IR 05000320/1989003
| ML20246H283 | |
| Person / Time | |
|---|---|
| Site: | Crane  |
| Issue date: | 05/09/1989 |
| From: | Cowgill C NRC OFFICE OF INSPECTION & ENFORCEMENT (IE REGION I) |
| To: | |
| Shared Package | |
| ML20246H271 | List: |
| References | |
| 50-320-89-03, 50-320-89-3, NUDOCS 8905160058 | |
| Download: ML20246H283 (9) | |
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i U.S. NUCLEAR REGULATORY COMMISSION
REGION I
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' Report No.
50-320/89-03 Docket No.
50-320 License No.
DPR-73 Priority Category C
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Licensee:
GPU Nuclear Corporation P.O. Box 480 Middletown, Pennsylvania 17057 Facility Name: Three Mile Island Nuclear Station, Unit 2 Inspection At: Middletown, Pennsylvania Inspection Conducted:
March 5 - April 21, 1989 Inspectors:
T. Moslak, Senior Resident Inspector D.'Johnso, Resident Inspector Approved by:
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C. J. Cowgill, Chief, React Prcjects Section 1A Date Inspection Summary:
Areas Inspected: The site inspectors conducted routine safety inspection oi'
defueling and decontamination activities, including the proper implementation of radiological controls and housekeeping measures, and licensee actions on previous inspection findings.
Results: The licensee conducted defueling activities in a controlled manner, Aggressive measures have been taken by the licensee to control the spread of loose surface contamination and minimize personnel exposure to hot particles.
The circumstances were examined surrounding an incident which resulted in a crane cable snagging:a metal plate, causing the pir.te to fall and damage the roof of a decontamination facility located in the reactor building. The in-spector did note a weakness in the licensee lifting program to ensure that com-ponents/ material stored in the reactor building did not interfere with polar crane operation.
In general, licensee's actions were considered to be adequate
' to assure a similar incident did not occur.
Four previous inspection findings were closed, based on inspector review for current applicability and licensee actions to resolve the issues, k
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f TABLE OF CONTENTS PAGE 1.0 Introduction and 0verview............................................
I 1.1 Licensee Activities.............................................
I 1.2 NRC Activities..................................................
I 1.3 Persons Contacted...............................................
2.0 Defueling/ Decontamination Activities (NIP 71707).....................
2.1 Scope of Review.................................................
2.2 Inadvertent Entanglement of Polar Crane's Power Cable...........
2.3 Control of Hot Radioactive Particles............................
3.0 Licensee Action on Previous Inspection Findings (NIP 92701/92702)....
(Closed) Inspector Follow Item (320/84-24-01): FH-V-1A/8 Leaka 3.1 Contro1......................................................ge
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3.2- (Closed) Violation (320/84-09-01): Failure to Post Violations Identified in Inspection Report 50-320/84-04..................
3.3 (Closed) Violation (320/87-15-01): Halon System not Properly Returned to Service...........................................
3.4 (Closed) Violation (320/87-15-02): Inadvertent Transfer from the Borated Water Storage Tank (BWST).............................
4.0 Exit Meeting (NIP 30703).............................................
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DETAILS 1.0 Introducti,n and Overview 1.1 Licensee Activities Progress continued to be made in cutting and removing sections of the lower core support assembly (LCSA) to provide access to the lower reactor vessel head for defueling. Using the plasma arc torch, de-
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fueling crews completed cutting the fifth and final plate of the
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LCSA, the elliptical flow distributor (EFD), on March 31, 1989.
Following cutting of the EFD, a series of vertical cuts were made to the core baffle plate to facilitate their eventual removal.
Prior to baffle plates removal, the pieces of the EFD must be first lifted out, in order to defuel the lower head of the vessel. After this debris is removed, the baffle plates will be unbolted with a hy-draulic wrench and taken out. About 800 bolts will be untorqued to permit this.
Removal of the baffle plates will then provide access to remove debris from the annular region behind these plates.
Presently, defueling crews are using a hydraulically operated saw to sever support posts located on the periphery of the LCSA.
Cutting of the support posts enables core debris to be removed from inside the post. Additionally, cutting of the posts eliminates potential inter-ferences during eventual defueling around the periphery of the LCSA and the lower head.
1.2 NRC Staff Activities The purpose of this inspection was to assess licensee performance while conducting defueling and decontamination operations. The in-spectors made this assessment through observations of licensee ac-
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I tivities, interviews with licensee personnel, and review of applic-able documents. NRC staff inspections use the acceptance criteria and guidance of NRC Inspection Procedures (NIP's).
These NIP's are annotated in the Table of Contents to this report.
1.3 Persons Contacted l
During this inspection, the following key licensee personnel provided substantial information in the development of the inspectors' find-ings.
- J. Byrne, Manager, TMI-2 Licensing
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G. Kuehn, Site Operations Director, TMI-2
- S. Levin, Director, Defueling
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- A.
