IR 05000461/1990013
| ML20044A032 | |
| Person / Time | |
|---|---|
| Site: | Clinton  |
| Issue date: | 06/14/1990 |
| From: | Lanksbury R NRC OFFICE OF INSPECTION & ENFORCEMENT (IE REGION III) |
| To: | |
| Shared Package | |
| ML20044A022 | List: |
| References | |
| 50-461-90-13-EC, EA-90-100, NUDOCS 9006270321 | |
| Download: ML20044A032 (25) | |
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L U.S; NUCLEAR REGULATORY COMMIS$10N
REGION III
Report No. 50-461/90013(DRP)
EA 90-100 Docket No. 50-461 LicenseNo.NPF-6h l
Licensee:
Illinois Power Company
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500 South 27th Street
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Decatur, IL 62525 Facility Name: Clinton Power Station Meeting At:
NRC Region III Office, Glen Ellyn Illinois Meeting Conducted: May 31, 1990 P
Inspectors:
P. G. Brochman R. D. Lanksbury S. P. Ray i
F. L. Brush J. B. Hicle
Approved By:
6 ' ot 90 m
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p::t^r-ProjectsSection3B L% ksbury, M ef Date
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Inspection Summary Meeting on May 31, 1990 (Report No. 50-461/900013(DRP))
Matters Discussed:
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The circumstances surrounding the events on April 11, 1990, which led to the withdrawal of control rods while the main turbine bypass valves were
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open in apparent violation of Technical Specification 3.1.4.1.
NRC review of the events was previously documented in Inspection Report No.50-461/90009(DRP).
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F DETAILS 1.
Persons contacted
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_ Illinois Power Company J. Perry, Vice President J. Cook,: Manager Clinton Power Station
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c F. Spangenberg, Manager, Licensing and Safety y
R. Wyatt, Manager. Quality Assurance L
P. Yocum, Director.-Plant Operations g.;
R. Gill, Manager, Projects and Assessments
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C. Kreidler, Assistant Shift Supervisor G. Reed, Shift Supervisor
R. Russell, Control Room Operator-
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P. Nauyalis, Shift Technical Advisor L.
R. Phares, Director Licensing
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A. Ruwe, Director, System and Reliability Engineering
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D. Morris, Previous Director, Plant Operations l
P. Martin, Control Room Operator.
F. Perryman, Control Room Operator T.' Arnold.. Licensed Operations Project Engineer R. Stirn, Manager, Systems Integration Engineering,
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GE Nuclear Energy-b.
U.S. Nuclear Regulatory Commission E. Greenman, Director of Reactor Projects, RIII H. Miller,, Director of Reactor Safety. RIII
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R. Lanksbury, Chief, Reactor Projects Section 3B, RIII
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' W. Troskoski, Office of Enforcement G. Wright, Chief, Operations Branch, Division of Reactor Safety RI!!
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P.-Brochman, Clinton. Senior Resident Inspector, RIII
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'J. Grobe,. Director of Enforcement, RIII B. Derson, Regional Counsel, RIII
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T. Burdick, Chief, Operator Licensing Section 2, Division of Reactor Safety. RI!!
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Enforcement Conference n"
As a-result of.the apparent violations of NRC requirements regarding the-April 11, 1990,- event of control rod withdrawal with the main turbine.
bypass valves open, an Enforcement Conference was held in the Region III t0ffice on May-31, 1990. The preliminary findings, which were the basis
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'for the apparent violations, were documented in NRC Inspection.9.eport.
I No 50-461/90009(DRP) dated May 10, 1990.
The conference attendees are identified in Paragraph 1 of this report.
Outlines of the. licensee and s -
b NRC Region III presentations are provided in the attached Enforcement Conference handouts.
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LThe licensee agreed witM the inspection findings contained in Inspection'
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Report.No.;50-461/90009 and generally agreed.that anLapparent violation Lof. Technical: Specification 3.1'4.1 occurred. The licensee posited, however,.
