 25 30 Torus Level (f0
_ _ _ _ _ _ _ _ _ _ _ _ _ . _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ .._._______._____.____3_____._____________.________________ __ . _ . _ _ _ _ _ _
___I___._____.__._.___________.__________________j
~
V rmont Ytnk$2 PSTG pag 2 28 P C/P-6 If suppression chamber pressure cannot be maintained below the Primary Containment Pressure Umit after the RPV.has been flooded, but only if suppression chamber airspace temperature and pressure are below the Drywell Spray Initiation Pressure Limit, then irrespective of whether i
adequate core cooling is assured:
- 22 Ml
- 23
- 1. Shutdown recirculation pumps and drywell RRUs.
- 2. Isolate SGTS before spraying.
- 3. Spray the drywell using the following:
o RHR o Fire System
- 4. If suppression pool water level is below 25 ft. (elevation of suppression-pool spray nozzles), initiate suppression pool sprays.
DRYWELL SPRAY INITIATION PRESSURE LIMIT 360 310 ,
/
e a= . -
a f 210
. 8 f 160 4
E M 110 0
/ 25 50 75 100 125 150 Torus Airspace Pressure (psig)
P C/P-7 If suppression chamber pressure exceeds the Primary Containment Pressure Limit, vent the primary containment in accordance with OP 2125 (procedure for containment venting] to reduce and maintain pressure below the Primary Containment Pressure Limit.
- 22 l
__._________m_____ __ __________ __
Varmon! Yankee PSTG pags 29 !
l SECONDARY CONTAINMENT CONTROL GUIDELINE l
PURPOSE The purpose of this guideline is to:
o Protect equipment in the secondary containment, o Limit radioactivity release to the secondary containment, and either:
o Maintain secondary containment integrity, or o Limit radioactivity release from the secondary containment.
ENTRY CONDITIONS The entry conditions fo this guideline are any of the following secondary containment conditions:
o An area temperature above the maximum normal operating temperature o A Rx Bldg. HVAC exhaust radiation level above 14 mR/hr (secondary containment HVAC isolation setpoint) o An area radiation level above the maximum normal operating radiation level o Continuous floor drain sump pump operation o An unexpected area water level above the maximum normal operating water level OPERATOR ACTIONS If while executing the following steps secondary containment HVAC exhaust radiation level exceeds 14 mr/hr :
o Confirm or initiate isolation of secondary containment, and o Confirm initiation of or manually initiate SBGT.
i t f
' Wrmont Ytnkee PSTG pag 9 30 i:
If while executing the following steps:
o Secondary containment HVAC isolates, and, o Secondary containment HVAC exhaust radiation level is below 14 mr/hr ,
L restart secondary containment HVAC, defeating high drywell pressure and low '
RPV water level isolation interlocks if necessary.
Iml !
Irrespective of the entry condition, execute [ Steps SC/T, SC/R, and SC/L]
concurrently.
SC/T Monitor and control secondary containment temoerate.
S C/T-l Operate available RRUs.
S C/T-2 If secondary containment HVAC exhaust radiation levelis below 14 mr/hr, operate available secondary containment HVAC.
S C /T-3 If an area temperature exceeds its maximum normal operating temperature, isolate all systems that are discharging into the area except systems necessary to shutdown the reactor, assure adequate core cooling, or suppress a fire.
S C /T-4 If a primary system is discharging into secondary containment, then before any area temperature reaches its maximum safe operating
- temperature:
- 1. Runback Recirc flow to minimum.
- 2. Transfer electrical loads to the Startup Transformers.
- 3. Manually Scram the reactor; enter OE 3100 [ scram procedure) and execute it concurrently with this procedure.
SC/T-5 If a primary system is discharging into secondary containment, then when the maximum safe operating temperature for a limiting combination is exceeded, EMERGENCY RPV DEPRESSURl2ATION IS REQUIRED.
S C/T-6 Establish RPV shutdown cooling once conditions permit..
1 x I
Vermont Yanke@ PSTG page 31 MAX NORMAL OPERATNG TEMPERATURE MAXNUM SAFE OPERATNG TEMPERA 1LfqE UMITING AREA COMBINATION 6 oeou. LOX C/AD FILE s1 EE$E CHANNEL 8 ,, f, m r8 mm mr d
ggEmF F Pmrrr E. E. E. I. g f" h h ma a m 3 E Egg(( E it ks tu. u s.,,k. s i N. s M k. 5 -5g " I. I. $.
m 2 (Mu NO.AL TEMP) i i I e I (MAX SAFE TEMP i i
..' u'. ..
' .. u'.
I II IE 1 E
i
- 8 i
0~I 88 88 i t 8
1
$$i I
U 25 104 NE CORNER RM 21F 194 0 O O O O O O O O 23 104 NE CORNER RM . 232' 194 O O O O O O O O O 26 104 SE CORNER RM . 217 194 O O O O O O O O O 24 104 SE CORNEA RM 232 194 O O O O O O O O si 104 torus RM .NE W O O O O O O O O O 22 104 torus RM sE 250 0 0 0 0 0 0<0 0 0 is 104 TORusRM sw W O 3 0 0 11 118 TORUS RM . NW 318 O O O
- io4 EL 2sr . NE E O O O O O O O O O O J O O 104 EL 257 - NW 243 O O O O 104 EL 257 - Sw W G O O O O O O O O O O O 104 EL 252 EAST 1eo O .J 0 0 0 ,
27 its~ PERS ACC LOCM AREA 250 0 0 0 0 0 0 0 0 0 0 0 0 0 as 104 EL 20Cr NE E O O O O O O O O O O O O O O 104 EL 20Cr . NW 16o O O O O O O O O O O O O O O O O 104 EL 2ecr - sw too O O O O O O O O O O O i
l 2a 104 EL aso' . sE 1se O O O O O O O O O O O O O O O O ils AaOve RCU PUMPS Y O O O O l 104 EL 303' EAST 16o O O O O O O O ts2 ,
A urating Coren non .4.t wher. . act inis l No i rr,.reur. inowinior exisi .
l' at th. Inters.ctions of th. Indic.ted rees.
I 1
)
1 V;rmont Yankee PSTG pag 2 32 l
SC/R Monitor and control secondarv containment radiation levels.
S C/ R-l if an area radiation level exceeds its maximum normal operating j radiation level, isolate all systems that are discharging into the area '
except systems required to shut down the reactor, assure adequate core cooling, or suppress a fire.
SC/R-2 If a primo , system is discharging into secondary containment, then before any area radiation level reaches its maximum safe operating radiation level:
- 1. Runback Recirc flow to minimum.
- 2. Transfer electrical loads to the Startup Transformers.
- 3. Manually Scram the reactor; enter OE 3100 [ scram procedure] and execute it concurrently with this procedure.
Rx BLDG AREA RADIATION LEVEL
( mR/hr )
MAX NORMAL
- MAX SAFE "
STA# LOCATION OPERATING VALUE OPERATING VALUE 1 SUPP CHAMBER CATWALK 70 700 2 NORTH PERS. ACCESS 40 400 3 south RR ACCESS 3 30 4 TIP ROOM 60 600 6 ELEVATOR ENT. 280 50 500 7 CRD REPAIR ROOM 220 2200 8 ELEVATOR ENT. - 303' 150 1500 10 ELEVATOR ENT. - 318' 50 500 12 ELEVATOR ENT. - 348' 80 800
- The Max Normal Operating Value = 10 X normal operating value
" The Max safe Operating Value = 100 X normal operating value
\
_ _ _ _ _ _ _ _ . _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ h.
V:rmont Yankee PSTG pag 2 33 iC/L Monitor and control secondary containment water levels.
S C/ L-l if an area water level is above its maximum normal operating water level, operate available sump pumps to restore and maintain it below its maximum normal operating water level.
If any area water level cannot be restored and maintained below its maximum normal operating water level, isolate all systems that are discharging water into the sump or area except systems required to shut down the reactor, assure adequate core cooling, or suppress a fire.
S C / L-2 If a primary system is discharging into secondary containment, then before any area water level reaches its maximum safe operating water level:
- 1. Runback Recirc flow to minimum.
- 2. Transfer electrical loads to the Startup Transformers.
- 3. Manually Scram the reactor; enter OE 3100 (scram procedure) and execute it concurrently with this procedure.
S C/ L-3 If the maximum safe operating water level is exceeded in more than one area. EMERGENCY RPV DEPRESSURIZATION IS REQUIRED.
S C / L-4 Establish RPV shutdown cooling once conditions permit.
Rx BLDG AREA WATER LEVELS
( inches above noor )
MAX NORMAL MAX SAFE LOCATION OPERATING LEVEL OPERATfNG LEVEL RCic RCCi' <1 12 HPCI Room <1 12 NE CORNER ROOM <1 12 SE CORNER ROOM <1 12 Torus ROOM <1 12 a n
Virmont Yankes PSTG pag 2 34 CONTINGENCIES l
l 1
l l
e ,
Vermont Yankee PSTG page 35 CONTINGENCY #1: Level Restoration if while executing the following steps RPV water level cannot be determined, RPV FLOODING IS REQUIRED enter [ procedure developed from Contingency
- 61.
If while executing the following steps RPV water level cannot be maintained above 127 in. (ADS initiation setpoint), prevent automatic initiation of ADS by either resetting the ADS timers or by placing them in the AUTO INHIBIT position.
C1-1 Line up for injection and start pumps in 2 or more of the following injection subsystems:
o Condensate o LPCIA o LPCIB o Core Spray-A o Core Spray-B Enter [ Procedure developed from CONTINGENCY #2].
C1-2 If less than 2 of the injection subsystems can be lined up with pumps running, but at least one Core Spray subsystem can be lined up with suction form the suppression pool and the pump is running, SPRAY COOLING IS REQUIRED; enter [ Procedure developed from CONTINGENCY #4].
C1-3 Line up for injection and start pumps in 2 or more of the fo!!owing alternate injection subsystems as possible:
o RHR service water o Fire system o Condensate Transfer system o SLC (test tank) o SLC (boron tank)
Enter [ Procedure developed from CONTINGENCY #2].
C1-4 If no system, injection subsystem or alternate injection subsystem !s lined up with at least one pump running, STEAM COOLING IS REQUIRED; enter
[ Procedure developed from CONTINGENCY # 3] and execute it concurrently with this procedure.
C1-5 When any system, injection subsystem or alternate injection subsystem is lined up with at least one pump running, enter [ Procedure developed from CONTINGENCY #2].
1 I
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vennant vanu s esta paga se I
i
_ _ _ _ _ _ - - _ - - - - _ - - - - s i
_ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ - _ - - _ _ _ _ = _ _ _ _ _ _ - _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ ____ _
V;rmont Yankee PSTG pag 2 37 1
CONTINGENCY #2: Emeraency RPV Depressurization C2-1 If all control rods are inserted to or beyond position 02 (maximum suberitical banked rod withdrawal position):
- 13
- 14
- 22 C 2 - 1.1 If the MSIVs are open and the main condenser is available:
o Open a minimum of 5 turbine bypass valves.
C 2 - 1. 2 If less than 5 (Minimum Number of Turbine Bypass Valves Required for Emergency Depressurization) Bypass valves are open procede to [ Step C2-2.1].
C2-2 If all control rods are not inserted to or beyond position 02 (maximum subcritical banked rod withdrawal position), terminate and prevent all injection into the RPV except boron and CRD.
- 13 mum
- 14 C 2 - 2.1 If suppression pool water level is above 6 ft. (elevation of top of SRV discharge device):
o Open all SRVs.
C 2-2. 2 If less than 3 (Minimum Number of SRVs Required for Emergency Depressurization) SRVs are open and RPV pressure is at least 50 psig (Minimum SRV Re-opening Pressure) above suppression chamber pressure, rapidly depressurize the RPV using one or more of the following systems:
- 22 o Bypass valves o Main steam line drains o HPCI steam line o RCIC steam line o RPV Head vent if RPV Flooding is required, enter (procedure developed from CONTINGENCY
- 61 C 2-3 Enter (procedure developed from the RPV Control Guideline] at [ Step RC/P-4].
_______ _ _ _ _ _ _ _____~____ _ _ _ _ _ _ _ _ _. _ _ _ _____ n __. . _ _ _ _ _ . a
Vzrmont Y:nkee PSTG paga 38 CONTINGENCY #3: Steam Cooling If while executing the following steps Emergency RPV Depressurization is required or any system, injection subsystem, or alternate injection subsystem is lined up for injection with at least one pump running, enter
[ Procedure developed from CONTINGENCY #21 C3-1 When RPV water level drops to -87 in. (Minimum Zero-Injection RPV Water Level) or if RPV water level cannot be determined, open one SRV.
If RPV pressure drops to 700 psig (Minimum Single SRV Steam Cooling Pressure), enter [ procedure developed from CONTINGENCY #21 L1
Vermont YCnkee PSTG page 39 CONTINGENCY #4: Core Coolina Without Level Restoration C4-1 If at least one core spray subsystem is lined-up with suction from the suppression pool and a pump running, perform EMERGENCY RPV DEPRESSURIZATION; enter (procedure developed from Contingency #2] and execute it concurrently with this procedure.
- 13 C4-2 Operate Core Spray subsystem (s) with suction from the suppression pool.
When RPV pressure is below 120 psig (RPV pressure for rated Core Spray flow), terminate injection into the RPV from sources external to the primary containment except for borc.: injection and CRD.
- 31 C4-3 When RPV water level is restored to TAF, enter (procedure developed from the RPV Control Guideline) at [ Step RC/L].
l
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Virmont YLnkee PSTG paga 40 CONTINGENCY #5: Alternate Shutdown Coolina C5-1 Initiate suppression pool cooling.
C5-2 Close the RPV head vents,MSIVs, main steam line drain valves, and HPCI and RCIC isolation valves.
C 5-3 Place the control switch for one (Minimum Number of SRVs Required for Alternate Shutdown Cooling) SRV in the OPEN position.
C5-4 Slowly raise RPV water level to establish a flow path through the open SRV back to the suppression pool.
l C5-5 Start one Core Spray or LPCI pump with suction from the suppression pool.
C5-6 Slowly increase Core Spray or LPCI Injection into the RPV to the maximum.
C 5 - 6.1 If RPV pressure does not stabilize at least 50 psig (Minimum Alternate Shutdown Cooling RPV Pressure) above suppression chamber pressure, start another Core Spray or LPCI pump.
C 5 - 6. 2 If RPV pressure does not stabilize below 230 psig (Maximum Altemate Shutdown Cooling RPV Pressure), open another SRV.
C 5 -6.3 If the cooldown rate exceeds 100*F/hr (maximum RPV cooldown rate LCO), reduce Core Spray or LPCI injection into the RPV until the cooldown rate decreases below 100'F/hr (maximum RPV cooldown rate LCO) or RPV pressure decreases to within 50 psig (Minimum SRV Re-opening Pressure) of suppression chamber pressure, whichever occurs first.
C5-7 Control suppression pool temperature to maintain RPV water temperature above 70'F (RPV head tensioning limit).
C5-8 Proceed to cold shutdown in accordance with OP 0109.
t I
V:rmont Y1Dkee PSTG pag 2 41 CONTINGENCY #6: RPV Flooding l C 6-1 If any control rod is not inserted beyond position 02 (maximum subcritical I banked withdrawal position):
C 6 - 1.1 If open, close the following valves:
o MSIVs o Main Steamline drain valves When RPV pressure falls below the Minimum Alternate Flooding Pressure, continue in this procedure.
Minimum Alternate RPV Number of open SRVs Flooding Pressure (psig) 1 412 2 200 3 130 4 94
- 31 C 6-1. 2 Commence and slowly increase injection into the RPV with the following systems:
- 25 o Feedwater pumps o Condensate pumps o CFD o RCIC o HPCI o LPCI until any one of the following conditions is satisfied:
o reactor power increases and continues to increase, or o at least one SRV can be opened and RPV pressure is above the Minimum Alternate Flooding Pressure, or o RPV level can be maintained above TAF.
_ _ _ _ _ _ _ - _ _ _ _ _ e n
Virmont Y nkee PSTG pag 2 42 If none of the above conditions are satisfied, commence and slowly increase injection into the RPV with the following systems until at least one of the above conditions is satisfied:
l#2s l o Core Spray l o RHR service water o Fire System l
C 6- 1,3 Maintain at least 1 (minimum number of SRVs for w .ch the Minimum Alternate RPV Flooding Pressure is below the lowest ,
SRV lifting pressure) SRV open and RPV pressure above the ;
Minimum Alternate RPV Flooding Pressure, but as low as ;
practicable, by throttling injection.
! If RPV level can be maintained above TAF and RPV Flooding is not required, enter [ procedure developed from RPV Control Guideline 1 at (Step RC/L-11.
C 6 - 1. 4 When all control rods are inserted to or beyond position 02 i (maximum subritical banked withdrawal rod position),
continue in this procedure.
C 6-2 If at least 3 (Minimum Number of SRVs Required for Emergency Depressurization) SRVs can be opened or if motor driven feedwater pumps are available for injectian, close the MSIVs, main steam line drain valves, HPCI, and RCIC isolation valves.
C 6-3 If RPV water level cannot be determined:
C 6-3.1 Commence and increase injection into the RPV with the following systems until at least 3 (Minimum Number of SRVs Required for Emergency Depressurlzation)) SRVs are open and RPV pressure is not decreasing and is at least 50 psig (Minimum RPV Flooding Pre sure) 2cwe suppression chamber pressure.
o Feedwater/ Condensate o Core Spray o LPCI o CFO o RHR Service Water o Fire System o Condensate Transfer o SLC (test tank) o SLC (boron tank)
C 6-3. 2 Maintain at least 3 (Minimum Number of SRVs Required for Emergency Depressurization) SRVs open and RPV pressure at g o
Vsrmont Yanka PSTG pags 43 least 50 psig (Minimum RPV Flooding Pressure above suppression chamber pressure by throttling injection. C 6-4 If RPV water level can be determined, commence and increase injection into the RPV with the following systems until RPV water level is increasing: o Feedwater/ Condensate i o Core Spray o LPCI o CRD o RHR Service Water . o Fire System i o Condensate Transfer o SLC (test tank) o SLC (boron tank) l C 6-5 If RPV water level cannot be determined: C 6 - 5.1 Continue injecting water into the RPV until drywell temperature near level instrument reference legs is below 212*F and RPV water level instrumentation is available.
#31 If while executing the following steps, RPV water level can be determined, continue in this procedure at [ Step C6-61.
C 6-5. 2 If it can be determined that the RPV is filled or if RPV pressure is at least 50 psig (Minimum RPV Flooding Pressure) above suppression chamber pressure:
#31 o determine the Maximum Acceptable Core Uncovery Time o terminate all injection into the RPV and allow RPV water level to reduce
_u_ _ _______________-__________ - -- n- _ _-_--__ - _ _ _ _ -
V:rmont 5'anke2 PSTG pag)A4 C6 5.3 If RPV water level indication is not restored within the Maximum Core Uncovery Time Limit after commencing terminaton of injection into the RPV, return to [ Step C6-3]. MAXIMUM CORE UNCOVERY TIME UMIT 40 4 x
$ 35 ' ,
I "
- /
F
- /
q 25 '
$.E20 5., 2 p 15 l /
8 10 , p , f
/
4 l ./ 0 1 10 100 1000 10000 Time After Reactor Shutdown (minutes) C6-6 When suppression chamber pressure can be maintained below the Primary Containment Pressure Limit, enter OP 0109. PRIMARY CONTAINMENT PRESSURE LIMIT 70 65 3 60 E N
! . N m 5 55 h
E 50 ' i
.E 40 l 35 -
30 0 5 10 15 20 25 30 Torus Level (ft)
. o i
V rmont Yankte PSTG page 45' S
% _E
m-__ _ _ _ _ _ . _ _ _ _ _ _ _ _ , ._ _ _ _ _ _ _ _ __ _ . - _-___ ___ ,_-.__ __ APPENDIX B OPERATKX4AL EMERGENCY PROCEDURES WRITERS' GUIDE _ _ _ __________________.____ __ m n !
Appendix B, Rev. 3 - Writers' Guid* paci 2 APPENDIX B OPERATIONAL EMERGENCY PROCEDURES WRITERS' GUIDE
1.0 INTRODUCTION
1.1 Purnose and Scoce The purpose of this writers' guide is to provide administrative and technical guidance on the preparation of Operational Emergency Procedures (OEs) flowcharts. The Writers' Guide applies to the writing of all OEs. 2.0 FLOWCHART GUIDELINES 2.1 identification Information
- a. Information Sufficiency 1 ) The procedure number and title shall appear on each flowchart.
2 ) The date of issue / revision shall appear on each official flowchart. 3 ) The identification information shall be provided on end path procedures to provide rapid identification.
- b. Information Consistency I) The location / format of identification information shall be consistent for each flow path.
2 ) Tasks and action steps must be sequenced according to technical necesn'ty. 2.2 Contents
- a. Clarity and Conciseness 1 ) Flow path actions shall be written as short, concise statements, using words that are common in ordinary conversation. i 2 ) Statements within caution and information blocks shall be clear and '
concise. 3 ) Questions in decision blocks shall be written clearly. ! 4 ) Adverbs and articles shall be used as little as possible in flow paths. ] 5 ) The use of double negatives shall be avoided. l _ _ _ _ _ _ _ _ _ _ _ _ _ _ - - - - _ - - - - - _ . -- . m i
Appendix B, R*v. 3 - Writers' Guide pace 3 i
- b. Consistency of Terminology 1 ) Terms within and among flowcharts shall be consistent.
2 ) Caution and information blocks shall contain contingency or amplifying information, as appropriate, to enhance the referenced procedure step (s). 3 ) Action blocks shall contain action instructions as specific verbs. 4 ) All decision blocks shall require a yes/no response,
- c. Complexity 1 ) The number of actions called out per action block shall be no greater than one.
2 ) The flowchart should be structured such that specific actions, concurrent actions, and other responsibilities do not exceed the capabilities of the minimum shift staffing per Vermont Yankee Technical Specifications. 3 ) Decision blocks using "and/or" logic should be avoided. ; 4 ) Numerous objects of actions appearing in an action biock shall be listed and bulleted for ease of identification.
- d. Sufficiency and Appropriateness of Information 1 ) Any graphs or tables included in action blocks shall be adequate for readability and extraction of values.
2 ) The number of times the operator is required to leave the flowchart prior to entering the end path procedure to acquire additional information should be given careful consideration and minimized whenever possible. 3 ) Units utilt?.ed in the flowcharts shall correspond to the units of the plant instrumentation from which the operator will obtain information.
- e. Cautions 1 ) All cautions which are applicable to a partialar OE shall be grouped together, set apart from the flow diagrams, but located on the procedure for which they apply.
2 ) Those which are derived from the BWROG EPG shall retain the same caution number used in the EPG. 3 ) Those which apply to a particular OE step shall be so designated by enclosing the caution number in a circle with a tail connected to the appropriate procedure step.
~ a
Appendix B, Rev. 3 - Writers' Guide paos 4 4 ) They should not contain operator actions,
- f. Graphs and Tables 1 ) Where applicable, graphs shall clearly indicate the safe and unsafe regions.
2 ) All shall be located close to the procedure step and connected to the appropriate step using dotted lines. 3 ) All must be uniquely identified by a label. 4 ) All must contain only the relevant information needed to clarify or accomplish its purpose. 5 ) All must be prepared according to standard technical graphics l practices.
- g. Equipment Response Checks I ) Steps should be used where appropriate to verify that a task or a sequence of actions has been achieved as expected.
2 ) Such checks may consist of ensuring that an action has resulted in a command signal to a piece of equipment. Preferably, the check would ensure that an action has resulted in a positive indication that the
- equipment has responded to a command.
3 ) Checks shall only be used where practical and where it would enhance the objective of the sequence of steps.
- h. Location Information 1 ) Information on the location of equipment, controls, or displays that are infrequently used, are in out-of the-way places, or otherwise difficult to find shall be provided.
- i. Rounding Off Calculated Values 1 ) During the writing of the OEs, calculated values may be rounded off to simplify performance of operator tasks.
2 ) In deciding the degree to which a value should be rounded off, the following should be considered:
. The expected operating conditions - a more serious plant condition may require a closer tolerance, for example.
+ Instrument readability - specifications in units such that no smaller than 1/2 of a division of the instrument scale is required.
4 _ _ - - - - - - - - - . - - - - . . - - _ - - - - - - _ m i
Appendix B, R*v. 3 - Writers' Guide pact 5
- The way the instrument will be used - for example, verification of an alarm, verification of an expected condition, determination that an unexpected condition exists.
- The type of instrument readout available to the operator - for e.umple, wide or narrow range, indicator or recorder (ability to dete;mine trend).
3 ) The direc'aon in which to round off the value is subject to the following guidelines:
. If the value is an upper limit,it should b9 tounded downward.
. If the value is a lower limit, it should be rounded upward.
. Irregardless of other considerations, rounding off should be in the conservative direction.
J. Formulas and Calculations The operators' use of formulas and need for calculations in the OEs shall be minimized. If such calculations cannot be avoided, then: 1 ) The calculation must be capable of solution by hand methods, 2 ) Adequate space will be provided within the body of the procedure to record any intermediate steps required in performing the calculation. 2.3 Symbol Codina
- a. Standardization 1 ) A reascnable attempt will be made to utilize flowchart symbols which are commonly used and recognized in the industry.
2 ) Those symbols shown on Figure 1 will be reserved for use per their description.
- b. Ease of Identification 1 ) Major symbol blocks (action blocks, decision blocks, caution /Information blocks, key parameter blocks) shall be readily detected and discriminable.
2 ) Symbols shall be used to direct the operator from the flowchart to another procedure. Also, they shall be adequately coded using OE procedure entry step number for ease of identification. 3 ) Symbols shall be used to aid the operator in finding the correct entry point into a flowchart (Path-to-Path symbois). Also, they shall be adequately coded for ease of identification.
- 4) Symbol coding shall be used consistently.
_ _ _ _ _ _ - _ _ _ _ _ _ _ _ _ _ _ _ _ - _ a
Appendix B, Rev. 3 Writers' Guida pacs 6 2.4 Nomenclature Punctuation
- a. Uso of logic words 1 ) Conditional statements shall be written so that the description of the condition appears first, followed by the action instructions (i.e., If....
then...).
- b. Abbreviations, Acronyms, Symbols _,
1 ) Abbreviations, acronyms and symbols shall be used with discretion and shall be those which are familiar to the operators so . hat there is no need to consult a glossary. 2 ) Abbreviations shall be used consistently within and among flowcharts. Table 1 contains a listing of common abbreviations used at Vermont Yankee.
- c. Punctuation i 1 ) Punctuation shall comply with standard American English rules and used in such a canner that it aids the user. For exampie, peness to help operatorr. :,eparate action statements, a question mark to aid in identification cf interrogative statements that are not contained within decision blocks.
- d. Methods of Emphasis 1 ) Conditional terms shall be emphasized by underlining thJ term.
2.5 Functional Flow and Branchina
- a. Grouping of Paths 1 ) The spacing of paths shall be sufficient to allow operators easy and accurate movement through flowchart branches.
2 ) The direction of flow shall be apparent through the use of directional alrows.
- b. Ordering / Entry i ) Instructional and caution blocks shall be referenced immediately at or ahead of the blocks to which they apply.
2 ) There shall be adequate means for returning the user to the correct branch in the flowchart after exiting. y 3 ) Pathe! actions shall be presented in the order of importance, use, and especially technical necessity. 1 I _ _ __ _ _ _ _ __ _ _ ____ _ _ _ ___ _ _ _ _ __ ___ _ __ ___d
Appendix B, Rev. 3 - Writers' Gulc1 Daae 7 4 ) Due consideration shall be given to physical layout and organization of the Control Room when determining the sequencing of tasks.
- c. Consistency of Branching Methods 1 ) Branching methods shall be used consistently.
2.6 Readability /Stvfe
- a. Character Size 1 ) Character size shall be sufficient to permit rapid and accurate i recognition under conditions of normal and emergency 11ghting,
- b. Character Style 1 ) The character stylo shal'. meet human factors standards. {
2 ) The spacing between letters and words shall provide for rapid and , accurate character recognition. 3 ) Capitalization shall conform to standard English usage in the caution statements and appendices,
- c. Numerals 1 ) Numerals (repre-senting values of parameters or equipment designations) should be written in the style familiar to the operator.
2 ) Numerals should correspond to those designated on panels. 3 ) When used to refer to instrument readings, the operator should be able to immediately relate those numerals to those used on the instruments, without conversion, translation or manipulation. 2.7 ho of use
- a. Verification provisions i 1 ) The flowcharts shall be 'esigned to permit tracking of movement l through its branches.
- b. Size of Flowcharts l 1 ) Flowcharts shall be neither too large nor to small to interfere with their ease of use.
- c. Layout 1 ) Each flow chart shall be constructed in such a manner to present a l neat and uncluttered appearance.
- - - _ _ _ _ _ _ _ _ _ _ _ _ _ _ - _ _ _ - _ _ __ _A B
Appendix B, Rev. 3 - Writers' Guide pace 8 2 ) Separate and distinct step numbers shall be used at each step for quick and accurate identification. ) i 3 ) Entry and exit points will be clearly indicated using in and out arrows where they apply. 2.8 Flowchart fri auction Sten Lenath and Content i Flowchart instruction steps will be succinct and precise in that succinctness denotes brevity: preciseness means exactly and correctly defined. General rules to be used in meeting these objectives are as follows:
- a. Instruction steps should dMI with one idea only and written as a directive (imperative mode).
- b. Short, simple sentences should be used.
- c. Short words and words in common use shall be used, and used consistently.
- d. Nomenclature and idioms that the operator is trained to use and which are standard in the nuclear industry shall be used.
- e. Concrete and specific words.
- f. Adverbs which are difficult to define in a precise manner (e.g.,
frequently, slowly), shall be avoided if possible.
- g. Complex evolutions should be described in a series of steps, with each step made simple,
- b. Objects of operator actions should be specifically stated.
- i. Limits should be expressed quantitatively.
J. Identification of components and parts should be technically correct and complete.
- k. When actions are required based upon receipt of an annunciated alarm, the alarm set point should be listed.
- 1. If requked for proper understanding, describe the system response time associated with performance of the instruction.
- m. When system response dictates a time frame within which the instruction must be accomplished, denote the time frame. However, avoid using time to initiate operator actions, since operator actions should be related to plant parameters as much as possible.
- n. When anticipated system responses may adversely affect instrument indications. (1) describe the conditions that will likely introduce instrument error and, (2) describes a means of determining if instrument error has occurred using a CAUTION.
_ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _w e
Appendix B, Rev. 3 - Writers' Guide pace 9
- o. When additier.dl confirmation of system response is considered necessary, i prescribe the backup readings to be made.
2.? Use of Loole Terms l When logic stetements are used, logic terms will be emphasized so that all conditions are clear to the operator. Use logic terms as follows:
- a. Avoid the use of AND and OR within the same action. When AND and OR are used together, the logic can be very ambiguous,
- b. When attention should be called to combinations of conditions, the word AND shall be placed between the description of each conditinn. The word AND shall not be used to join more than three conditio" 4f four or more conditions need to be joined, a list format shall be used.
- c. The word OR shall be used when calling attention to alternative combinations of conditions. The use of the word OR shall always be in the inclusive sense,
- d. When action steps are contingent upon certain conditions or combination of conditions, the step shall begin with the words IF or WHEN followed by a description of the condition or conditions, a comma, and the word THEN followed by the action to be taken. WHEN is used for an expected condition. IF is used to determine the specific course of action based upon plant conditions.
- e. Use of IF NOT should be avoided.
2.10 Comoonent Identification The follov@1 rules are to be followed with regard to component identifictt2,1:
- a. Equipment, controls, and displays will be identified in operator language (commoa usage) terms.
- b. When the engraved names and numbers on legend plates and alarm windows are specifically the item of concern in the procedure, tne engraving should be quoted verbatim.
- c. The names of plant systems titles are emphasized by initial capitalization.
- d. If the component is seldom used or difficult to locate, location information should be given.
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Appendix B, Rev. 3 - Writars' Guide paae 10 2.11 Level of Detail The level of detail required is the detail that a newly trained and licensed operator would desire during an emergenoy condition. To assist in determining the level of detail, the following rules apply:
- a. For control circuitry that executes an entire function upon actuation of the control switch, the action verb appropriate to the component suffices without further amplification of how to manipulate the controi device; recommended action verbs to be utilized are:
1 ) For power-driven rotating equipment: Start, Stop 2 i or valves: Open, Close, Throttle Open, Throttle Close, Throttle 3; Qr power distribution breakers: Synchronize, Close, Trip.
