IR 05000237/1991029
| ML17174B042 | |
| Person / Time | |
|---|---|
| Site: | Dresden  |
| Issue date: | 12/10/1991 |
| From: | Leach M, Phillips M, Rescheske P NRC OFFICE OF INSPECTION & ENFORCEMENT (IE REGION III) |
| To: | |
| Shared Package | |
| ML17174B041 | List: |
| References | |
| 50-237-91-29, 50-249-91-31, NUDOCS 9112160242 | |
| Download: ML17174B042 (19) | |
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U.S. NUCLEAR REGULATORY COMMISSION
REGION III
Reports No. 50-237/91029(DRS); No. 50-249/91031(DRS)
Docket Nos. 50-237; 50-249 Licenses No. DPR-19; No. DPR-25 Licensee:
Commonwealth Edison Company Opus West III 1400 Opus Pla.ce Dow~ers Grove, IL 60515 Facility Name:
Dresden Nuclear Power.Station - Units 2 and 3 Inspection At:
Morris, IL 60450 Inspection Conducted:
October 21 through November 12, 1991 Inspectors: ~f eQe:()[I N:.aiv peg~.
Rescheske, RIII
Approved By:.
Lead Inspector Mike R. Mcwilliams, Consultant
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/CU'cJ~i~
_Monte P. Phi&lips, Chief Operational Programs Section Inspection Summary (SAIC)
Inspection on October 21 through November 12, 1991 (Reports No. 50-237/91029CDRS); No. 50-249/91031(DRS))
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Date Areas Inspected:
Routine, safety inspection focusing on the Dresden Emergency Operating* Procedures (DEOPs); implementation of Revision 4 to the BWR Owners Group Emergency Procedure Guidelines (BWROG ~PGs) and the transition to flowchart format EOPs (completed in 1989); the.programs for controlling and maintaining the DEOPs; and actions to resolve previous weaknesses in the EOP program and implementation of the Revision 3 BWROG EPGs, which were identified in the*NRC EOP Team Inspection Reports No.. 237 /88012; No. 249/8801 The inspection was conducted under NRC Inspection Procedure 4200 Results:
No violations of NRC requirements were identified,
. three previously identified open items were closed, and three open items were identifie ~ 911210.
PDR ADOCK 050002J7 Q
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PDR~
The DEOP program and implementation.generally was.adequate, satisfied regulatory requirements, and was consistent with the guidance and recommendations in NUREGs 0899, 1358, and other NRC accepted document In general, the DEOPs were technically
- correct and could be accomplished using exj,sting equipment, controls, and instrumentatio The Writer's Guide for the DEOP flowcharts was considered adequate~ and the DEOPs were consistent with this guidance and reflected significant hwrian factors improvements since the NRC EOP Team Inspection in 198 The licensee's programs for verification and validation (V&V) of the DEOP flowcharts and the DEOP text format support procedures were considered.adequate to assure that the quality of the DEOPs would be maintaine Implementation of these programs completed i for the upgrade to the Revi~:don 4 EPGs and transition to
- flowcharts was also acceptabl Quality Assurance (QA)
involvement in the* area of EOPs appeared to be adequat Several minor program weaknesses and procedure deficiencies*were note Three open items were identified which need licensee resoiution:
(1) deficiencies in DEOP 100 and DEOP 300-1, (2)
lack of documentation for PSTG/flowchart differences, and (3)
philosophy of use of the DEOPs (i.e., entry and exit conditions).
