IR 05000289/1991099
| ML20058P075 | |
| Person / Time | |
|---|---|
| Site: | Three Mile Island  |
| Issue date: | 10/15/1993 |
| From: | NRC OFFICE OF INSPECTION & ENFORCEMENT (IE REGION I) |
| To: | |
| Shared Package | |
| ML20058P072 | List: |
| References | |
| 50-289-91-99, NUDOCS 9310220064 | |
| Download: ML20058P075 (6) | |
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SALP REPORT - THREE MILE ISLAND, UNIT 1 BACKGROUND The SALP Board convened on August 12,1993, to assess the nuclear safety performance of TMI-1 for the period November 17, 1991 to July 31,1993. The Board was conducted pursuant to NRC Management Directive (MD) 8.6 (see NRC Administrative Notice 93-02).
Board members were Richard W. Cooper (Board Chairman), Director, Division of Reactor .
Projects, NRC Region I (RI); M. Wayne Hodges, Director, Division of Reactor Safety, NRC RI; Susan F. Shankman, Deputy Director, Division of Radiation Safety and Safeguards, NRC RI; and John F. Stolz, Director, Project Directorate I-4, NRC Office of Nuclear Reactor ,
Regulation. The Board developed this assessment for approval of the Region I Administrato The performance category ratings and the assessment functional areas used below are defined and described in NRC MD ,
I PERFORMANCE ANALYSIS - OPERATIONS Plant operations was rated a SALP Category 1, with a declining trend in the previous SALP period. Strengths included strong performance during power operations, a well trained and professional staff, and effective management directives and guidance that resulted in timely and comprehensive safety assessments of plant events. The declining trend was due to weaknesses in the operators' performance of infrequently performed activities during the 9R refueling outage. These weaknesses appeared to be primarily attributable to problems with procedural implementation and a lack of specificity in certain procedure Operators continued their strong performance during this SALP period responding to plant -;
transients, as well as controlling changes to plant conditions. Significant transients that challenged the operators included a dropped control rod, a fault on an off-site power line, a ground on an auxiliary transformer, a reactor coolant pump seal injection flow control valve failure, and an inadvertent partial actuation of the emergency feedwater system. The outstanding performance of operators in response to plant transients and changes to plant conoitions was indicative of a well-trained, professional, qualified staff. Close coordination between the Operations and Training departments resulted in a very high pass rate for both initial and requalification examinations during this SALP perio Extensive management oversight of daily activities continued and was expanded this SALP period by the addition of a third Senior Reactor Operator to each shift. These additional Senior Reactor Operators were responsible for direct supervision of Auxiliary Operators and monitoring of in-plant equipment, and allowed the Shift Foremen to concentrate on Control Room activitie Although the Operations department was appropriately involved in significant operational l
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decisions, several instances occurred that were indicative of a need for improved
) communications by Operations management and a need for improved formality relative to 9310220064 PDR 931015 jh ADDCK 05000289 Mi -
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procedural compliance. In one instance a reactor trip occurred when Operations management directed the removal of main condenser pressure switches from service without a procedure after being advised by Operations department personnel and Maintenance department supervision that the method chosen was nonconservative, in that it had the potential to simultaneously affect more than one pressure switch. In another case, there were differing opinions between the operating crew and Operations management on the need to test the Fuel Handling Building ventilation system fans after air flow in the system dropped below that required by Technical Specification (TS). Although the TS requirements were met following readjustment of the dampers and filter replacements, communications between the operations staff and Operations management were not effective in ensuring the proper restoration and verification of equipment operability. Another example involved Plant Engineering, the Plant Review Group, and the vendor recommending that the emergency diesel generater be run for one hour. This test run was also recommended in the operating procedure to deraonstrate Technical Specification operability with the other diesel out-of-service for periodic maintenance. Notwithstanding a later post-test review that confirmed the technical adequacy of a 20 minute test run on the machine, Operations management instructed the operators to run the diesel for 20 minutes without processing a formal change to the operating procedure, which was indicative of an informal attitude toward procedumi compliance. Because there were several examples of this problem that occurred over the SALP period, the recurrence of these problems was indicative of the licensee not having aggressively evaluated the singular events collectively to identify the root cause and implement corrective action to prevent recurrenc .