- b. For multi-position control switches that have more than one position for a similar function, placement to the desired position must be specified.
2.12 Document Maintenance and Retention
- a. To ensure the maintenance of documentation required in support of revisions to the flowchart, a check-off sheet (see Figure 2) shall accompany all revisions of the flowchart.
- b. The retention of documentation relating to the development, implementation, and revision of the flowchart will be controlled in accordance with AP 6807 " Collection and Temporary Storage of Quality Assurance Records", and AP 6809 " Plant QA Records Management System".
3.0 APPENDICES GUIDELINES 3.1 OE Anoendix Numberina Each OE Appendix shall be uniquely identified. This identification permits easy administration of the process of procedure preparation, review, revision, distribution, and operator use. A descriptive title is to be used that l also designates the scope. 3.2 Anoendix Numberina Appendices will be identif:9d by both the procedure number (i.e., OE 31xx) and by alpha designation (i.e., Appendix A). 3.3 Revision Identification A change bar located in the left margin alongside the text change will be used to indicate a left-hand column change; a change bar located in the right i t - - - - - - - - - _ - - - - - - - - - - - - - - - - - , - _ _ _o
Appendix B, Rev. 3 - Writers' Guide oaae 11 margin alongside the text change will be used to indicate a right-hand column change. 3.4 Paan Identification and Numberina Each page of the procedure will be identified by: a The procedure number followed by the revisioti number
- b. The Appendix alpha designator
- c. The page number, written as "Page ._.of _.".
The procedure number and revision number will be located at the bottom of each page. The page number will be at the bottom of each page. 3.5 Paae Format A dual-column format will be used in which the left-hand column is designated for operator actions and notes, and the right-hand column is designated for information and caution. 3.3 Anoendix Organization The following section headings will be used for all Appendices:
- a. PREREQUISITES - A listing of any initial conditions which must be established before starting the procedure.
- b. PROCEDURE - A sequentia! listing of operator steps. The entry conditions will be those plant parameters which, when exceeded, require entry into and execution of the OE.
- c. RESTORATION A sequentiallisting of steps for returning of systems and conditions to normal. The operator actions will be succinct, identifiable instructions that give appropriate directions to the user.
3.7 Section Numberina i The following format will be utili::ed in section numbering: a The first section shall be designated by a capital letter.
- b. The second section shall be designated by a number.
- c. The third section (if required) shall be designated by a lower case letter.
I _..m_..
Appendix B. Rev. 3 - Writers' Guidt paos 12 3.8 Instruction Steo Lenoth and Content )1 Instruction steps will be succinct and precise and will be locr.ted in the instructions column of the right hand page. Succinct denotes brevity; precise l denotes exactly and correctly defined. General rules to be used in meeting these objectives are as follows: ) I
- a. Instruction steps should deal with one idea only.
- b. Short, simple sentences should be used.
- c. Complex evolutions should be described in a series of steps, with each I
step made simple.
- d. Objects of operator actions should be specifically stated.
- e. For instructional steps that involve an action verb relating to three or more objects, the objects will be listed with space provided for operator checkoff. ',
I
- f. Limits should be expressed quantitatively.
- g. Identification of components and parts should be technically correct and complete.
- h. When actions are required based upon receipt of an annunciated alarm, the alarm setpoint should be listed.
- i. If required for proper understanding, describe the system response time associated with performance of the instruction.
J. When system response dictates a time frame within which the instruction must be accomplished. denote the time frame. However, avoid using time to initiate operator actions, as operator actions should be related to plant parameters as much as possit,b.
- k. When anticipated system responce may adversely affect instrument indications, (1) describe the cono:tions that will likely introduce instrument error and, (2) describe s means of determining if instrument error has occurred by using a C AUTION.
- 1. When additional confirmation of system response is considered necessary, prescribe the backup readings to be made.
3.9 Use of Locic Terms Use logic terms as follows:
- a. Avoid the use of AND and OR within the same action. When AND and OR are used together, the logic can be very ambiguous.
s n
Appendix B. Anv. 3 - Writers' Guide pace 13 l-
- b. When attention should be called to combinaoons of conditions, the word AND shall be placed between the description of each condition. The word AND shall not be used to join more than two conditions. If two or more conditions need to be joined, a list format shall be used.
- c. The word OR shall be used when calling attention to alternative combinations of conditions. The use of the word OR shall always be in the inclusive sense.
- d. When action steps are contingent upon certain conditions or combinations of conditions, the step shall begin with the words E or WHEN followed by a description of the condition or conditions, a comma, and the word THEN followed by the action to be taken. WHEN is used for an expected condition. E is used to determine the specific course of action based upon.
plant conditions.
- e. Use of IF NOT should be avoided.
3.10 Comoonent identification The following rules are to be followed with regard to component identification: a Equipment, controls, and displays will be identified in operator language (common usage) terms.
- b. When the engraved names and numbers on legend plates and alarm windows are specifically the item of concern in the procedure, the engraving should be quoted verbatim and emphasized by using all capitals.
- c. The names of plant syJtems titles are emphasized by initial capitalization,
- d. If the component, controls or displays are infrequently used or difficult to.
locate, location information shall be provided. 3.11 Level of Detail The level of detail required is the detail that a newly trained and licensed operator would desire during an emergency condition. To assist in determining the level of detail, the following rules app!y: a For control circuitry that executes an entira function upon actuation of the control switch, the action verb appropriate to the component suffices without further amplification of how to manipulate the control device; recommended action verbs to be utilized are: I) For power-driven rotating equipment: Start, Stop. ] 2 ) For valves: Open, Close, Throttle Open, Throttle Close, Throttle 3 ) For power distribution breakers: Synchronize and Close, Trip. { I m - - ----_---_----_m - a
Appendix B, Rev. 3 - Writers' Guid5 page 14 i
- b. For multi-position control switches that have more than one position for a similar function: placement to the desired position should be specified.
3.12 General Tvolna Format The following general requirements are to be followed:
- a. Paper size should be 81/2 x 11 inches.
- b. White, bond paper should be used. {
3.13 Breakina of Words Breaking cf words shall be avoided. 3.14 Document Maintenance and Rotenf _.7,
- a. To ensure the mainte. nance of documentation required in support of revisions to the appendix, a check-off sheet (see Figure 2) shall accompany all revisions of the appendix.
- b. The retention of documentation relating to the development, implementation, and revision of the appendix will be controlled in accordance with AP 6807 " Collection and Temporary Storage of Quality Assurance Records", and AP 6809 " Plant QA Records Management System".
4.0 MECHANICS OF STYLE 4.1 Soeliina Spelling should be consistent with modern usage. When a choice of spelling is offered by a dictionary, the first spelling shoulc: be used. 4.2 Hvohenation Hyphens are used between elements of a compound word when usage calls for it. The following rules should be followed for hyphenation:
- a. When doubt exists, the compound word should be restructured to avoid hyphenation.
- b. Hyphens should be used in the following circumstances:
1 ) in compound numerals from twe.7ty-one to ninety-nine, 2 ) in fractions, 3 ) in compounds with "self",
, n
Appendix B. Rev. 3 - Writers' Guide pace 15 4 ) when the last letter of the first word is the same vowel as the first letter of the second word, 5 ) when misleading or awkward consonants would result by joining the words, 6 ) to avoid confusion with another word, 7 ) when a letter is linked with a noun. 4.3 Punctuation Punctuation should be used only as necessary to aid reading and prevent misunderstanding. Punctuation should be in accordance with the following rules:
- a. Brackets Brackets are not to be used.
- b. Colon Use a colon to indicate that a list of items is to follow,
- c. Parentheses Parentheses shall be used to indicate altemative items in a procedure, instruction, or equipment numbers,
- d. Period Use a period at the end of complete sentences and for indicating the decimal place in numbers. ,
4.4 Vocahularv Words used in procedures should convey the proper understanding to the trained person. The following rules apply:
- a. Utilize simple words (i.e. short words of few syllables).
- b. Utilize common usage.
- c. Utilize words that are concrete rather than vague, specific rather than general, familiar rather than formal, precise rather than blanket.
- d. Define key words that may be understood in more than one sense.
- e. . Verbs with specific meanings should be used.
% f
Appendix B, Rev. 3 - Writ *rs' Guide paae 16
- f. Equipment status should be denoted as follows:
1 ) Operable / Operability /Available - These words mean that a system, subsystem, train, component, or device is capable of performing particular function (s). 2 ) Operating - This word means that a system, subsystem, train, component, or device is in operation and is performing its specified function. 4.5 Numerical Values The use of numerical values should be consistent with the following rules:
- a. Arabic numerals should be used.
- b. For numbers less than unity, the decimal point should be preceded by a zero; for example: 0.1.
- c. The number of significant digits should be equal to the number of significant digits available from the display (and required by the necessary reading precision of the operator).
- d. Acceptance values should be specified in such a way that addition and subtraction by the user is avoided if possible. This can be done by stating acceptance values as limits.
- e. Engineering units should always be specified for numerical values of process variables, and'should be the same.
4.6 Abbreviations. Letter Symbols. and Acronyms
- a. The use of abbreviations should be minimized. Abbreviations may be used where necessary to save time and space, and when their meaning is unquestionably clear to the intended reader. Consistency should be maintained throughout the procedure. Table 1 contains a listing of common abbreviations used at Vermont Yankee.
- b. Use of abbreviations for standard engineering units shall conform to common useage.
- c. Capitalization of abbreviations should be uniform. If the abbreviation is comprised of lower case letters, it should appear in lower case in a title or heading. The period should be omitted in abbreviations except in cases where the omission would result in confusion.
i
- d. Letter symbols may be used to represent operations, quantities, elements, relations, and qualities.
l 2 ,
Appendix B, R?v. 3 - Writers' Guide pace 17 EMERGENCYOPERATING PROCEDURES FLOWCHARTSYMBOLS i Procedure entry conditions. Procedure title or geneal Instructions. Decision blocks. A yes or no answer must be decided upon to determine the appropriate path on which to continue in he procedure. OE)000( Exit this procedure and proceed to the indicated procedure and step. For he color-enhanced, SEND mounted versions, the arow is color-coded to correspond to the colored border of the applicable EOP. OE)000( Proceed to the indicated procedurc and step AND continue in this procedure. For the color-enhanced mounted versions, the arow is color-coded to
~
$$ correspond to the colored border of the applicable EOP, OE)000( This procedure entered from the indicated procedure and step. For he color enhanced, h! INN mounted versions, the arow is color-coded to correspond to the colored border of the applicable EOP.
O The number within the circle indicates the caution applicable to ths step. Dashed lines indicate the items connected relate referenced in a given step). Figure 1. EOP Flowchart Symbols - - _ _______ _ - __-______ __-_________ - -__ - _ s ___- _____. . _ _ _ _ _ _ _ o_
Appendix B, Rev. 3 - Writers' Guide pace 18 EOP Revision Checklist OE Revision Prepared by: date: Reason for change: i YES NO i
- 1. Revision of the Procedure Generation Package required? m
- 2. Revision of the Technical Justifications required? m
- 3. Revision of EOP calculations required?
- 4. Verification / Validation of revised procedure required? m For those questions responded to with a YES, attach the applicable documentation to j l this form.
I approved: date Senior Operations Engineer 1 Figure 2. EOP Revision Checklist
]
)
l l t t )
Appendix B, Rev. 3 - Writers' Guide pace 19 TABLEI 3 ABBREVIATIONS ADS Automatic Depressurization System ALT Alternate APRM Average Power Range Monitor ARI Alternate Rod Insertion l CRD Control Rod Drive i l CRP Control Room Panel CST Condensate Storage Tank CUFD Cleanup Filter Demineralized D/G Emergency Diesel Generator (s) EDCS Emergency Core Cooling System ED Emergency Depressurization FDW Feedwater KXJ Hydraulic Control Unit HPCI High Pressure Coolant injection HVAC Heating, Ventilating and Ak Conditioning j INJ Injection { IRM Mermediate Range Monitor j LOD c citing Condition for Operation ! LOCA Loss of Coolant Accident LPCI Low Pressure Coolant injection CS Low Pressure Core Spray MSIV Main Steamline Isolation Valves MSL Main Steam Line NPSH Net Positive Suction Head G Operational Emergency procedure CP Operating Procedure PCIS Primary Containment Isolation System PTS Points RCIC Reactor Core Isolation Cooling RECIRC Recirculation RHR Residual Heat Removal RHRSW RHR Service Water RPS Reactor Protection System RPT Recirculation Pump Trip RPV Reactor Pressure Vessel RRU Reactor building Recirc Unit RWCU Reactor Water Cleanup Rx Reactor SGilS Standby Gas Treatment System S/D Shutdown SOV Scram Discharge Volume l EUAE Steam Jet Air Ejector l SLC Standby Liquid Control SRM Source Range Monitor SRV Safety Relief Valve TAF Top of Active Fuel l TRANS Transformer f _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ n o
~ - - - - - - - - _ _ _ . _
APPENDIX C OE VALIDATION USING TABLE-TOP METHOD 1 l - - - - _ _ - _ _ _ _ _ _ _ _ _ _ _ . _. . _ _ _ 3 f
RQv. 3 APPENDIX C OE VALIDATION USING TABLE-TOP METHOD The table-top method consists of four phases: planning, preparation for and conducting the evaluation, and resolving the OE discrepancies which are found during the evaluation. 1.0 PLANNING THE TABLE-TOP METHOD The planning phase consists of the following activities: 1.1 Desig.. ate Evaluator (s) - When the table-top method has been designated as being the most effective method for a given validation session, an evaluator who is skilled in plant operations, procedures, training and test evaluation methods will be appointed. 1.2 Review the Test Plan
- a. Purpose of conducting the validation
- 1) Specific objective (s) to be tested
- 2) Applicable principles and guidelines
- b. Selection of scenarios required to satisfy validation objectives to be tested.
- c. How OE changes are to be tested
- d. Detection and classification of errors
- e. Administration of test plan 2.0 PREPARING FOR THE TABLE-TOP After the resources to support the table-top have been selected, the evaluator (s) will:
2.1 Arrange for use of required OEs, specifications, and related l technical documentation. 2.2 Arrange for the use of room equipped with adequate surface to i lay out OEs and related documentation. ) i 2.3 Review event scenarios already developed and select these which ! I are appropriate for the table-top method. 2.4 Arrange for the use of required plant personnel, giving con-sideration to the advantages / disadvantages of the following arrangements that can be used with the table tops a '. One-on-One - One member of the observer / review team and one plant person. Page 1 of 2 s R 1
Appandix C Rav. 3
- b. One-on-Crew - One member of the observer / review team and an operating crew.
- c. T,eam-on-Crew - The observer / review team and the operating crew.
- d. Team-on-One - The observer / review team and one plant person.
3.0 CONDUCTING THE TABLE-TOP 3.1 The evaluator (s) shall:
- a. Provide a copy of the OEs to be validated and debriefing forms.
- b. Review the overall objective and technique of the table-top with plant personnel who are taking part in the validation.
- c. Provide the plant personnel with a copy of the OEs to be validated.
- d. Review the use of the debriefing form with the plant personnel,
- e. Provide plant personnel and evaluators with a copy of the scenarios.
i
- f. Review the event-sequences and scenarios and any underlying assumptions about them.
3.2 Plant personnel shall
- a. Use the OEs as the evaluator (s) lead them through the '
scenario. 3.3 At the end of the scenarios, the evaluator should:
- a. Interview the plant person (s) to find out i f the appli-cable OE changes are understandable and sensible in terms of operating the plant. i
- b. Document discrepancies which are found in the OEs.
- c. Forward a copy of discrepancies to the Senior Operations Engineer.
Page 2 of 2 y
---________.m . _ _ _ _ _ _ _ _ _ _ _ _ __
g
APPENDIX D I OE VALIDATION USING WALK-THROUGH METHOD l 1 j 1 1 1 I m , -
Rev. 3 APPENDIX D DE VALIDATION USING WALK-THROUGH METHOD 1.0 REVIEW THE TEST PLAN As part of planning for a walk-through, a test plan will be developed. Developing a test plan will require consideration of the following: 1.1 Purpose of conducting the validation
- a. Specific objective (s) to be tested i
- b. Applicable principles and guidances Selection of scenarios required to satisfy validation objectives to 1.2 be tested.
1.3 How OEs are to be used. 1.4 Detection and classification of errors 1.5 Administration of test plan 2.0 PREPARING FOR THE WALK-THROUGH 2.1 After the resources to support the walk-through have been selected, the evaluator (s) will:
- a. Provide the plant personnel with a copy of the OE changes to be, validated.
- b. Review the use of the observation and debriefing forms with the plant personnel,
- c. Review with event sequences and scenarios and any underlying assumptions about them,
- d. Arrange for use of specific type of equipment
- 1) Real equipment
- 2) Dynamic simulators
- 3) Mock-up A) Operator auxiliary equipment (e.g., respirators, protec-tive clothing, radiation detectors) if required
- 5) Audio / Visual (A/V) equipment
- e. Arrange for the use of required personnel
- f. Review event scenarios already developed and select those which are appropriate for the walk-through method.
Page 1 of 2
\
__ __ - - - - - - - - - - - . )
Appendix D Rev. 3 3.0 CONDUCTING THE WALK-THROUGH l 3.1 The evaluator (s) shall:
- a. Review 'the responsibilities
- b. Review the overall objective and techniques of the walk-through with plant personnel who are participating in the walk-through.
3.2 Plant personnel shall: Walk / talk through actions they would take during specific l a. situations covered by the event-sequence (s) and scenario (s).
- b. Describe actions they are taking.
- c. Identify information sources used to take actions.
- d. Identify controls used to carry out actions, expected system response (s), how response (s) verified, and action (s) to be taken if response (s) did not occur.
3.3 The Evaluator (s) shall:
- a. Direct walk-through
- b. Coordinate efforts of plant personnel and track usage of the applicable OEs.
- c. Review scenario (s)
- d. Ask appropriate "what if" questions
- e. Note problems and discrepancies encountered by plant personnel.
Page 2 of 2
APPENDIX E OE VALIDATION USING SIMULATOR METHOD 1 l l
)
v t )
RQv. 3 APPENDIX E DE VALIDATION USING SIMULATOR METHOD
1.0 INTRODUCTION
1.1 Background
The goal of the upgraded Emergency Operating Procedures is to improve human reliability and the ability to mitig;te the consequences of a broad range of initiating events and subesquent multiple failures or operator errors, without the need to diagnose specific events. A functional orientation, rather than event basis, and human factors considerations are incorporated into the Emergency Operating Procedures to achieve this end. This document is intended to fulfill a portion of the requirements for a description of the validation plan, i.e., a description of the Emergency Operating Procedures (EOPs) Simulator Validation Plan. 1.2 Objective and Scope Whenever this process is used, the following objectives for the pro-cedure process should be ensure:
- a. The E0Ps are technically correct, i.e., they accurately reflect the technical guidelines.
- b. The EOPs are written correctly, i.e., they accurately reflect the plant-specific writer's guide. ,
- c. That E0Ps are usable, i.e., they can be understood and followed without confusion, delays, errors, etc.
- d. That there is a correspondence between the procedures and the cc9 trol room / plant hardware, i.e., control / equipment / indications that are referenced, are available (inside and outside of the control room), use the same designation, use the same units of measurement, and operate, as specified in the procedures,
- e. That the language and level of information presentation, in the E0Ps is compatible with the minimum number, qualifications, training and experience of the operating staff,
- f. That there is a high level of assurance that the procedures will work, i.e., the procedures guide the operator in miti-gating transients and accident.
During the simulator runs, the actual useability of the procedures (objective "c") will be the focus of the process. All the objectives will be evaluated to some extend during the simulator validation. The use of the simulator will provide the high level of assurance that the procedures will work as proposed in objective "f". Page 1 of 4
Appendin E Rev. 3 2.0 METHOD FOR SIMULATOR VALIDATION 2.1 Performance of Simulator Runs The simulatoF runs will provide an objective context in which to evaluate the useability of the p~ocedures. In contrast to walking through the procedures in a static environment, in which dynamic pro-cedural problems may be overlooked, the simulation environment will mimic the operating conditions for a more objective challenge to the procedures. The simulation will also provide a setting in which the operators can be faced with a reasonably realistic emergency situation for which they must diagnose the symptoms and proceed accordingly using the new procedures. The operating crew chosen for the simulator runs will have been fami-liarized with the new procedures during training. The crew will not be briefed on the actual scenarios to be run. The operators will, however, be briefed on the purpose of the validation. It will be made clear to them that it is not their performance that is being evaluated, but the performance of the new procedures. Each scenario may be simulated separately with a debriefing session after the run or together depending on the evaluator opinion or the complexity of the changes being validated. During the simulator runs, if the crew takes an acceptable alternate path that is as correct as the expected path, they will be allowed to continue uninterrupted. If the operating crew momentarily takes an unexpected alternate path that is an incorrect path, and are able to ' get back on the correct path using the procedure within a reasonable amount of time, the simulation should continue undisturbed. If, however, the crew takes an unexpected alternate path that is incorrect and shows no sign of recovering the simulation will be stopped. If an obvious, remediable error is involved, the problem should be corrected and the run started again where it went astray. If, however, the problem is not obvious or readily remediable the simulator run will have to be postponed until such time as the problem is diagnosed or corrected. 3.0 ANALYSIS AND RESOLUTION 3.1 Debriefing of Operators The operator debriefing session will be conducted immediately after each scenario run on the simulator. The comments of the operators who have participated in the exercise provide one of the most impor-tant sources of information for evaluating the procedure set. Operator actions which do not lead themselves to direct observation, such as symptom diagnosis or conversion of displayed values can be described by the operators during the debriefing. The operators' Page 2 of 4
Appandix E Rev. 3 3.1 Debriefing of Operators (Continued) 5'omments also contribute to greater accuracy in analyzing deviations from expecte( operator actions which occurred during the scenario. It is essential that the operators be debriefed as soon as possible after the scenario has been completed so that their comments on the events of the scenario will be comprehensive. A validation team member or simulator instructor will explain the debriefing process and its purpose to the operators and elicit from them general comments on the impact of the procedures on their per-formance. The operators will be asked to discuss procedure-related problems they encountered during the scenario, and they will be asked to identify possible reasons for any procedure-rela;ad problems that. they encountered during the run. The operators will also be asked to present potential solutionc to any procedure-related problems. All discrepancies, comments, possible reasons, and potential solutions identified during the debriefing will be documented on paper and sub-mitted to the Senior Operations Engineer for evaluation. It becomes part of the procedure change package. 3.2 Procedure Change Analysis The purpose of analyzing the validation is to identify any discrepan-cies between expected operator actions and actual operator actions and, have any potential shortcomings in the procedures. Each discre-pancy identified during the debriefing will be analyzed on a case-by-case basis to determine if it is an error or if it is an acceptable discrepancy and should be deleted from consideration. A discrepancy , that impacts adversely on operator performance or plant condition should be considered an error. An example of an acceptable discre-pancy would be an operator action in a sequence that is different from the expected order but equally admissible. The Senior Operations Engineer will then use the evaluation criteria presented in the simultor debriefing guidelines to assist him in determining whether an error was due to a procedural problem or other causes such as control room hardware, training, or manpower. Errors which can be identified as being caused by procedural shortcomings will be resolved. When the procedure-related errors have been iden-tified, these errors may be categorized as follows:
- 1) Error of omission (intentional or unintentional)
. Omits an entire task
. Omits a step in a task Page 3 of 4 1
e - - - - - _ - _ _ - - . _ _ _ _ - - _ - _ _ _ __ _ . . _ . n
Appandix E , Rsv. 3
- 2) Error of commission
. Selection error
- Selects wrong control
- Dispositions control
- 3) Error of sequence
- 4) Time error
. Too early
. Too late
- 5) Qualitative error
. Too little
. Too much
4.0 REFERENCES
- 1. U.S. Nuclear Regulatory Commission, " Supplement 1 to NUREG-0737, "USNRC Generic Letter No. 82-33, December 1982.
- 2. U.S. Nuclear Regulatory Commission, " Guidelines for the Preparation '
of Emergency Operating Procedures", USNRC Report NUREG-0899, August 1982. Available from the U.S. Government Printing Office, ' Washington, D.C. 20402.
- 3. The GOPIA Review Group, " Emergency Operating Procedures Validation Guideline". The Institute of Nuclear Power Operations, Atlanta, Georgia, January 1983.
Page 4 of 4 _ - - - _ _ - _ - _ . - - - -_ . - . _ . _. Q. 0
i APPENDIX F SIMULATOR DEBRIEFING GUIDELINES e e
\ l Rev. 3 APPENDIX F SIMULATOR DEBRIEFING GUIDELINES Scenario: , f Date: Emergency Operating Procedure Validation Guidelines for Debriefing i The following validatien criteria are presently in the form of questions and are to be used as gJideliness only to provide structure to the debriefing process. This validation should not only address changes to the respective OE but also any interaction the change (s) have with other Operational Emerpency Procedures. Evaluator (s) should check whether a criterion has been met or indicate N/A if the criterion could not be evaluated or was not applicable. Procedure-related problems, indicated on this form by "N", can be documented in greater detail using the attached comments (e.g., whether it is a generic problem or occurs at one step in a procedure). 1.1 Useability
- a. Level of Detail ,
- 1) Was there sufficient information to perform the spe-cified actions at each step?
- 2) Were all alternatives explicit at each decision point?
- 3) Could the operator use labeling, abbreviations, and location information as provided in the E0Ps to find the needed ecuipment?
- 4) Were the E0Ps missing information needed to manage the emergency condition?
- 5) Here the contingency actions as stated in the E0Ps sufficient?
- 6) Were the titles and numbers adequate to find referenced or branched procedures?
Page 1 of 3 i
Appendix F Rev. 3
- b. Understandability
,,___ 1) Was the typeface easy to read?
- 2) , Were the emphasized items noticed?
- 3) Were the applicable figures and tables easily and accurately read?
- 4) Was interpolation of values on figures and charts difficult?
- 5) Were caution and note statements understood?
- 6) Was the organization of the E0Ps understood?
?) Was the EOP step understood?
- 8) Were the step sequences understood?
- 9) Could the operator find the particu1&r step or set of steps when required?
- 10) Could the operator return to the procedure exit point s without omitting steps when required?
- 11) Could the operator enter the branched procedure at the correct point?
- 12) Could the operator exit from a given E0P at the ,
correct branch? 1.2 Operability Correct
- a. Technical Correctness
- 1) Were the instructions appropriate for the emergency condition?
- 2) Were the procedure actions able to be performed on the plant in the designated sequence?
- 3) Did the operator find alternate success paths not in the EOPs?
- 4) Was the procedure action able to be performed on the plant at the designated time intervals?
- 5) Could the operator obtain the necessary information from designated plant instrumentation when required by the procedure?
- 6) Did the plant symptoms direct the operator to the applicable EOP by its entry conditions?
Page 2 of 3 l .
Appandix F Rsv. 3 z l { j
- b. Compatibility )
~~
- 1) Were the E0P instructions compatible with the operating shift manning? _
- 2) Were the procedure ac+ ions able to be performed by the operating shift?
- 3) Did the EOPs help coordinate the actions of the j operating shift?
- 4) Did the operator have to use responses or other equipment not rpecified in the EOPs to accomplish his task?
- 5) Did the plant conditions seen by the operator correspond to what was in the E0P?
- 6) Were the instrument readings and tolerances con-sistent with the instrument values stated in the EOP?
l
- 7) Were the operators able to distinguish the E0P from other procedures in the control room?
- 8) Were the E0Ps physically compatible with the work situation (to bulky to hold, binding wouldn't allow them to lay flat in work space, no place to lay the '
E0Ps down to use)?
- 9) Was the plant condition compatible with the action which the EOP directed to be performed at a time interval or specified time?
- 10) Was the operating shift able to follow the designated action step sequences.
.1) Did the plant conditions allow the operator to correctly follow the action step?
Signature of Evaluator l DEL: mmh:PCP1.1/7 Page 3 of 3
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TABLE OF CONTENTS i GUIDEUNE/ CONTINGENCY , PAGE RPVCONTROL............................................................................................................1 PRIMARYCONTAINMENTCONTROL ...............................................................................20 SECONDARY CCM TAINMENT CONTROL .........................................................................61 RADIOACTIVITY RELEASE CONTROL .............................................................................79 C1 - LEVEL RESTORATION .........................................................................................81 C2 - EMERGENCY RPV DEPRESSURtZATION .......................................................... ......... 9 4 C3 - ST EAM COO U N G . . . . . . . . . . . . . . . . . . . . . .. . . .. . . . . .. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. . . . . . . . . . . . . . . . . . . . . . . . . . . .. . C4 - CORE COOUNG WITHOUT LEVEL RESTORATION ................... .................. ................. 1 0 2 C5 - ALTERNATE SHUTDOWN COOLING .................................................................N/A C6 - RPV FLOODING .......................................................................................................105 C7 - LEVEL / POWER CONTROL ....................................................................................115 OPERATOR PRECAUTIONS ......................................................................................119 I t _ ______ ___ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ . _ _ _ _ - . _ _ - O-
l JUSTIFICA N l Justification for Deletion, Deviation, or Addition to the BWROG Emergency Procedure Guideline, Rev.3 (DEV. DEL. A00) l l l EPG Guideline / Contingency: RPVCONTROL I EPG Section: Purpose EPG Step: na EPG Statement: 100'F< RPV water temperature <212'F (cold shutdown conditions) l EPG Basis: Definition of RPV water temperature for cold shutdown conditions. PSTG Guldeline/ Contingency: RPV Control PSTG Section: Purpose PSTG Step: na PSTG Statement: RPV water temperature < 212'F (cold shutdown conditons) PSTG Justifleetion: Vermont Yankee Tech Spec definition of RPV water teniperature for cold shutdown conditions is " reactor coolant temperatu'e equal to or less than 212'F". No lower limit for temperature is necessary. JDDA -1
- _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ o a
[ l i I JUSTIFICATION Justification for Deletion, Deviation, or Addition to the BWROG Emergency Procedure Guideline, Rev.3 l EPG Guideline / Contingency: RPVCONTROL EPG Section: Entry Conditions EPG Step: na EPG Statement: RPV water level below [+12 in. (Iow level scram setpoint)) l 1 l EPG Basis: l The low water level level entry condition directly addresses loss of coolant accidents, as well as loss of ; feedwater transients. PSTG Guldeline/ Contingency: RPVCONTROL PSTG Section: Entry Conditions PSTG Step: na PSTG Statement:
. RPV water level below +127 inches (Iow level scram setpoint) or level cannot be determined ESIQ Justification:
If water level car'1ot be determined, it is prudent for the operator to assume that a low water level condition exists. JDDA - 2 l 1 s G
JUSTIFICATION Justification for Deletion, Deviation, or Addition to the BWROG Emergencv Procedure Guldeline, Rev.0
~
(DEV. DEL. ADO) EPG Guldeline/ Contingency: RPVCONTROL ) EPG Section: Entry Conditions EPG Step: na EPG Stater, g .