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REPORT DETAILS Persons Contacted Commonwealth Edison Company CCECol L. Gerner, Technical Superintendent J. Kotowski, Production Superintendent G. Smith, Assistant Superintendent, Operations K. Peterman, Regulatory Assurance Supervisor R *. Stachniak, Performance Improvement Supervisor J. Gates, Assistant Technical Staff Supervisor B. Zank, Operating Engineer M. Korchynsky, Operating Engineer K. Yates, Onsite Nuclear Safety Administrator-J. Harrington, Nuclear Quality Programs Maintenance-Group Leader
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a. Speroff, DEOP Coordinator T. Cole, Nuclear Engineer D. Lowenstein, Regulatory Assurance Analyst U.S. Nuclear Regulatory Coml'ilission CNRC)
w. Rogers, Senior Resident Inspector, Dresden D. Liao, Intern, Division of Reactor Projects, Region III The above individuals attended the exit meeting held on November 12, 199 other persons were contacted during the inspection including members of the licensee's operations and quality *assurance_
staf-f.
Action on Previousiy Identified Items The following -open items are considered close These items were ori-ginally identified during the NRC EOP Team Inspection conducted in 198 (Closed) Open Item (237/90009-03):
Identify the location of the proper sources of service water in DEOP 500- The procedure was revised to specify that the source of service water was from the TBCCW heat exchanger tube side vent or drains~ This item is close (Closed) Open Item (237/9000~-04):
Proper use of the words "to" or "and" related to the_4kV breakers in DEOP 500- The licensee corrected the wording in the -
procedure to be consistent with labeling in the control roo This item is close (Closed) Open Item (237/90009-05):
Verify that the EOP equipment cabinet surveillance procedure DOS-0010-15 is implemented when the licensee approves. the procedure for us Revision o was issued and implemented on October 18, 199 The inspectors.sampled the cabinets during the EOP walkthroughs and determined that.the necessary items were contained in the cabinet This item is close.
Inspection Overview The inspection focused ori the Dresden Emergency Operating Procedures (DEOPs); implementation of Revision 4 to the BWR Owners Group Emergency Proeedure Guidelines (BWROG EPGs) and the transition to flowchart format EOPs (completed in 1989);
and the programs for controlling and maintaining the DEOP In addition, the inspectors reviewed the licensee's actions to resolve previous weaknesses in their EOP program and implementation of the Revision 3 BWROG EPGs, which were identified in the NRC EOP Team Inspection Reports No. 237/88012; No. ~49/8801 The inspection consisted of a limited technical and human factors review of selected DEOPs, including control room and in-plant walkthroughs; a human factors review of the Writer's Guide for the DEOP flowcharts and its implementation; a review of the Verification and Validation (V&V) programs and implementation; and an assessment of Quality Assurance (QA) 'involvement in the area of EOP A listing of procedures and other documents utilized during the inspection is given in Appendix A of this inspection repor *
The results of the inspection indicated that the DEOP program and implementation generally was adequate, satisfied regulatory requirements, and was consistent with the guidance and recommendations in NUREGs 0899, 1358, and other NRC accepted document Several minor program weaknesses and procedure deficiericies were note A discussion of the areas assessed and the results is in the following paragraphs, with additional details in Appendix B of this inspection report.
. EOP Review and Walkthroughs The desktop review included comparisons of the Dresden Plant Specific Technical Guidelines (PSTG) to Revision 4 of the BWROG EPGs, and review of the documentation used to justify deviations from the EPGs.. The calculational basis for selected plant specific parameters and curves used in the DEOPs was also reviewe Portions of selected DEOPs were reviewed using the EPGs, PSTG, and the Writer's Guide as a
basi Technical adequacy of selected DEOPs was evaluated using plant system and logic drawing Walkthroughs of a sample of DEOPs were conducted by the inspectors, accompanied by licensed or non-licensed operators who would normally perform the procedure Based on the sample of reviews and.waikthroughs, the inspectors concluded that the DEOPs were, in general, technically correct and could be accomplished using existing equipment, controls, *and instrumentatio Several minor procedure deficiencies and program weaknesses were identified, as follows: Technical Issues (1)
DEOP 100 Reactor Control During the walkthrough*of* this procedure, the Senior Reactor Operator (SRO) accompanying the inspectors was provided with the necessary plant data, and asked to determine whether Emergency Core Cooling System (ECCS) Net Positive Suction Head (NPSH) requirements were met using the curves in the DEO The operator incorrectly applied the data to the NPSH curves by considering the combined flow of Core Spray and Low Pressure Coolant Injec~ion (LPCI).