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2-that the operator action to close the bypass valves by. increasing generator '
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- load' set, in lieu of insorting rods'as required, was technically correct;
.The licensee also identified " competition between operating shifts" as a)
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factor in.the self imposed. shift-emphasis on schedule adherence.' Licensee
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, management generally discussed methods to reduce the negative impact of
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operating shift competit'on on plant operations.,
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The evaluation and~ disposition of the issues discussed during the conference will be documented in subsequent:comunications.
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ILLIN0IS POWER COMPANY CLINTON POWER STATION j
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ENFORCEMENT CONFERENCE ON APRIL 11, 1990 CONTROL R0D MANIPULATION EVENT
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MAY 31, 1990
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DISCUSSION i
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SUMMARY OF EVENT AND IP POSITION II.
SIGNIFICANCE AND CAUSES
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III.
CORRECTIVE ACTIONS
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OPERATOR ACTIONS AND RESPONSES V.
OTHER RECENT EVENTS j
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NRC AND INDEPENDENT TEAM RECOMMENDATIONS
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'VII.
CONCLUSION y
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SUMMARY OF EVENT AND IP POSITION I
o OPERATORS WITHDRAWING CONTROL' RODS FROM 25% TO 35%
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POWER AT 0728 HRS o
LOAD SETPOINT, WHICH CONTROLS OPENING OF BYPASS
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VALVES, NOT INCREASED
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o LAST ROD PULLED AT 0747 HRS i
o MAIN TURBINE BYPASS VALVES FOUND OPEN AT 0833 HRS o
BYPASS VALVES CLOSED AT 0836 HRS BY RAISING LOAD SET, AND INVESTIGATION INITIATED o
VIOLATION OF TECH SPEC 3.1.4.1 IDENTIFIED
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o PLANT SUBSEQUENTLY BROUGHT TO COLD SHUTDOWN
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IP GENERALLY AGREES'THAT VIOLATIONS OCCURRED AS
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s II.
SIGNIFICANCE AND CAUSES
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o ACTUAL PHYSICAL SAFETY SIGNIFICANCE WAS MINOR
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EVENT INVOLVED REACTIVITY MANAGEMENT o
HPES EVALUATION AND MANAGEMENT REVIEW IDENTIFIED THE FOLLOWING CAUSES FOR THE EVENT ATTENTION TO PLANT INDICATIONS
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COMMUNICATIONS / INFORMING SUPERVISION 0F
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UNEXPECTED' PLANT RESPONSE
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CONTROL OF EVOLUTIONS DURING
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TURNOVER / PERCEIVED TIME PRESSURE e
PROCEDURAL COMPLIANCE
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III.
CORRECTIVE ACTIONS
o OVERALL ACTIONS f
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SHUTDOWN PLANT
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DIRECTORS ON SHIFT TO MONITOR EVOLUTIONS
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ATTENTION TO PLANT INDICATIONS
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COMMUNICATION
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CONTROL DURING TURNOVER / PERCEIVED TIME
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PRESSURE PROCEDURAL COMPLIANCE
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OTHER CONTRIBUTING FACTORS
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CORRECTIVE ACTION - ATTENTION TO PLANT INDICATIONS
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o SHIFT CREW BRIEFINGS o
RETRAINING (INCLUDING SIMULATOR)/ TESTING i
o-MEETINGS WITH SENIOR MANAGEMENT o
PROCEDURE CHANGES o
REVISIONS TO ONGOING PROGRAMS TO ASSURE THAT OPERATORS ARE CONTINUALLY ENCOURAGED TO VERIFY i
PLANT PERFORMANCE THROUGH AVAILABLE INDICATIONS j
(BY 8/31/90)
SIMULATOR TRAINING
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SHIFT SUPERVISORS REAFFIRM WITH OPERATORS
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AUDIT / SURVEILLANCE PROCEDURES
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CORRECTIVE ACTION - C0144UNICATION I