Miller, Technical Analyst Senior
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- M. Roche, Director, TMI-2
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R. Rogan, Director, Licensing & Nuclear Safety TMI-2 i
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- E. Schrull, TMI-2 Licensing Engineer
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- D. Turner, Director, Radiological Controls
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R. Wells, Licensing Engineer
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- Denotes Attendance at the final management meeting.
2.0 Defueling/ Decontamination Activities 2.1 Scope of Review The inspector observed and/or reviewed. licensee defueling/decon-tamination activities to: (1) ascertain factual status of such ac-tivities, and (2) assure proper adherence to applicable procedures.
The inspector also made observations in facility spaces with respect to proper housekeeping, fire protection, and radiological controls.
The general acceptance criteria for this review was Section 6 of TMI-2 Technical Specifications (TS).
In performing the above inspections, the inspectors focused on the following areas of licensee performance:
control of operations in progress by supervisory personnel;
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knowledge of the task by technicians and support persons;
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appropriateness of governing documents, including procedures and
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Radiation Work Permits (RWP's);
alertness of various controlling station personnel;
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assess the quality of implementation of selected evolutions witnessed; and, assess the material condition of the plant.
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2.2 Inadvertent Entanglement of Polar Crane's Power Cable On April 11, 1989, during the course of using the polar crane for a routine transfer of material within the Reactor Building, the crane's festoon (power) cable inadvertently became caught on a metal plate that was stored atop the Reactor Vessel Head Service Structure. The 260 pound plate was carried off of the service structure and fell, about twenty (20) feet, collapsing a section of the roof of the Decon Facility. The facility was unoccupied and no personnel were injured.
The load on the crane was safely landed and the crane was removed.
from service pending the outcome of an investigation of the incident.
The festoon cable is 2 power cable to the polar crane's trolley, that
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hangs beneath the trolley. The licensee promptly conducted a cri-tique to establish the cause of the incident and identify corrective actions to be taken to preclude a similar incident.
The licensee's immediate actions were:
restacking materials located on the service structure to an
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elevation below the bottom of the festoon cable catenary.
placing a height marker on the service structure and a maximum
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stack height indicator which provides at least one foot of clearance to the festoon cable.
identifying other potential interferences and installing height
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indicators providing at least a one foot clearance.
performing an operational check and a usual inspection of the
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polar crane and festoon cable.
Upon completing the immediate corrective actions, the licensee con-cluded that the polar crane could be returned to service.
In addi-tion, several actions were identified that would require further evaluation of the incident from an engineering and human factor per-speccive. These ongoing activities were:
reviewing the festoon design to determine if there was a means
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to control the height of the cable's catenary examining existing procedures to identify if operational steps
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should be changed or precautions added conducting an independent evaluation of the incident using a
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Human Performance Evaluation System (HPES) representative to establish a root cause and to provide any additional recommen-dations
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modifying the polar crane operator and signalman briefings to incorporate a review of the applicable procedures and lessons i
learned from the incident.
Because of the potential safety significance of this issue, the in-spector conducted an independent review of the event to ensure the plant was operated in accordance with applicable station procedures.
From interviews with licensee representatives, review of relevant documents, and examination of the scene of the incident, the inspec-tor determined that the licensee acted in a timely manner to estab-lish the circumstances resulting in the incident and to implement i
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corrective actions. The inspector.did note a weakness in the licen-see lifting program to ensure that components / material stored in the reactor-building did not interfere with polar crane operation.
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Through the review of licensee's immediate response and long term actions,.the inspector concluded that the licensee acted prudently to
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systematically evaluate the causes contributing to the incident and
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'to take prompt measures to assure an-incident of a similar nature does not occur.
2.3 Hot Particle Control Program Due to the unique nature of defueling operations at TMI-2, measures taken to contain loose contamination and, in particular, hot (radio-active) particles is of paramount importance in minimizing doses re-
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ceived by personnel. While conducting defueling operations and when performing the various supporting tasks of maintaining and repairing the associated tools and equipment; fine debris has clung to sur-faces, has been trapped in tool crevices,.or has been otherwise transported to work areas on the shielded work platform or tool de-contamination and repair areas.
Such relocation has the potential for causing significant personnel skin contaminations if measures are not rigorously implemented to contain and monitor such contamination and to improve work practices to restrict the relocation of.such material.
During this inspection period, the inspector reviewed various aspects of the licensee's radiological controls program to determine the measures taken to control hot particles. This review was. conducted by observing defueling operations in progress, and supporting tasks performed in the contamination control corridor / anteroom area to the reactor building and personnel access facility (PAF); interviewing licensee representatives from the Radiological Controls Department, and Defueling Operations Department; and examining licensee records relating to contamination control.
Through this review, the inspector determined that licensee manage-ment has continued to provide support and dedicate resources to this effort.
Evidence of this commitment included:
Establishing conservative goals for keeping individual whole
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body doses to less than 3 rem per year and consequential (those greater than 10 mrem per incident) hot particle doses to less than four per month.