The operator determined that NPSH requirements were met, whereas they were not met for one of the Core Spray pump The requalif ication training supervisor stated that the curves in DEOP 100 were included in a recent requalification training cycl The licensee agreed to investigate the extent of this potential training weakness and identify an appropriate resolutio *
The supporting calculations for the ECCS NPSH cunres were reviewe These calculations assumed one LPCI pump in service, which did not allow for the increased head loss in the common section of piping when two pumps are in servic The licensee was addressing this issue by reviewing the engineering calculations to determine if the increased head loss would affect the accuracy of the curves in the DEO The above issues, regarding DEOP 100, are considered to be an Open Item (237/91029-0la(DRS)), pending resolution by the licensee and further review by the NR (2)
DEOP 300-1 Secondary Containment Control The maximum safe radiatio~ levels for the reactor
building were specified as 150.mR/h These values had been determined by the licensee and were based on an operator obtaining a limiting quarterly dose in an eight hour perio Appendix A of the EPG define~ the Maximum Safe Operating Radiation Level to be the highest
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radiation level at which n~ither (1) equipment necessary for the safe shutdown of the plant will fail nor* ( 2) personnel access necessary for the safe shutdown of the plant will be preclude The generic values provided inthe EPG were 1250 mR/h The maximwil safe operating radiation levels are.used when a primary system is discharging into the reactor buildin The EOPs mandate.a reactor scram before the maximum safe value is reached in any area, and_further, an emergency depressurization is requir*ed when any two areas exceed maximum safe level Appendix B of the EPG stated that the criteria of more than one area identifies a wide spread problem which may pose a direct and immediate threat to plant equipment.and to personnel both on and off site.
. The.inspectors questioned the.licensee as to whether the value of 150 mR/hr meets the intent of Maximum Safe Operating Radiation Level, and if it really poses a direct and immediate threat sufficient to warrant the severe tr&nsients of reactor scram and emergency depressurizatio The*
licensee agreed to investigate this issue.furthe The specified maximum normal temperatures were 150°F, whereas the maximum safe temperatures were 180° The small difference between the two provided limited opportunity for operating personnel to*implement remedial actions for a primary system leak prior to initiating a scram or emergency depressurization. * The licensee agreed *
to investigate this issue furthe The above issues, regarding DEOP 300-1, are considered to be an Open Item (237/91029-0lb(DRS)), pending resolution by the licensee and further review by the NR PSTG/Flowchart Consistency The inspectors noted numerous differences between the PSTG and the DEOP flowcharts which were not documented and were not identified during the licensee'~ V&V of the DEOPs These differences involved changes in sequence,- changes in logic, and relocation of steps to other DEOP For example, in DEOP 400-5 (Failure to
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Scram), steps to initiate Standby Liquid Control and perform Alternate Rod Insertion were identified in the PSTG as being performed concu'rrently. * In the flowchart however, they were* represented as being performed seque.ntiall Other examples included steps that were being performed in a different order than indicated in the PSTG or as part of a different procedure (or
flowpath) than indicated in. the PST For example, applicable portions of the Emergency Depressurization DEOP were incorporated into the RPV Flooding flowchart, DEOP 400- several other examples are given in Appendix B of this inspection repor Generally these changes in EOP structure appeared to enhance the useability of the flowcharts; however, these differences.were not reflected in the PSTG Deviation Document, and were not clearly discussed in the Roadmap document which described the translation of the PSTG to flowchart Because of the uncontrolled nature of these changes, the potential existed for inadvertently altering the operational strategy intended by the PST Though these deviations from the PSTG and BWROG EPGs did not appear to be technical deviations, several were changes in the sequence of operator actions, and should be documented and justifie From a procedur maintenance and revision standpoint, the differences between the PSTG and.flowcharts should be documented and justifie The licensee agreed to conside* documenting these differences in the Roadma This issue~ along with -the associated examples in Appendix B of this inspection report, is considered to be an Open Item (237/91029-02(DRS)), pending resolution by the licensee and further review by the NRC *