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o MEETINGS BETWEEN VICE PRESIDENT AND
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o MEETINGS BETWEEN VICE PRESIDENT AND SHIFT-CREWS
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o SENIOR-LEVEL INDIVIDUAL TO MONITOR
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PERFORMANCE
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o RETRAINING
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CORRECTIVE ACTIONS - CONTROL DURING TURNOVER /
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PERCEIVED TIME PRESSURS
o RETRAINING
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o PROCEDURE CHANGES - LIMIT CONTROL ROOM ACTIVITIES DURING REACTIVITY CHANGES
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o PROCEDUR.E CHANGES - PANEL WALKDOWNS DURING TURNQVtRS o
STANDING ORDER ON TURNOVER
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CORRECTIVE ACTION - PROCEDURAL COMPLIANCE
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CORRECTIVE ACTION - OTHER CONTRIBUTING FACTORS
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o PROCEDURES AND TECH SPEC WORDING
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o DESIRE TO COMPLETE EVOLUTIONS o
SIMULATOR TRAINING o
SIMULATOR UPDATE o
ANNUNCIATOR ALARM FOR VALVES o
UNDERSTANDING OF XENON TRANSIENT
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OPERATOR ACTIONS AND RESPONSES l
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o OPERATOR PERFORMANCE CONTROL ROD WITHDRAWAL SEQUENCE CORRECT
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AND RATE CONSERVATIVE CAREFUL NEUTRON FLUX LEVEL MONITORING
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REACTOR POWER ASCENSION RATES REMAINED
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WITHIN TECH SPEC LIMITS AS DID REACTOR PRESSUREANDTEMPERATURE
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NO DERELICTION OF DUTY OR DELIBERATE
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DISREGARD OF REQUIREMENTS STOPPED AND CONSIDERED SIGNIFICANCE OF
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INDICATIONS
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BELIEVED (INCORRECTLY) THAT PLANT
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PERFORMANCE WAS EXPLAINABLE (E.G.
COMPUTER LOCKUP OR XENON TRANSIENT)
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ONCE PLANT CONDITIONS RECOGNIZED,
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OPERATOR ACTION WAS SAFE AND TECHNICALLY
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CORRECT.
INVESTIGATION IMMEDIATELY INITIATED, o
SIGNIFICANCE OF OPERATOR PERFORMANCE AND RESPONSES (10)
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OTHER RECENT EVENTS
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o SOUND RECENT PAST OPERATING PERFORMANCE l
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o CLUSTER 0F RECENT INCIDENTS i
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COMMUNICATIONS
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o VIGOROUS ACTION BEING TAKEN IN THESE AREAS
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NRC AND INDEPENDENT TEAM RECOMMENDATIONS
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BYPASS VALVE ANNUNCIATOR - UNDER CONSIDERATION
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o TECHNICAL SPECIFICATION WORDING - BWROG TECH SPEC COMMITTEE TO REVIEW 3 PROPOSED WORDING CHANGES ON 6/18/90
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o REVIEW OF CRITIQUE ADMINISTRATIVE PROCESS - HPES
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GROUP TO ASSUME MAJORITY OF ADMINISTRATIVE RESPONSIBILITIES TO EXPEDITE REPORT PROCESSING;
APPROPRIATE PROCEDURES TO BE REVISED l
o PUBLISHING FORMAL GUIDANCE FOR PERFORMING BRIEFS ON UPCOMING WORK OR EVENTS - PMSO BEING PREPARED o
REVIEWING THE PLAN AND RESOURCES FOR ACHIEVING PROCEDURAL IMPROVEMENT GOALS - REVIEW COMPLETE;
ADDITIONAL CONTRACTORS BEING UTILIZED AND PERMANENT PERSONNEL HIRED
o IP MANAGEMENT WILL CONTINUE TO REINFORCE l
CONSERVATIVE OPERATING PHILOSOPHY
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l Actions in Response to Independent Team Recommendations Reconeendation Action Rwiew critique administrative The HPES group, which is to be expr.nded, will have the
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process to improve efficiency majority of administrative responsibility for critiques.
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cf writing and publishing critique This change will provide additional available resources
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reports to assure completion of reports in a timely manner.