- RPV pressure above [1045 psig (high RPV pressure scram setpoint))
I EPG Basis: The high RPV pressure entry condition d:rectly addresses safety relief valve failure events, and turbine trip with bypass valve failure events. PSN Guldeline/ Contingency: na PSTG Section: na PSTG Step: na PSTG Statement: na PSTG Justifientiom it is not appropriate for an event based ontry conditon to be used for symptomatic based emergericy operating procedures. Vermont Yankee uses event based operating procedures (ONs and OTs) to ac: dress these types of events (i.e., OT 5118 - Poactor High Prossure Procedure), i JDDA - 3
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1 JUSTIFICA N Justification for Deletion, Deviation, or Addition to the BWROG Emergency Procedure Guideline, Rev.3 (DEV. DEL. ADO) EPG Guideline / Contingency: RPVCONTROL EPG Section: Entry Conditions EPG Step: na , EPG Str9tement:
- Drywell pressure above [2.0 psig (high drywell pressure scram setpoint)]
EPG Basis: The high drywell pressure entry condition directly addresses .vss of coolant accidents due to breaks inside the drywell irrespective of makeup capacity to the RPV, and loss of drywell cooling events. PSTG Guideline / Contingency: na PSTG Section: na PSTG Step: na PSTG Slptemen11 na PSTG Justif tentio n: It is not appropriate for an event based entry conditon to be used for symptomatic based emergency operating procedures. Vermont Yankes uses event basod operating procedures (ONs and cts) to address thne types of svents (i.e., OT 3111 High Drywell Pressure Procedure). JDDA - 4
1 I JUSTIFICA Justification for Deletion, Deviation, or Addition to the BWROG Emergency Procedure Guideline, Rev.3 (DEV DEL., A00) EPG Guldellne/ Contingency: RPVCOMTOL EPG Section: Entry Conditions EPG Step: na EPG Statement:
. A condition which requires MSIV isolation l
l l l EPG Basts: The MSIV isolation entry condition directly addresses steam line breaks which occur downstream of the l MSIVs, and fuel element failure events. ) PSTG Guidellne/ Contingency: na PSTG Section: na PSTG Step: na PSTG Statement: na PSTG Justifleetion: It is not appropriate for an event based entry conditon to be used for symptomatic based emergency operating proceduren. Vermont Yar.kee uses event based operating procedures (ONs and OTs) to address these types of events (i.e., OT 3115 - Reacter Low Pressure Procedure, and OT 3112 - Main Steamline High Radiatior, Procedure). 1 JDDA - 5 n
t JUSTIFICA N Justification for Deletion, Deviation, or Addition to the BWROG Emergency Procecure Guideline, Rev.3 (DEV.OEL. ADD) EPG Guldeline/ Contingency: na EPG Section: na EPG Step: na EPG Stat:' ment: na 1 EPG Basis: na J PSTG Guideline / Contingency: RPVCONTROL PSTG Section: RC/L PSTG Step: na PSTG Statement: Caution #1 PSTG Justifleation: As a reminder, a caution to the operator was added to monitor the general state of the plant, and to enter the appropriate EOP if an entry condition for that EOP occurs. I JDDA - 6 __9 __ _ -__ __.___._____n_______________
Justification for Deletion, Deviation, or Addition msmCA N e: DEL to the BWROG Emergency Procedure Guideline, Rev.3 (DEV. DEL. A00) EPG Guideline / Contingency: RPV CONTROL EPG Section: RC/L EPG Step: RC/L 1 EPG Statement: If while executing the following step Boron injection is required, enter (procedure developed from CONTINGENCY #7j. EPG Basis: When Boron Injection is required, the actions required for control of RPV water level differ from those prescribed in step RC/L 2; additional factors must be considered in determining which RPV water level range should be maintained, which injection subsystems and alternate injection subsystems should be used, and what injection flow rate should be established. PSTG Guideline / Contingency: na PSTG Section: na PSTG Step: na PSTG Statement: na L PSTG Justification: CONTINGENCY #7 has not been implernented at Vermont Yankee. See Justification for deletion of this l l contingency. I l l l i i l JDDA - 7
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1 WSMCA Justification for Deletion, Deviation, or Addition 1 DEL E. to the BWROG Emergency Procedure Guideline, Rev.3 (DEV. DEL ADD) 1 EPG Guidellne/ Contingency: RPVCONTROL EPG Section: RC/L EPG Step: RC/L-2 EPG Statement: Restore and maintain RPV water level . with one or more of the following systems: HPCS EPG Basis: Specification of systems appropriate for controlling water level. PSTG Guideline / Contingency: RPVCONTROL PSTG Section: RC/L PSTG Step: RC/L-2 PSTG Statement: na PSTG Justifleutlon: Vermont Yankee does not possess a High Pressure Core Spray (HPCS) System. JDDA -8 l l
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JUS M CA O" Justification for Deletion, Deviation, or Addition pE: DEL to the BWROG Emergency Procedure Guideline, Rev.3 (DEV. DEL. ADD) EPG Guldellne/ Contingency: PPVCONTROL EPG Section: RC/L EPG Step: RC/L-2 EPG Statement: [.. psig (RPV pressure range for system operation)] EPG Basis: RPV pressure range notations are provided as operator aids. PSTG Guideline / Contingency: RPVCONTRL PSTG Section: RC/L PSTG Step: RC/L-2 PSTG Statement: n/a PSTG Justiffeation: Operator knowledge from training, system surveillance and operating experience is sufficient. The operators do not feel the need for this aid. i
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Justification for Deletion, Deviation, or Additlen msmc " E: DEV to the BWROG Emeroency Procedure Guideline, Rev.3 (DEV DEL. ADD) EPG Guideline / Contingency: RPVCONTROL EPG Section: RC/P EPG Step: RC/P 1 EPG Statement: If any SRV is cycling, initiate IC and manually open SRVs until RPV pressure drops to (935 (RPV pressure at which all turbine bypass valves t.re fully open)]. EPG Basis: Manual initiation of the isolation condenser (IC) to control RPV pressure, and reduction of RPV pressure to substantially below the lowest SRV lifting setpoint to minimize the number of challanges to the SRVs. PSTG Guideline / Contingency: RPVCONTROL PSTG Section: RC/P PSTG Step: RC/P-1 PSTG Statement: If any SRV is cycling, manually open that SRV until RPV pressure drops to 950 psig (RPV pressure at which all turbine bypass valves are fully open). PSTG Justification: Vermont Yankee has no isolation condenser. When a SRV is cycling, the total number of SRV actuations is minimized if only the cycling SRV is manually opened. Manually opening sli SRVs urinocessarily challangos any SRVs which were not cychng. JDDA 10
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i JUSTIFICATION Justification for Deletion, Deviation, or Addition to the BWROG Emergency Procedure Guideline, Rev.3 (DEV. DEL. ADD) EPG Guideline / Contingency: RPVCONTFOL EPG Section: RC/P EPG Step: RC/P-1 EPG Statement: If while executing the following steps:
- Boron Injection is required, and
- The main condenser is available, and
+ There is no indication of gross fuel failure or steam line break, open MSIVs to re-establish the main condenser as a heat sink.
EPG Basis: The plant condition requiring Boron Injection is "the reactor cannot be shutdown before suppression pool temperature reaches the Boron injection initiation Temperature.. ". If the total energy to be released is discharged solely to the suppression pool, the Heat Capacity Temperature Limit could quickly be reached. Therefore, with the reactor not shutdown, utilization of the main condenser as the heat sink is of sufficient importance to warrent opening the MSIVs given that the main condenser is available and there is no indication of gross fuel failure or steam line break. PSTG Guidellne/ Contingency: RPVCONTROL PSTG Section: RC/P PSTG Step: RC/P-1 PSTG Statement: If while executing tho following steps: The main condenser is available, and
. There is no indication of gross fuel failure or steam line break, open MSIVs to re-establish the main condenser as a heat sink.
PSTG Justiflg.gflgm Any time the main condenser is available and it is safe to do so, the operator is instructed to use it rather than the suppression pool as the heat sink. In this case, the EPGs apply those . restrictions plus the added restriction that boror injection is required. This is an unnecessary restrict lon since it needlessly challanges the suppression pocl's heat capacity, and delays re-establishment of the main condenser as the heat s'nk. ; l JDDA - 11 _._ - _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ __ . O
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JUSTIFICATION Justificatlors for Deletion, Deviation, or Addition to the BWROG Emergency Procedure Guldeline, Rev.3 (DEV. DEL. A00) EPG Guldeline/ Contingency: RPVCONTROL j EPG Section: RC/P EPG Step: RC/P-2 EPG Statement: If the continuous SRV pneumatic supply is or becomes unavailable, depressurize with sustained SRV opening. I l EPG Bosis: Loss of the continuous SRV pneumatic supply limits the number of times that an SRV can be cycled since pneumatic pressure is required for valve operation, and the SRV accumulators contain a limited supply, if SRVs must be used to augment RPV pressure control and if the continuous SRV pneumatic supply is or becomes unavailable, the valve should be closed to limit the number of cycles on the valve and conserve pneumatic pressure so that if Emergency Depressurization is subsequently required, the valve will be available for this purpose. If other pressure control systems are not capable of maintaining RPV pressure below the lowest SRV lifting pressure, the SRV will still open upon reaching its lift pressure. PSTG Guideline / Contingency: RPVCONTROL PSTG Section: RC/P PSTG Step: RC/P 2 PSTG Statement: na PSTG Justification: The C.PG statement conilicts witn the EPG basis in that the direction given to the operator will net conserve the pneumatic supply present in the SRV accumulator. In step RC/P-2, the operalor is given a list of systems to c.ugment RPV pressure control via the turbine bypass vatves. HPCI and/or RClO are listed as first choices for pressure cantrol to limit SRV use, th6reby conserving pneumatic prescure supply. Add l:ionaUy, the ritrogen supplied manifold may be charged via alternate methods for insuring
- long-term SR'/ operability. ,
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Jus m CA " Justification for Deletion, Deviation, or Addition E: DEV to the BWROG Emergency Procedure Guideline, Rev.3 (DEV, DEL. A00) EPG Guidellne/ Contingency: RPVCONTROL EPG Section: RC/P EPG Step: RC/P 2 l EPG Statement: Control RPV below [1090 psig (lowest SRV lifting pressure)) with the main turbine bypass valves. EPG Basis: Control of RPV pressure be!cw the lowest lifting SRV setpoint pressure eliminates further challanges to the SR'/s, preserves the heat capacity of the suppression pool, and simplifies RPV water level control actions be eliminating fluctuation and oscillations in RPV water level. PSTG Guldeline/ Contingency: RPVCONTROL PSTG Section: RC/P PSTG Step: RC/P-2 PSTG Statement: Control RPV below 1055 psig (high RPV pressure scram setpe;nt) with the main turbine bypass valves. PSTG Justification: Since the high RPV pressure scram setpoint is less than the lowest lifting SRV setpoint pressure, the choice of the former not only satisfies the EPG basis, but also permits resetting of the scram solenoids. JDDA - 13 6 O
JUSTIFICA Justification for Deletion, Deviation, or Addition to the BWROG Emergency . Procedure Guideline, Rev.3 (DEV. DEL. ADD) EPG Guldeline/ Contingency: FFVCONTROL EPG Section: RC/P EPG Step: RC/P 3 l EPG Statement: When either: The reactor is shutdown and no boron has been injected into 'he RPV, depressurize the RPV and maintain cooldown below [100*F/hr (RPV cooldown rate LCO)]. EPG Basis: If not all rods are inserted beyond the Maximum Subcritical Banked Withdrawal position and no boron has been injected, but available instruments indicated that the reactor is shutdown, commencement of RPV depressurization and cooldown is permitted even though the actual reactor shutdown margin may be unknown. PSTG Guideline / Contingency: RPVCONTROL PSTG Section: RC/P lPSTG Step: RC/P-3 PSTG Statement: na PSTG Justification: This criteria has been eliminated due to the uncertainty of the actual shutdown margin (the condition could require a greater degreo of knowledge than is possessed by the average operator), and the seriousness of the consequences of depressurization and cooldown without positivo (, confirmation of reactor snutdown. { l JDDA - 14 _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ - . _ _ _ _ _ . . . _ . . _ . . _ _ _ . .s. _ o
l l JUSTIFICA N Justification for Deletion, Deviation, or Addition to the BWROG Emergency Procedure Guideline, Rev.3 l coev.oet. Aco) EPG Guldeline/ Contingency: RPVCONTROL EPG Section: RC/P EPG Step: RC/P-4 EPG Statement: If the RHR shutdown cooling mode cannot be established and further cooldown is required, continue to q cool down using one or more of the systems used for depressurization. l EPG Basis: If shutdown cooling cannot be established, further RPV depressurization may be accomplished using any of the systems listed in Step RC/P-2. As RPV pressure decreases, it may be necessary to re-evaluate the most appropriate means of pressure reduction. Under certain conditions RPV pressure may be reduced to near zero without employing the shutdown cooling mode of RHR. PSTG Guidellne/ Contingency: RPVCONTROL PSTG Section: RC/P PSTG Step: RC/P-4 PSTG Statement: na PSTG Justification: OP 0109 - Plant Restoration - adequately addresses this concern. It is intended to be entered upon exit I from the OE. It instructs the operator to establish shutdown cooling if necessary, and provides additional direction thould the RHR shutdown cooling mode bo unavailable. j JDDA - 15 1
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JUSTIFICA N Justification for Deletion, Deviation, or Addition to the BWROG Ernergency Procedure Guideline, Rev.3 (DEV. DEL ADD) EPG Guideline / Contingency: FFVCONTROL EPG Section: RC/O EPG Step: n/a EPG Statement: If while executing the following steps:
. All control rods are inserted beyond position [06 (maximom suberitical banked rod withdrawal position)?, terminate boron injection and enter [ scram procedure].
. The reactor is shutdown and no boron has been injected into the RPV, enter [ scram procedure].
EPG Basis: By definition, the reactor is and will remain shutdown when all control rods are inurted to the Maximum Subcritical Banked Withdrawal Position (MSBWP). If it is concluced that the reactor is shutdown with no boron having been injected into the RPV, an exit to the scram procedure is appropriate even though al! all control rods are not inserted to the MSBWP. If subsequently the reactor returns to criticality as RPV depressurization and cooldown proceed, the steps of the RPV pressure control section of the RPV control guideline prevent further cooldown until the reactor is again shutdown through either control rod insertion or boron injection. PSTG Guideline / Contingency: RPVCONTROL PSTG Section: RC/O PSTG Step: n/a PSTG Statement: If while executing the following steps:
. All control rods are inserted to or beyond position 02, terminate boron injection and enter [ scram procedure).
PSTG Justifleation: As noted in the EPG basis above, the reactor will remain shutdown when all control rods are inserted to the Maximum Subcritical Banked Withdrawal Position (MSBWP). Therefore, it is appropriate to state "to or beyond [the MSBWP]". The statement " the reactor is shutdown and no boron has been injected into the RPV, enter [ scram procedure)" has been eliminated due to the uncertainy of the actual shutdown margin (the condition could require a greater degree, of knowledge than is possessed by the average operator), and the seriousness of the consequences of depressurization and cooldown without positive confirmation of j reactor shutdown. Additionally, the RC/O section contains the necessary instructions for insertion of f control rods with concurrent conditions of support system failure which should be tr.ilized by the j l operator as soon as possib;e folloeng as ATWS. j JDDA - 13.1 l n- _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ - -
i l l l l Justification for Deletion, Deviation, or Addition msmCA " l E. DEV to the BWROG Emergency Procedure Guideline, Rev.3 (DEV. DEL. ado) F' EPG Guidellne/ Contingency: RPVCONTROL EPG Section: RC/O EPG Step: RC/Q-1 EPG Statement; l [ Confirm or place the reactor mede switch in SHUTDOWN.] EPG Basis: The above step inserts a diverse and redur. dant reactor scram signal via the RPS logic. Positioning the reactor mode switch to SHUTDOWN momentarily opens contacts which trip the RPS logic in the sanie manner as sensor or sensor relay contacts. In a few plants this elso initiates closure of the MSIVs if main steam flow is above 40% rated. PSTG Guidellr a/ Contingency: RPVCONTROL PSTG Section:) RC/O PSTG Step: RC/Q 1 PSTG Stateme ((; Confirm or pla:'1 the reactor modo switch in SHUTDOWN or REFUEL when main steamline f!ow is < 0.5 Mlbs/hr per s .3amline. PSTG Justiffeation: 15e REFUEL position is given as an option should the operator wish to avoid inserting a redundant scram sic'al via the RPS logic, as well as initiating a 10 second timer whict, would prevent any manual rod mo' ion. With the mode switch in REFUEL the operator also has a redundant means of ascertaining control rods ce all fully inserted via the REFUEL MODE ONE ROD PERMISSIVE fight on CRP 9-5 panel. The conditional statement concerning main steamline flow is included to preclude MSIV isolation due to high steamline flow of 40% when the mode switch is not in RUN. j JDDA - 16
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JUSTIFICA N Justification for Deletion, Deviation, or Addition to the BWROG Emergency Procedure Guidellru, Rev.3 (DEV. DEL. ADD) i EPG Guidellne/ Contingency: RPVCONTROL EPG Section: RC/O EPG Step: RC/O-2 EPG Statement: If the main turbine generator is on line and the MSIVs are open, confirm or initiate recirculation flow runback to minimum. EPG Basis: An immediate and rapid power reduction may be effected by reducing reactor coolant recirculation flow rate, if the turbine trips, and reactor power exceeds the turbine bypass capacity, RPV pressure will increase until one or more SRVs open. Heatup of the suppression pool then begins and boron injection may ultimately be required. PSTG Guideline / Contingency: RPVCOtfrROL PSTG Section: RC/O PSTG Step: RC/O-2 PSTG Statement: . Confirm or initiate recirculation flow runback to minimum. PSTG Justifleation: Vermont Yankee has a turbine bypass capacity equivalent to 105% of rated power. Therefore it is not necessary to condition recirculation runback to minimum on the turbine generator being on line. Under these circumstances, whether or not the MSIVs are open is immaterial since runback of the recirculation flow (thereby decreasing reactor power) is the appropriate operator action. l l JDDA - 17 l J 1 _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ . _ n
JUSTIFICA N Justification for Deletion, Deviation, or Addition to the BWROG Emergency Procedure Guideline, Rev.3 (CEV. DEL ADO) EPG Guldeline/ Contingency: FFVCONITOL EPG Section: RC/O l EPG Step: RC/O-3 EPG Statement: If reactor power is above [3% (APRM downscale trip)) or cannot be determined, trip the recirculation pumps. EPG Basis: Tripping the recirculation pumps from high reactor power effects a prompt reduction in power. Even if boron injection is later required, 3D scale model tests have demonstrated that natural circulation flow provides adequate boron mixing and forced recirculation need not be maintained. PSTG Guideline / Contingency: RPVCONTROL PSTG Section: RC/O PSTG Step: RC/O-3 PSTG Statement: If reactor power is above [2% (APRM downscale trip)] or cannot be determined:
+ trip the recirculation pumps
. manually initiate ARl/RPT.
PSTG Justification: Manual initiation of ARl/RPT not only trips the recirculation pumps (RPT), but also inserts a redundant scram via the alternate rod insertion scram valves (ARI). I I JDDA - 1 1 0 D
JUSTIFICA Justification for -Deletion, Deviation, or Addition to the BWROG Emergency Procedure Guideline, Rev.3 (DEV. DEL. ADD) EPG Guideline / Contingency: FFVCOtRROL EPG Section: RC/O l EPG Step: RC/O 4 EPG Statement: If boron cannot be injected with SLC, inject boron into the RPV by one or more of the following alternate methods:
.CRD . RCIC
. HPCS -
Hydro pump
.RWCU
. Feedwater
. HPCI EPG Basis: 3 A list of one or more alternate methods for injecting boron irito the RPV is specified in this step to address potential nonavailability or malfunctioning of the SLC system. The list of systems that is specified should include at least one pump able to inject into the RPV at rated RPV pressure.
PSTG Guldeline/ Contingency: RPVCONTROL PSTG Section: RC/O lPSTG Step: RC/Q-4 PSTG Statement: If boron cannot be injected with SLC, inject boron into the RPV by one or more of the following alternate ! methods:
. Local firing of the Squib valve
.RWCU
.CRD 1
PSTO Justiffention: After assessing the various plant systems, shift staffing, probable time constraints, and equipment and supplies availability, it was decided to limit the alternate injection systems to two. Both are capable of injection to the RPV at rated RPV pressure and at flowrates equivalent to the SLC system. The local firing of the SLC explosive injection valves was added at a later date due to malfunctioning of these valves during system operational testing. JDDA - 19 (- - _ _ _ .- _ _ _ . . 9_.
Justification for Deletion, Deviation, or Addition JUSECA " E: DEV to the BWROG Emergency Procedure Guideline, Rev.3 1 (DEV. DEL. A00) j j EPG GuidelinelContInge 1cy: PRIMARY CONTAINMENT CONTROL EPG Section: Entry Conditions EPG Step: na EPG Statement:
. Suppression pool water level above (12 ft. 6 in. (maximum suppression pool water level LCO)}
l EPG Basis: A condition which is symptomatic of an emergency condition or conditions which, if not corrected, could degrade into an emergency. PSTG Guideline / Contingency: SUPPRESSION POOLCONTROL PSTG Section: Entry Conditions PSTG Step: na PSTG Statement:
- Suppression pool water volume above 70,000 cu. ft. (maximum suppression pool water volume LCO)
PSTG Justification: Vermont Yankee does not have an LCO pertaining to suppression pool level. Rather, a water volume is used (TS Section 3.7.A.1). JDDA - 20 _ _ - _ _ - _ _ _ - _ _ _ _ _ _ . . _ _ _ _ _ _ _ _ _ _ _ ._ .w n
JUS M CA N Justification for Deletion, Deviation, or Addition e: DEV to the BWROG Emergency Procedure Guideline, Rev.3 (DEV. DEL. ADD) EPG Guideline / Contingency: PRIMARY CONTAINMENT CONTROL EPG Section: Entry Conditions EPG Step: na EPG Statement:
. Suppression pool water level below [12 ft. 2 in. (minimum suppression pool water level LCO))
EPG Basis: A condition which is symptomatic of an emergency condition or conditions which, if not corrected, could degrade irito an emergency. PSTG Guideline / Contingency: SUPPRESSION POOLCONTROL PSTG Section: Entry Conditions PSTG Step: na PSTG Statement:
. Suppression pool water volume below 68,000 cu. ft. (minimum suppression pool water volume LCO)
PSTG Justifleation: Vermont Yankee does not have an LCO pertaining to suppression pool level. Rather, a water volume is used (TS Section 3.7.A.1). JDDA - 21 - _ _ _ _ - - _ _ _ _ - - - _ _ _ - _ _ _ _ - a a
Justification for Deletion, Deviation, or Addition NC " E: DEV 1 to the BWROG Emergency Procedure Guideline, Rev.3 (DEV. DEL. AcD) EPG GuldelinelContIngency: PRIMARY CONTAINMENT CONTROL EPG Section: Operator Actions EPG Step: na EPG Statement: Irrespective of the entry condition, execute [ Steps SP/T, DW/T, PC/P, and SP/L] concurrently. EPG Basis: Concurrent control of all four primary containment parameters is required when taking action to monitor and control any one. This is a natural result of the fact that, when isolated, the primary containment functions as a closed thermodynamic system, and all four primary containment parameters are directly interrelated. PSTG Guldeline/ Contingency: SUPPRESSION POOLCONTROL PSTG Section: Operator Actions PSTG Step: na PSTG Statement: Irrespective of the entry condition, execute [ Steps SP/T and SP/L] concurrently. PSTG Justification: The basis for the EPG statement is not entirely correct. The drywell and suppression chamber are to a great extent de-coupled by virtue of the primary containment design (i.e.: downcomers). In fact, when isolated, the RPV is as closely coupled to the suppression chamber as is the drywell (i.e.: SRV discharge lines). Therefore it is not correct to say that the primary containment functions as a closed thermo-dynamic system. That the drywell and suppression chamber are coupled is exhibited by the various steps in the guideline which requires a knowledge of one primary containment parameter when performing some action affecting the others. These relationships have not been disturbed. The greatest benefit derived by this division has been the narrowing of the field of required operator actions during that period of time when his attention may be required to be concentrated in some other area (i.e.: RPV control). l
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JUSTIFICA N Justification for Deletion, Deviation, or Addition to the BWROG Emergency Procedure Guideline, Rev.3 (DEV. DEL. ADD) EPG GuldelinelContingency: PRIMARY CONTAINMENT COfRROL EPG Section: S P/T EPG Step: SP/T-1 EPG Statement: Close all SORVs. I If any SORV cannot be closed [within 2 minutes (optional plant-specific time interval)], scram the reactor. EPG Basis: Any continiuous steam discharge through an open SRV constitutes a significant heat load to the suppression pool which may ultimately result in very high suppression pol temperatures. An attempt is therefore made to close all stuck open SRVs to terminate both the energy e.idition to the suppression pool and the loss of RPV coolant. If any SORV cannot be closed, the reactor is scrammed to minimize the total integrated heat energy available to be discharged to the suppression pool via the open SRV. PSTG Guideline / Contingency: SUPPRESSION POOLCONTROL PSTG Section: na PSTG Step: na PSTG Statement: na PSTG . justification: Since a stuck-open relief valve (SORV) cannot by definition be closed, this action has been deleted. Further, as the torus cooling function can be adequately handled by the Residual Heat Removal and Emergency Service Water systems, there is no need to immediately scram the reactor. [
Reference:
Memo, J.D. Candon to B.C. Slifer/M.J. Marian,
- Review of OP3105, Rev.2, ' Relief Valve Stuck Open Emergency Procedure', dated 8/30/84]
JDDA - 23
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Justification for Deletion, Deviation,- or Addition #** " E. DEV to the BWROG Emergency Procedure Guideline, Rev.3 (DEV.oEL. AD0) EPG Guideline / Contingency: PRIMARY CONTAINMENT CONTROL EPG Section: SP/T EPG Step: S P/T-3 EPG Statement: Before suppression pool temperature exceeds [110'F ( Boron Injection initiation Temperature)j, scram the reactor. , EPG Basis: Scramming the reactor before suppression pool temperature reaches the Boron Injection Initiation Temperature assures that, if possible, the reactor is shutdown by control rod insertion before the requirement for boron injection is reached. PSTG Guideline / Contingency: SUPPRESSION POOLCONTROL PSTG Section: SP/T PSTG Step: S P/T-2 PSTG Statement: Before suppression pool temperature exceeds 110'F (Boron injection initiation Temperature):
- 1. Runback recirculation flow to minimum
- 2. Transfer electrical loads to the Startup Transformers
- 3. Manually scram the reactor; enter OE3100 (scram procedure) and execute it concurrently with this procedure.
PSTG Justifleation: The operator is directed to first establish plant conditions which will help mitigate the effects of the transient resulting from the manual scram. Additionally, he is directed to execute the scram procedure concurrently to ensure that plant systems are aligned appropriately for the changed plant operating condition (i.e.: all rods inserted, IRMs and SRMs driven into the core, etc.), JDDA - 24 I - _ _ - _ _ _ - _ _ _ - _ _ _ _ _ _ _ _ _ .c _ _ _ _ _ _ _ n
JUSTIFICA N Justification for Deletion, Deviation, or Addition to the BWROG Emergency Procedure Guideline, Rev.3 (DEV. DEL. ADD) EPG GuldellnelContingency: PRIMARY CONTAINMENT CONTROL i EPG Section: S P/T EPG Step: na EPG Statement: na EPG Basis: na PSTG Guidellne/ Contingency: SUPPRESSION POOLCONTROL PSTG Section: S P/T PSTG Step: S P/T-3 Ef'{G 9tatement: If suppression pool temperature is above 120*F (TS suppression pool temperature LCO) and the RPV is isolated from the main condenser, commence depressurizing the RPV at normal cooldown rates to < 200 psig. Ef>TG Justiffeation: Vermont Yankee's Technical Specifications states that experimental data indicate that excessive steam condensing loads can be avoided if the peak temperature of the suppression pool is maintained below 160*F during any period of relief valve operation with sonic conditions at the discharge exit. Specifications have been placed on the envelope of reactor operating cond"..ons so that the reactor can be depressurized in a timely manner to avoid the regime of potentially hd suppression chamber loadings. I [
Reference:
TS Section 3.7.A. Bases] JDDA - 25 _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ e o 1
L , 1 l JUSTlFICA Justification for Deletion, Deviation, or Addition to the BWROG Emergency Procedure Guideline, Rev.3 (DEV. DEL. ADD) EPG Guideline / Contingency: PRIMARY CONTAINMENT CONTROL EPG Section: SP/L EPG Step: SP/L-1 EPG Statement: (Reference to Caution #8 " Observe NPSH requirements for pumps taking suction from the suppression pool".) EPG Bastsl The applicability of Caution #8 is identified at this step because of the direct effect of low suppression pool water level has on pump NPSH. PSTG Guideline / Contingency: SUPPRESSION POOLCONTROL PSTG Section: SP/L PSTG Step: SP/L-1 PSTG Statement: na PSTG Justification: The derivation of the curve associated with Caution #8 (i.e.: Required NPSH Curve) is based on there being the minimum water level in the suppression pool to ensure submergence of the suction strainers for the various systems taking a suction on the suppression pool. Therefore, the curve may be considered independent of the suppression pool water level and does not apply to this step. [See the justification for the DEVIATION from EPG Caution #8 for further information.) JDDA - 26
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i l l-1 mmCA N Justification for Deletion, Deviation, or Addition e. DEL to the BWROG Emergency Procedure Guideline, Rev.3 (DEV. DEL. ADD)
]
EPG GuldellnelContIngency: PRIMARY CONTAINMENT CONTROL i l' EPG Section: SP/L EPG Step: S P/ L-1 EPG Statement: (Reference to Caution #9 *lf signals of high suppression pool water level [12 ft. 7 in. (high level suction interlock)] or low condensate storage tank water level [0 in. (Iow level suction interlock)] occur, confirm automatic transfer of or manually transfer HPCI, HPCS, and RCIC suction from the condensate storage tank to the suppression pool".) EPG Basis: The applicability of Caution #9 is identified at this step beca se selection of the suction source for HPCl, HPCS, and RCIC is determined directly by suppression pool water level. i PSTG Guldellne/ Contingency: SUPPRESSON POOLCONTROL PSTG Section: SP/L PSTG Step: SP/L 1 PSTG Statement: na PSTG Justifleation: At Vermont Yankee, the selection of the suction source for HPCI and RCIC is no Icnger determined by suppression pool water level. This automatic transfer logic has been removed. Therefore this caution does not apply for VY [See the justification for DEVIATION from EPG Caution #9 for further information.] JDDA - 27
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Justification for Deletion, Deviation, or Addition SS M CA " E. ADD to the BWROG Emergency Procedure Guldeline, Rev.3 (DEV. DEL ADD) EPG Guideline / Contingency: PRIMARY CONTAINMENT CONTROL EPG Section: SP/L EPG Step: n/a l EPG Statement: n/a I 4 EPG Basis: n/a l l PSTG Guideline / Contingency: SUPPRESSION POOLCONTROL PSTG Section: SP/L PSTG Step: S P/L-1 PSTG Statement: CURVE: Drywell/ Torus AP (psid) vs. Indicated Torus Water Level (ft) PSTG Justifleation: During normal plant operation, Vermont Yankee maintains an inerted containment with a pressure differential between the drywell and suppression chamber. The maintenance of a drywell - suppression chamber differential pressure of 1.7 psid and a suppression chamber water level corresponding to a downcomer submergence range of 4.29 to 4.54 ft. assures the integrity of the suppression chamber when subjected to post LOCA suppression pool hydrodynamic forces (T.S. Bases, section 3.7.A). However, this AP, which will vary with operational conditions, results in the displacement of water from the downcomers into the suppression chamber proper. Therefore, suppression pool water volume , will depend upon both water level and AP. This curve is provided as an operator aide in determining I actual water volume. i JDDA - 28 _ _ _ _ - _ _ _ _ _ _ _ . . _ _ - _ _ _ . _ _ A. n
l msmCA N Justification for Deletion, Deviation, or Addition e. DEL to the BWROG Emergency Procedure Guideline, Rev.3 (DEV.0EL ADO) l l EPG Guldeline/ Contingency: PRIMARY CONTAINMENT CONTROL EPG Section: SP/L EPG Step: SP/L 1 l EPG Statement: If SPMS has been initiated, maintain suppression pool water level between [23 ft 9 in. (SPMS initiation setpoint plus suppression pool water level increase which results from SPMS operation)] and [19 ft.11 in. (minimum suppression pool water level LCO)]. ( i EPG Basis: Plants with Mark lli containments may add water to the suppression pool using the suppression pool makeup system (SPMS). ; l ( 1 1 PSTG Guldeline/ Contingency: SUPPRESSION POOLCONTROL PSTG Section: SP/L PSTG Step: SP/L-1 PSTG Statement: n/a PSTG Justifleation: Vermont Yankee has a Mark I containment and is not equiped with a SPMS. JDDA - 29
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1 i JUSTIFICA N Justification for Deletion, Deviation, or Addition to the BWROG Emergency Procedure Guideline, Rev.3 (DEv.CdL, ADD) EPG GuldelinelContingency: PRIMARY CONTAINMENT CONTROL EPG Section: SP/L EPG Step: SP/L 2 EPG Statement: Maintain suppression pool water level above the Heat Capacity Level Limit. EPG Basis: The energy balance used in calculating the Heat Capacity Temperature Limit (HCTL) assumes a suppression pool water level at or above the minimum LCO. If a lower suppression pool water level exists, the heat capacity of the suppression pool is reduced. The Heat Capacity Level Limit adjusts the HCTL for suppression pooi water levels below the minimum. PSTG Guideline / Contingency: SUPPRESSION POOLCONTROL PSTG Section: SP/L PSTG Step: SP/L 2 PSTG Statement: Maintain suppression pool water level above the Heat Capacity Level Limit using any of the following system:
.HPCI
- RCIC
. Core Spray
.RHRSW PSTG Justification:
The basis for maintaining the suppression pool level remains the same as above EPG basis. However, a list of systems has been provided for performing this action as an aide to the operator. JDDA - 30 g e
i JUSTIFICA N Justification for Deletion, Deviation,- or Addition- 3 to the BWROG Emergency Procedure Guideline, Rev.3 . l (DEV. DEL. ADD) EPG GuldelinelContIngency: PRIMARY CONTAINMENT CONTROL EPG Section: SP/L -l EPG Step: S P/L-2 EPG Statement: n/a i EP_9 Basis: n/a j l I PSTG Guideline / Contingency: SUPPRESSK)N POOLCONTROL f PSTG Section: SP/L lPSTG Step: SP/L-2 PSTG Statement: Reference to Caution #18 "If continuous operation of any RHR pump is required to assure adequate core cooling, do not divert all RHR pumps from the LPCI mode." l 1 PSTG Justificatlen: This was added since use of RHRSW to makeup water to the suppression pool in order to maintain level above the HCLL would require use of the RHR system discharge piping entering the suppression pool. JDDA - 31 - _ _ _ _ _ _ _ _ _ _ _ - _ _ _ _ _ _ - _ _ _ _ - _ _ . _A . a.