. *Philosophy of Use Appendix B of the BWROG Guidelines (OEI Document 8390-4B) states that EOP entry conditions are specified to provide advance warning of potential severe plant conditions and to assure that timely action will be taken to prevent degradation to an emergenc Consistent with the symptomatic approach in defining entry conditions, occurrence of any entry condition requires entry to the appropriate EO Further, termination of the emergency condition rather than the termination of an event is the general exit condition for the EOP The licensee's philosophy on EOP usage, including the lesson plan which provided training to licensed operators on EOP usage, appeared to be contrary to the symptomatic approach to EOP In general, the philosophy* allowed operator judgement as to when the
EOPs need to be entered and execute The lesson plan stated that it was possible that an entry condition may arise due to a slightly abnormal operating condition, and the EOPs need not be executed, thus giving th operator margi'n to make this judgemen This philosophy, in effect, allowed the operator to diagnose the event, which was contrary to the symptomatic approach to EOP An example of this philosophy, though minor, was the torus heatup event on August 30, through September 1, 199 The EOPs were not entered and executed when the entry condition of 95°F torus temperature was reached, since the SCRE had not deemed it an emergen.c The licensee's lesson plan also stated that the EOPs were exited whenever the exit conditions were satisfied or it had been determined that an emergency no longer existed, allowing operator judgement as to when the EOPs could be exited or if there was a real need to *be
- in the EOP The term "emergency" was not defined, and the criteria for exiting an EOP was also not define Using the symptomatic approach to EOPs, any entry condition reqUires EOP entry and executio Exiting an EOP should reqUire satisfying a predetermined and defined set of criteri The licensee agreed to re-evaluate the Dresden philosophy on EOP usage, and to
- more clearly define expectations for usage to the
- .operations staf This issue is considered to be an Open Item (237/91029-03(DRS)), pending resolution by the licensee and further review by the NR.
EOP Writer's Guide Guidance for the development and revision of the DEOP flowcharts was provided in the Dresden Emergency Operating Procedure Writer's Guid This document was originally prepared for Dresden by Operations Engineering Inc. (OEI)
- and had been modified by the license While generally adeqUate, some weaknesses were note Several of the deficiencies noted by the inspectors had previously been identified by the Braidwood/Corporate(CECo) Human Factors Department over a year ago and had not yet been addresse The licensee indicated that a revision to the Writer's Guide would be forthcoming.at which time relevant comments from the previous human factors review along with those identified by the inspectors would be addresse Areas where weaknesses were found are discussed belo A select sample of the DEOPs were reviewed for consistency with the Writer's Guide and human factors principles as described in NUREG.0899 and NUREG/CR-522 In general, the procedures were consistent with this guidance ~nd reflected ~ignificant
- human factors improvements over the versions reviewed-during the NRC EOP Team Inspection in 198 Specific human factors comments related to the procedures reviewed are provided in Appendix B of this inspection repor The Writer's Guide in many instances served more as ah explanation of the flowchart conventions and symbolism than as a.guide.designed to.help translate the PSTG steps to EOP flowchart Symbols used to display certain concepts were described, but the application of.