Procedures and programs will be revised to reflect this change.
Publish formal guidance for A IMSO governing the performance of briefs on upcoming work is performing briefs on upcoming being prepared.
Input is currently.being gathered from various work or events site departments on how PMSO should be worded. The PMSO is expected to be completed by July 15, 1990.
R2 view plan and resources for A review of the plan and resources was completed in February.
achieving procedural improvement Four contractors reported prior to May 1, 1990, to assist in goals reducing the backlog of comment forms. Four new procedure writer positions have been approved - these positions were filled by April 16, 1990.- This increase in manning and other actions implemented have been effective in reducing the backlog.
Continually encourage Traininz
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This is a performance criterion which is routinely evaluated operators to verify through during simulator training. In some instanc:s annunciator and all available means that the indication status must specifically be ut.11 zed to determine plant is responding as expected plant / equipment status.
to operator actions
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Shift / Assistant Shift Supervisors ha re begun to reaffirm with operators, on a continuing basis, that indications are being monitored and the plant is responding as expected to their actions.
QA The audit procedure and surveillance checklists are
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being revised to require that verification of indications is reviewed by QA. Revisions are expected to be completed by August 31, 1990.
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VII.
CONCLUSIONS
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o SIGNIFICANCE o
CORRECTIVE ACTION
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E5cALATED ENFORCEMENT IS NOT WARRANTED L
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U.S. NRC REGION 111
CLlhTON
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ENFORCD M CONFERENCE
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MY 31,1990
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EA 90-100
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50-461/90009
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REGION !!! 0FFICE
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GLEN ELLYN, ILLINDIS
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CLINTON ENFORCEKh7 CONFERENCE AG90A PAY 31,1990
1, lh7RODUCTION OF NRC STAFF:
EIMARD G. GREEFF %N, DIRECTOR, DIVISION OF REACTOR PROJECTS-r
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11. PURPOSE OF FEETING:
EDWARD G. GREFWAN I
111. NRC CONCERNS:
EDWARD G. GREEN %N IV.
CHRONOLOGY OF EVENTS: PHILIP BROCA w, SENIOR RESIDENT INSPECTOR
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ANALYSIS OF SAFETY SIGNIFICANCE:
PHILIP BROCH%N
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l VI SWMRY OF APPARENT VIOLATION:
PHILIP BROCWAN
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VII. LICENSEE PRESENTATION AND DISCUSSION:
ILLINOIS POWER COWANY
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Vill. CLOSING REPARKS: EDWARD G GREEN M N
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DISCUSS THE NRC DRoe CONCEP/S wim THE EVEhT.
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DISCUSS WE EVENT CHRONOLOGY, SAFETY SIGNIFICANCE ANALYSIS, IJO
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ASSOCIATED APPARENT VIOLATION,
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REVIEW AfD DISCUSS WE 1.lCENSEE'S PRESENTATION ON EVEhiPERSPEC H4 p
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NRC CONCERNS
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AWARENESS AND CONTROL OF PLAffT CONDITIONS.
B.
FAILURE OF RO OR STA TO PURSUE C0tCERNS ON ABNORf%L PLAfiT RESPONSE.
C.
lxK OF SRO WERSIGifT OF COMPLEX AND SAFETY SIGNIFICANT PLAf(T EVOLUTIONS BY "lNEXPERIENCED" f0 DURING STARTUP.
D.
SCHEDULING AND C0ifTROLLiNG COMPLEX AND SAFETY SIGNIFICANT PLANT EVOLUTIONS DURING SHlf T TURNOVER.
E.
SHIFT IMPOSED EMPHASIS ON SCHEDULE VERSUS SAFETY DRIVING PLANT
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OPERATIONS.
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FAILURE OF TWO ROS TO NOTE Bf4S OPEN DURING PANEL WALKDOWNS.
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FAILURE OF THE OPERATORS AND THE STA TO FOLLOW PROCEDURES.