Justification for Deletion, Deviation, or Addition MC " E: DEV to the BWROG Emergency Procedure Guideline, Rev.3 (DEV. DEL ADO) EPG Guldeline/ Contingency: PRIMARY CONTAINMENT CONTROL EPG Section: SP/L EPG Step: SP/L-2 EPG Statement: If suppression pool water level cannot be rnaintained above the Heat Capacity Level Limit, EMERGENCY RPV DEPRESSURIZATION IS REQUIRED; enter (procedure developed from the RPV Control Guideling] at [ Step RC-1] and execute it concurrently with this procodure. EPG Basis: Depressurization of the RPV is manually initiated before suppression pool water level decreases below the HCLL. The consequences of not depressurizing the RPV under these conditions include overpressurization of the suppression chamber due to steam flow form the drywell and containment failure due to unstable steam condensation. The instruction to enter the RPV Control Guideline provides the mechanism by which Contingency #2 (Emergency RPV Depressurization) is reached. PSTG Guideline / Contingency: SUPPRESSION POOLCONTROL PSTG Section: SP/L PSTG Step: SP/L 2.1 PSTG Statement: If suppression pool water level cannot be maintained above the Heat Capacity Level Limit, EMERGENCY RPV DEPRESSURIZATION IS REQUIRED:
- 1. Runback recirculation flow to minimum
- 2. Transfer electrical loads to the Startup Transformers
- 3. Manually scram the reactor; enter OE 3100 (scram procedure) and execute it concurrently with this procedure.
- 4. Enter (procedure developed from Contingency #2] and execute it concurrently with this procedure.
ES,TG Justifleation; Before initiating depressurization, the reactor is scramed to limit the heat load on the containment. The operator is directed to first establish plant conditions which will help mitigate the effects of the transient resulting from the manual scram. Additionally, he is directed to execute the scram procedure concurrently to ensure that plant systems are aligned appropriately for the changed plant operating condition (i.e.: all rods inserted, IRMs and SRMs driven into the core, etc.). In addition, rather than entor Contingency #2 by way of the RPV Control Guideline, the operator is required to proceed to Contingency #2 directly. Concurrent control of the three interrelated RPV parameters (RPV water level, RPV pressure, and RPV reactor power) are the normal functions of the operating crew, and are defined in both normal as well as emergency operating procedures. JDDA - 32
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JUSTIFICA N Justification for Deletion, Deviation, or Addition to the BWROG Emergency Procedure Guideline, Rev.3 (DEV. DEL. ADD) EPG _ Guideline / Contingency: PRIMARY CONTAINMENT CONTROL EPG Section: SP/L EPG Step: SP/L-2 l EPG Statement: n/a EPG Basis: n/a PSTG Guldeline/ Contingency: SUPPRESSION POOLCONTROL PSTG Section: SP/L lPSTG Step: SP/L-2.2 PSTG Statement: If suppression pool water level cannot be maintained above 8.6 ft. (RCIC turbine exhaust):
- 1. Runback recirculation flow to minimum.
- 2. Transfer electrical loads to the Startup Transformers.
- 3. Manually scram the reactor; enter OE 3100 (scram procedure) and execute it concurrently with this procedure.
- 4. Initiate suppression pool sprays.
J PSTG Justification: If the operator was unsuccessful in maintaining suppression pool water level above the RCIC turbine ) exhaust elevation, which was chosen being the highest elevation of those systems discharging energy to containment (i.e.: HPCI, RCIC and SRVs), he is directed to scram the reactor (if not already shutdown) to limit the heat input to containment. In addition, the suppression pool sprays are initiated in anticipation of the need to condense steam discharged to the suppression chamber which is bypassing the suppression pool due to low water level. JDDA - 33 _ _ _ _ - _ _ - _ _ _ _ _ _ _ _ _ _ _ _ _ - _ _ _ _ _ _ _ _ . ___ A Q l
msmCA
. Justification for Deletion, Deviation, or Addition E1 ADD to the BWROG Emergency Procedure Guideline, Rev.3 (DEv, DEL, ADD)
EPG Guideline / Contingency: PRIMARY CONTAINMENT CONTROL EPG Section: SP/L EPG Step: S P/L-2 l EPG Statement: n/a EPG Basis: n/a PSTG Guideline / Contingency: SUPPRESS 10N POOLCONTROL PSTG Section: SP/L lPSTG Step: S P/L-2.3 PSTG Sintement: If suppression pool water level cannot be maintained above 6.5 ft. (highest elevation of ECCS suction within the suppression pool) or the combination of suppression chamber airspace temperature and suppression pool water level cannot be maintained below the Required NPSH Curve, then line-up for injection those systems which take a suction external to the primary containment. PSTG Justiflentlen: If the operator was unsuccessful in maintaining suppression pool water level and airspace temperature within the limits described above, loss of ECCS taking suction from the suppression pool is likely to occur due to the available NPSH being less than the required NPSH for the pumps employed in these systems. He is therefore directed to prepare injection systems which are not dependent on the suppression pool. JDDA - 34 s ,
JUSTIFICA N Justification for Deletion, Deviation, or Addition to the BWROG Emergency Procedure Guideline, Rev.3 (DEV. DEL. ADD) EPG Guldelinelcontingency: PRIMARY CONTAINMENT CONTROL EPG Section: SP/L EPG Stept SP/L-3 l l EPG Statement: Execute [ Steps SP/L-3.1 and SP/L-3.2) concurrently. l EPG Basis: The sequence in which the high suppression pool water level conditions addressed in Steps SP/L-3.1 and SP/L-3.2 may occur varies for different events. The event-independent structure and organization of the EPGs thus requires that both these conditions be monitored concurrently. PSTG Guideline / Contingency: SUPPRESSION POOLCONTROL PSTG Section: SP/L PSTG Step: SP/L-3 PSTG Statement: n/a PSTG Justiffention: The EPG basis is generic in nr.ture and may not be true for all BWRs. This is the case for Vermont Yankee. If the operator is capable of maintaining the suppression pool water level below the Suppression Poci Load Limit (step SP/L-0.1), he would then proceed in attempts to maintain water level below the elevation of the drywell/wrtwell vacuum breaker vent line (step SP/L 3.2). This structure was chosen since it leads from a less restrictive to a more restrictive limit on suppression pooi water level. JDDA - 35
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i i l Justification for Deletion,- Deviation, or Addition msmCA N e: DEV to the BWROG Emergency Procedure Guideline, Rev.3 ; coev.oet. Acos j EPG Guldellne/ Contingency: PRIMARY CONTAINMENT CONTROL EPG Section: SP/L EPG Glop: S P/L-3.1 EPG Statement: Maintain suppression pool water level below the Suppression Pool Load Limit. EPG Basis: The Suppression Pool Load Limit (SPLL) limits suppression pool water level as a function of RPV pressure so that the yield stress of the most limiting submerged structural component in the suppression pool will not be exceeded during an SRV actuation. PSTG Guldeline/ Contingency: SUPPRESSION POOL COfRROL PSTG Section: SP/L PSTG Step: SP/L 3.1 PSTG Statement: Maintain suppression pool water level below the Suppression Pool Load Limit using any of the following systems:
.RHR
.HPCI
. RCIC PSTG Justification:
The basis for maintaining the suppression pool level below the SPLL rema'ns the same as above EPG basis. However, a list of systems has been provided for performing this action as an aide to the operator. l l JDDA - 36 1
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l l JUSTIFICA N Justification for Deletion, Deviation, or Addition to the BWROG Ernergency Procedure Guideline, Rev.3 (DEV. DEL, ADO) EPG Guldeline/ Contingency: PRIMARY CONTAINMENT CONTROL EPG Section: SP/L EPG Step: SP/L 3.1 EPG Statement: n/a EEG Basis: n/a
/
PSTG Guldeline/ Contingency: SUPPRESSON POOL CONTROL PSTG Section: SP/L PSTG Step: S P/L-3.1 PSTG Statement: Reference to Caution #31 " Control Room indication of the following parameters are subject to instrument error:
- Drywell tempererature +/- 10 *F Reactor pressure +/- 40 psi" PSTG Justifiestion:
This caution was added since RPV pressure is one of the parameters that the operator is directed to control per the Suppression Pool Load Limit curve (i.e.: Torus Water Level vs. RPV pressure) in Step SP/L-3.1. Since the operator is required to stay below the SPLL curve, it was deemed necessary that the magnitude of instrument inaccuracy for post accident conditions be included within the procedure. (reference: Memo, M.E. Palionis to D.E. LaBarge, " Addition of Caution to Emergency Operating Procedures, dated 6/20/86)
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EDDA - 37 o .0
JUSTIFICA Justification for Deletion, Deviation, or Addition to the BWROG Emergency Procedure Guideline, Rev.3 (DEV. DEL. ADD) EPG GuldelinelContIngency: PRIMARY CONTAINMENT CONTROL EPG Section: SP/L EPG Step: S P/ L-3.1 EPG Statement: If suppression pool water level and RPV pressure cannot be restored and maintained below the Suppression Pool Load Limit, EMERGENCY RPV DEPRESSURIZATION IS REQUIRED; enter (procedure developed from the RPV Control Guideline) at (Step RC-1] and execute it concurrently with this procedure. EPG Basis: Once it is concluded that suppression pool water level and RPV pressure cannot be restored and maintained below the SPLL, depressurization of the RPV is manually initiated while the water level in the suppression pool is sufficiently low to safely accomodate the dynamic loading which results from the blowdown. The instruction to enter the RPV Control Guideline provides the mechanism by which Contingency #2 (Emergency RPV Depressurization) is reached. PSTG Guidellne/ Contingency: SUPPRESSION POOL CONTROL PSTG Section: SP/L PSTG Step: S P/L-3.1 PSTG Statement: If suppression pool water level and RPV pressure cannot be restored and maintained below the Suppression Pool Load Limit, EMERGENCY RPV DEPRESSURIZATION IS REQUIRED:
- 1. Runback recirculation flow to minimum
- 2. Transfer electrical loads to the Startup Transformers
- 3. Manually scram the reactor; enter OE 3100 (scram procedure) and execute it concurrently with this procedure.
- 4. Enter [ procedure developed from Contingency #2] and execute it concurrently with this procedure.
PSTG Justifleation: The bases for depressurization is not changed from the above EPG bases. Before initiating depressurization, the reactor is scramed to limit the heat load on the containment. The operator is directed to first establish plant conditions which will help mitigate the effects of the transient resulting from the manual scram. Additionally, he is directed to execute the scram procedure concurrently to ensure that plant systems are aligned appropriately for the changed plant operating condition (i.e.: all rods inserted, IRMs and SRMs driven into the core, etc.). In addition, rather than enter Contingency #2 by way of the RPV Control Guideline, the operator is required to proceed to Contingency #2 directly. Concurrent control of the thres interrelated RPV parameters (RPV water level, RPV pressure, and RPV reactor power) are the normal functions of the operating crew, and are defined in both normal as well as emergency operating procedures. f JDDA - 38
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JUSTIFICA N Justification for Deletion, Deviation, or Addition to the BWROG Emergency Procedure Guideline, Rev.3 (DEV. DEL. ADD) EPG Guideline / Contingency: PRIMARY COWAINMENT CONTROL EPG Section: SP/L EPG Step: S P/L-3.2 l EPG Statement: Before suppression pool water level reaches [17 ft. 2 in. (Maximum Primary Containment Water Level Limit or elevation of bottom of Mark i internal suppression chamber to drywell vacuum breakers less vacuum breaker opening pressure in feet of water, whichever is lower)) but only if adequate core cooling is assured, terminate injection into the RPV from sources external to the primary containment except boron injection systems and CRD. EPG Basis: The internal suppression chamber to drywell vacuum breakers in the Mark I containment cannot be relied upon to adequately control suppression chamber to-drywell differential pressure if water is present on either side of these devices. Primary containment water level above either the elevation at which the hydrostatic head equals the yield stress of the containment at the limiting location or the elevation of the primary containment vent defines the MPCWLL. Therefore if possible, it is appropriate to establish a recirculation mode of cure cooling within the primary containment prior to suppression pool water level exceeding either of these conditions. PSTG Guideline / Contingency: SUPPRESSION POOLCONTROL PSTG Section: SP/L PSTG Step: SP/L-3.2 PSTG Statement: n/a PSTG Justification: Significant increase of primary containment water level is an indication of breach of the RPV inside primary containment. The most reliable means of assuring adequate core cooling is by flooding the RPV. For events when significant breaks occur in the RPV, resulting in increasing primary containment water level which cannot be controlled via drain or pump down systems, the only alternative is to flood the primary containment. This is recognized in Vermont Yankee's FSAR, Section 5.2.2: Primary Containment System - Safety Design Bases", design bases 4. Therefore, the injection sources external to the primary containment would continue to be used unless otherwise restricted per the Suppression Pool Load Limit (see step SP/L-3.1) or unless the Maximum Primary Containment Water Level Limit is reached (see step SP/L-3.2). JDDA - 39 _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ s o
1 JUSTIFICA N l Justification for Deletion, Deviation, or . Addition to the BWROG Emergency Procedure Guideline, Rev.3 1 EPG Guideline / Contingency: PRIMARY CONTAINMENT CObfTROL EPG Section: S P/L EPG Step: S P/L-3. 2.1 EPG Statement: When suppression pool water level reaches [17 ft. 2 in. (elevation of bottom of Mark I internal suppression chamber to drywell vacuum breakers less vacuum breaker opening pressure in feet of water)] but only if [ suppression chamber temperature and drywell pressure are below the Drywell Initiation Pressure Limit], [ shut down recirculation pumps and drywell cicling fans and) initiate drywell sprays [ restricting flow rate to less than 720 gpm (Maximum Drywell Spray Fiv.y Rate Limit)]. EPG Basis: The internal suppression chamber to drywell vacuum breakers in the Mark I containment cannot be relied upon to adequately control suppression chamber to-drywell differential pressure if water is present on either side of these devices. Spraying the drywell results in condensation of steam and depressurization of the drywell, under which conditions the vacuum breakers will open and permit noncondensibles to return to the drywell. Thus, before these vacuum breakers become inoperable, the drywell is sprayed so that they can perform their intended functions. PSTG Guldeline/ Contingency: SUPPRESSION POOLCONTROL PSTG Section: SP/L PSTG Step: S P/L-3.2 PSTG Statement: When suppression pool water level reaches 22.4 ft. (elevation difference between the bottom of the suppression chamber and wetwell-to-drywell vacuum breakers' vent line) but only if suppression chamber temperature and drywell pressure are below the Drywell Spray initiation Pressure Limit:
- 1. Shutdown recirculation pumps and drywell RRUs
- 2. If suppression pool water level exceeds 22.4 ft., continue to operate drywell sprays i
PSTG Justifleetion: Vermont Yankee's primary containment is a Mark i type design, but employs external suppression chamber to drywell vacuum breakers. Since the elevation difference between the vent line leading from the suppression chamber and the top invert of the suppression chamber is four feet, there is a potential for noncondensibles to accumulate. By spraying the drywell, and assuming a pressure differential exists between the drywell and suppression chamber, these noncondensibles can bo vented back to the drywell as described in the above EPG basis. Note also that the operator is directed to continue spray operation if water level exceeds the vent elevation. This is in accordance with EPG step SP/L-3.2.2. JDDA - 40
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JUSTIFICA N Jp:,tification for Deletion, Deviation, or Addition to the BNROG F.nergency Procedure Guideline, Rev.3 (DEV. DEL. A00) m _m-EPG GuldelinelContingency: PRIMARY CONTAINMENT CONTROL EPG Section: Entry Conditions EPG Step: n/a l EPG Statement: Drywell temperature above [135 'F (drywell temperature LCO or maximum normal operating temperature LCO)] EPG Basis: The value for the entry condition was chosen to be simple, unambiguous, readily identifiable, operationally significant, and familiar to plant operators. It was also chosen to provide advance warning of potential emergency conditions, allowing operator action to be taken where such action may be successful in preventing otherwise more severe consequences. 1 i i
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PSTG Guideline / Contingency: DRYWELLCOfffROL PSTG Section: Entry Conditions PSTG Step: n/a PSTG Statement: Drywell temperature above 160 'F (drywell maximum normal operating temperature assumed for EO analysis) l PSTG Justification: VY does not have a drywell temperature LCO. However, Vermont Yankee's Equipment Qualification (EO) Program assumed a maximum normal operating temperature of 160 'F in their analysis when l determining the equipment qualification requirements for safety related equipment located in the drywell (i.e.: MSIV and SRV solenoids). Therefore, choice of this value provides both advance warning l to the plant operators, and has operational significance in terms of equipment qualification. I JDDA - 41 3 ___q_ n }
JUNCA Justification for Deletion, Deviation, or Addition E DEV to the BWROG Emergency Procedure Guideline, Rev.3 (DEV. DEL. ADD) EPG GuldelinelContIngency: PRIMARY CONTAINMENT CONTROL EPG Section: Operator Actions EPG Step: n/a l EPG Statement: Irrespective of the entry condition, execute [ Steps SP/T, DW/T, PC/P, and SP/L] concurrently. EPG Basis: Concurrent control of all four primary containment parameters is required when taking action to monitor and control any one. This is a natural result of the fact that, when isolated, the primary containment functions as a closed thermodynamic system, and all four primary containment parameters are directly interrelated. PSTG Guideline / Contingency: DRYWELLCONTROL PSTG Section: Operator Actions PSTG Step: n/a PSTG Statement: 1 Irrespective of the entry condition, execute [ Steps DW/T and PC/P] concurrently. I PSTG Justification: The basis for the EPG statement is not entirely correct. The drywell and suppression chamber are to a great extent de-coupled by virtue of the primary containment design (!.e.: downcomers). In fact, when isolated, the RPV is as closely coupled to the suppression chamber as is the drywell (i.e.: SRV discharge ; lines). Therefore it is not correct to say that the primary containment functions as a closed thermo- l dynamic system. That the drywell and suppression chamber are coupled is exhibited by the various steps in the guideline which requires a knowledge of one primary containment parameter when performing some action affecting the others. These relationships have not been disturbed. The greatest benefit derived by this division has been the narrowing of the field of required operator actions during that period of tiine when his attention may be required to be concentrated in some other area (i.e.: RPV control). JDDA - 42 _ _ _ _ _ _ . _ _ _ _ _ . _ _ _ _ _ _ _ _ _ 1 _ _ _ . _ t.
l l l Justification for Deletion, Deviation, or Addition msmc " E: DEV to the BWROG Emergency Procedure Guideline, Rev.3 (DEV. DEL. ADD) EPG Guideline / Contingency: PRIMARY CONTAINMENT CONTROL EPG Section: DW/T EPG Step: DW/T-1 EPG Statement: When drywell temperature exceeds [135 "F (drywell temperature LCO or maximum normal operating temperature, whichever is higher)], operate available drywell cooling. l EPG Basis: System and general plant operating procedures typically provide instructions for controlling and maintaining drywell temperature during routine plant operations, both shutdown and at power. If drywell temperature increases above the greater of the maximum normal operating drywell temperature or the drywell temperature LCO, Step DW/T-1 provides a smooth transition from normal operating procedures to emergency operating procedures, and assures that the normal method of drywell temperature control has been placed into operation in advance of employing more complex actions to terminate increasing drywell temperature. PSTG Guideline / Contingency: DRYWELLCOtRROL PSTG Section: DW/T PSTG Step: DW/T-1 PSTG Statement: When drywell atmospheric temperature exceeds 160 *F (drywell maximum normal operating temperature assumed for EO analysis), operate available drywell cooling. 1 PSTG Justifiestion: The basis remalns the same as for the EPG step. However, " atmospheric' was added as further clarification to the operator. JDDA - 43
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l JUSTIFICA N Justificatlan for Deletion, Deviation, or Addition to the BWROG Emergency Procedure Guideline, Rev.3 (DEV. DEL. ADD) EPG Guideline / Contingency: PRIMARY CONTAINMENT CONTROL EPG Section: DW/T EPG Step: DW/T-2 EEG Statement: If drywell temperature [near the cold reference leg instrument vertical runs] reaches the RPV Saturation Temperature, RPV FLOODING IS REQUIRED; enter [orocedure developed from the RPV Control Guideline] at (Step RC-1] and execute it concurrently with this procedure. I EEQ Basis: If the reference leg water temperature reaches saturation the reference leg column of water begins to boil and the reference leg water inventory is reduced. Under prolonged high temperature conditions, actuai RPV water level may have decreased to below the top of active fuel while indicated RPV water level remains well above it. Occurance of this condition therefore requires that the RPV be flooded in order to assure adequate core cooling. The instruction to enter the RPV Control Guide'ine provides the mechanism by which Contingency #6 (RPV Flooding) is reached. PSTG Guideline / Contingency: DRYWELLCONTROL PSTG Section: DW/T PSTG Step: DW/T-2 PSTG Statement: If drywell temperature [near the cold reference leg instrument vertical runs] reaches the RPV Saturation Temperature, RPV FLOODING IS REQUIRED:
- 1. Runback recircu'ation flow to minimum.
- 2. Transfer electrical loads to the Startup Transformers.
- 3. Manually scram the reactor; enter OE 3100 (scram procedure) and exeute it cor :urrently with this procedure.
- 4. Enter (procedure developed from Contingency #2] and execute it concurrently with this procedure.
PSTG Justifiestion: The RPV is first depressurized since low pressure, high volume systems are available and are most likely required, given the initiating condition. Before initiating depressurization, the reactor is scramed to limit the heat load on the containment. The operator is directed to first establish plant conditions which will help mitigate the effects of the transient resulting from the manual scrar". Additionally, he is directed to execute the scram procedure concurrently n ensure that plant systems are aligned appropriately for the changed plant operating conditioi :n addition, rather than enter Contingency #6 by way of the RPV Controi Guideline, the operator is required to proceed to Contingency #2. Concurrent control of the three interrelated RPV parameters (RPV water level RPV pressure, and RPV reactor power) are the normal functions of the operating crew, and are defined in both normal as well as emergency operating procedures. Contingency #6 is entered via Contingency #2. JDDA - 44 s a _ l
WSMCA " Justification for Deletion, Deviation, or Addition ADD E. to the BWROG Emergency Procedure Guideline, Rev.3 (DEV, DEL. ADD) EPG GuldelinelContIngency: PRIMARY CONTAINMENT CONTROL EPG Section: DW/T EPG Step: n/a l EPG Statement: n/a l l EPG Besis: n/a PSTG Guldeline/ Contingency: DRYWELLCONTROL PSTG Section: DW/T PSTG Step: DW/T-3 PSTG Statement: If drywell temperature cannot be stabilized below 280 'F (drywell design temperature) manually scram the reactor; enter OE 3100 (scram procedure) and execute it concurrently with this procedure. PSTG Justifleation: Should the drywell temperature attain the drywell design temperature without the reactor being shutdown, it is prudent to scram the reactor. This will limit the amount of energy available within the system that is the cause for the rise in temperature, and will lessen the demand on the operators' attention. JDDA - 45 - _ - ________ _ _ _ _ _ _ _ _ - _ _ s a
msmC N Justification for Deletion, Deviation, or Addition e: DEV to the BWROG Emergency Procedure Guideline, Rev.3 (DEV. DEL ADD) EPG Guldellne/ Contingency: PRIMARY COffTAINMENT CONTROL EPG Section: DW/T EPG Step: DW/T-3 EPG Statement: Before drywell temperature reaches [340 *F (maximum temperature at which ADS qualified or drywell design temperature, whichever is lower)) but only if [ suppression chamber temperature and drywell temperature pressure are below the Dnwell Spray initiation Pressure Limit), [ shutdown recirculation pumps and drywell cooling fans and) initiate drywell sprays [ restricting flow rate to less than 720 gpm (Maximum Drywell Spray Flow Rate Limit)]. EPG Basis: If available drywell cooling is unable to terminate increasing drywell temperature before equipment qualification limits or structural design limits are exceeded, drywell spray is initiated to effect the required drywell temperature reduction. Spray initiation is, however, conditioned upon the status of drywell pressure and suppression chamber temperature as defined by the Drywell Spray In taition Pressure Limit. PSTG Guldeline/ Contingency: DRYWELLCONTROL PSTG Section: DW/T PSTG Step: DW/T-4 PSTG Statement: If drywell temperature cannot be stabilized below 280 'F (drywell design temperature) but nnly if suppression chamber airspace temperature and drywell temperature pressure are below the Drywell Spray Initiation Pressure Limit:
- 1. Shutdown recirculation pumps and RRUs.
- 2. Spray the drywell with either of the following systems:
.RHR Fire System PSTG Justifiestfon:
l l The operators require a more definitive limit than "before drywell temperature reaches.. *. It was also recognized that some short delay may result in exceeding the temperature limit for a short period of time prior to the available drywell cooling turned the trcnd in drywell temperature. Therefore the wording "if drywell temperature cannot be stabilized..
- Since the design limit is based on drywell shell temperature, and not on atmospheric temperature, this is jucged to be conservative for the short duration envisioned.
In addition, an alternate supply of water for drywall spray is provided. This was added as a result of the Vermont Yankee Containment Safety Study, and provides a means of cooling the drywell for events such as Station Blackout. JDDA 46 1 i
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JUSTIFICA N Justification for Deletion, Deviation, or Acution to the BWROG Emergency Procedure Guideline, Rev.3 (DEV.0EL ADD) l EPG Guideline / Contingency: PRIMARY CONTAINMENT CONTROL EPG Section: DW/T EPG Step: DW/T-3 EPG Statement: n/a EPG Basis: n/a PSTG Guldeline/ Contingency: DRYWELLCONTROL PSTG Section: DW/T PSTG Step: DW/T-4 PSTG Statement: Reference to Caution #31 " Control Room indication of the following parameters are subject to instrument error:
. Drywell tempererature +/ 10 *F
. Reactor pressure +/- 40 psi"
[STG Justification: This caution was added since suppression chamber airspace temperature is one of the parameters that the operator is directed to control per the Drywell Spray Initiation Pressure Limit. Since the operator is required to stay below the DWSIPL curve, it was deemed necessary that the magnitude of instrument inaccuracy for p6st-accident conditions be included within the procedure. (reference: Memo, M.E. Palionis to D.E. LaBarge, " Addition of Caution to Emergency Operating Procedures, dated 6/20/86) JDDA - 47 _ _ _ _ _ _ _ _ _ _ _ - 9 r;
1 l l 1 i msmCA N Justification 'for Deletion, Deviation, or Addition a: ADD to the BWROG Emergency Procedure Guideline, Rev.3 (DEV. DEL. ADD) EPG Guideline / Contingency: PRIMARY CONTAINMENT CONTROL EPG Section: DW/T EPG Step: DW/T-3 EPG Statement: n/a l l l l l EPG Basis: n/a PSTG Guideline / Contingency: DRYWEU.COMROL PSTG Section: DW/T PSTG Step: DW/T-4 PSTG Statement: Reference to Caution #23 "Do not initiate drywell sprays if torus water levei is above 22.4 feet." PSTG Justification: Inability to assure primary containment vacuum breaker operation precludes subsequent initiation of drywell sprays as indicated by Caution #23. This was used as the basis for applying this caution to EPG step SP/L-3.2, and is felt to be equally applicable whenever drywell sprays are initiated. JDDA - 48 _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ . - _ _ _ _ _ _ _ __s.- o
JUSECA N Justification for Deletion, Deviation, or Addition ADD e: to the BWROG Emergency Procedure Guideline, Rev.3 (DEV, DEL, ADD) EPG GuldelinelContIngency: PRIMARY CONTAINMENT CONTROL EPG Section: DW/T EPG Step: DW/T-3 EPG Statement: n/a l EP_G Basis: n/a PSTG Guideline / Contingency: DRiWELLCONTROL PSTG Section: DW/T PSTG Step: DW/T-4 PSTG Statement: When drywell sprays are no longer required to maintain drywell temperature below 280 'F, terminate spraying and restore the RRUs. PSTG Justifiestion: Once drywell temperature conditions are stabilized within acceptable ranges, and can be maintained without the assistance of the drywell spray system, the operator is directed to secure from its use and return the system to standby. I l l i JDDA - 49 l u____ _ _ _ _ _ .-.______ .
msme Justification for Deletion, Deviation, or Addition o" DEV pE: to the BWROG Emergency Procedure Guideline, Rev.3 (DEV, del ADD) EPG Guideline / Contingency: FRIMARY CONTAINMENT CONTROL EPG Section: DW/T EPG Step: DW/T-3 EPG Statement: If drywell temperature cannot be maintained below [340 'F (maximum temperature at which ADS qualified or drywell design temperature, whichever is lower)], EMERGENCY RPV DEPRESSURIZATION IS REQUIRED; enter (procedure developed from the RPV Control Guideline] at [ Step RC-1] and execute it concurrently with this procedure. EPG Basis: If drywell temperature cannot otherwise be maintained below equipment qualification and structural design temperature limits, continued drywell heatup is reduced or terminated by rapidly depressurizing the RPV. The instruction to enter the RPV Control Guideline provides the mechanism by which Contingency #2 (Emergency RPV Depressurization) is reached. PSTG Guidellne/ Contingency: DRYWELLCONTFIOL PSTG Sect i on: DW/T PSTG Step: DW/T-4 PSTG Statement: If drywell temperature cannot be maintained below 280 'F (drywell design temperature), EMERGENCY RPV DEPRESSURIZATION IS REQUIRED; enter (procedure developed from the Contingency #2] and execute it concurrently with this procedure. PSTG Justifleation: Rather than enter Contingency #2 by way of the RPV Control Guideline, the operator is required to proceed to Contingency #2 directly. Concurrent control of the three interrelated RPV parameters (RPV water level, RPV pressure, and RPV reactor power) are the normal functions of the operating crew, and are defined in both normal as well as emergency operating procedures. JDDA - 50 s rz
Justification for Deletion, Deviation, or Addition ms m " E: DEV to the BWROG Emergency Procedure Guideline, Rev.3 (DEV. DEL. ADD) EPG Guldeline/ Contingency: PRIMARY CONTAINMENT CONTROL EPG Section: PC/P EPG Step: PC/P-1 l EPG Statement: Operate [the following systems as required:
. Containment pressure control systems. Use containment pressure control system operating procedure.]
. SBGT [and drywel purge), only when the temperature in the space being evacuated is below
[212 'F (Maximum No.r.ondensib!e Evacuation Temperature)). Use [SBGT and drywell purge operating procedures]. EPG Basis: System and general plant operating procedures typically provide instructions for controlling and maintaining primary containment pressure within Technical Specification limits during routine plant operations, both shutdown and at power. Step PC/P-1 provides a smooth transition from normal operating procedures to emergency operating procedures and assures that the normal methods of primary containment pressure control have been placed into operation in advance of employing more complex actions to terminate increasing primary containment pressure. PSTG Guidellne/ Contingency: DRYWE11 CONTROL PSTG Section: PC/P lPSTG Step: PC/P 1 PSTG Statement: If dryweil pressure is > 2.S psig, attempt to reduce drywell pressure with the following:
- Drywell RRUs
. SBGT, only when the temperature in the space to be evacuated is below 212 'F (Maximum Noncondensible Evacuation Temperature).