the concept was not always made clea For example, the discussion of "Conditional Steps" began by-stating the various options for formatting conditional steps,*
but provided no discussion of what a conditional step was.or when it should be use Another example was the discussion of connecting lines used for branch point The symbqlism -used to display two or more concurrent flowpaths was provided; however, there was no discussion of why or when concurrent flowpaths would be use The Writer's Guide contained several typographical errors and incorrect page references.. While these types of errors should not affect useability of the Writer's Guide, they do indicate a lack of attention and thoroughness with which the document has been reviewe In some cases, it was not clearly. specified which alternate formats should be used. * For example, the Writer's Guide stated that complex decisions comprising two or more conditional clauses shall be presented as chains of simple "yes/no" questions, ea.ch enclosed in separate diamond The Writer's Guide also stated that
"Complex.conditional clauses niay be presenteq using multiple diamonds," and that "a series of consecutive conditional statements may be consolidated into a decision table.". It was not.clear when. the multiple diamond format was to be used as opposed to decision table forma Similarly, clear distinction was not made between when notes were to be used versus
"details" to provide supplemental informatio In a number of instances, the Writer's Guide left decisions to the discretion of the procedure writer by stating requirements to be "generally followed", such as when to use the decision table forma Another example was the discussion of emphasis techniques where it is stated that these techniques may be used at the discretion of the write The requirements for using*
specific techniques should be defined such that writer discretion was not relied o This guidance was not
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sufficient to ensure consistent use of the _Writer's Guid In some cases the Writer's Guide relied on examples to illustrate a requirement instead o_f clearly* specifying what the requirement wa For example, the.Writer's Guide.stated that when intermixing conditional-clauses was unavoidable, "clauses shall be arranged so as to clearly define the logical structure of the instruction." Rather than specifying the prescribe method(s), an example was provide While. examples are helpful, they should be used to clarify requirements, not replace the * *. There were several instances of * examples provided which did not support the discussion in the Writer's Guid For example, the disc-ussion on.use of pointers or the formatting of Cautions was not consistent with an example provided which showed a caution preceded by a pointe Another example was the discussion of references to support procedure The example given ref erred to performing the support procedur,e
"concurrently".
However, the discussion provided indicated that "Execution of the primary flowpath continues when the evolution has been performed."
This indicated that the actions were in fact not to be performed concurrentl Also, the example given for Component Identification does not reflect the guidance given in the disc:ussion regarding printing specific control panel designations in uppercase letter There were also instances where guidance was lacking in the Writer's Guid For example, the discussion of logic terms did not provide guidance on highlighting or positioning of these terms in the procedural step Another example was that the instructions for Notes did not* specify whether Notes were _to be placed before or after the steps -t;.o which they appl.
Verification and Validation CV&V)
The licensee's programs for verificat;i.on and validation of the DEOP flowcharts and.the DEOP text format support procedures were considered adequate to assure that the quality of the DEOPs would be maintaine The inspectors reviewed a sample of V&V documentation completed for the upgrade to the Revision 4 EPGs and transition.to flowcharts, and determined that the implementation of the V&V programs*
was also acceptable, with the following exceptio The inspectors identified a concern with DEOP 300-1 which should have been identified by the licensee's V&V process.
Area temperature alarms for the reactor building ranged in value from. 160°F (two rooms) to 200°F (five rooms).
The latter alarm values were above the maximum safe valu The operator in the control room was made aware of abnormally high temperatures by an area high tempe_rature annunciator.
. This annunciator alerts the operator to investigate the.