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FAILURE TO ADEQUATELY COMMUNICATE PLANT PROBLEMS TO SENIOR j
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CHR0 0 LOGY OF april 11,1990, CONTROL ROD WITHDRAWAL EVEh7 APRIL 11, 1990
- J APPROX!PATELY THE MIDNIGH" SHIFT WAS WITHDPAWING CONTROL RODS
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MIDNIGin TURBINE WAS ROLLED
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SYNCHRONIZED GENERATOR
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GENERATOR LOAD BYPASS VALVES (BFY) CLOSED
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REACTOR POWER RAISED ABOVE LOW PWER SETPollR OF
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ROD PATTERN CONTROL SYSTEM (RPCS).
CR WITHDRAWALS STOPPED.
6:45 A.M.
OPERATORS RESUME CR WITHDRAWAL TO RAISE REACTOR
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MULTIPLE INDICATIONS OF OPENING BFY NOT OBSERVED
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BY REACTOR OPERATOR (RO), SHIFT TECHNICAL ADvlSOR (STA) OR THE LINE ASSISTANT SHIFT SUPERVISOR (LASS)
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STA RAISED FIRST CONCERN OVER LACK OF GENERATOR
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LOAD INCREASE
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REACTOR POWER REACHED-(APPROX) 35%
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B W HOTED OPEN BY B ' PRIME' RO, BUT SIGNIFICANCE.
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WAS NOT RECOGNIZED
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A RO AND' RELIEF COMPLETED PANEL WALKDOWih FAILED;-
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TO NOTE OPEN B WS I
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8:33 A.M.
- B R0'S IDENT!FIED OPEN BWS DURING SHIFT TURNOVER'
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8:34 A.M.
MIDNIGHT SHIFT A R0 RAISED GENERATOR LOAD SET,-
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BWS BEGAN TO CLOSE
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8:36'A.M.
BWS CLOSED
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SHIFT SUPERVISOR (SS) DIRECTED THAT GETARS RECORDS
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BE EXAMINED TO DETERMINE IF RODS WERE PULLED
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WHILE B WS WERE OPEN-
10:00 A.M.
GETARS RECORDS INDICATED AT LEAST 14 CONTROL ROD-
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WITHDRAWALS WERE MADE WITH A B W OPEN
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EVFNT SAFETY SIGN!FICANCE ANALYSIS
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1%SES FOR TECHNICAL SPECIFICATION 3.1.l4.1
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THE ROD WITHDRAWAL LIMITER SYSTEM INPUT ?0WER SIGNAL ORIGINATES FROM THE FIR j
STATE TURBINE PRESSURE, WHEN OPERATING WITH THE STEAM BYPASS VALVES OPEN,-
THIS SIGNAL INDICATES A CORE POWER LEVEL WHICH IS LESS THAN THE TRUE CORE POWER. CONSEQUENTLY, NEAR THE LOW POWER GLTP0lNT AND HIGH POWER SETPolNT OF THE ROD PATTERN CONTROL SYSTEM (RPCS) THE POTENTIAL EXISTS FOR NONCONSERVATIVE l CONTROL R0D WITHDRAWALS. TO ENSURE THAT FUEL SAFETY LIMITS ARE NOT VIOLATED,-
THIS SPECIFICATION PROHIBITS CONTROL R0D WITHDRAWAL WHEN A BIASED POWER SIGNAL i
EXISTS AND CORE POWER EXCEEDS THE SPECIFIED LEVEL.
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ALL CONTROL ROD WITHDRAWALS DURING THIS EVENT WERE IN ACCORDANCE Wilh THE
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REQUIRED PATTERN, WERE AT A RATE MORE CONSERVATIVE THAN WOULD BE ALLOWED BY THE RPCS,' AND WERE NOT NEAR THE HIGH POWER OR LOW POWER SETPOINTS.
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4 SAFETY SIGNIFICANCE I
DERIVED FROM LACK OF AWARENESS AND CONTROL OF PLANT CONDITIONS.
ACTUAL PHYSICAL SAFETY SIGNIFICANCE ON CORE - MiiOR.
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