PSTG Justification: Vermont Yankee operational transient procedure OT 3111 *High Drywell Pressure" provides the operator with direction up to 2.2 psig. The PSTG provides guideance should the drywell pressure exceed the entry condition of 2.5 psig. A specific value was utilized to provide the operators with unambiguous direction. The specific pressure control systems are identified without reference to specific procedures since this knowledge is part of basic, continuing operator training. t l l JDDA - 51
msmCA Justification for Deletion, Deviation, or Addition E DEL i to the BWROG Emergency Procedure Guideline, Rev.3 i (oev.on. Aco) ! EPG Guideline / Contingency: PRIMARY CONTAINMENT CONTROL EPG Section: PC/P EPG Step: PC/P-1 EPG Statement q Reference to Caution #21 " Elevated suppression chamber pressure may trip the RCIC turbine on high exhaust pressure." j I EPG Basis: The applicability of Caution #21 is identified at this step because of the direct effect elevated primary containment pressure has on RCIC turbine exhaust backpressure. PSTG Guidellno/ Contingency: DRYWELLCONTROL PSTG Section: PC/P PSTG Step: PC/P-1 PSTG Statement: n/a PSTG Justifleation: Since elevated primary containment pressure has an effect on many other systems besides RCIC (i.e.: HPCI. SRVs, PCIS), and since these are all well known to the operators via training, it was decided that this caution was both inadequate and potentially misleading. It was not included for these reasons. JDDA - 52 _ _ _ _ _ _ . _ _ _ _ _ _ _ _ _ _ _ _ _ _ . e o
JUSTIFICA N Justification for Deletion,- Deviation, or Addition to the BWROG Emergency Procedure Guideline, Rev.3 (DEV. DEL, ADD) EPG Guldeline/ Contingency: PRIMARY CONTAINMENT CONTROL EPG Section: PC/P EPG Step: PC/P 1 l EPG Statement: n/a EPG Basis: n/a PSTG Guideline / Contingency: DRYWELLCONTROL PSTG Section: PC/F PSTG Step: PC/P-1 PSTG Statement: Reference to Caution #28 "Do not vent via SGTS if drywell pressure is greater than 7 psig." PSTG Justification: The applicability of Caution #28 is identified at this step because analysis has shown that at this drywell pressure, the downsteam pressure in the SGTS trains (assuming steam flow through the system) could exceed the SGTS pressure rating. (reference: " Analysis of Primary Containment Venting Through Atmospheric Control and Standby Gas Treatment Systems for VYNPC", GP-R-213031, General Physics Corp., July 1984) JDDA - 53 _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ c. e
Justification for Deletion, Deviation, or Addition ESEA E1 ADD to the BWROG Emergency Procedure Guideline, Rev.3 (DEV. DF', i.JO) 4 EPG Guideline / Contingency: PRIMARY CONTAINMENT CONTROL EPG Section: PC/P EPG Step: PC/P 1 l EPG Statement: n/a EPG Basis: li/a PSTG Guldeline/ Contingency: DRYWELLCONTROL PSTG Section: PC/P lPSTG Step: PC/P-1 PSTG Statement: Reference to Caution #31
- Control Room indication of the following parameters are subject to instrument error:
. Drywell tempererature +/- 10 'F
- Reactor pressure +/- 40 psl*
PSTG Justification: This caution was added since drywell temperature is the temperature of the space being evacuated. Since the operator is required to stay below the Maximum Noncondensible Evacuation Temperature, it was deemed necessary that the magnitude of instrument inaccuracy for post accident conditions be included within the procedure. (reference: Memo, M.E. Palionis to D.E. LaBarge, " Addition of Caution to Emergency Operating Procedures, dated 6/20/86) i JDDA - 54 _ _ _ _ - _ _ _ _ - _ _ _ _ _ - _ _ _ _ _ _ _ - - _- -_ m_ o
Justification for Deletion, Deviation, or Addition msmc " E: DEV to the BWROG Emergency Procedure Guideline, Rev.3 (DEV, DEL. A00) l EPG Guldeline/ Contingency: PRIMARY CONTAINMENT CONTROL EPG Section: PC/P EPG Step: PC/P-2 EPG Statement: Before suppression chamber pressure reaches [the Pressure Suppression Pressure] [17.4 psig (Suppression Chamber Spray initiation Pressure)), but only if [ suppression chamber pressure is above 1.7 psig (Mark lil Containment Spray initation Pressure Limit)) (suppression pool water level is below 24 ft. 6 in. (elevation of suppression pool spray nozzles)], initiate suppression pool sprays. I EPG Basis: Operation of suppression pool sprays reduces primary containment pressure by condensing steam that may be oresent in the suppression chamber and by absorbing energy from noncondensibles through the processes of evaporative cooling and convective cooling. Maintaining the pressure below the Pressure Suppression Pressure curve accomplishes the dual objectives of assuring the continued function of the pressure suppression system and limiting primary containment pressure below design. PSTG Guldeline/ Contingency: DRWELLCONTROL PSTG Section: PC/P PSTG Step: PC/P-2 PSTG Statement: If drywell pressure is > 2.5 psig, but only if suppression pool water level is below 25 ft. (elevation of suppression pool spray nozzles), initiate suppression pool sprays and maintain suppression chamber airspace pressure below 19 psig (Suppression Chamber Spray initiation Pressure) using the following systems:
*RHR Fire System PSTG Justifleation:
If the action taken in PSTG step PC/P-1 was unsuccessful, the conservative approach was to initiate suppression pool sprays as there would be no adverse consequences. The choice for the upper control limit equal to the Suppression Chamber Spray Initiation Pressure was based on its conservatism. This is due to the fact that the value of the Suppression Chamber Spray Initiation Pressure is bounded by the Pressure Suppression Pressure curve. in addition, an alternate supply of water for suppression chamber sprays is provided. This was added as a result of the Vermont Yankee Containment Safety Study, and provides a means of cooling the drywell for events such as Station BWout. JDDA - 55 m ,
JUSilFICA N Justification for Deletion, Deviation, or Addition to the BWROG Emergency Procedure Guideline, Rev.3 (OEV. DEL A00) EPG Guldeline/ Contingency: PRIMARY CONTAINMENT CONTROL EPG Section: PC/P EPG Step: PC/P-3 EPG Statement: If suppression chamber pressure exceeds [17.4 psig (Suppression Chamber Spray initiation Pressure)) but only if [ suppression chamber temperature and drywell pressure are below the Drywell Spray Initiation Pressure Limit], [ shut down recirculation pumps and drywell cooling fans andl initiate drywell sprays (restricting flow rate to less than 720 gpm (Maximum Drywell Spray Flow Ra9 Limit)). EPG Basis: Initiating drywell sprays when the suppression chamber pressure exceeds the Suppression Chamber Spray initiation Pressure mitigates conditions which might otherwise lead to chugging. Spray initiation above the DWSIPL may, through the combined effects of evaporative cooling and convective cooling, result in a containment (drywell and suppression chamber) depressurization rate which exceeds the relief capacity of the drywell and reactor building vacuum breakers. As a result, the negative design pressure of the primary containment may be exceeded, leading to failure of the primary containment. PSTG Guldeline/ Contingency: DRYWELLCONTROL PSTG Section: PC/P 'STG Step: PC/P-3 PSTG Statement: If suppression chamber pressure exceeds 1g psig (Suppression Chamber Spray initiation Pressure) but only if suppression chamber airspace temperature and pressure are below the Drywell Spray initiation Pressure Limit:
- 1. Shutdown recirculation pumps and drywell RRUs.
- 2. Isolate SGTS before spraying.
- 3. Spray the drywell using the following systems:
RHR + Fire System PSTG Justifleation: The addition of th6 step directing the operator to isolate SGTS before spraying was made due to concern for the charcoal beds. Since the operator was previously directed to utilize this system as a vent path, and assuming it was still operational, continued use while spraying the drywell could result in excessive op across the beds, and failure of the SGTS train housing. In addition, an alternate supply of water for drywell spray is provided. This was added as a result of the Vermont Yankee Containment Safety Study, and provides a means of cooling the drywell for events such as Station Blackout. JDDA - 56 s r
l l l JUSTIFICA N Justification for Deletion, Deviation, or Addition to the BWROG Emergency Procedure Guideline, Rev.3 (DEV. DEL. ADD) EPG GuldslinelContIngency: PRIMARY CONTAINMENT CONTROL EPG Section: PC/P EPG Step: PC/P-4 EPG Statement: If suppression chamber pressure cannot be maintained below [the Pressure Suppression Pressure), ENERGENCY RPV DEPRESSURIZATION IS REQUIRED. EPG Basis: If pressure ecntinues to increase despite the actions in previous steps, the primary containment may reach or exceed its design pressure. Emergency RPV Depressurization is therefore required to terminate or minimize continued pressurization of the primary containment air space. If primary containment pressure has reached the Pressure Suppression Pressure, the high drywell pressure condition has already required entry to the RPV Control Guideline so that no explicit statement to enter the RPV Control Guideline need be included. PSTG Guideline / Contingency: DRYWELLCONTROL PSTG Section: PC/P PSTG Step: PC/P-4 PSTG Statement: If suppression chamber pressure cannot be maintained below the Pressure Suppression Pressure, EMERGENCY RPV DEPRESSURIZATION IS REQUIRED; enter [ procedure developed from Contingency #2] and execute it concurrently with this procedure. PSTG Justification: Since high drywell pressure is not an entry condition into VY PSTG's RPV Control Guideline, specific direction is provided to enter the contingency dealing with RPV depressurization. Further, the operator is directed to continue in this procedure concurrent with RPV depressurization. JDDA - 57 _ _ _ _ _ _ _ _ _ e o
Justification for Deletion, Deviation, or Addition msmc " E. DEV to the BWROG Emergency Procedure Guideline, Rev.3 (DEV.0EL A00) EPG GuldelinelContingency: PRIMARY CONTAINMENT CONTROL EPG Section: PC/P l EPG Step: PC/P-5 EPG Statement: i If suppression chamber pressure cannot be maintained below [the Primary Containment Design Pressure), RPV FLOODING IS REQUIRED. EPG Basis: Suppression chamber pressure in excess of the Primary Containment Design Pressure indicates that SBGT, suppression pool sprays, drywell sprays, and RPV blowdown have been insufficient to effectively control suppression chamber pressure. Flooding the RPV will also reduce suppression chamber pressure by forcing subcooled liquid out the break to terminate steam discharge to the containment and to condense steam in the drywell. PSTG Guldeline/ Contingency: DRYWELLCONTROL PSTG Section: PC/P PSTG Step: PC/P-5 PSTG Statement: If suppression chamber pressure cannot be maintained below the Primary Containment Pressure Limit, RPV FLOODING IS REQUIRED; enter (procedure developed from Contingency #6] and execute it concurrently with this procedure. PSTG Justification: Vermont Yankee's Primary Containment Pressure Limit (PCPL) was taken to be equal to it's Primary Containment Design Limit (PCDL), since it was assumed that primary containment integrity cannot be assured beyond this pressure. In addition, the operator is directed to continue in this procedure concurrent with RPV flooding. JDDA - 58 _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ ts e ;
Justification for Deletion, Deviation, or Addition msmc " E. DEV to the BWROG Emergency Procedure Guideline, Rev.3 l (DEv. DEL. ADD) EPG GuldelinelContIngency: PRIMARY CONTAINMENT CONTROL EPG Section: PC/P EPG Step: PC/P-6 EPG Statement: If suppression chamber pressure cannot be maintained below the Primary Containment Pressure Limit, then irrespective of whether adequate core cooling is assured: (
+ [lf suppression pool water level is below 24 ft. 6 in. (elevation of suppression pool spray nozzles),]
initiate suppression pool sprays.
. If [suppresson chamber temperature and drywell pressure are below the DWSIPL], [ shut down recirculation pumps and drywell fans and] initiate drywell sprays [ restricting flow rate to less than 720 gpm (Maximum Drywell Spray Flow Rate Limit)].
EPG Basis: If suppression chamber pressure cannot otherwise be maintained below the PCPL, diversion of RPV injection flow to the suppression pool and drywell spray systems is appropriate even if this will jeopardize adequate core cooling. Primary containment integrity must be maintained, even at the expense of adequate core cooling, to provide protection against the potential uncontrolled release of radioactivity to the environment. PSTG Guldellne/ Contingency: DRYWEU.CONEOL PSTG Section: PC/P PSTG Step: PC/P 6 PSTG Statement: If suppression chamber pressure cannot be maintained below the PCPL after the RPV has been flooded, but only if suppression chamber airspace temperature and pressure are below the DWSIPL, then irrespective of whether adequate core cooling is assured:
- 1. Shutdown recirculation pumps and drywell RRUs.
- 2. Isolate SGTS before spraying
- 3. Spray the drywell with the following:
- RHR Fire System
- 4. If suppression pool water level below 25 ft. (elev of spray nozzles), initiate suppression pool sprays.
PSTG Justification: Since this decision can have a significant affect on the course of the accident, before diversion of flow to the primary containment sprays it is first ascertained whether RPV Flooding has been successful. The addition of the step directing the operator to isolate SGTS before spraying was made due to concern for the charcoal beds. Since the operator was previously directed to utilize this system as a vent path, and assuming it was still operational, continued use while spraying the drywell could result in excessive op across the beds, and failure of the SGTS train housing. In addition, an alternate supply of water for drywell spray is provided. This was added as a result of the Vermont Yankee Containment Safety Study, and provides a means of cooling the drywell for events such as Station Blackout. l JDDA 59 _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ . _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ . _ .s e
L JUSTIFICA N Justification for Deletion, Deviation, or Addition to the BWROG Emergency Procedure Guideline, Rev.3 (DEV. DEL. ADD) d EPG GuldelinelContIngency: PRIMARY CONTAINMENT CONTROL EPG Section: PC/P EPG Step: PC/P-6 l EPG Statement: n/a i EPG Basis: n/a PSTG Guideline / Contingency: DRYWELLCONTROL PSTG Section: PC/P lPSTG Step: PC/P 6 PSTG Statement: Reference to Caution #22 " Defeating isolation interlocks may be required to accomplish this step." PSTG Justification: It is appropriate to apply this caution to step PC/P-6 since, if adequate coro cooling was not assured and RPV level was less than 2/3 core height, the drywell and suppression chamber spray valves could not be opened without first bypassing the LPCI logic 2/3 Core Height isolation interlock. JDDA - 60 n ,
i a JUSTIFICA N Justification for Deletion, Deviation, or Addition to the BWROG Emergency Procedure Guideline, Rev.3 (DEV. DEL ADD) EPG Guldeline/ Contingency: SECONDARYCOMAINlENT COMROL EPG Section: Entry Condition EPG Step: n/a l EPG Statement:
. Differential pressure at or above 0 in, of water EPG Basis:
A high secondary containment differential pressure presents a direct challange to the structural integrity of the secondary containment. PSTG Guideline / Contingency: SECONDARY CONTAINMENTCONTROL PSTG Section: Entry Condition lPSTG Step: n/a PSTG Statement: n/a PSTG Justiffeation: The secondary containment is designed to withstand,without structural failure or pressure relief, an internal overpressure corresponding to 7 inches of water. Panels, designed to fail at the limiting pressure, are provided for relief of pressures in excess of 7 inches of water. In addition, although a differential pressure above 0 in, of water represents a challenge to the SC boundary, there are no operator actions which cope with or prevent loss of structural integrity other than isolation of systems discharging into the secondary containment. The concurrent condition (s) of high area temperature and/or high area radiation level would prompt this operator action. Moreover, the loss of secondary containment in and of itself does not constitute an unsafe or emergency condition. The presence of high radiation levels within the secondary containment would also need to exist to constitute an emergency condition, and is addressed by the EPGs as described above. JDDA - 61 l
- _ _ _ _ _ _ _ _ _ _ . _ _ _ _ _ - x .- a
JUSTIFICA N Justification for Deletion, Deviatlen, or Addition to the BWROG Emergency Procedure Guideline, Rev.3 (DEV, DEL. A00) EPG Guldeline/ Contingency: SECONDARY CONTAINMENT CONTROL EPG Section: Entry Condition EPG Step: n/a l EPG Statement:
. A HVAC cooler differential temperature above the maximum normal operating differential temperature EPG Basis:
A high HVAC cooler differential temperature provides direct Indication that steam may be discharging into the secondary containment. PSTG Guldeline/ Contingency: SECONDARYCCNTAINMENT CONTROL PSTG Section: Entry Condition PSTG Step: n/a PSTG Statement: n/a PSTG Justification: The inlet and exit air temperatures for the coolers located in secondary containment are not instrumented, it is therefore not possible to establish a max normal operating differential temperature. Nor is it an accurate indication of degraded conditions within the secondary containment since the high AT may be the result of altered operating state of the HVAC cooler (i.e., increased cooling water flow, decreased air flow, decreased temperature of cooling water). JDDA - 62 _ _ _ _ _ _ _ _ _ _ _ _ _ __ _ _% 0
JUSTIFICA N Justification for Deletion, Deviation, or Addition to the BWROG Emergency Procedure Guideline, Rev.3 (DEV. DEL. A00) EPG Guideline / Contingency: SECONDARY CONTAINMENT CONTROL EPG Section: Entry Condition EPG Step: n/a EPG Statement:
. A HVAC exhaust radiation level above the maximum normal operating radiation level.
EPG Basis: n/a PSTG Guideline / Contingency: SECONDARY CONTAINMENTCONTROL PSTG Section: Entry Condition PSTG Step: n/a PSTG Statement:
. A Rx Bldg. HVAC exhaust radiation level above 14 mR/hr (secondary containment HVAC isolation setpoint)
PSTG Justification: As stated in the EPG basis, the "... conditions which require entry to the Secondary Containment Control Guideline are symptomatic of an emergency condition...". As stated in VY FSAR, Section 7.3, the high radiation trip setting selected is far enough above background radiation levels to avoid spurious isolation, yet low enough to provide timely detection of nuclear system process barrier leaks. Therefore, selection of the secondary containment HVAC isolation setpoint is an appropriate and conservative entry condition. JDDA 63 w a
Justification for Deletion, Deviation, or Addition mmc DEV to the BWROG Ernergency Procedure Guideline, Rev.3 (DEV. DEL, ADO) EPG Guldeline/ Contingency: SECONDARY CONTAINMENTCONTROL EPG Section: Entry Conditions EPG Step: n/a EECs Statement:
+ A floor drain sump water level above the maximum normal operating water level.
EPG Basis: A high floor drain sump level provides direct indication that steam or water may be discharging into the secondary containment, threatening safety related equipment and adding to the static load on secondary containment structures. PSTG Guideline / Contingency: SECONDARY CONTAINMENT CONTROL PSTG Section: Entry Conditions PSTG Step: n/a PSTG Statement:
. Continuous floor drain sump pump operation.
PSTG Justification: Floor drain sump level is controlled by sump pump actuation in response to a signal from a level switch. l Energization of the pump's start circuit is alarmed in the control room and is an indication of higher than normal sump water level. The entry condition also requires that the pump be operating continuously since, if it was cycling on and off intermittently, it would be fulfilling its design function and would not constitute an emergency condition, but rather an off-normal condition. This is addressed in OP3140, the Alarm Response Procedure. l JDDA - 64 s e
JUSTIFICA N Justification for Deletion, Deviation, or Addition to the BWROG Emergency Procedure Guideline, Rev.3 (DEv. DEL. ADD) EPG Guideline / Contingency: SECONDARY CONTAINfENTCONTROL EPG Section: Entry Conditions EPG Step: n/a l EPG Statement:
. An area water level above the maximum normal operating water level.
EPG Basis: A high area water level provides direct indication that steam or water may be discharging into the secondary containment, threatening safety related equipment and adding to the static load on secondary containment structures. PSTG Guldeline/ Contingency: SECONDARYCONTAINfENT CONTROL PSTG Section: Entry Conditions lPSTG Step: n/a PSTG Statement:
. An unexpected area water level above the maximum normal operating water level.
PSTG Justification: Given the fact that maximum normal operating water levels are so low (nominally chosen equal to t inch), and since there are times when area water level may exceed this which do not constitute an emergency condition (i.e., floor drain overflows during system drain down during refuel outago), the entry condition was modified to exclude those cases when it can be reasonably expected that an area water level exceeded its max normal operating level. JDDA - 65 1 i
. . - - - . _ . _ _ _ _ _ _ -__,_.___..______m___ _ _ _ _ _ _ , , , , , _ _ _ __ _ __ _ _,
JUSTIFICA N Justification for Deletion, Deviation, or Addition to the BWROG Emergency Procedure Guideline, Rev.3 (DEV. DEL. ADO) EPG Guideline / Contingency: SECONDARY CONTAINMENT CONTROL EPG Section: SC/T EPG Step: n/a EPG Statement: If while executing the following steps secondary containment HVAC exhaust radiation level exceeds (20 mR/hr (secondary containment HVAC isolation setpoint)]:
. Confirm or manually initiate isolation of secondary containment HVAC, and
. Confirm initiation of or manually initiate SBGT [only when the space being evacuated is below 212 'F].
EPG Basis: Confirming isolation of SC HVAC subsequent to receipt of a high radiation signal terminates any further release of radioactivity to the environment from this system. SBGT is the normal means employed under post-transient conditions for maintaining a negative SC pressure with respect to the atmosphere. The 212 *F restriction for use of SBGT is only applicable to those plants where initiation of a deluge sprinkler system would spray a major portion of the space being evacuated since the immediate pressure drop upon sprinkler system initiation in a saturated steam environment which is evacuated of non-condensibles may exceed the negative design pressure of SC. PST'G Guldellne/ Contingency: SECONDARY CONTAINMENT CONTROL PSTG Section: SC/T PSTG Step: n/a PSTG Statement: If while executing the following steps secondary containment HVAC exhaust radiation level exceeds 14 mR/hr (secondary containment isolation setpoint):
. Confirm or manually initiate isolation of secondary containment, and
. Confirm initiation of or manually initiate SBGT PSTG Justifleation:
The isolation of secondary containment HVAC occurs with a PCIS Group 3 initiation. Therefore, the operator will terminate further release of radioactivity to the environment from the SC HVAC system upon isolation of the secondary containment. In addition, Vermont Yankee does not have an extensive deluge sprinkler system in secondary containment which could result in a condition that would lead to exceeding the negative design pressure of secondary containment. JDDA - 66
l 1 JUSTIFICA N Justification for Deletion, Deviation, or Addition to the BWROG Emergency Procedure Guideline, Rev.3 (DEV. DEL. ADD) EPG Guideline / Contingency: SECONDARY CONTAINMENT CONTROL EPG Section: SC/T EPG Step: S C/T-3 EPG Statement: If any area temperature exceeds its maximum normal operating temperature, isolate all systems that are discharging into the area except systems required to shut down the reactor, assure adequate core cooling, or suppress a working fire. EPG Basis: Two possible sources exist in which heat may be added to the secondary containment in a quantity sufficient to increase area temperatures to above the maximum normal operating temperature: a fire, or a steam or liquid discharge from high-energy systems. Step SC/T-3 terminates the possible heat addition from one source, high energy systems. Not requiring isolation of systems used to suppress a working fire adequately addresses the other possible source of heat addition. PSTG Guideline / Contingency: SECONDARY CONTAINMENT CONTROL PSTG Section: SC/T PSTG Step: SC/I , PSTG Statement: If any &rea temperature exceeds its maximum normal operating temperature, isolate all systems that are discharging into the area except systems required to shut down the reactor, assure adequate core cooling, or suppress a fire. PSTG Justifleation: There is no definition of what is meant by a " working" fire, therefore this has been deleted. l l JDDA - 67
JUSTIFICA N Justification for Deletion, Deviation, or Addition to the BWROG Emergency Procedure Guideline, Rev.3 ) (CEV,0EL. ADD) i EPG Guideline / Contingency: SECONDARY CONTAINMENT CONTROL EPG Section: SC/T EPG Step: SC/T 4 i EPG Statement: If a primary system is discharging inio an area, then before any area temperature reaches its maximum safe operating temperature, enter (procedure developed from the RPV Control Guideline) at [ Step RC-1] and execute it concurrently with this procedure. EPG Basis: Entry to the RPV Control Guideline at Step RC-1 initiates a reactor scram to shut down the reactor and reduce to decay heat levels the energy that the RPV may be discharging to the secondary containment. PST'G Guideline / Contingency: SECONDARY CONTAINMENT CONTROL PSTG Section: SC/T PSTG Step: SC/T 4 PSTG Statement: If a primary system is discharging into an area, then before any area temperature reaches its maximum safe operating temperature:
- 1. Runback Recirc flow to minimum
- 2. Transfer electrical loads to the Startup Transformers
- 3. Manually Scram the reactor; enter OE 3t00 [ scram procedure) and execute it concurrently with this procedure.
PSTG Justifleation: Rather than initiate a reactor scram via entry of the RPV control guideline, the operator is specifically directed to manually scram the reactor after first establishing plant conditions that will minimize this transient's effect on plant operation. Additionally, he is directed to execute the scram procedure concurrently to ensure tnat plant systems are aligned appropriately for the changed plant operating condition (i.e.: all rods inserted, IRMs and SRMs driven into the core, etc.). JDDA - 68
., a
JUSTIFICA N Justification for Deletion, Deviation, or Addition to the BWROG Ernergency Procedure Guideline, Rev.3 (DEV. DEL ADD) EPG Guldeline/ Contingency: SECONDARY CONTAINMENT CONTROL EPG Section: SC/T EPG Step: SC/T-5 l EPG Statement: If a primary system is discharging into an area and an area temperature exceeds its maximum safe operating temperature in more than one area, EMERGENCY RPV DEPRESSURIZATION IS REQUIRED. EPG Basis: Beyond the maximum safe operating temperature, continued operation of safety related systems and continued integrity of the secondary containment is no longer assured. The criteria of "more than one area
- specified in this step insures that the secondary containment temperature rise is not an isolated occurance, but does in fact represent a wide-spread and direct threat to secondary containment.
PSTG Guideline / Contingency: SECONDARY CONTAINMENT CONTROL PSTG Section: SC/T PSTG Step: SC/T 5 PSTG Statement: If a primary system is discharging into secondary containment, then when the maximum safe operating temperature for a limiting combination is exceeded, EMERGENCY RPV DEPRESSURIZATION IS REQUIRED. 1 PSTG Justification: In establishing the maximum safe operating temperature for the various areas in secondary containment, the critical plant areas and equipment were first determined, then the environmental tolerence levels for the critical equipment was obtained. Critical equipment was defined as that equipment needed for shutdown and decay heat removal. All combinations of two areas are not applicable. Only those combinations of affected areas which could result in potential loss of both redundant trains of a required safety, or critical, function need be considered. This addresses preservation of reactivity control, ECCS initiation, RPV level and pressure control, decay heat removal. ECCS cooling, and post-accident monitoring functions. (reference: Memo, R.E. Swenson to S.R. Miller, *BWROG EPG Review - Revision 1*, dated 6/9/86) JDDA - 69 - _ _ _ _ _ _ - _ _ _ _ _ _ _ - _ _ _ _ _ _ _ _ _ - . _ _ _ _ _ . n
JUSTIFICA N Justification for Deletion, Deviation, or Addition to the BWROC Emergency Procedure Guideline, Rev.3 (DEV, DEL A00) EPG Guideline / Contingency: SECONDARY COMAINMENT COMROL EPG Section: SC/T l EPG Step: n/a EPG Statement: n/a l 1 EPG Basis: i n/a PSTG Guldeline/ Contingency: SECONDARY CONTAINMENT CONTROL PSTG Section: SC/T PSTG Step: SC/T-6 PSTG Statement: Establish RPV shutdown cooling once conditions permit. PSTG Justification: This action is consistant with the direction provided by the EPG Contingency #2, " Emergency RPV Depressurization", which the operator was required to initiate in the previous step. It is added here to emphasis the importance of establishing cold shutdown conditions as soon as possible to mitigate the conditions in the secondary containment. JDDA - 70 _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ - _ _ _ _ _ _ . n
JUSTIFICATION Justification for Deletion, Deviation, or Addition to the BWROG Emergency Procedure Guideline, Rev.3 (oEV. DEL ADO) EPG Guldeline/ Contingency: SECONDARY CONTAINMENTCOfRROL EPG Section: SC/R EPG Step: SC/R-1 EPG Statement: If any area radiation level exceeds its maximum t'armal operating radiation level, isolate all systems that are discharging into the area except systems required to shut down the reactor, assure adequate core cooling, or suppress a working fire. EPG Basis: 4 Action is taken to isolate systems that are discharging into the secondary cor.tainment to terminate possible sources of radioactivity release to the secondary containment. Fire fighting systems are not sources of radioactivity, thus there is no requirement to isolate them. PSTG Guldeline/ Contingency: SECONDARY CONTAINMENT CONTROL PSTG Section: SC/R PSTG Step: SC/R-1 PSTG Statement: If an area radiation level exceeds its maximum normal operating radiation level, isolate all systems that are discharging into the area except systems required to shut down the reactor, assure adequate core cooling, or suppress a fire. PSTG Justification: There is no definition of what is meant by a " working" fire, therefore this has been deleted. 4 JDDA - 71 l -- _ _ . _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _
1 JUSTIFICA N Jus *ification for Deletton, Deviation, or Addition to tL, BWROG Emergency Procedure Guideline, Rev.3 ' (DEV. DEL ADD) EPG Guideline / Contingency: SECONDARY CONTAINMENT CONTROL EPG Section: SC/R EPG Step: SC/R-2 i l EPG Statement: If a primary system is discharging into an area then before any area radiation level reaches its maximum safe operating radiation IcVel, enter (procedure developed from the RPV Control Guideline] at [ Step RC-1] and execute it concurrently with this procedure. EPG Basis: Entry to the RPV Control Guideline at Step RC-1 initiates a reactor scram to shut down the reactor and reduce to decay heat levels the energy that the RPV may be discharging to the secondary containment. Since primary systems are the sources of radioactivity release, the action of Step SC/R 2 should be i adequate to reverse the increasing containment radiation level trend.
=.
PSTG Guidellne/ Contingency: SECONDARY CONTAINMENT COtRROL PSTG Section: SC/R PSTG Step: SC/R 2 PSTG Statement: If a primary system is discharging into an area tbi, before any area radiation level reaches its maximum safe operating radiation level:
- 1. Runback Recire flow to minimum
- 2. Transfer electrical loads to the Startup Transformers
- 3. Manually Scram the reactor; enter OE 3100 [ scram procedure] and execute it concurrently with this procedure.