problem by observing the chart recorder on a control room back panel, and to enter the DEOPs ori a valid alar For rooms with alarm temperatures above the maximum safe value, the operator was unlikely to implement remedial actions or*
initiate the necessary actions as required by the DEOP For example, the operator would be required to initiate a reactor scram prior to reaching 180°F under the condition where a primary system is discharging into the reactor buildin With an alarm value set at 200°F, the action required prior to 180°F may not be performe On October 30, 1991,_ in response to this concern, the licensee implemented new alarm setpoints for both Unit 2 and 3, which corresponded to the DEOP entry condition (maximum normal values) of 150° The inspectors had no further concerns*
regarding this issu *
The inspectors held.discussions with the licensee regarding enhancements to the V&V programs which could improve the proces The licensee agreed to consider the following items:
(1)
The checklists should be more specific to the type of procedure being evaluated as well as the type of
- valida.tion activity being performe For example, the support procedure (text format DEOP) validat.ion checklist included an item regarding the need for additional guidance during the transien Since the support procedure validation typically involved an in.;..plant activity inde'pendent of control room (or
. simulator) activities, this item was not particularly relevan The support procedure checklist would benefit from inclusion of more items specifically addressing in-plant conditions _that might affect an operator's ability to physically accomplish procedural step Examples of such items include environmental hazards, radiological conditions, lighting (and emergency lighting), communications ability, and equipment accessibility and identification.* Some of these are currently addressed by the verification checklist which was completed via tabletop review, rather than in the validatio (2)
The verification program for _the DEOP flowcharts required a verification of conformity to the PST This was considered a "technical" review, and therefore, was not performed by the licensee's human
- factors specialis The inspectors considered.a human factors review of PSTG/flowchart_* consist_ency to be an important element in the V&V process, since human factors persons are very knowledgeable of both the EOP Writer's Guide and good human fact_ors principle Further, a "non-technical" person would he.more likely to identify differences.between the PSTG and flowcharts, especially changes in sequence and logi (3)
Criteria should be developed for specifying the type and extent of V&V required for different types of changes to_ the DEOP Because of a lack of defined criteria, the licensee's programs require a full V&V effort to be implemented for any revision to a DEOP..
The inspectors noted, however, that for temporary procedure changes (non-intent changes), the licensee did not require any type of V& Since a temporary change to a procedure can remain_ in effect until the procedure is revised (possibly years) and several temporary changes can be in effect at the same time,,
temporary changes to the DEOPs should be required to be verified and validated, as is any other DEOP revisio.
Quality Verification Effectiveness The 1988 NRC EOP Team Inspection identified that the licensee had not conducted QA audits in the area of EOP QA involvement is currently considered adequate~ and the licensee was satisfying the commitments made in response to the previous concern Annual GSEP audits routinely include review of selected elements of the EOP program and implementatio Other periodic audits such as those focusing on training may also address EOP.
Open 'Items Open items are matters which have been discussed with the licensee which will be reviewed further by the inspector and which involve some action on the part of the NRC or licensee
- or bot.Three open items were identified during this inspection and are described in Paragraphs 4.a, 4.b, and.*
Exit Meeting The lead inspector met with licensee representatives.
(denoted. in Paragraph 1) on November 12, 199 The inspector summarized the purpose, scope, and findings of the inspection and the likely informational content of the inspection report.. The licensee acknowledged this information and did not identify any information as proprietary.
- Appendix A
.Procedures and Other Documents Utilized During the Inspection Dresden Emergency Operating Procedures CDEOPsl Flowcharts Call at Revision o. dated December 1991)
DEOP 100 DEOP 200-1 DEOP 200-2 DEOP 300-1 DEOP 330-2 DEOP 400-1 DEOP 400~2 DEOP 400-3 DEOP 400-4 DEOP 400-5 Reactor Control Primary Containment Control Primary Containment Hydrogen Control Secondary Containment Control Radioactivity Release Control RPV Flooding Emergency RPV Depressurization Steam Cooling
.Primary Containment Flooding Failure to Scram Text Format DEOPs (latest revision dated December 1989)
DEOP 500-1 DEOP 500-2 DEOP 500-3 DEOP 500-4 DEOP 500-5 Alternate standby Liquid Control Injection, Revision 3
Bypassing Interlocks arid Isolations, Revision 4.