Restructuring the Radiation Work Permit (RWP) format to be
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easier to understand and follow.
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l Tasking the Radiological Controls Department to evaluate all i
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new/ modified tools used for defueling to minimize sources for i
communicating hot particles
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'Providing seminars, including.in-house videotape productions, on
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contamination control techniques'for workers / supervisors.
Through discussions with' members of the licensee's Radiological Con-trols Department and observation of work practices, the inspector determined that the licensee has continued to evaluate and implement H
engineering controls and to modify plant areas-to improve performance
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in controlling loose contamination.
Recent measures taken to reduce
.the possibility of skin contamination and personnel exposure to hot particles included:
using.a high. efficiency vacuum cleaner to remove loose con-
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tamination from~ personnel exiting the reactor building, prior to removing the protective clothing / respirator placing a floor grating with installed ventilation system on the
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floor of the contamination control corridor to collect any loose contamination that may be freed when personnel are doffing. pro-tective clothing / equipment using a high efficiency vacuum cleaner for spills that may occur
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in the reactor building relocating the whole body frisking station closer to the exit
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point relocating the dressing area from the turbine building to the
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auxiliary building, making it closer to the radiological con-trolled area testing the effectiveness of disposable gloves, booties, and
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skull caps in reducing personnel contaminations.
Such. innovations are indicative of a concerted effort to upgrade per-formance.
From this review, the inspector concluded that licensee management has aggressively supported a hot particle control program and has~ dedicated resources to implementing administration and engi-neering measures to minimize personnel exposure to hot particles.
However, the overall effectiveness of these measures is contingent upon their conscientious implementation by supervisors, technicians, and workers'as part of the day-to-day work practices.
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1 3.0 Licensee Action on Previous Inspection Findings 3.1 (Closed) Violation (50-320/84-09-01): Failure to Post Violations Identified in Inspection Report 50-320/84-04
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Failure to post previous NRC violations within a two working day period as required by 10 CFR 19.11 was determined. The licensee i
acknowledged the oversight and subsequently posted the violation accordingly. This violation was attributed to an oversight by the licensing engineer responsible for posting Notice of Violations. As a result, personnel in the TMI-2 Li:ensing Section were reinstructed regarding the requirements in order to preclude further violations of this type. The inspector determined that the licensee's actions have been effective. This item is closed.
3.2 (Closed) Inspector Follow Item (320/84-24-01): FH-V-1A/B Leakage Control Post refurbishment tests indicated that leakage through the fuel transfer tube gate valves (FH-V-1A/B) was greater than design speci-fication.
The licensee's short term action to mitigate leakage through the FH-V-1A/B for the time period when the refueling canal is filled but Fuel Pool
"A" is dry was to fabricate and install blind flanges. This temporary mechanical modification adequately stopped leakage during the period when the Fuel Pool "A" was kept dry.
These flanges were removed prict to flooding Fuel Pool "A" at which point valve leakage was no longer a concern. This item is closed.
3.3 (Closed) Violation (50-320/87-15-01): Halon System not Properly Returned to Service The inspector discussed circumstances surrounding this event with licensee representatives and reviewed applicable records. The in-spector determined the corrective actions documented in LER 87-11 were implemented and that these actions provide assurance that a similar event will not occur. The inspector had no further questions
regarding this event. This item is closed.
i 3.4 (Closed) Violation (50-320/87-15-02): Inadvertent Transfer from
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l Borated Water Storage Tank (BWST)
As described in Inspection Report 87-15, a valve line-up was per-formed to refill the Fuel Transfer Canal (FTC) from the Processed Water Storage Tank (PWST-2).
This line-up was performed in accord-ance with Temporary Change Notice (TCN) 4210-3524-87-47 to Operating Procedure 4210-0PS-3524.05.
The valve line-up specified in this procedure requires that containment isolation valves PW-V-069 and PW-V-098, which are in the Borated Water Storage Tank (BWST) flow-path, be closed prior to opening valve FCC-V-11. However, the Shift Supervisor deviated from the sequence of the procedure by having a
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workerLin.the Reactor Building open FCC-V-11. When FCC-V-11 was opened, water from the BWST was. inadvertently transferred to the FTC.
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Approximately 3660 gallons of borated water were transferred.
The: inspector reviewed corrective actions generated by this event.
Included in this review was the revision to operating procedure 4210-OPS-3424.05 that clarified.the flowpath to indicate that valves PW-V-069 and PW-V-098 are part of the BWST flowpath.
The inspector
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4.0 Exit Meeting Thelinspector discussed the inspection scope and findings with licensee management at an exit meeting conducted on April 21,1989.
Licensee man-agement personnel attending the meeting are identified in paragraph 1.3.
The inspection results, as discussed at this meeting, are summarized in the results section of the inspection report.
Inspector Follow Items are matters which were established to administra-tively follow open issues based on inspector judgement or on licensee /
staff commitment, An Inspector Follow Item is addressed in Section -3.0.
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