PSTG Justifiestion: Rather than initiate a reactor scram via entry of the RPV control guideline, the operator is specifically i directed to manually scram the reactor after first establishing plant conditions that will minimize this j transient's effect on plant operation. Additionally, he is directed M exute the scram procedure concurrently to ensure that plant systems are aligned approprit my te the changed plant operating condition (i.e.: all rods inserted, IRMs and SRMs driven into the , w, etc.). I JDDA - 72
JUSTIFICATION Justification for Deletion, Deviation, or Addition to the BWROG Emergency Procedure Guideline, Rev.3 (DEV. DEL, ADD) EPG Guideline / Contingency: SECONDARY CONTAINMENTCONTROL EPG Section: SC/R EPG Step: SC/R 3 EPG Statement: If a primary system is discharging into an area and an area radiation level exceeds its maximum safe operating radiation levelin more than one area. EMERGENCY RPV DEPRESSURIZATION IS REQUIRED. EPG Basis: The criteria of 'more than one* specified in this step indicates that the secondary containment radiation level increase to above the maximum safe operating radiation level is not just an isolated occurrence, but does in fact represent a widespread and direct threat of significant radioactivity release. Depressurizing the RPV immediately places the primary system in the lowest possible energy state, minimiting the driving head and flow of primary systems that are unisolated and are discharging into areas of the secondary containment. P ST'G Guideline / Contingency: SECONDARY CONTAINMENT CONTROL PSTG Section: SC/R PSTG Step: n/a PSTG Statement: n/a PSTG Justifleation: Required safety, or critical, functions such as reactivity control, ECCS initiation, RPV level and pressure control, decay heat removal, ECCS cooling, and post accident monitoring functions are environmentally qualified to withstand the radiation levels resulting from a severely damaged core. The present criteria for choosing secondary containment maximum safe operating radiation levels is based on operator stay time, and is a conservative value equal to 100x the normal operating radiation levels. Minimization of significant radioactivity release is accomplished via secondary containment isolation. It should also be noted that primary system discharge will also resu!! in high SC temperatures much sooner than high radiation levels, and would result in the operator performing RPV dapressurization. (reference: Memo, R.E. Swenson to S.R. Miller, 'BWROG EPG Review - Revision 1*, dated 6/9/86) JDDA - 73
JUSTIFICA N Justification for Deletion, Deviation, or Addition to the BWROG Emergency Procedure Guideline, Rev.3 (DEV. DEL. ADD) l l EPG Guideline / Contingency: SECONDARY CONTAINMENT CONTROL EPG Section: SC/L EPG Step: SC/L 1 l EPG Statement: If any floor drain sump or area water level is above its maximum normal operating water level, operate l available sump pumps to restore and maintain it below 'ts maximum normal operating water level. EPG Basis: Sump pump operation is the normal method for controlling water inventory in secondary containment areas. Step SC/L 1 thus provides a smooth transition from normal operating procedures to emergency operating procedures, assuring that the normal methods of secondary containment water level control are employed in advance of requiring use of more severe actions to terminate progressively increasing secondary containment water levels. PSTG Guldeline/ Contingency: SECONDARY CONTAINMENT CONTROL PSTG Section: SC/L PSTG Step: SC/L 1 PSTG Statement: If an area water level is above its maximum normal operating water level, operate available sump pumps to restore and inaintain it below its maximum normal eperating water level. PSTG Ju stif f eatio n: Floor drain sump level is controlled by sump pump actuation in response to a signal from a level switch. Energization of the pump's start circuit is alarmed in the control room and is an indication of higher than normal sump water level. This indicates it is fulfilling its design function and would not constitute an emergency condition, but rather an off-normal condition. This is addressed in OP3140, the Alarm Response Procedure. If it failed to start, and resulted in accumulation of water in secondary containment areas, this could indicate an emergency condition and is properly addressed in the PSTG step above. JDDA - 74 _ _ _ _ _ _ _ . _ n
JUSTIFICA N Justification for Deletion, Deviation, or Addition to the BWROG Emergency Procedure Guideline, Rev.3 (DEV. DEL, W ; l I EPG Guideline / Contingency: SECONDARY COffTAINMENT COffTROL EPG Section: SC/L EPG Step: SC/L-1 I EPG Staterggatl , if any floor drain sump or area water level cannot be restored and maintained below its maximum normal operating water level, isolate all systems that are discharging water into the sump or area l I except systems required to shut down the reactor, assure adequate core cooling, or suppress a working fire. EPG Besls: Isolating discharges to the secondary containment is the direct and most appropriate action for terminating increasing area water levels if the normal methods of water level control are unavailable or ineffectual. PSTG Guldeline/ Contingency: SECONDARY CONTAINMEN'T CONEOL PSTG Section: SC/L PSTG Step: SC/L 1 PSTG Statement: If any area water level cannot be maintained below its maximum normal operating water level, isolate all systems discharging water into the sump or area except systems required to shut down the reactor, assure adequate core cooling, or suppress a fire. PSTG Justification: There is no definition of what is meant by a " working" fire, therefore this has been deleted. Floor drain sump level is controlled by sump pump actuation in response to a signal from a level switet Energization of the pump's start circuit is alarmed in the control room and is an indication of higher tha - normal sump water level. This indicates it is fulfilling its design function and would not constitute an emergency condition, but rather an off-normal condition. This is addressed in OP3140, the Alarm Response Procedure, if it failed to start or was ineffectual, and resulted in accumulation of water in secondary containment areas, this could indicate an emergency condition and is properly addressed in the PSTG step above. JDDA - 75 m
l l JUSTIFICA Justification for Deletion, Deviation, or Addition to the BWROG Emergency Procedure Guideline, Rev.3 (DEV. DEL ADO) l EPG Guldeline/ Contingency: SECONDARY CONTAINMENT CONTROL EPG Section: SC/L EPG Step: SC/L-2 EPG Statement: If a primary system is discharging into an area, then before any floor drain sump or area water level reaches its maximum safe operating water level, enter [ procedure developed from the RPV Control ! Guideline] at [ Step RC-1] and execWe it concurrently with this procedure. EPG Basis: Entry to the RPV Control Guideline at Step RC-1 initiates a reactor scram to shut down the reactor and reduce to decay heat levels the energy that the RPV may be discharging to the secondary containment. PSTG Guldellne/ Contingency: SECONDARY CONTAINMENTCONTROL PSTG Section: SC/L PSTG Step: SC/L-2 PSTG Statement: If a primary system is discharging into secondary containment, then before any area water level reaches its maximum safe operating water level:
- 1. Runback Recirc flow to minimum
- 2. Transfer electrical loads to the Startup Transformers
- 3. Manually Scram the reactor; enter OE 3100 [ scram procedure] and execute it concurrently with this procedure.
PSTG Justification: Rather than state " discharging into an area *, we choose to state " discharging into secondary containment" since a discharge anywhere in secondary containment would eventually lead to accumulation of water in one or more of the areas of interest. Rather than initiate a reactor scram via entry of the RPV control guideline, the operator is specifically directed to manually scram the reactor after first establishing plant conditions that will minimize this transient's effect on plant operation. Additionally, he is directed to execute the scram procedure concurrently to ensure that plant systems are aligned appropriately for the changed plant opterating condition (i.e.: all rods inserted, IRMs and SRMs driven into the core, etc.). l JDDA - 76 i E _ - - - -_ -- _ j
M CA N Justification for Deletion, Deviation, or Addition e: DEV to the BWROG Emergency Procedure Guideline, Rev.3 (DEV. DEt, ADD) EPG Guldeline/ Contingency: SECONDARY CONTAINMENTCONTROL EPG Section: SC/L EPG Step: SC/L 3 l EPG Statement: If a primary system is discharging into an area and a floor drain sump or area water level exceeds its maximum safe operating water levelin more than one area, EMERGENCY RPV DEPRESSURIZATION IS REQUFED. EPG Basis: Beyond the maximum safe operating level, flooding of safety related equipment may occur; continued safe operation of the plant and continued integrity of the secondary containment is no longer assured. Depressurizing the reactor under these conditions immediately places the primary system in the lowest possible energy state. PSTG Guldeline/ Contingency: SECONDARY CONTAINMENT CONTROL PSTG Section: SC/L PSTG Step: SC/L-3 l PSTG Statement: If the maximum saie operating water level is exceeded in more than one area, EMERGENCY RF V DEPRESSURIZATION IS REQUIRED. PSTG Justifleation: The reference in the EPG step to primary system discharge was deleted since flooding of secondary containment areas by other than primary systems (i.e., SW system) could also result in flooding of safety related equipment. Under these circumstances, it is still appropriate to depressurize the reactor, i thereby placing the primary system in a safer condition. i JDDA - 77 _ _ _ - _ _ _ _ _ _ _ - - _ _ _ _ _ _ . i
JUSTIFICA Justification for Deletion, Deviation, or Addition to the BWROG Emergency Procedure Guideline, Rev.3 (DEV, DEL ADD) I EPG Guldeline/ Contingency: SECONDARY CONTAINMENT CONTROL EPG Section: SC/L EPG Step: n/a l EPG Statemeq1; n/a EPG Basis: n/a PSTG Guidellne/ Contingency: SECONDARY CONTAINMENTCONTROL PSTG Section: SC/L PSTG Step: SC/L-4 PSTG Gistement: Establish RPV shutdown cooling once conditions permit. PSTG Justification: This action is consistant with the direction provided by the EPG Contingency #2, " Emergency RPV Depressurization", which the operator was required to initiate in the previous step. It is added here to emphasis the importance of establishing cold shutdown conditions as soon as possible to mit!pte the conditions in the secondary containment. JDDA - 78
Justification for Deletion, Deviation, or Addition msmCA " E: DEL to the BWROG Emergency Procedure Guideline, Rev.3 (DEV. DEL. ADD) EPG Guldeline/ Contingency: RADIOACTIVITY RELEASE CONTROL EPG Section: Entry Condition EPG Step: n/a l EPG Statement: Offsite radioactivity release rate above [3 Ci/sec (release rate which requires an Alert)). EPG Basis: l The entry condition for the Radioactivity Release Control Guideline directly relates to the purpose of the guideline and provides the vehicle for coordinated execution of emergency operating procedures and the l emergency plan. The specific value selected for this entry condition corresponds directly to an action i level in the emergency plan it is sufficiently high that it is not expected to occur during normal operation but sufficiently low that, of and by itself, it does not threaten the health and safety of the public. PSTG Guldellne/ Contingency: n/a 3 PSTG Section: n/a PSTG Step: n/a PSTG Statement: n/a l PSTG Justification: Since both action steps in the EPG Radioactivity Release Control Guideline have been deleted, there is no longer a need for an entry condition. Further, coordination between the emergency operating procedures and the emergency plan is accomplished via the Technical Support Center (TSC). This would be staffed per emergency plan implementing procedures, as referenced in AP 3125, which the operators would enter via the emergency operating procedures. (reference: Memo, R.E. Swenson to S.R. Miller, *BWROG EPG REVIEW - REVISION 1", dated 6/9/86) l JDDA - 79 i
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JUSTIFICA N Justification for Deletion, Deviation, or Additlo: to the BWROG Emergency Procedure Guideline, Rev.3 (DEV, DEL. A00) EPG Guideline / Contingency: RADIOACTIVITY RELEASE CONTROL EPG Section: R/R EPG Step: R/R 1 EPG Statement: Isolate all primary systems that are discharging into areas outside the primary and secondary containments except systems required to assure adequate core cooling or shut down the reac:or. EPG Basis: Isolating primary system discharges outside primary and secondary containments is the most direct and appropriate action for terminating radioac+ y release. Isolation of those systems required to assure adequate core cooling or shut down the reactor is not appropiate because inability to assure adequate core cooling or shut down the reactor may ultimately result in much larger releases. PSTG Guidellne/ Contingency: n/a PSTG Section: n/a PSTG Step: n/a PSTG Statement: n/a PSTG Justifleation: The isolation step is redundant to the EPG/SC isolation action and would be pre-empted. (reference: Memo, R.E. Swenson to S.R. Miller, *BWROG EPG REVIEW - REVISION 1", dated 6/9/86) l l l l JDDA - 80 \ . a
JUSTIFICA N Justification for Deletion, Deviation, or Addition to the BWROG Emergency Procedure Guideline, Rev.3 (DEV. DEL ADD) EPG Guldeline/ Contingency: RADIOACTIVITY RELEASE CONTROL EPG Section: R/R EPG Step: R/R-2 EPG Statement: If offsite radioactivity release rate approaches or exceeds [91 Ci/sec (release rate which requires a General Emergency)] and a primary system is discharging into an area outside the primary and secondary containments, EMERGENCY RPV DEPRESSURIZATION IS REQUIRED; enter [ procedure developed from the RPV Control Guideline] at (Step RC-1] and execute it cc 1 currently with this procedure. I EPG Basis: Depressurizing the RPV immediately reduces the driving head and flow from the primary systems that are discharging outside the primary and secondary containments. The instruction to enter the RPV Control Guideline provides the mechanism by which Contingency #2 (Emergency RPV Depressurization) is reached. PSTG Guidellne/ Contingency: n/a PSTG Section: n/a PSTG Step: n/a PSTG Statement: n/a PSTG Justification: This depressurization action step is superfluous. A large break by itself results in rapid depressurization whether or not this depressurization step is reached. A small break threatening core cooling due to inability to maintain level at high pressure would result in depressurization via the level control procedure. A small break for which cooling is maintained would not result in reaching the depressurization action level. (reference: Memo, R.E. Swenson to S.R. Miller, "BWROG EPG REVIEW - REVISION 1", dated 6/9/86) JDDA - 81 g
JUSTIFICA N Justification for Deletion, Deviation, or Addition to the BWROG Emergency Procedure Guideline, Rev.3 (DEV, DEL. ADD) EPG GuidellnelContInger ey: CONTINGENCY #1 LEVELRESTORATION EPG Section: C1 EPG Step: n/a EPG Statement: If while executing the following steps:
+ Boron injection is required, enter [ procedure developed from CONTINGENCY #7].
RPV water level cannot be determined, RPV FLOODING IS REQUIRED; enter (procedure developed from CONTINGENCY #6).
. RPV FLOODING is required, enter (procedure developed from CONTINGENCY #6).
EPG Basis: When Boron injection or when RPV Flooding is required, the actions required for control of RPV water level differ from those prescribed in Contingency #1; additional factors must be considered in determining which RPV water level band should be maintained, which injection systems and alternate I injection subsystems should be used, and what injection f aw rate should be established. PSTG Guideline / Contingency: CONTINGENCY #1 LEVELRESTORATION PSTG Section: C1 PSTG Step: n/a PSTG Statement: If while executing the following steps RPV water level cannot be determined, RPV FLOODING IS REQUIRED; enter (procedure developed from CONTINGENCY #6]. PSTG Justification: Vermont Yankee has not chosen to implement Contingency #7, therefore this over-ride step is not l required. Since the remaining over-ride steps are repetitive, they have been consolidated into one. Note that operator training and procedure setup precludes concurrent execution of both RPV level control procedures. JDDA - 82 _m_ m
msme Justification for Deletion, Deviation, or Addition . DEL to the BWROG Emergency Procedure Guideline, Rev.3 (DEV, DEL. ADD) EPG Guideline / Contingency: CONTINGENCY #1 LEVELRESTORATION EPG Section: C1 EPG Step: C1-1 l EPG Statement: Initiate IC. EEG Basis: Prior to initiatioin, a significant quantity of relatively cold water is contained in the tube bundles and condensate return piping of the isolation condenser (IC). Initiating the isolation condenser releases this water into the RPV. l PSTG Guldeline/ Contingency: CONTINGENCY #1 -LEVEL RESTORATION PSTG Section: C1 PSTG Step: n/a PSTG Statement: n/a PSTG Justification: Vermont Yankee does not have an isolation condenser. J LsD A - 8 3
Justification for Deletion, Deviation, or Addition WSMCA " E, DEV to the BWROG Emergency Procedure Guideline, Rev.3 (DEV, DEL ADD) l EPG Guideline / Contingency: CONTINGENCY #1 -LEVEL RESTORATION EPG Section: C1 EPG Step: C 1 -2 EPG Statement: Line up for injection and start pumps in 2 or more of the following injection subsystems: ,
. Condensate
.HPCS
.LPCIA LPCIB
. LPCS A
. LPCS-B EPG Basis:
The purpose of lining up and starting pumps in injection subsystems is to provide assurance that water , will be injected into the RPV during and following a blowdown from high pressure. At least two subsystem are required in this step to accomodate the possibility that one subsystem may not operate properly or that a break may exist in the injection flowpath of one subsys'am. PSTG Guideline / Contingency: CONTINGENCY #1 -LEVEL RESTORATION PSTG Section: C1 PSTG Step: C1-1 PSTG Statement: Line up for injection and start pumps in 2 or more of the following injection subsystems:
. Condensate ,
. LPCI A LPCI-B
. Core Spray-A
. Core Spray B l PSTG Justification:
Vermont Yankee doos not have a High Pressure Core Spray system. JDDA - 84 l _ _ - _ _ _ _ _ _ _ _ _ _ _ _ - _ _ _ _ _ . . _ _ _ _ _ _ _ _ _ _ _ _s____ _ _. a
JUSTIFICA N Justification for Deletion, Deviation, or Addition to the BWROG Emergency Procedure Guideline, Rev.3 (DEV. DEL, ADD) EPG Guldeline/ Contingency: CONTINGENCY #1 - LEVEL RESTORATION EPG Section: C1 EPG Step: C1-2 (cont.) EPG Statement: If less than 2 of the injection subsystems can be lined up, commence lining up as many of the following alternate injection subsystems as possible: [. RHR service water crosstie ] [+ SLC (boron tank) ] [. Fire system ) [. Interconnections with other systems ] [. ECCS keep-fill systems ] [ SLC (test tank) ] EPG Basis: If less than two of the injection subsystems listed in the first part of Step C1-2 can be lined up, alternate injection subsystems will be required to assure that water will be injected into the RPV following a blowdown. Included in the alternate injection subsystems are those systems and system interconnections capable of injecting water into the RPV but not normally utilized for this purpose because of low water quality or the relative difficulty of establishing the injection lineup 1 i PSTG Guldellne/ Contingency: CONTINGENCY #1 - LEVEL RESTORATION PSTG Section: C1 PSTG Step: C1-2 PSTG Statement: If less than 2 of the injection subsystems can be lined up with pumps running, but at least one Crste Spray subsystem can be lined up with suction from the suppression pool and the pump is running, SPRAY COOLING IS REQUIRED; enter (procedure developed from CONTINGENCY #4]. PSTG Justifleation: Because of the amount of time involved in lining up the alternate injection subsystems, as well as the fact that they are of low capacity and supply poor quality water, it was determined that if a core spray subsystem was available for spray cooling, this would be the preferable sequence. In this instance, the operator's time is better spent endeavoring to establish operability of primary injection subsystems while maintaining adequate core cooling via the Core Spray subsystem. This is, after all, its design l I basis (FSAR Section 6.5.2.4). The alternate injection subsystems are only utilized if the above PSTG step cannot be performed. l JDDA - 85 i
Justification for Deletion, Deviation, or Addition msmCA " E: DEL to the BWROG Emergency Procedure Guideline, Rev.3 (DEV, DEL, ADD) EPG Guldellne/ Contingency: CONTINGENCY #1 - LEVEL RESTORATON EPG Section: C1 EPG Step: C1-3 l EPG Statement: Monitor RPV pressure and water level. Continue in this procedure at the step indicated in the following table. RPV PRESSURE REGION [425 peig) [100 psig) RPV HIGH INTERMEDIATE LOW WATER INCREASING C14 C1-5 C1-6 LEVEL DECREASING C17 C1-8 EPG Basis: RPV water level trend and pressure are used to determine which specific actions are appropriate for restoration of RPV water level. The bases for these actions and their relationships to the parameters monitored is discussed under each step. PSTG Guldeline/ Contingency: CONTINGENCY #1 LEVELRESTORATON PSTG Section: C1 PSTG Step: n/a PSTG Statement: n/a PSTG Justifleation: Level restoration bases operator action upon the ability to maintain water level with whatever systems are available without regard to RPV pressure. If high pressure systems were incapable of maintaining level above TAF, or if level cannot be dntermined, the primary and/or alternate injection subsystems are lined up and pumps started. Suosequ! 7tly, the RPV is rapidly depressurized to maximize utilization of these low pressure injection subsystems. JDDA - 86 , 1 l _ _ _ _ _ _ _ . _ _ _ _ _ _ _ _ _ _ _ _ _ . _ _ o
Justification for Deletion, Deviation, or Addition JUSmCA " E: DEL to the BWROG Emergency Procedure Guideline, Rev.3 (DEV, DEL. ADD) EPG GuldelinelContingency: CONTINGENCY #1 LEVELRESTORATION EPG Section: C1 EPG Step: n/a l EPG Statement: If while executing the following step:
. The RPV water level trend reverses or RPV pressure changes region, return to [ Step C1-3].
EPG Basis: Different actions are required in Contingency #1 for different combinations of RPV pressure and water level trend. When plant conditions change sufficiently to drive one or these parameters across the boundaries of the table of Step C1=3, the actions which were specified for restoration of RPV water level may no longer be appropriate, and re-evaluation using the table is required. PSTG Guldellne/ Contingency: CONTINGENCY #1 -LEVEL RESTORATION PSTG Section: C1 PSTG Step: n/a PSTG Statement: n/a PSTG Justifleation: Vermont Yankee PSTG deleted EPG Step C1-3 (see JDDA for EPG Step C1-3). JDDA - 87
Justification for Deletion, Deviation, or Addition WS M N e: DEL to the BWROG Emergency Procedure Guideline, Rev.3 (DEV. DEL. ADD) EPG Guideline / Contingency: CONTINGENCY #1 - LEVEL RESTORATION EPG Section: C1 EPG Step: C1 -4 EPG Statement: RPV WATER LEVEL INCREASING, RPV PRESSURE HIGH Enter (procedure developed from the RPV Control Guideline] at [ Step RC/L]. EPG Basts: When RPV water level is increasing and RPV precra is above the shutoff head of low-head motor driven pumps, high-head pumps must be operating to restore RPV water level. Since RPV water level is increasing and no further action with respect to system initiation or RPV pressure control is required, the RPV water level control (RC/L) section of the RPV Control Guideline provides the appropriate steps for continued control of RPV water level. PST'G GuldelinelContingency: CONTINGENCY #1 - LEVEL RESTORATION PSTG Section: C1 PSTG Step: n/a PSTG Statement: n/a PSYG Justiflestion: Operators' knowledge of systems' behavior and training received on implementation of procedures based on these guidelines, together with the fact that level is increasing, sufficiently justifies deletion of this step. Specifically, the operators are trained to return to the procedure developed from RC/L, which provides the appropriate steps for continued control of RPV water level, once the entry condition to the procedure developed from this contingency no longer exists. Note that this contingency is entered from i RC/L when normal means of level control have failed (i.e., high head pumps) and level cannot be maintained above top of active fuel (TAF). l JDDA - 88 l - - - - - - _ _ _ - - - . - - - - - - . , )
JUSTIFICA N Justification for Deletion, Deviation, or Addition to the BWROG Emergency Procedure Guideline, Rev.3 I (DEV, DEL. ADD) EPG Guldeline/ Contingency: CONTINGENCY #1 LEVELRESTORATION EPG Section: C1 EPG Step: C15 l EPG Statement: RPV WATER LEVEL INCREASING, RPV PRESSURE INTERMEDIATE If HPCI and RCIC are not available and RPV pressure is increasing, EMERGENCY RPV DEPRESSURIZATION IS REQUIRED. When RPV pressure is decreasing, enter (procedure developed from the RPV Control Guideline] at [ Step RC/L]. If HPCI and RCIC are not available and RPV pressure is not increasing, enter [ procedure developed from the RPV Control Guideline) at [ Step RC/L]. EPG Basis: If RPV water level is increasing and steam-driven pumps are unavailable, motor-driven pumps must be operating to restore RPV water level. If RPV pressure is increasing, the injection flow rate from these pumps will decrease until, ultimately, RPV water level stops increasing and starts decreasing. If RPV pressure is constant or decreasing, the injection flow from these pumps will remain constant or increase. RPV water level control (RC/L) section of the RPV Control Guideline provides the appropriate steps for continued control of RPV water level under these circumstances. PSTG GuldelinelContingency: CONTINGENCY #1 -LEVEL RESTORATION PSTG Section: C1 PSTG Step: n/a PSTG Statement; n/a PSTG Justification: Since this contingency is entered from RC/L when normal means of level control have failed (i.e., steam-driven and/or motor driven high-head pumps) and level cannot be maintained above top of active fuel (T AF), it is assumed that water level can only be restored and maintained using low-head motor-driven pumps (i.e., primary and alternate injection subsystems). Subsequently, the RPV is rapidly depressurized to maximize utilization of these low pressure injection subsystems. The operators are trained to return to the procedure developed from RC/L, which provides the appropriate steps for continued control of RPV water level, once the entry condition to the procedure developed from this contingency no longer exists. This, together with the fact that level is increasing, su'ficiently justifies deletion of this step. JDDA - 89
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Justification for Deletion, Deviation, or Addition MEC N e: DEL to the BWROG Emergency Procedure Guideline, Rev.3 (DEV. DEL, ADD) EPG Guldeline/ Contingency: CONTINGENCY #1 LEVELRESTORATION EPG Section: C1 - EPG Step: C16 l EPG Statement: RPV WATER LEVEL INCREASING, RPV PRESSURE LOW If pressure is increasing, EMERGENCY RPV DEPRESSURIZATION IS REQUIRED. When RPV pressure is decreasing, enter (procedure developed from the RPV Control Guideline] at [ Step RC/L]. Otherwise, enter (procedure developed from the RPV Control Guideline) at [ Step RC/L). EPG Basis: If RPV pressure is below the low pressure isolation setpoint of steam-driven pumps and RPV water level is increasing, motor-driven pumps must be restoring RPV water level. Since RPV water level is increasing and no further action with respect to system initiation or RPV pressure control is required, the RPV water level control (RC/L) section of the RPV Control Guideline provides the appropriate steps for continued control of RPV water level. PSTG Guldeline/ Contingency: CONTINGENCY #1 LEVELRESTORATION PSTG Section: C1 lPSTG Step: n/a PSTG Statement n/a I e I PSTG Justification: Since this contingency is entered from RC/L when normal means of level control have failed (i.e., steam-driven and/or motor driven high head pumps) and level cannot be maintained above top of active fuel (TAF), it is assumed that water level can only be restored and maintained using low-head motor-driven pumps (i.e., primary and alternate injection subsystems). Subsequently, the RPV is rapidly depressurized to maximize utilization of these low pressure injection subsystems. The operators are trained to return to the procedure developed from RC/L, which provides the appropriate steps for continued control of RPV water level, once the entry condition to the procedure developed from this contingency no longer exists. This, together with the fact that level is increasing, sufficiently justifies deletion of this step. I JDDA - 90 _q- - .t
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JUSTIFICA N Justification for Deletion, Deviation, or Addition to the BWROG Emergency Procedure Guideline, Rev.3 (DEv. DEL ADD) EPG GuidellnelContIngency: CONTINGENCY #1 LEVELRESTORATION EPG Section: C1 EPG Step: C17 l EPG Statement: RPV WATER LEVEL DECREASING, RPV PRESSURE HIGH OR INTERMEDIATE if HPCI or RCIC is not operating, restart whichever is not operating. If no injection subsystem is lined up for injection with at least one pump running, start pumps in alternate injection subsystems which are lined up for injection. EPG Basis: If RPV pressure is above the low pressure isolation setpoint of steam driven pumps, either of these systems is not operating, and RPV water level is decreasing, the non-operating system should be restarted to maximize the injection flow into the RPV. If RPV water level is decreasing and no injection subsystem is operating, injection from alternate injection subsystems is required to reverse the RPV water level trend. PSTG Guldellne/ Contingency: CONTINGENCY #1 -LEVEL RESTORATION PSTG Section: C1 PSTG Step: n/a PSTG St a te r.9 ent : n/a l I PSTG Justification: Since this contingency is entered from RC/L when normal means of level control have failed (i.e., i steam-driven and/or motor-driven high-head pumps) and level cannot be maintained above top of active l fuel (TAF), it is assumed that water level can only be restored and maintained using low-head motor-driven pumps (i.e., primary and alternate injection subsystems). Subsequently, the RPV is rapidly depressurized to maximize utilization of these low precsure injection subsystems. If primary and alternate injection subsystems are not available, and if at least one core spray subsystem is not available, then the operator would be directed to initiate steam cooling (Contingency #3). JDDA - 91 l . . _ a
JUSTIFICA N Justification for Deletion, Deviation, or Addition to the BWROG Emergency Procedure Guidelino, Rev.3 (DEV. DEL. ADD) EPG GuldelinelContingency: CONTINGENCY #1 LEVELRESTORATION EPG Section: C1 EPG Step: C17 (continued) l EPG Statement: RPV WATER LEVEL DECREASING, RPV PRESSURE HIGH OR INTERMEDIATE When RPV water level drops to [-164 Irs. (top of active fuel)]: If no system, injection subsystem or alternate injection subsystem is lined up with at least one pump running, STEAM COOLING IS REQUIRED. When any system, injection subsystem or alternate injection subsystem is lined up with at least one pump running, return to (Step C13]. EPG Basis: If the decreasing RPV water level trend has not reversed before RPV water level drops to the top of active fuel and no source of injection into the RPV is available, the only mechanism by which adequate core cooling can be assure is Steam Cooling. When a source of injection into the RPV becomes available, the steps of Contingency #3 (Steam Cooling), which are executed concurrently with this step in Contingency #1, require RPV depressurization to maximize the injection flow rate from the operating pumps. PSTG GuldellnelContingency: CONTINGENCY #1 LEVELRESTORATION PSTG Section: C1 PSTG Step: C14, C15 PSTG Statement: C1-4: If no system, injection subsystem or alternate injection subsystem is lined up with at least one pump running, STEAM COOLING IS REQUIRED; enter (Procedure developed from CONTINGENCY #3) and execute it concurrently with this procedure. C15: When any system, injection subsystem or alternate injection subsystem is lined up with at least one pump running, enter [ Procedure developed from CONTINGENCY #2]. PSTG Justification: If primary and alternate injection subsystems are not available, and if at least one core spray subsystem is not available, then the operstor would be directed to initiate steam cooling (Contingency
#3). Subsequent recovery of any system, injection subsystem or alternate injection subsystem, which is lined up with at least one pump running, the RPV would then be rapidly depressurized to maximize utilization of these low pressure injection subsystems.
As stated in the JDDA for EPG Step C1-3, level restoram bases operator action upon the ability to maintain water level with whatever systems are available without regard to RPV pressure. JDDA - 92 E_____________________________________________________n- - e.
JUSTIFICA N Justification for Deletion, Deviation, or Addition to the BWROG Ernergency Procedure Guideline, Rev.3 (DEV. DEL. ADD) EPG Guideline / Contingency: CONTINGENCY #1 - LEVEL RESTORATION EPG Section: C1 l EPG Step: C1 -8 EPG Statement: RPV WATER LEVEL DECREASING, RPV PRESSURE LOW [lf no HPCS or LPCS subsystem is operating,] start pumps in alternate injection subsystems which are lined up for injection. If RPV pressure is increasing, EMERGENCY RPV DEPRESSURIZATION IS REQUIRED, When RPV water level drops to [-164 in. (top of active fuel)], enter (procedure developed from CONTINGENCY #4). EPG Basis: If RPV pressure is below the isolation setpoint of steam-driven pumps, only motor-driven pumps are available for injection Inot the RPV. If the decreasing RPV water level trend is not reversed before RPV water level drops to the top of active fuel, spray cooling (Contingency #4) becomes the best method for continued assurance of adequate core cooling. PSTG Guidellne/ Contingency: CONTINGENCY #1 -LEVEL RESTORATION PSTG Section: C1 PSTG Step: C1-2 PSTG Statement: if less than 2 of the injection subsystems can be lined up with pumps running, but at least one Core Spray subsystem can be lined up with suction from the suppress lon pool and the pump is running, SPRAY COOLING IS REQUIRED; enter (Procedure developed from CONTINGENCY #4). PSTG Justifleation: Because of the amount of time involved in lining up the alternate injection subsystems, as well as the fact that they are of low capacity and supply poor quality water, it was determined that if a core spray subsystem was available for spray cooling, this would be the preferable sequence (see JJDA for EPG Step C1-2). Emergency RPV depressurization will be accomplished via PSTG Step C41. Note that this contingency is entered from RC/L when normal means of level control have failed (i.e., steam-driven and/or motor-driven high head pumps) and level cannot be maintained above top of active fuel (TAF). JDDA - 93 _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ ._. - _ _ _ _ _ _ < n
JUSTIFICA N Justification for Deletion, Deviation, or Addition to the BWROG Emergency Procedure Guideline, Rev.3 (DEV, dei ADO) EPG Guldeline/ Contingency: CONTINGENCY #2 - EMERGENCY RPV DEPRESSURIZATION EPG Section: C2 EPG Step: C2-1 EPG Statement: I When either: Boron injection is required and all injection into the RPV except from boron injection systems and CRD has been terminated and prevented, or
. Boron Injection is not required EPG Basis:
Prior to conducting RPV depressurization in accordance with the steps of Contingency #2, consideration must first be given as to whether Boron Injection is required. When Boron injection is required, failure to terminate and prevent injection into the RPV (except from boron injection systems and CRD) may result in the rapid injection of large volumes of relatively cold, unborated water from low pressure systems as RPV pressure decreases and drops below the shutoff heads of the pumps in these systems. When Boron Injection is required, Step C21 does not contain explicit instructions for terminating and preventing injection into the RPV but rather relies upon steps in Contingency #7 to be completed. PSTG Guldeilne/ Contingency: CONTINGENCY #7 - EMERGENCY RPV DEPRESSUR(ZATION PSTG Section: C2 PSTG Step: C2-1/C2-2 PSTG Statement: C2-1: If all control rods are inserted to or beyond position 02 (maximum subcritical banked rod withdrawal position): C2-2: If all control rods are not inserted to or beyond position 02 (maximum suberitical banked rod withdrawal position), terminate and prevent all injection into the RPV except boron and CRD. PSTG Justification: Rather than risk dilution of the boron concentration and reduction of water temperature in the core region, thereby adding sufficient net positive reactivity and inducing a reactor power excursion which could damage the core, a more conservative approach is taken. That is tha requirement the reactor be shut down by rod insertion, with all rods inserted to or beyond the maximum subcritical banked rod withdrawal position. The maximum suberitical banked withdrawal position is defined to be the maximum i control rod position to which all control rods can be withdrawn and the reactor remain in a cold l (typically 70 *F) shutdown condition at the most reactive time in core life. l I Since Vermont Yankee has not implemented EPG Contingency #7 (see JDDA), the instructions to the operator for termination and prevention of all injection into the RPV with the exception of boron and CRD is contained here. JDDA - 94 1
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msmC ON Justification for Deletion, Deviation, or Addition pe: ADD to the BWROG Emergency Procedure Guideline, Rev.3 (DEV. DEL. ADD) EPG Guldeline/ Contingency: CONTINGENCY #2 EMERGENCY RPV DEPRESSURIZATION EPG Section: C2 EPG Step: n/a l EPG Statement: n/a i EPG Basis: n/a PSTG Guideline / Contingency: CONTINGENCY #7 - EMERGENCY RPV DEPRESSUR(ZATION PSTG Section: C2 lPSTG Step: C21.1 & C2-1.2 PSTG Statement: C2-1.1: If the MSIVs are open and the main condenser is availabe:
. Open a minimum of 5 Bypass valves C2-1.2:
If less than 5 (Minimum Number of Turbine Bypass Valves Required for Emergency Depressurization) Bypass valves are open procede to [ Step C2-2.1) PSTG Justification: The prefered method for rapidly reducing RPV pressure is to discharge steam to the main condenser via the main turbine bypass valves. The minimum of five bypass valves is specified since for Vermont Yankee, the capacity of five bypass valves is approximately equal to that of all four ADS valves. We believe that the advantages of using the main condenser instead of the suppression pool as a heat sink outweigh the delay associated with manual opening of the bypass valves. This time differential of less than one second for the opening of the relief valves verses approximately 40 seconds for the opening of the five bypass valves, is judged to be less significant than the potential, additional complications involved with discharging to the torus. This judgement is based on the fact that the time required to fully depressurize the RPV is not significantly increased. JDDA - 95 o a
JUSTIFICA Justification for Deletion, Deviation, or Addition to the BWROG Emergency Procedure Guideline, Rev.3 (DEV. DEL. A00) EPG Guldeline/ Contingency: CONTINGENCY #2 EMERGENCY RPV DEPRESSURIZATION EPG Section: C2 EPG Stept C2 1.1 l EPG Statement: initiate 10. 1 EPG Basis: Isolation condenser (IC) initiation effects a prompt reduction in RPV pressure without a loss of coolant inventory and without heat addition to the suppression pool. Initiation of the isolation condenser is generally a quick and easily performed task. PSTG Guldeline/ Contingency: CONTINGENCY #7 - EMERGENCY RPV DEPRESSURl2ATION PSTG Section: C2 PSTG Step: n/a PSTG Statement: n/a PSTG Justifleation: Vermont Yankee does not have an isolation condenser JDDA - 96 _ _ - - - _ _ _ _ _ _ _ _ _ _ _ _ _ - _ _ _ _ _ _ _ _ _ - _ _ .n_ _ n.