Alternate Water Injection Systems, Revision 4 Containment Venting, Revision 3 Alternate Insertion of. Control Rods, Revision Supporting DEOP Programs, Procedures, and Other Documentation DAP 09-04, "Control of Dresden Emergency Operating Procedures", Revision 4, June 1991 Dresden Emergency Operating Procedure Writer's Guide Dresden Emerg~ncy Operating Procedure Validation Program for DEOP Flowcharts Flowchart Validation Documentation (dated 1989):
Flowchart Validation Outline, Validation Scenario Checklists, Flowchart Validation Discrepancies/Resolutions Dresden Emergency Operating Procedure Validation Program for DEOP Support Procedures
Support Procedure Validation Documentation (dated 1989):
DEOP 500 Validation Checklists* & Questionnaires, DEOP 500 Validation Discrepancy Records
Appendix A
Dresden Emergency Operating Procedure V~rif ication Program Verification Documentation (dated 1989):
Flowchart Verification Checklists, Flowchart Verification
- Discrepancies/Resolutions, DEOP 500 Verification Checklists, DEOP 500 Verification Discrepancies Dresden Plant Specific Technical Guidelines (PSTG) and PSTG Deviation Document PSTG vs. DEOP "Road Map"*
. Dresden Source Documents - Appendix C Data and Calculations DEOP Development Books DEOP Review Items (dated 1987 -
1991)
Appendix B Detailed Comments on the EOPs DEOP 100 Reactor*control o
The first step of the procedure stated "Has a*scram been initialed" instead of "initiated".
The licensee agreed to correct this erro DEOP 200-1 Primary Containment Control o
Primary Containment Hydrogen and Oxygen flowpath -
The logic term "OR" which appears twice in the contingent action table should be highlighted, in accordance with the Writer's Guid There were also several other instances in other paths of this procedure where logic terms should be highlighte * o Drywell Temperature flowpath - Typo in first step. ("to to").
o Torus Bulk Temperature flowpath -
The second step stated "Operate all available torus cooling."
The term operate was not defined as an approved verb in the Writer's Guid The object of this statement was also not clearly specifie A series of decision diamonds and instructional step rectangles were used to display steps for reactor scram and entry to DEOP 10 The same logic was presented by means of a logic table under the Drywell temperature flowpat Consistent structure should be used for similar step A step directed the operator to "Enter DEOP 100, RPV Control", whereas the title of DEOP 100 was "Reactor Control."
The step to maintain torus bulk temperature below the heat capacity limit was not in the PSTG and no justification was provided in the deviation documentatio o Torus Water Level flowpath - In the second contingent action step, the phrase "Secure HPCI" was use Secure was not an approved verb in the Writer's Guid DEOP 200-2 Primary Containment Hydrogen Control
The override at the beginning of this procedure stated
"Drywell or Torus hydrogen concentration cannot be determined to be below 6% AND Drywell or torus oxygen
Appendix B
concentration can.not be determined to b.e below 5%".
The wording of this step which included multiple con.di tional statements and negatives was confusin This comment was also made by the Performance Assessment Team which reviewed the DEOPs in April 199 The confusing nature of this step was evidenced by the.operator's misinterpretation of the i*ntent during the walkthrough of this procedure.. The licensee concurred with this observation and agreed to consider alternate wordin o The PSTG step PC/Hl called for.operator action if drywell or torus hydrogen concentration reached 0.25%.
The DEOP indicated the action level to be 0.3 %.
Although the licensee's stated rationale for this discrepancy was reasonable (instrument accuracy), there was no written justification provided in the PSTG/DEOP Roadmap document or the. PSTG/EPG * deviation documen Also related to thfs *
concern was an operator comment, that was being carried as an open item by the licensee, stating that the hydrogen monitors read about 0.5% during normal operation, and therefore the 0.3 level.was of little us This comment has been unresolved since January 198 The licensee agreed to take action to close this ite o A decision point directed the operator to determine if the offsite radioactivity release rate was expected to remain below the LCO during containment ventin It was not clear how the operator was supposed to make this determination prior to venting since he was not directed to request the Radiation Department to sample the primary containment until after this decision poin If the operator decided that the release rate will not remain below the LCO, he will exit the main flow path and never call for samplin o The PSTG provided an qverride directing isolation of vent and purge on a release rate exceeding the LC The PSTG placed this override before the step calling for primary containment samplin The DEOP placed the override after this ste There was no justification for this deviatio The licensee agreed to review the sequencing of these step There were a total of four instructional steps directing the operator to vent or vent and purge the primary containment..