Instances of inadequate procedural guidance and controls contributed to errors by operations staff during this SALP period. A significant example involved the bypassing / isolating of both trains of the decay heat river water system to the decay heat closed cooling water system heat exchangers for a 3 hour3.472222e-5 days <br />8.333333e-4 hours <br />4.960317e-6 weeks <br />1.1415e-6 months <br /> period. Weaknesses also occurred in maintaining control of system alignments when valve manipulations were controlled through log entries in lieu of procedures. In one instance the Station Blackout Diesel Generator was rendered inoperable for one month due to a valve misalignment. These errors were indicative of informality in the licensee's approach to some activities and a heavy reliance on the knowledge and experience of the staf ,
In summary, overall performance in Operations declined this period. Strong performance by operators to plant transients and in controlling changes to plant conditions continued, with extensive management oversight and direct supervision. However, communications problems in the Operations organization, an informal attitude toward procedural compliance, and excessive reliance on the experience of the staff were noted during the SALP period, and ,
were indicative of a need for improved formality and teamwork in operating the plan The operations area is rated Category l l
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IIL PERFORMANCE ANALYSIS - ENGINEERING -
In the previous SALP period, the licensee was rated a SALP Category I because of excellent engineering support of operations and engineering involvement in all plant activitie Cooperation between site and corporate engineering, and competent personnel were also cited as strengths. A high backlog of engineering evaluation requests, field change notices, and infrequent site attendance at the corporate engineering meetings were identified as problem area In this SALP period, engineering continued to demonstrate strong safety perspectives and support of site activities. This was evidenced in the planning and direction for modifications of the spent fuel pool reracking, sleeving of additional lane wedge steam generator tubes, and reactor coolant pump vibration monitoring. The licensee demonstrated particularly strong engineering performance in the erosion-corrosion program, the unique use of 0.2 micron filters for the reactor coolant pumps and in the evaluation of the increased stroke time trend of the emergency feedwater pump steam admission valve. The new procurement engineering group performed well in dispositioning storeroom parts, evaluating replacement items and performing commercial grade dedication for equipment and part Outstanding progress was made in design basis reconstitution. Six design basis reviews were completed this period; this brings the total completed to fourteen. The licensee also completed two comprehensive safety system functional inspections of the high pressure injection makeup system and the low pressure injection system. These inspections provided good assessment feedback. Licensee management continued to support these inspections because of their assessment benefit There were two instances where more timely and detailed review of test data was neede Although design basis testing had been completed on 38 MOVs (a very noteworthy accomplishment), results of tests conducted in 1991 which showed 20% overthrust of a valve ,
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were not evaluated until NRC inspectors found the valve housing to be cracked in June 199 Also, in evaluating diesel generator end bearing wear, the licensee did not evaluate lubrication oil quality control for a number of months when laboratory results indicated potential external contamination. The bearing was in the early stages of degradation and did not have to be replaced immediatel Engineering evaluations and presentations in support of license amendment requests were of
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high quality and very detailed. The licensee's submittal to the NRC on an alternate method i
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to satisfy Radiation Embrittlement of Reactor Vessel Materials, Regulatory Guide 1.99, was based on a comprehensive search of surveillance data from other nuclear plants and on a good statistical analysis of the surveillance data. Although the submittal was still under review by the NRC at the end of the SALP period, the licensee displayed good in-house i
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engineering capability and understanding of the reactor embrittlement issu Excellent progress was made in meeting engineering action close out dates and in sizably l
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reducing the engineering request backlo In summary, Engineering continued to demonstrate strong safety perspectives and support of site activities. This was particularly evident in the erosion-corrosion program and in design basis reconstitution. The engineering request backlog was reduced substantially. Minor problems with timely review and evaluation of test data were encountere The engineering area is rated Category I PERFORMANCE ANALYSIS - MAINTENANCE Maintenance was rated as a Category 2 in the previous SALP. An experienced maintenance staff was identified as a major strength. A weakness was noted in the lack of preparation for surveillance tests and the controls used during test performance. Also, there was a :
demonstrated weakness in the area of maintenance procedure implementatio ;
The experienced maintenance staff continued to be a strength in this SALF perio Maintenance personnel were highly trained and knowledgeabk There was strong management support and involvement in maintenance activ s Strong emphasis on corrective and preventive maintenance contributed sign i to safe operation and high plant availability. There were no safety system actua90 , or forced outages attributable to maintenance or surveillance during the SALP period. Use of diagnostic techniques such as thermography and computer assisted diagnostics of the integrated control system resulted in ' ,
early detection and correction of plant equipment problems. The need for rework of corrective maintenance was very low. Equipment problems were trended and common causes for repeat problems were investigated. The physical condition of the plant was ,