JUSTIFICA Justification for Deletion, Deviation, or Addition to the BWROG Emergency Procedure Guideline, Rev.3 (DEv. DEL A00) EPG Gutdeline/ Contingency: CONTINGENCY #2 - EMERGENCY RPV DEPRESSURIZATION EPG Section: C2 EPG Step: C 2-1.1 EPG Statement: If suppression pool water level is above (4 ft. 9 in. (elevation of top of SRV discharge device)):
. Open all ADS valves If any ADS valve cannot be opened, open other SRVs until [7 (number of SRVs dedicated to ADS)] valves are open.
EPG Basis: The objective of Contingency #2 is to depressurize the RPV as rapidly as possible within the limitations of the plant. Depressurization of the RPV is most easily and rapidly accomplished by opening SRVs; thus instructions for operation of these valves are specified first, in preference to steps for use of other depressurization systems and mechanisms. Of the SRVs, those assigned to ADS function are most reliable because of their qualifications, their pneumatic supply systems, etc. If one or more ADS valves cannot be opened, other SRVs (as available) should be opened until the total number of open SRVs equals the number of SRVs dedicated to the ADS function. PSTG Gulde11ne/ Contingency: CONTINGENCY #7 - EMERGENCY RPV DEPRESSURIZATION t PSTG Section: C2 PSTG Step: C2-2.1 PSTG Statement: If suppression pool water level is above 6 ft. (elevation of top of SRV discharge device): Open all SRVs PSTG Justifleation: Vermont Yankee does not have any other SRVs which the operator can open. All four (4) SRVs are dedicated to the ADS. JDDA - 97
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l l JUSTIFICA N Justification for Deletion, Deviation, or Addition to the BWROG Emergency Procedure Guideline, Rev.3 (DEV. DEL, ADO) EPG GuldelinelContingency: CONTINGENCY #2 EMERGENCY RPV DEPRESSURIZATION l EPG Section: C2 EPG Step: C2 1.3 l EPG Statement: If less than [3 (Minimum Number of SRVs Required for Emergency Depressurization)] SRVs are open [and RPV pressure is at least 50 psig (Minimum SRV Re-opening Pressure) above suppression chamber pressure], rapidly depressurize the RPV using one or more of the following systems (use in order which will minimize radioactivity release to the environment):
. Main condenser . Main steam line drains . Head vent
. RHR (steam cooling mode) . HoCl steam line . IC tube side vent
. [Other steam driven equip.] . RCIC steam line EPG Basis:
The minimum number of SRVs required for emergency RPV depressurization is that number which restricts peak cladding temperature to less than 2200 'F during any design-basis loss of coolant accident (LOCA) when calculated using realistic assumptions regarding decay heat, etc. A list of alternate systems is included to be used in the order which will minimize the release of radioactivity to the environment. However, since plant conditions cannot be known in advance, specific priorities regarding system use cannot be pre-assigned. The main condenser is generally the preferred heat sink if the main steam lines are intact. PST'G GuldelinelContingency: CONTINGENCY #7 EMERGENCY RPV DEPRESSURIZATION PSTG Section: C2 PSTG Step: C2-2.2 PSTG Statement: If less than 3 (Minimum Number of SRVs Required for Emergency Depressurization) SRVs are open and RPV pressure is at least 50 psig (Minimum SRV Re opening Pressure) above suppression chamber pressure, rapidly depressurize the RPV using one or more of the following systems:
. Turbine Bypass valves . RPV head vent
. Main steam line drains
. HPCI steam line
. RCIC steam line PSTG Justification:
The list of alternate systems does not include RHR (steam cooling mode), other steam driven equipment, or the IC tube side vent because Vermont Yankee is not equipped with these systems / modes of operation. With the exception of the turbine bypass valves / main steam lines, these alternate depressurization systems are of very limited capacity or discharge into primary containment (i.e., HPCI steam lines). Because of this, and also because the main steam line high radiation isolation would not be bypassed, l there is no requi ement regarding minimization of release of radioactivity. JDDA -98
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ESMCA N Justification for Deletion, Deviation, or Addition e DEL to the BWROG Emergency Procedure Guideline, Rev.3 (DEV, DEL ADD) EPG Guideline / Contingency: CONTINGENCY #3 - STEAM COOLING EPG Section: C3 EPG Step: C31 l EPG Statement: Confirm initiation of IC. EPG Basis: Isolation condenser (IC) operation establishes a closed flowpath for core cooling. Steam flows through the core to the isolation condenser where it is condensed, and the condensato is returned to the RPV. In this manner the core may be cooled for an extended period of time with no loss of coolant inventory or requirement for inventory makeup to the RPV. PSTG Guideline / Contingency: CONTINGENCY #3- STEAM COOLING PSTG Section: C3 PSTG Step: n/a PSTG Statement n/a PSTG Justification: Vermont Yankee does not have an isolation condenser. JDDA 99
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JUSTIFICA N Justification for Deletion, Deviation, or Addition to the BWROG Emergency Procedure Guideline, Rev.3 (DEV. DEL. ADD) l EPG GuldelinelContingency: CONTINGENCY #3 - STEAM COOLING EPG Section: C3 EPG Step: C3-1 EPG Statement: If IC cannot be initiated: When RPV water level drops to [-272 in. (Minimum Zero-Injection RPV Water Level)] or if RPV water level carniot be determined, open one SRV. EPG Basis: If the isolation condenser (IC) cannot be initiated, steam cooling is initiated by allowing RPV water level to decrease through boil-off until it drops to the Minimum Zero-Injection RPV Water Level, at which point peak cladding temperature will have reached approximately 2000 F. One SRV is then opened to provide adequate steam cooling with the RPV at high pressure. PSTG Guideline / Contingency: CONTINGENCY #3 - STEAM COOLING PSTG Section: C3 g PSTG Step: C3-1 PSTG Statemsni; When RPV water level drops to -87 in. (Minimum Zero-Injection RPV Water Level) or if RPV water level cannot be determined, open one SRV. PSTG Justifleation: Reference to the isolation condenser was deleted since Vermont Yankee does not have an 10. l 1 i JDDA - 100 - _ _ _ _ _ _ . _ _ _ _ _ .s n
JUSTIFICA N Justification for Deletion, Deviation, or Addition to the BWROG Emergency Procedure Guideline, Rev.3 (DEV, DEL. ADD) EPG Guldeline/ Contingency: CONTINGENCY #3 STEAMCOOLING EPG Section: C3 EPG Step: n/a l EFG Statement: n/a EPG Basis: n/a PSTG GuldelinelContingency: CONTINGENCY #3 STEAMCOOLING PSTG Section: C3 l PSTG Step: C3-1 PSTG Statement: Reference to Caution #31 "Contro! Room indication of the following parameters are subject to instrument error:
. Drywell tempererature +/- 10 *F Reactor pressure +/- 40 psi" PSTG Justification:
This caution was added since the operator is directed to perform an action based upon RPV pressure. Therefore, it was deemed necessary that the magnitude of instrument inaccuracy for post accident conditions be included within the procedure. 1 (reference: Memo, M.E. Palionis to D.E. LaBarge, " Addition of Caution to Emergency Operating , Procedures, dated 6/20/86) J JDDA - 101 - - _ _ _ _ _ - _ - _ - _ - _ _ _ _ _ _ _ _ _ _ _ _ _ ._. _a
Justification for Deletion, Deviation, or Addition ame " E: DEV to the BWROG Ernergency Procedure Guideline, Rev.3 (DEV. DEL. ADD) EPG Guldeline/ Contingency: CONTINGENCY #4 - CORE COOLING WITHOUT LEVEL RESTORATION EPG Section: C4 EPG Step: C4-1 EPG Statement: Open all ADS valves. If any ADS valve cannot be opened, open other SRVs until[7 (number of SRVs dedicated to ADS)] valves are open. EPG Basis: Even though Contingency #4 is entered with RPV pressure below the shutoff head of low pressure injection systems, all ADS valves are opened to ensure that the RPV remains depressurized throughout core spray operation. This minimizes the head which the core spray system pump (s) must overcome and assures that sufficient spray flow and adequate spray distribution ara maintained. Because RPV pressure is below the LPCS shutoff head when Contingency #4 is entered, taking time to align alternate depressurization systems (identified in Contingency #2) is not warrented even if the number of SRVs dedicated to ADS cannot be opened. PSTG Guldellne/ Contingency: CONTINGENCY #4 - CORE COOLING WITHOUT LEVEL RESTORATION PSTG Section: C4 PSTG Step: C4-1 PSTG Statement: If at least one core spray subsystem is lined up with suction from the suppression pool and a pump running, perform EMERGENCY RPV DEPRESSURIZATION; enter [ procedure developed from Contingency
#2) and execute it concurrently with this procedure.
PSTG Justificotlen: The conditions for entry into this contingency, as established in PSTG Contingency #1, are re-iterated for clarity. Further, entry into PSTG Contingency #4 does not require that RPV pressure be below the core spray shutoff head, nor can it be assumed that pressure will remain below the shutoff head while spraying the core. For these reasons, and to ensure maximization of core spray flow, entry into Contingency #2 is specified. JDDA 102 _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ w a
ESER N Justification for Deletion, Deviation, or Addition DEV e: to the BWROG Ernergency Procedure Guideline, Rev.3 (DEV. del ADD) EPG Guldeline/ Contingency: CONTINGENCY #4 - CORE COOLING WITHOUT LEVEL RESTORATION EPG Section: C4 EPC Step: C4-2 ' EPG Statement: Operate HPCS and LPCS subsystems with suction from the suppression pool. When at least one core spray subsystem is eporating with suction from the suppression pool and RPV pressure is below [310 psig (RPV pressure for rated LPCS or HPCS flow, whichever pressure is lower)], terminate injection into the RPV from sources external to the primary containment. EPG Basis: Either HPCS or LPCS may be used to provide core spray flow. Engineering analysis hase verified that the core remains adequately cooled with one core spray subsystem operating at or above the design flow rate and with adequate spray distribution. Core spray suction is aligned to the suppression pool so that the primary coolant flowpath is contained entirely within the boundary of Ine primary containment. Injection into the RPV from pumps taking suction from sources other than the suppression pool is terminated to prevent continued increase in suppression pool water level, which avoids the increased containment loads resulting form high suppression pool water level. PSTG Guldellne/ Contingency: CONTINGENCY #4 CORE COOLING WITHOUT LEVEL RESTORATION PSTG Section: C4 PSTG Step: C4-1 PSTG Statement: Operate Core Spray subsystem (s) with suction from the suppression pool. When RPV pressure is below 120 psig (RPV pressure for rated Core Spray flow), terminate injection from sources external to the primary containment except boron injection and CRD. PSTG Justification: Since Vermont Yankee does not have a HPCS, reference to this system is deleted. PSTG Step C4-1 established that at least one core spray subsystem is operating, tnerefore there is no need to confim this. Boron injection systems and CRD were excepted from the list of sources taking suction outside the primary containment since they may be necessary to establish reactor power control per section RC/O of the EPGs/PSTGs. JDDA - 103 t
- JUSTIFICA N Justification for Deletion, Deviation, or Addition to the BWROG Emergency Procedure Guideline, Rev.3 (DEV. DEL. ADD)
EPG Guldeline/ Contingency: CONTINGENCY #4 CORE COOLING WITHOUT LEVEL RESTORATION EPG Section: C4 EPG Step: C4-2 l EPG Statement: n/a EPG Basis: n/a PSTG Guldeline/ Contingency: CONTINGENCY #4 CORE COOLING WITHOUT BEL RESTORATION PSTG Section: C4 PSTG Step: C41 PSTG Statement: Reference to Caution #31 " Control Room indication of the following parameters are subject to instrument error:
. Drywell tempererature +/- 10 *F
+ Reactor pressure +/- 40 psi" PSTG Justifleation:
This caution was added since the operator is directed to perform an action based upon RPV pressure. i Therefore, it was deemed necessary that the magnitude of instrument inaccuracy for post. accident ! conditions be included within the procedure. (reference: Memo, M.E. Palionis to D.E. LaBarge, " Addition of Caution to Emergency Operating Procedures, dated 6/20/86) JDDA - 104
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JUSTIFICA N j Justification for Deletion, Deviation, or Addition to the BWROG Ernergency Procedure Guideline, Rev.3 (DEV. DEL. ADD) EPG Guideline / Contingency: CONTINGENCY #6-RPV FLOODING EPG Section: C6 EPG Step: C61 l EPG Statement: If at least [3 (minimum number of SRVs required for Emergence Depressurization)) SRVs can be opened or if HPCS or motor driven feedwater pumps are available for injection, close the MSIVs, main steam line drain valves, IC, HPCI, RCIC and RHR steam condensing isolation valves. EPG Basis: If the number of SRVs that are open is 2 the min. num. of SRVs required for emerg depressurization, there is reasonable assurance that the RPV will remain depressurized during the flooding evolution. It is then appropriate to isolate all steam lines to preclude damage to steam driven equipment and piping. If HPCS or motor driven FW pumps are available, these valves may be closed since these high-head pumps are capable of flooding the RPV at high pressure. The condition precedent for this step is based upon how many SRVs can be opened vs. how many are opened. This reflects the procedural sequence which requires that the operator endeavor to open SRVs in Cont. #2 prior to completing this step. PSTG Guldellna/ Contingency: CONTINGENCY #6- RPV FLOODING PSTG Section: C6 PSTG Step: C6-2 PSTG Statement: If at least (3 (minimum number of SRVs required for Emergence Depressurization)) SRVs can be opened or motor driven feedwater pumps are available for injection, close the MSIVs, main steam line drain valves, HPCl, and RCIC isolation valves. PSTG Justification: 1 Since PSTG Contingency #6 is only entered via the emergency depressurization contingency, conditions are already established for RPV ficoding. However, PSTG Contingency #6 has more clearly defined the operator actions as relating to control rod position. Thorefore, if all control rods are inserted to or j beyond position 02, PSTG step C6 2 applies. Otherwise, step C61 is executed (see JDDA for PSTG j C 6 - 1.1 ) . {I Vermont Yankee does not have either a HPCS or an RHR Steam Condensing mode of operation for the RHR l system. Therefore, these were deleted from the list of systems. = JDDA 106 l
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i WSE CA N Justification for Deletion, Deviation, or Addition e: DEL to the BWROG Emergency Procedure Guideline, Rev.3 (DEV. DEL. ADD) EPG Guideline / Contingency: CONTINGENCY #6 - RPV FLOODING EPG Section: C6 EPG Step: C 6-2.1 EPG Statement: Terminate and prevent all injection into the RPV except from boron injection systems and CRD until RPV pressure is below the Minimum Alternate RPV Flooding Pressure. If less than [1 (minimum number of SRVs for which the Minimum Alternate RPV Flooding Pressure is below the lowest SRV lifting pressure)] SRV[s] can be opened, continue in this procedure. EPG Basis: Before the RPV is flooded it should, if possible, be dnressurized. However, a rapid depressurization of the RPV may result in the rapid injection of large volumes of relatively cold, unborated water from low pressure injection systems. Thus all injection into the RPV must be terminated and prevented prior to commencing the rapid depressurization. Injection from boron injection systems and CRD is not terminated here because boron injection systems add negative reactivity and CRD is required to manually insert control rods. PSTG Guldeline/ Contingency: CONTINGENCY #6 - RPV FLOODING PSTG Section: C6 PSTG Step: C6 1.1 l PSTG Statement: If open, close the following valves:
- MSIVs
. Main Steamline drain valves When RPV pressure falls below the Minimum Alternate Flooding Pressure, continue in this procedure.
PSTG Justification: As noted in the JDDA to EPG C6-1, the PSTG Contingency #6 is only entered after RPV depressurization per Contingency #2 has been performed. PSTG Contingency #2 has the above operator action contained in EPG step C6-2.1 added to preclude the rapid injection of large volumes of relatively cold, unborated water, from either high or low pressure injection systems. Isolation of the steam line valves is performed since the basis for the Minimum Alternate Flooding Pressure (MAFP) table is based on having adequate steam flow through the core at the MAFP for a given number of open SRVs. If flow was directed down the main steam lines, Ws table would not be the appropriate guideance for operator actions. The final statement in EPG step C6-2.1 is not included since the operator would cominue in this procedure if no SRVs (i.e., less than one) were open. JDDA - 106 - _ - _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ m o
l JUSMC Justification for Deletion, Deviation, or Addition DEL E: to the BWROG Emergency Procedure Guideline, Rev.3 : (oev.oet. Aco) j l l EPG GuldelinelContIngency: CONTINGENCY #6 - RPV FLOODING EPG Section: C6 EPG Step: C6 2.2 EPG Statement: If while executing the following step, RPV water level can be determined and RPV flooding is not required, enter [ procedure developed from Contingency #7] and [ procedure developed from the RPV Control Guideline) at [ Step RC/P 4] and execute these procedures concurrently. EPG Basis: Under these conditions, if RPV water level can be determined and RPV Flooding is no longer required for any other reason, the steps appropriate for control of RPV water level are provided in Contingency #7 and Contingency #6 should therefore be exited. Steps appropriate for control of RPV pressure are likewise provided in the RPV pressure control (RC/P) section of the RPV Control Guideline. 1 PSTG GuldelinelContIngency: CONTINGENCY #6 RPV FLOODING PSTG Section: C6 PSTG Step: C6-1.3 PSTG Statement: If RPV level can be maintained above TAF and RPV Flooding is not required, enter [ procedure developed from RPV Control Guideline] at [ Step RC/L-1). PSTG Justification: If the conditions which existed that required entry into the RPV Flooding contingency no longer exist, - i.e., low RPV water level - than this contingency is exited and the operator is directed to enter the RPV level control (RC/P) section of the RPV Control Guideline. As noted previously, Verment Yankee does not implement Contingency #7. As noted in the JDDA for EPG Step C3-1 (Level Restoration), level restoration bases operator action upon the ability to maintain water level with whatover systems are available without regard to RPV pressure. If high pressure systems were incapable of maintaining level above TAF, or if level cannot be determined, the primary and/or alternate injection subsystems are lined up and pumps started. Subsequently, the RPV is rapidly depressurized to maximize utilization of these low pressure injection subsystems. JDDA 107 . _ _ . _ _ - _ - _ _ _ _ _ _ _ _ _ __ ._____. _. A_ ?
JUSTIFICA N Justification for Deletion, Deviation, or Addition to the BWROG Emergency Procedure Guideline, Rev.3 (DEV. DEL A00) EPG Guideline / Contingency: CONTINGENCY #6 - RPV FLOOCMG EPG Section: C6 EPG Step: C6-2.2 EPG Statement: Commence and slowly increase injection into the RPV with the following systems until at least [1 (minimum number of SRVs for which the Minimum Alternate RPV Flooding Pressure is below the lowest SRV lifting pressure)) SRV[s] is open and RPV pressure is above the Minimum Alternate RPV Flooding Pressure:
. Motor driven feedwater pumps [ LPCI)
Condensate pumps
.CRD EPG Basis:
Re-establishing injection into the RPV having terminated it in Step C6 2.1 is required to adequately cool the core and ultimately flood the RPV. Injection is increased slowly to preclude the possibility of large power excursions due to rapid injection of relatively cold, unborated water. Injecting at a rate sufficient to maintain RPV pressure above the Minimum Alternate RPV Flooding Pressure assures that either the RPV will flood to the main steam lines or, if the reactor returns to criticality, the core will be adequately cooled by a combination of submergence and steam cooling. The systems identified are those motor-driven pumps injecting outside the shroud. PSTG Guideline / Contingency: CONTINGENCY #6 - RPV FLOODING PSTG Section: C6 PSTG Step: C6-1.2 PSTG Statement: Commence and slowly increase injection into the RPV with the following systems:
. Feedwater pumps . Condensate pumps .CRD RCIC .HPCI LPCI until any one of the following conditions is stisfied:
. reactor power increases and continues to increase or,
. at least one SRV can be opened and RPV pressure is above the MAFP, or RPV level can be maintained above TAF PSTG Justification:
RCIC and HPCI were added since the minimum alternate flooding pressures would, in most cases, permit their useage, and because they may be the only methods available for injection into the RPV which inject outside the shroud. To preclude large power excursions due to cold, unborated water injection, the condition " reactor power increases and continues to increase" was added. This is in agreement with Caution #25 which is applied to this step: "A rapid increase in injection into the RPV may induce a large power excursion and result in substantial core damage". This establishes the criteria for control of injection flow. The conditicn "RPV level can be maintained above TAF" was included since this would satisfy the criteria for adequate cooling of the core (i.e., submergence). Continued floedup of the RPV is conducted per subsequent steps of this contingency (see JDDA for EPG step C6 2.2, re: continued floodup). JDDA - 108 - _ _ _ _ _ _ _ _ _ _ _ . _ _ _ _ _ . a
Justification for Deletion, Deviation, or Addition msme " E: DEV to the BWROG Emergency i f op*1ure GJide"ne, Rev.3 (DEV. DEL A00) EPG GuldelinelContingency: CONTINGENCY #6-RPV FLOODING EPG Section: C6 EPG Step: C6-2.2 (continued) l EPG Statement: If at least [1 (minimum number of SRVs for which the Minimum Alternate RPV Flooding Pressure (MAFP) is below the lowest SRV lifting pressure)) SRV[s] are not open or RPV pressure cannot be increased to above the MAFP, commence and slowly increase injection into the RPV with the following systems until at least [1 ( minimum number of SRVs for which the Minimum Alternate RPV Flooding Pressure (MAFP) l is below the lowest SRV lifting pressure)) SRV[s] are open and RPV pressure is above tne MAFP:
.HPCS .LPCS [. RHR service water crosstie] [ Fire system]
[. Interconnection with other units] [. ECCS keep-fill systems) EPG Basis: If RPV pressure cannot be maintained above the MAFP using preferred systems, alternate systems must also be employed. These systems either inject inside the shroud, are designed and constructed to less stringent standards, or take suction on sources with comparatively lower water quality. PSTG Guldeline/ Contingency: CONTINGENCY #6 - RPV FLOODING PSTG Section: C6 PSTG Step: C6-1.2 (continued) PSTG Statement: If none of the above conditions are satisfied, commence and slowly increase injection into the RPV with the following systems until at least one of the above conditions is satisfied:
. Core Opray
. RHR service water
. Fire System PSTG Justifleation:
Rather than restate the conditions enumerated in the first part of this step, they are simply referred to. Since Vermont Yankee doesn't have a HPCS or interconnections with other units, these were deleted. The ECCS keep-fill system at Vermont Yankee is of very small capacity, and was therefore not included i in this listing. , I l l JDDA - 109
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i l JUSTIFICA N Justification for Deletion, Deviation, or Addition I to the BWROG Emergency Procedure Guideline, Rev.3 (DEV, DEL ADD) 1 EPG Guldeline/ Contingency: CONTINGENCY #6 RPVFLOODING EPG Section: C6 EPG Step: C 6-2.4 EPG Statement: When: All control rods are inserted beyond position [06 (maximum suberitical banked withdrawal rod position)], or
. The reactor is shut down and no boron has been injected into the RPV, continue in this procedure.
EPG Basis: When either of the two conditions specified in this step are satisfied, the reactor is shutdown and will remain shutdown with the RPV in the flooded condition. Under these conditions it is appropriate to continue in this procedure at Step C6-3 or C6-4, which specify the actions required to flood a shutdown reactor when the addition of cold, unborated water is not a concern. PSTG Gulcieline/ Contingency: CONTINGENCY #6 - RPV FLOODING PSTG Section: C6 PSTG Step: C6-1.4 PSTG Statement: When all control rods are inserted to or beyond position 02 (maxim Jm subcritical banked wi'hdrawal rod position), continue in this procedure. PSTG Justifiestion: The inability of the average operator to determine whether or not the reactor will remain shut down during the succeeding steps as well as the added conservatism requiring that all rods be inserted to or beyond the maximum suberitical banked withdrawal rod position justifies this deviation. JDDA - 110
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JUSTlFICA N Justification for Deletion, Deviation, or Addition to the BWROG Emergency Procedure Guideline, Rev.3 (DEV. DEL. ADD) EPG Guldeline/ Contingency: CONTINGENCY #6 RPVFLOODING EPG Section: C6 EPG Step: C6 5.1 l EPG Statement: {lf RPV water level cannot be determined: Fill all RPV water level instrumentation reference columns. EPG Besis: n/a PSTG Guldeline/ Contingency: CONTINGENCY #6- RPV FLOODING PSTG Section: C6 lPSTG Step: n/a PSTG Statement: n/a PSTG Justification: If RPV water level cannot be determined, operations personnel would 5itiate a maintenance request to determine if the problem lies with the level instrumentation. Part of the work scope conducted by the repair department, under the direction from the Technical Support Center (TSC) would be to investigate not only the reference legs, but also instrument power supplies, system piping integrity, etc. JDDA - 111
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JUSTIFICA N Justification for Deletion, Deviation, or Addition to the BWROG Emergency Procedure Guideline, Rev.3 (DEV. DEL. ADO) EPG . GuldelinelContIngency: CONTINGENCY #6 RPVFLOODING EPG Section: C6 EPG Step: C 6-5.2 l EPG Statement: n/a EPG Basis: n/a PSTG Guideline / Contingency: CONTINGENCY #6- RPV FLOODING PSTG Section: C6 PSTG Step: C6-5.1 PSTG Statement: Reference to Caution #31 " Control Room indication of the following parameters are subject to instrument error:
- Drywell tempererature +/ 10 *F
- Reactor pressure +/ 40 psi' PSTG Justification:
This caution was added since the operator is directed to perform an action based upon drywell temperature. Therefore, it was deemed necessary that the magnitude of ir.strument inaccuracy for post-accident conditions be included within the procedure. (reference: Memo, M.E. Palionis to D.E. LaBarge, " Addition of Caution to Emergency Operating l Procedures, dated 6/20/86) JDDA - 112 n n
JUSTIFICATA N Justification for Deletion, Deviation, or Addition to the BWROG Emergency Procedure Guideline, Rev.3 (DEV, DEL. ADD) EPG GuldelinelContIngency: CONTINGENCY #6 - RPV FLOODING EPG Section: C6 EPG Step: C6 5.3 EPG Statement: if it can be determined that the RPV is filled or if RPV pressure is at least [77 psig (Minimum RPV Flooding Prusure)] above suppression chamber pressure, terminate all injection into the RPV and reduco RPV water level. EPG Basis: If the RPV is flooded or being flooded and RPV water level instrumentation becomes available, the water level must be reduced to bring the instrumentation on scale and to verify that the water level instrumentation is correctly trending. Termination of injection and reduction in RPV water level may threaten adequate core cooling if prolonged. Thus a time limit is placed on this evolution to assure adequate core cooling under these c rcumstances (i.e., Maximum Core Uncover Time Limit). PSTG Guideline / Contingency: CONTINGENCY #6 - RPV FLOODING PSTG Section: C6 PSTG Step: C6-5.2 PSTG Statement: If it can be determined that the RPV is filled or if RPV pressure is at lent 50 psig (Minimum RPV Flooding Pressure) above suppression chamber pr.cssure:
. determine the Maximum Acceptable Core Uncovery Time
+ terminate all injection into the RPV and allow RPV water level to reduce PSTG Justification:
The operator is directed to first determine the length of time this evolution may be safely conducted, hence: " determine the Maximum Acceptable Core Uncovery Time". RPV water level is permited to decrease without operator intervention by terminating all injection into the RPV. Vermont Yankee takes this more conservative approach to level reduction, in contrast to the EPGs " reduce RPV water level". The MACUT limit prevents threatening adequate core cooling. l l JDDA - 113 l I
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JUSTIFICA Justification for Deletion, Deviation, or Addition . to the BWROG Emergency Procedure Guideline, Rev.3 (DEV. DEL, ADD) EPG Guldeline/ Contingency: CONTINGENCY #6-RPV FLOODING EPG Section: C6 EPG Step: C6 5.3 l EPG Statement: n/a EPG Basts: n/a I i PSTG Guideline / Contingency: CONTINGENCY #6 RPVFLOODING ; PSTG Section: C6 lPSTG Step: C6 5.2 PSTG Statement: Reference to Caution #31 " Control Room indication of the following parameters are subject to instrument error:
+ Drywell tempererature +/- 10 'F
+ Reactor pressure +/- 40 psi" PSTG Justification:
This caution was added since the operator is directed to perform an action based upon RPV pressure. Therefore, it was deemed necessary that the magnitude of instrument inaccuracy for post accident conditions be included within the procedure. (reference: Memo, M.E. Palionis to D.E. LaBarge, " Addition of Caution to Emergency Operating Procedures, dated 6/20/86) JDDA - 1 ? 4 l l l _____________.___________________%__..____. R_ ..
l I JUSTIFICATION Justification for Deletion, Deviation, or Addition to the BWROG Emergoney Procedure Guideline, Rev.3 (DEv. DEL. ADO) EPG Guideline / Contingency: CONTINGENCY #7 EPG Section: C7 PSTG Guideline / Contingency: n/a PSTG Section: n/a l PSTG Justification:
REFERENCES:
- 1. BWR Owners Group Emergency Procedure Guidelines, Rev. 3.
- 2. Peterson. C.E., et al., " Reducing BN1 Power by Water Level Control During an ATWS, a Transient Analysis," NSAC-70, prepared by Energy Incorporated, for Nuc1 ear Safety Analysis Center, August 1984.
- 3. Chandola, V. and Robichaud, ' Evaluation of BWROG Level / Power Control Strategy for Vermont Yankee Using the BWR-LTAS Code" YAEC-1599, April 1987.
- 4. Memo, J.T. Herron to R.J. Wanczyk, " Contingency 7/EPG's Rev. 4,* VYB 87/927, December 17,1987.
- 5. BWR Owners Group Emergency Procedure Guidelines, Rev. 4.