The PSTG specified only two points where vent.and purge was to be performed (PC/H-1 and PC/H-2).
The extraneous DEOP steps may have resulted from a misinterpretation of the PSTG substeps which provided details of how to perform the two primary steps. The licensee indicated that the need *for these steps would be reassesse *
Appendix B
o Following t~e first instructional step _to vent, a decision diamond was.presented asking the.operator if the drywell or torus can be vente This logic would be more appropriately displayed as a contingent action.following the original instruction to vent (If venting not.possible~ then continue at. * * ).
DEOP 400-1 *RPV Flooding o
Table 400-1-D (in the ATWS flowpath) included the SBLC test tank and SBLC boron tank in the list of aiternate injection system These systems were inadvertently omitted in the list in the PST The licensee planned to revise the PSTG accordingl o PSTG step C4-4 *(in the non-ATWS flowpath) stated to return to step C4-3.l if RPV water level indication is not
restore The logic in the flowchart returns the operator to step C4-2, which required the operator to perform a decision and an action prior to step C4-This deviation from the PSTG was not documented or justifie According to
.the licensee, this change in sequence was due in part to space limitations on the flowchar The licensee agreed to document the justification for this deviation *
. DEOP 400-5 Failure to Scram o
Reactor Power flowpath - Steps to initiate SBLC and perform alternate rod insertion were identified in the PSTG as being performed concurrently. In the flowchart these steps were represented as being performed sequ~ntiall DEOP 500-1 Alternate Standby Liquid Control Injection o
The word AND, when used as a conjunction, was improperly highlighted as a logic term throughout the procedur o several valve position indicator lights on the Condensate Demineralizer panel were burned ou The licensee agreed to replace the light o Under Step 1-f (5), there was a reference to Resin Inlet Valve This was a single valve, marked Valve "S".
Appendix B
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o Substeps a, b, and c, of Step 4, all used different wording (verbs) to indicate movement of a switcp to a new positi.o The wording should be consistent and in agreement with the direction.in the Writer's Guid *
DEOP 500~3 Alternate Water Injection Systems
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o Step 2a of the procedure referred to a condensate demin bypass valve, whereas the valve was labelled service unit bypass valv o Step 4g stated to use the fire system for make-up water if demineralized water was not availabl This step should appear prior to starting the pumps to provide protectio Step Ga stated to verify the pump was within operating parameters.. The specific parameter(s) of interest should be
. stated, and the limits specifie o The label was missing from the breaker for MO 205-2-o Step 8.d should reference MCC 27-o Step 8.e directed the operator to select and manually open one "E" valv This step should direct the operator to
- select the valve deenergized in step 8.d. *
o Step 10.a should identify the locations of the three fire hose stations necessary to perform this ste DEOP 500-4 Containment Venting o
The procedure should be organized such that there is a clear link between this procedure and the governing procedure DEOP 200- All references to vent, purge, or vent and purge should be precis The EPG states:
(1) vent and purge depending on offsite release rates, and (2) vent and purg irrespective of radiation release rate Within these steps various aJternative methods to vent or purge are given depending on plant Condition The procedure should clea"rly implement these steps as directed by DEOP 200- o Step 3d ref err~d to drywell purge fan inlet and outlet dampers, whereas the fan was labelled as the drywell and torus purge* exhaust fa The inlet dampers and outlet dampers are labelled 2-5772-59 A & B and 60 A & B respectively, whereas the procedure did not provide numerical identificatio The inlet dampers did not have open or closed position label *
- Appendix B
DEOP 500-5 Alternate Insertion of Control Rods o
The rectangular block containing the CRD vent valve 'should be labelled with the CRD numbe This would facilitate prompt action to insert rods in the preferred sequence.