excellen Maintenance procedure upgrades completed and implemented over the SALP period were well written. With a few exceptions these procedures were followed by maintenance
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technicians. With one exception, troubleshooting maintenance was well controlled and was well done. In the latter part of the SALP period, a troubleshooting procedure was developed to effectively formalize the process. Only two missed surveillances were noted in a well executed testing progra The identification of, cause for, and correction of personnel errors was not as well developed as the ability to identify and correct hardware failures. For example, a number of errors occurred in returning equipment to service following corrective maintenance and surveillance testing, particularly by Instrument and Control technicians. These errors included a building spray flow equalizing valve left open following a surveillance test, instrument air to a makeup valve operator left partially shut following corrective maintenance, and two instrument air valves to the EFW pump steam supply throttle pressure controller left open after corrective maintenance. There was a higher incidence of errors in returning equipment to service in the last six months of the SALP period. These resulted from a combination of
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In summary, maintenance was performed well and contributed to safe operation and high
plant availability. Preventive and corrective maintenance were particular strength Innovative use of diagnostic techniques allowed the early detection and correction ofincipient ,
problems. A strong root cause and trending program for hardware issues contributed to high performance and a well maintained plant. Errors in returning equipment to service following corrective maintenance and surveillance testing during the latter part of the SALP period were a concer t The maintenance area is rated Category j PERFOlGIANCE ANALYSIS - PLANT SUPPORT ,
This functional area is new, representing a significant change from previous SALPs. The
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Plant Support functional area covers all activities related to plant support functions, including radiological controls, emergency preparedness, security, chemistry, fire protection, and
housekeeping control In the previous SALP, all of the above areas rated were evaluated as superior, Category 1, because of management support, knowledgeable staff, effective training programs and strong program implementation. A weakness noted in the previous S ALP was the interdepartmental communications between the radiological controls, chemistry, and engineering staff In this SALP period, the activities included under this functional area continued to be conducted in an outstanding manner, significantly contributing to safe plant operation. In j
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particular, each activity continued to benefit from well-trained and qualified staff, management support, and strong program implementatio The Radiological Controls Department provided very good support of maintenance and h[
surveillance activities. This support was particularly evident during the control rod drive /
mechanism cooling water modifications and spent fuel pool reracking. The use of an .
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independent radiological assessor was a positive effort. The licensee's program to keep radiation exposure of workers as low as is reasonably achievable (ALARA) continued to l meet or exceed the challenging goals set by the licensee. The health physics training 1, program was well developed and well manage 'j
The licensee responded appropriately to a weakness in the measurement of beta radiation p!
fields during reactor building entries made at power. 12ter in the SALP, licensee personnel (
observed during an entry at power demonstrated improved performance in assessing beta radiation levels. However, the licensee was slow to implement proposed procedure changes
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- 6 to effect the improved measurement techniqu The emergency preparedness (EP) function was generally well implemented. Emergency response organization managers demonstrated a good knowledge level developed through training and an effective requalification program that covered lessons learned. Moreover, the licensee's strong training program included emergency preparedness program changes, table-top exercise, numerous station drills, and active drill participation. However, the February 1993 plant intrusion event highlighted some unanticipated response condition Foremost among these was a 47-minute delay in calling out emergency responders due to locking (as part of the response to the intrusion event) the office containing the dedicated, programmed callout phone The security organization continued to have plant management support for program improvements, suc51 as training in tactical response for security staff. The security
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organization responded very well to the intruder. The licensee performed thorough root cause analyses and developed technically sound and comprehensive corrective actions for weaknesses identified during the intrusion event. The effectiveness of the licensee's short-term actions was demonstrated when the licensee properly implemented an intruder drill late in the assessment period. The licensee subsequently took aggressive actions to strengthen the perimeter of the plant against similar intrusions. These initiatives, which are beyond current NRC regulatory requirements, were to be completed after the end of the SALP perio Fire protection and housekeeping received appropriate management attention and were considered very good. The licensee's fire protection program, including administrative controls, fire surveillance program, fire audits, fire training programs, firewatch and fire :
equipment preventive meintenance program, was satisfactorily implemented.
o In summary, despite the weakness related to emergency planning for a security event, excellent management support continued and several strengths were noted including qualified and experienced staff, generally effective training, and improvements to program implementation. Overall, the licensee's efforts resulted in superior plant suppor The plant support area is rated Category .