DISCUSSION The purpose of Contingency #7 is to control RPV water Level under conditions when boron injection is required and the reactor cannot be shut down before suppression pool temperature reaches the boron injection initiation temperature of 110 *F. The operator is directed to reduce RPV water level, thereby reducing core flow and reactor power. This reduces suppression pool heatup by reducing the reactor steaming rate to the suppression pool. This is done to prevent:
. Loss of ECCS Pump NPSH and inability to maintain adequate core cooling.
. Containment failure from overpressurization.
. Petertial unstable steam condensation within the suppression pool.
After the hot shutdown weight of boron has been injected, Contingency #7 directs the operator to restore normal water level, thereby increasing core flow and promoting t. On mixing. The most severe accident which would require implementation of Contingency #7 is an Anticipated Transient Without Scram (ATWS) - specifically, closure of all MSIVs with complete failure of the scram function. The NRC in its Safety Evaluation Report of Contingency #7 of the Boiling Water Reactor Owner's Group EPGs (Safety Evaluation of " Emergency Procedure Guidelines, Revision 2,* NEDO-24934), dated February 8,1983, concluded that the procedure outlined in Contingency #7 is acceptable for the current designs of BWRs. In its evaluation, the NRC identified some potential problems, such as low boron mixing with lowered water level and the possibility cf power and water level oscillations, whose effect on fuel rods is unknown. Significantly, the NRC also pointed out that dropping water level to the top of the active fuel is contrary to normal operator response. In spite of these concerns, the NRC concluded that Contingency #7 would be an appropriate operator action in the event of a failure to scram. JDDA - 115 _ _ _ . . _ _ _ _ > [
JUSTIFICA N Justification for Deletion, Deviation, or Addition to the BWROG Emergency Procedure Guideline, Rev.3 (DEV. DEL. ADO) EPG Guldeline/ Contingency: COfRINGENCY #7 EPG Section: C7 (continued) PSTG Guideline / Contingency: n/a PSTG Section: n/a PSTG Justification: The tradeoff between lower reactor power and reduced core cooling, power oscillatbns and reduced boron mixing is a function of the ATWS scenario consideration. For a worst case ATWS, like that analyzed in Reference 1, no control rods are inserted and the reactor power before the RPV water level is lowered is about 45% of rated. For this case, RPV water level control may be the only way to limit the steam dumped to the suppression pool until sufficient boron has been injected to shut the reactor down. However. for the more probable situations where some negative reactivity has been inserted by control rods, reactor power may be significantly below the worst case 45% but greater than the 2% entry condition for Contingency #7. For these cases. the amount of reactor power reduction possible by reducing RPV water level would be less than for the worse case ATWS. It is conceivable that for many situations, it would be more advantageous to maintain core cooling, avoid possible reactor power oscillations and promote boron mixing by not substantially reducing RPV water level. In the event that the SLCS is not initiated within the first 4 minutes following an ATWS, the analysis described in Reference 2 shows that lowering water level is an effective means to reduce core power. However, water level reduction to the top of active fuel does not reduce core power to decay heat levels. Eventual core power reduction to decay heat levels is necessary to allow the Pressure Suppression Pool Cooling System to maintain PSP temperatures to below acceptable limits. Boron Injection is therefore required to reduce power to deca, heat levels. The water level reduction delays the need to inject boron. Guidance is provided on the timing of boron injection based on the PSP temperature response from the various cases considered. The study also shows that reducing the water level also reduces mixing efficiency of the injected boron and, hence, its effectiveness in reducing core power. Therefore, to enhance boron mixing through increased core flow, the normal water level should be restored after sufficient boron for hot shutdown has been injected. This action is consistent with guidance provided in the EPGs. The results of the analysis described in Reference 2 indicate that the optimum water level following an ATWS and prior to SLCS actuation is about 434" above the bottom of reactor vessel (i.e., 83* above TAF). This level will accomplish most of the achievable power reduction, and it assures good boron mixing to reduce power upon SLCS actuation and provides better level indication to assure core cooling. It should be noted that this optimum water level was calculated using a computer code which could not model core behavior when water level was lowered below the top of active fuel. In the event that water level reduction below TAF is required, guidance provided by BWROG EPG Power / Level Contingency should be followed. This guidance is based upon an analysis which was specifically designed to model core behavior with water level below TAF. It is expected that severe power and water level oscillations will occur. JDDA 116 _ . e
msmc Justification for Deletion, Deviation, or Addition . DEL to the BWROG Emergency Procedure Guideline, Rev.3 (DEV. DEL. ADD) EPG Guideline / Contingency: CONTINGENCY #7 EPG Section: C7 (continued) l l PSTG Guideline / Contingency: n/a I PSTG Section: n/a PSTG Justification: COMPARISON OF GUIDELINES VY Specific Power / Level Control Guideline
. Recommends initiation of SLC within 4 minutes of event.
Ensures sufficient natural circulation within the RPV to provide adequate mixing of borated water.
. Maintains RPV water level within the range of reliable water level indication / instrumentation.
. Preunts torus water temperature from exceeding 200 *F.
The computer code BWR-LTAS (Boiling Water Reactor - Long-Term Accident Simulation) was developed at ORNL and modified for use at Vermont Yankee. It is designed to simulate accidents up to core uncovery. There is no provision to calculate fuel heatup during periods of core uncovery. BWROG Power / Level Control Guideline.- BWROG EPG - Revision 4
. Maintains adequate core cooling (i.e.. PCT 5 1500 'F) via a combination of submergence / steam cooling.
Thus, RPV water level is maintained as low as possible to minimize core power. The analysis used to support this guideline employed bundle heat balance calculations with a composite axial power distribution derived from worst times in core life for a variety of peak LHGRs and fuel types. This methodology is much more accurate than that used in support of earlier revisions of the EPGs. Additionally, guidance has been incorporated which resulted from extensive simulator experience with previous revisions of these guidelines. JUSTIFICATION Because NRC approval of EPG Rev. 4 was delayed to mid September 1988, and addresses the issues contained in Contingency #7, the most prudent, efficient and effective course of action would be to defer action on the implementation of Contingency #7. Our experience indicates that it takes I approximately eight (8) months to incorporate a change of this magnitude into our procedures and to effective!y retrain the operators. Our own experience indicates that operator training and acceptance of the EOPs is critical to their success. JDDA - 117 ____ - _ _ _ _ _ _ _ _ _ __ _ __ A 9 )
JUSTIFICA N Justification for Deletion, Deviation, or Addition
~ to the BWROG Emergency Procedure Guideline, Rev.3 (DEV, DEL, ADD)
EPG Guldeline/ Contingency: CONTINGENCY #7 EPG Secticn: C7 (continued) l PSTG Guldeline/ Contingency: n/a PSTG Section: n/a l PSTG Justification: IMPLEMENTATION The guidance supplied in the Power Level Control Contingency will be incorporated in a revision of the Operational Emergency Procedures in accordance with Vermont Yankee's Procedure Generation Package. Due to the improvements made to the BWROG Power / Level Control Contingency, as reflected in Revision 4 of the EPGs and the added operational versatility it provides when used in conjunction with VY's specific Power / Level control guidance, a delay in implementation is justified until such time as Revision 4 as a whole is implemented at Vermont Yankee. 1 l l JDDA - 118 L___-____-___-_-___________________ x o
l l JUSTIFICA N Justification for Deletion, Deviation, or Addition to the BWROG Emergency Procedure Guideline, Rev.3 (DEV. DEL. ADO) EPG 0"Ideline/ Contingency: OPERATOR PRECAUTIONS EPG Section: GENEFML EPG Step: CAUTION #1 EPG Statement: Monitor the general state of the plant. If an entry condition for a [ procedure developed from the Emergency Procedure Guidelines) occurs, enter that procedure. When it is determined that an emergency no longer exists, enter [ normal operating procedure). EPG Basis: Operator awareness of overall state of the plant during emergency conditions is an extremely important requirement for successful execution of any set of emergency operating procedures. Symptoms rather than events are the Entry Conditions to the EPGs. Occurance of any Entry Condition requires entry into the plant emergency operating procedure developed from the guideline. PSTG Guldeline/ Contingency: OPERATOR PRECAIJTIONS PSTG Section: GENERAL PSTG Step:) CAUTION #1 PSTG Statement: Monitor the general state of the plant. If an entry condition for other OE occurs, enter that procedure. PSTG Justification: From training, the operator knows that if the entry condition which determined that an emergency condition occured no longer exists, he is to enter normal operating procedures. In fact, AP 0109, Plant Recovery Procedure, was developed with this in mind. JDDA - 119 _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ . _ _ _ _ _ _ _ _ _ _ _ _ _ m
l 1 Justification for Deletion, Deviation, or Addition ms m " l E: DEL to the BWROG Emergency Procedure Guideline, Rev.3 (DEV. DEL A00) EPG Guldeline/ Contingency: OPERATOR PRECAUllONS EPG Section: GENERAL EPG Step: CAUTION #2 E.PG Statement: Monitor RPV water level and pressure and primary containment temperature and pressure from multiple indications. EPG Basis: Because of the significance the values of these parameters have with respect to execution of the EPGs, the operator is instructed to use multiple indications sufficient to assure the validity of the information. PSTG Guidellne/ Contingency: OPERATOR PRECALTTK)NS PSTG Section: GENERAL PSTG Step: n/a PSTG Statement: n/a PSTG Justifleation: Operator training encompasses the necessity of utilizing multiple indications, when available, when determining if any particular action is required. JDDA - 120
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JUSTIFICA N Justification for Deletion, Deviation, or Addition to the BWROG Emergency Procedure Guideline, Rev.3 (DEV, DEL. ADO) l EPG Guidellne/ Contingency: OPERATORPRECAUTIONS EPG Section: GENERAL EPG Step: CAUTION #3 EPG Statement: If a safety function initiates automatically, assume a true initiating event has occured unless otherwise confirmed by at least two independent indications. EPG Basis: Since the initiation logic for auto initiation of safety systems includes confirmatory signals, each automatic safety function is to be considered correctly and appropriately initiated until it can be otherwise confirmed by two independent indications. PSTG Guideline / Contingency: OPERATOR PRECAUTIONS PSTG Section: GENERAL PSTG Step: n/a PSTG Statument: n/a PSTG Justlfleation: Operator training encompasses the requirement that at least two independent indications are needed prior to determining that a safety system auto initiation may be inhibited. JDDA - 121 _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _n a
_ - _ _ _ _ - _ _ _ _ _ _ _ _ _ _ _. ______ ____ __ _____=______________ _ _ -__ _ _ - _ _ _ _ _ _ _ _ _ -__ Justification for Deletion, Deviation, or Addition JUSTIFICA N to the BWROG Emergency Procedure Guideline, Rev.3 (DEV. DEL, ADO) EPG Guldeline/ Contingency: OPERATOR PRECAUTIONS EPG Section: TERAL EPG Step: CAUTION #4 l EPG Statement: Whenever RHR is in the LPCI mode, inject through the heat exchangers as soon as possible. l EPG Basls: Establishing LPCI flow through the RHR heat exchangers as expeditiously as possible provides for prompt removal of decay heat from the primary containment. PSTG Guideline / Contingency: OPERATOR PRECAUTIONS PSTG Section: GENERAL lPSTG Step: n/a PSTG Statement: n/a PSTG Justification: Rather than use an operator precaution, VY's RHR operating procedure directs the operator to direct injection from the RHR pumps through the RHR heat exchangers. Operator training encompasses the requirement that at least two independent indications are needed prior to determining that a safety system auto initiation may be inhibited. JDDA - 122
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JUSTIFICA Justification for Deletion, Deviation, or Addition to the BWROG Emergency Procedure Guideline, Rev.3 (DEV, DEL. ADD) EPG GuldelinelContingency: OPERATOR PRECAUTIONS EPG Section: GENERAL EPG Step: CAUTION #5 EPG Statement: Suppression pool temperature is determined by [ procedure for determining bulk suppression pool water temperature]. Drywell temperature is determined by (procedure for determining drywell atmosphere average temperature]. Containment temperature is determined by (procedure for determining Mark lli containment atmosphere average temperature]. EPG Basis: The suppression pool, drywell, and containment are large volumes where wide variations in temperature may occur, resulting in local temperatures which may not be truly representative of the entire volume. Actions within the EPGs are based upon bulk or average temperatures, not local temperatures, unless specifically stated. Since the methods by which these temperatures are obtained vary from plant to plant, reference to plant-specific procedures is required. PSTG Guldeline/ Contingency. OPERATOR PRECAUTIONS PSTG Section: GENERAL PSTG Step: n/a PSTG Statement: n/a PSTG Justifleation: Vermont Yankee has no specific written procedures for determining bulk or average temperatures. Rather, we have provided direct indication for both drywell atmosphere temperature and suppression pool water temperature. Further, Tech Spec Interpretation #27 provides guidance for determining an average value for suppression pool water temperature, and placement of the drywell temperature sensors was based on the requirement to indicate the bulk air temperature. Operator training ensures a bulk or average value for these parameters are utilized. JDDA - 123
- a
MC Justification for Deletion, Deviation, or Addition E1DEV to the BWROG Emergency Procedure Guideline, Rev.3 (DEV. DEL. ADD) EPG GuldelinelContingency: OPERATOR PRECAUTK)NS EPG Section: GENERAL EPG Step: CAUTION #6 EPG Statement: Whenever [ temperature near the instrument reference leg verical runs] exceeds the temperature in the table and the instrument reads below the indicated level in the table, the actual RPV water level may be anywhere below the elevation of the lower instrument tap. [ TABLE ] EPG Basis: Most BWR RPV water level instruments sense liquid level in the vessel downcomer region by measuring dP between a variable water columri and a reference leg. The dP cells are calibrated to give the correct indicated RPV water level when RPV pressure, drywell or containment temperatures and reactor building temperatures are near the values which existed when the instrument was calibrated. If plant conditions vary substantially from these values, errors in the indicated value are introduced. In some cases, changes in the value or trend of RPV water level might not be detected since the dP cell would sense no variation (i.e., level below lower instrument tap while indicated value is on scale and stable). PSTG Guldellne/ Contingency: OPERATOR PRECAtKIONS PSTG Section: GENERAL PSTG Step: CAUTION #6 PSTG Statement: Drywell temperature affects level indication. PSTG Justifleation: Analysis of Vermont Yankee's RPV level indication systems has revealed that when actual level is at or below the lower instrument tap for the given system, the indicated water level in the control room will be " bottomed out". This was analyzed for combinations of RPV pressure and drywell temperature which would result in maximum deviation from calibration conditions. Therefore, it was only necessary to caution the operators that level indication may not be correct; however, the level instruments can still be used for trend indication provided they are still on scale. Additionally, there is sufficient redundency of RPV level indication for the operator to conclude that level cannot be determined, which is an entry condition into Contingency #1 - Level Restoration. JDDA 124 _ _ _ _ _ _ _ _ _ - _ _ _ _ _ _ _ _ . _ _ _ _ _ _ _ _ _ _ _ _ _ _ . R
Justification for Deletion, Deviation, or Addition msmC " E. DEL to the BWROG Emergency Procedure Guideline, Rev.3 (DEV. DEL ADD) EPG Guideline / Contingency: OPERATOR PRECAUTIONS EPG Section: GENERN. EPG Step: CAUTION #7 l EPG Statement: (Heated reference leg instrument) indicated levels are not reliable during rapid RPV depressurization below 500 psig. For these conditions, utilize [ cold reference leg instruments) to monitor RPV water level. EPG Basis: Depressurization of the RPV to below the saturation pressure for the temperature of the water in the RPV water level instrument reference leg causes boiling in the reference leg. Because the heated reference leg temperatures seldom exceed 450 'F (saturation temperature for 500 psig), flashing and possible loss of liquid from the inst;ument reference leg occurs during rapid depressurization below 500 psig. PSTG Guldeline/ Contingency: OPERATOR PRECAUTIONS PSTG Section: GENERAL lPSTG Step: n/a PSTG Statement n/a PSTG Justification: None of Vermont Yankee's RPV level systems have heated reference legs, therefor this precaution does not apply, 1 JDDA 125 I
Justification for Deletion, Deviation, or Addition msmc E DEV to the BWROG Emergency Procedure Guideline, Rev.3 (CEV. DEL ADD) EPG Guideline / Contingency: OPERATOR PRECAUTK)NS EPG Section: GENER4. l EPG Step: CAUTION #8 EPG Statement: Observe NPSH requirements for pumps taking suction from the suppression pool. [ GRAPHS -- RHR and CS flow vs. suppression pool temperature vs. suppression chamber pressure ] EPG Basis: Net positive suction head is a function of the subcooling at the pump suction. This in turn is a function of fluid velocity through the pump, the temperature of the fluid being pumped, the head of water at the pump suction, and the pressure over the head of water. PSTG Guidellne/ Contingency: OPERATOR PRECAUTIONS PSTG Section: GENERAL PSTG Step: CAUTION #8 PSTG Statement: Oberve NPSH requirements for pumps taking suction from the torus. [ GRAPH -- Torus water temperature vs. torus airspace pressure ) PSTG Justifleation: Since the curves are nearly flat over the range of systems *flowrate, the curves provided little information to the operators. It was determined that a greater benefit to an operator would be the ability to anticipate when a system's required NPSH could not be satisfied for a given water i temperature and airspace pressure. This was calculated for each of the ECCS systems taking suction from the torus (i.e., suppression poci) assuming rated flow and a minimum water level. The most ; restrictive system curve was used, resulting in a conservative colution. i 1 JDDA - 126
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JUSTIFICA N Justification for Deletion, Deviation, or Addition to the BWROG Emergency Procedure Guideline, Rev.3 (DEV. DEL. ADD) EPG Guideline / Contingency: OPERATOR PRECAUTIONS EPG Section: GENERAL EPG Step: CAUTION #9 EPG Statement: If signals of high suppression pool water level [12 ft. 7 in. (high level suction interlock); or low condensate storage tank water level [0 in. (Iow level suction interlock)) occur, confirm automatic transfer of or manually transfer HPCI, RCIC, and HPCS suction from the condensate storage tank to the suppression pool. EPG Basis: HPCI, HPCS, and RCIC are each capable of taking suction on either the condensate storage tank (CST) or the suppression pool. If suppression pool water level is high and any of these systems continues to inject into the RPV from the CST, the water level will continue to rise and approach the suppression pool water level limits. Similarly, if CST water level is low and any of these systems continues to draw water from the CST, its source will soon expire. Thus for either of these conditions, it is appropriate to transfer suction to the suppression pool. PSTG Guideline / Contingency: OPERATOR PRECAUTIONS PSTG Section: GENERAL PSTG Step: CAUTION #9 PSTG Statement: If signals of low CST level occur, consider / verify transfer of HPCI and/or RCIC suctions from the CST to the suppression pool. PSTG Justification: Vermont Yankee does not have a HPCS system, nor do we have automatic transfer of suction from the CST to the suppression pool on high suppression pool water level. This is due to analysis results which concluded that the high suppression pool water level would most probably accompanied by suppression pool water temperature > 140 *F, which would render both HPCI and RCIC inoperative due to insufficient cooling of their lube oil. Therefore, the operator is cautioned to consider / verify transfer of suction from the CST to the suppression pool in case there exists a high suppression pool temperature condition. JDDA - 127
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JUSMC N Justification for Deletion, Deviation, or Addition
- e. D E V to the BWROG Emergency Procedure Guidelino, Rev.3 (DEV. DEL, ADD)
EPG Guideline / Contingency: OPERATOR PRECAUTIONS EPG Section: SPECIFIC EPG Step: CAUTION #10 l EPG Statement: Do not secure or place an ECCS in MANUAL mode unless, by at least two independent indications, (1) misoperation in AUTOMATIC mode is confirmed, or (2) adequate core cooling is assured. if an ECCS is placed in MANUAL mode, :.11 not initiate automatically. Make frequent checks of the initiating or controlling parameter. When manual operation is no longer required, resore the system to AUTOMATIC / STANDBY mode if possible. EPG Basis: Caution #10 expands upon Caution #3 by providing specific guidance for manually overriding and resetting ECCS. PSTG Guldeline/ Contingency: OPERATOR PRECAUTIONS PSTG Section: SPECIFIC PSTG Step: CAUTION #10 PSTG St a ts, ment: Do not secure or place an ECCS in manual mode unless, by at least two independent indications, misoperation in AUTOMATIC mode is confirmed, or adequate core cooling is assured. PSTG Justification: Operator training and experience ensures awareness of the fact that an ECCS system which is secured or placed in PULL-TO-LOCK will not initiate automatically. The need to check the contolling or initiating parameters at a more frequent interval is similarly ensured via operator training. Restoration of plant systems is accomplished via OP0109. JDDA - 128 D _ _ _.__._.._________ _ _
JUSTIFICA N Justification for Deletion, Deviation, or Addition to the BWROG Emergency Procedure Guideline, Rev.3 (DEV. DEL ADD) EPG Guideline / Contingency: OPERATOR PRECAUTIONS EPG Section: SPECIFIC EPG Step: CAUTION #11 EPG Statemec1; if a high drywell pressure or ECCS initiation signal [2.0 psig (drywell pressure which initiates ECCS)] occurs or exists while depressurizing, prevent injection from those LPCS and LPCI pumps not required to assure adequate core cooling prior to reaching their maximum injection pressures. When the high drywell pressure ECCS initiation signal clears, restore LPCS and LPCI to AUTOMATIC / STANDBY mode. EPG Basis: Caution #11 expands upon the guidance previously provided in Caution #10 by addressing a specific situation in which it is appropriate to take manual control of low pressure ECCS operation. 7STG Guidellne/ Contingency: OPERATOR PRECAlJTK)NS PSTG S;,ction;l CPECIFIC PSTG Step: CAUTION #11 PSTG Statement: If a high drywell pressure ECCS initiation signal occurs or exists while depressurizing, prevent i injection from those Core Spray and LPCI pumps not required to assure adequate core cooling. i l l PSTG Justification: Operating training ensu.es that the initiation signals for ECCS are known. This is also true for valve , interlocks relating to system inja.; tion, and the need to inhibit injection prior to reaching the injection l pressure. Restoration of plant systems is accomplished via OP0109. ) JDDA - 129 l _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ - - 3 i
Justification for Deletion, Deviation, or Addition WS E CA " E: DEV to the BWROG Emergency Procedure Guideline, Rev.3 (DEV. DEL. A00) EPG Guldeline/ Contingency: OPERATOR PRECAUTIONS EPG Section: SPECIFIC EPG Step: CAUTION #15 l EPG Statement: Open SRVs in the following sequence if possible: (SRV opening sequence]. EPG Basis: When manual SRV actuation is required for RPV pressure control, an opening sequence is preferred which distributes heat uniformly throughout the suppression pool to avoid locally high pool temperatures which may result in inefficient pool cooling or, potentially, unstable steam condensation. PSTG Guideline / Contingency: OPERATOR PRECAUTIONS PSTG Section: SPECIFIC PSTG Step:l CAUTION #15 PSTG Statement: Open SRVs in sequence to distribute torus heat loading. PSTG Justifleation: Vermont Yankee has only four SRVs, designed to discharge in seperate, nearly equal spacing around the suppression pool. Simulator training and the ADS system operating procedure, together with the above guidance and design of SRV discharge system, ensures distribution of heat throughout the pool. JDDA - 130
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msmC N Justification for Deletion, Deviation, or Addition DEV to the BWROG Emergency Procedure Guideline, Rev.3 (DEV. DEL, ADD) EPG Guideline / Contingency: OPERATOR PRECAUTIONS EPG - Section: SPECIFIC EPG Step: CAUTION #16 l EPG Statement: I Bypassing low RPV water level [ ventilation system and) MSIV isolation interlocks may be required to accomplish this step. EPG Basis: Bypassing the low RPV water level portion of the MSIV isolation interlock is appropriate in order to open the MSIVs and re-establish the main condenser as a heat sink. For those plants which also isolate steam l tunnel cooling on low RPV water level, this bypass is required to recre and maintain steam tunnel l temperature below the isolation setpoint for high area temperature. PSTG Guideline / Contingency: OPERATOR PRECAUTIONS PSTG Section: SPECIFIC PSTG Step: CAUTION #16 PSTG S;etement: Bypassing interlocks may be required to accomplish this step. PSTG Justifleation: Specific guidance is provided in the form of appendices to the emergency operating procedures which ensures that only the applicable isolation interlocks are bypassed. JDDA - 131
Justification for Deletion, Deviation, or Addition mmc N e: DEL to the BWROG Emergency Procedure Guideline, Rev.3 (DEV. DEL. ADD) i EPG Guidellne/ Contingency: OPERATOR PRECAUTIONS EPG Section: SPECIFIC EPG Step: CAUTION #17 l EPG Statement: Cooldown rates above [100 *F/hr (RPV cooldown rate LCO)] may be required to conserve RPV water inventory, protect primary containment integrity, or limit radioactive release to the environment. l EPG Basis: The three general circumstances identified in Caution #17 where cooldown rates in excess of the LCO may be required are defined in detail in other locations within the guidelines. PSTG Guideline / Contingency: OPERATOR PRECAUTIONS PSTG Section: SPECIFIC PSTG Step: CAUTION #17 PSTG Statement: n/a ( PSTG Justification: The reason for exceeding the LCO on cooldown rate is easily inferred from the step to which to the caution is applied, thus there is no reason to state the general circumstances. JDDA - 132 _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ . _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _s. I
JUSTIFICA N Justification for Deletion, Deviation, on Addition to the BWROG Emergency Procedure Guideline, Rev.3 (DEV. DEL ADD) EPG Guideline / Contingency: OPERATOR PRECAUYlONS EPG Section: SPECIFIC EPG Step: CAUTION #19 l EPG Statement: Confirm automatic trip or manually trip SLC pumps at {0% (Iow level trip)] in the SLC tank. l l EPG Basis: Failure to secure the SLC pump before its suction is completely exhsusted may result in severe mechanical damage to the pump. PST'G Guldeline/ Contingency: OPERATOR PRECAUTIONS PSTG Section: SPECIFIC PSTG Step: CAUTION #19 PSTG Statement: Manually trip SLC pumps at 0% tank level to insure future availability. PSTG Justifleation: Vermont Yankee does not have an automatic trip of the SLC pumps on low tank level. However, to ensure future availability, the pumps are tripped manually when tank level indicates 0. JDDA - 133 i E________._______.______ _ _ _ _ _ m
Justification for Deletion, Deviation, or Addition JUSTIFICA N to the BWROG Emergency Procedure Guideline, Rev.3 (DEV. DEL. A00) EPG Guideline / Contingency: OPERATOR PRECAUTIONS EPG Section: SPECIFIC l EPG Step: CAUTION #20 EPG Statement: Defeating RSCS interlocks may be required to accomplish this step. EPG Basis: RSCS interlocks are designed to preclude control rod patterns which have not been analyzed or which cause fuel thermal limits to be exceeded. If one or more control rods do not fully insert subsequent to a scramm initiation, the resulting control rod pattern will most likely differ from the programmed sequence, and the RSCS logic will consequently block manual insertion of the withdrawn rods. PSTG Guideline / Contingency: OPERATOR PRECAUTIONS PSTG Section: SPECIFIC PSTG Step: n/a PSTG Statement: n/a PSTG Justification: Bypassing the RSCS interlocks has been incorporated as required into the guideline in the case of Vermont Yankee, this requires bypassing the Rod Worth Minimizer (RWM). JDDA - 134
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JUSTIFICA N Justification for Deletion, Deviation, or Addition to the BWROG Emergency Procedure Guideline, Rev.3 (DEV. DEL. ADD) EPG Guideline / Contingency: OPERATOR PRECAUTIONS EPG Section: SPECIFIC EPG Step: CAUTION #21 l EEG Statement: Elevated suppression chamber pressure may trip the RCIC turbine on high exhaust pressure. i EPG Basis: The RCIC high exhaust pressure trip, typically set at 25 psig, protects the RCIC turbine shaft seals and exhaust piping. PSTG Guideline / Contingency: OPERATOR PRECAUTIONS PSTG Section: SPECIFIC PSTG Step: n/a PSTG Statement: n/a PSTG Justiffeation: Operator training encompasses the conditions which will result in RCIC turbine trip. It is not necessary to include this information. l JDDA - 135
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JUS M CA " Justification for Deletion, Deviation, or Addition E. ADD to the BWROG Emergency Procedure Guideline, Rev.3 (DEV, DEL. ADD) EPG Guideline / Contingency: OPERATOR PRECAUTIONS EPG Section: SPECIFIC EPG Step: n/a l EPG Statement: n/a EPG Basis: n/a PSTG Guideline / Contingency: OPERATOR PRECAUTIONS PSTG Section: SPECIFIC lPSTG Step: CAUTION #26 PSTG Statement: Large reactor power oscillations may be observed while executing this step. PSTG Justification: This is an extention of Caution #25, and was added when it was observed in the course of simulator training that SRV actuation or manipulation during flooding evolutions when all control rods are not fully inserted resulted in large power oscillations. l l JDDA - 136
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WS E CA N Justification for Deletion, Deviation, or Addition . ADD to the BWROG Emergency Procedure Guideline, Rev.3 (DEV, DEL ADO) EPG Guldeline/ Contingency: OPERATOR PRECAUTIONS EPG Section: SPECIFIC EPG Step: n/a EPG Statement: n/a EPG Basis: n/a PSTG Guldeline/ Contingency:l OPERATOR PRECAUTIONS PSTG Section: SPECIFIC PSTG Step: CAUTION #27 PSTG Statement: Do not open MSIVs if a valid high radiation or line break condition has caused the isolation. PSTG Justifleation: This caution was added to work in conjunction with Caution #16, where MSIV low RPV water level isolation is bypassed. If the MSIVs were shut, the initiating isolation conditions (i.e., high steamline flow or high radiation) may no longer exist and would not prevent the operator from re opening the MSIVs. , I t i JDDA - 137 l 1 l { I t
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l l JUSMCA " Justification for Deletion, Deviation, or Addition ADD j E: to the BWROG Emergency Procedure Guideline, Rev.3 (DEV. DEL. ADD) EPG Guideline / Contingency: OPERATOR PRECAUTIONS EPG Section: SPECIFIC EPG Step: n/a l EPG Statement: n/a EPG Basis: n/a PSTG Guideline / Contingency: OPERATOR PRECAUTIONS PSTG Section: SPECIFIC PSTG Step: CAUTION #28 PSTG Statement: Do not vent via SGTS if Drywell pressure is greater than 7 psig. PSTG Justification: Analysis has shown that at this drywell pressure, the downsteam pressure in the SGTS trains (assuming steam flow through the system) could exceed the SGTS pressure rating. (reference: " Analysis of Primary Containment Venting Through Atmospheric Control and Standby Gas Treatment Systems for VYNPC", GP-R-213031, General Physics Corp., July 1984) JDDA - 138 _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _s e
i Justification for Deletion, Deviation, or Addition JUSTIFICA N to the BWROG Emergency Procedure Guideline, Rev.3 (DEV, DEL ADD) EPG Guldeline/ Contingency: OPERATOR PRECAUTIONS EPG Section: SPECIFIC EPG Step: n/a l EPG Statement; n/a EPG Basis: n/a l PSTG Guideline / Contingency: OPERATOR PRECAUTK)NS PSTG Section: SPECIFIC PSTG Step: CAUTION #30 PSTG Statement: Initiate Torus Cooling if HPCI, RCIC, or SRVs are in use provided RHR subsystem not required for: ! . Core Cooling Drywell/ Torus sprays PSTG Justification: This caution was added as an anticipatory operator action to prevent or limit the heatup rate of the suppression pool. l l l JDDA - 139
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Justification for Deletion, Deviation, or Addition JUSTIFICA N to the BWROG Emergency Procedure Guideline, Rev.3 (DEV, DEL ADD) EPG Guideline / Contingency: OPERATOR PRECAUTIONS EPG Section: SPECIFIC l EPG Step: n/a EPG Statement: n/a EPG Basis: n/a (' PSTG Guidellne/ Contingency: OPERATOR PRECAUTIONS PSTG Section: SPECIFIC PSTG Step: CAUTION #31 j PSTG Statement! ! Control Room indication of the following parameters are subject to instrument error:
- Drywell tempererature +/ 10 'F
- Reactor pressure +/- 40 psi" PSTG Justification:
This caution was added since RPV pressure or drywell temperature is one of the parameters that the operator is directed to control per the applicable PSTG step. It was deemed necessary that the magnitude of instrument inaccuracy for post-accident conditions be included within the procedure. l (reference: Memo, M.E. Palionis to D.E. LaBarge, " Addition of Caution to Emergency Operating Procedures, dated 6/20/86) JDDA - 140 n e - _ _ _ _}}