IR 05000528/1994099
| ML17311A581 | |
| Person / Time | |
|---|---|
| Site: | Palo Verde  |
| Issue date: | 01/12/1995 |
| From: | NRC OFFICE OF INSPECTION & ENFORCEMENT (IE REGION IV) |
| To: | |
| Shared Package | |
| ML17311A580 | List: |
| References | |
| 50-528-94-99, 50-529-94-99, 50-530-94-99, NUDOCS 9501190127 | |
| Download: ML17311A581 (14) | |
Text
PALO VERDE NUCLEAR GENERATING STATION SYSTEMATIC ASSESSMENT OF LICENSEE PERFORMANCE REPORT 50-528/94-99; 50-529/94-99; 50-530/94-99 I
INTRODUCTION The SALP process develops the NRC's conclusions regarding a licensee's saFety performance.
The SALP report documents the NRC's observations and insights on a licensee's performance relative to safety risk perspectives and communicates the results to the licensee and the public.
The NRC uses SALP results when allocating NRC inspection resources at licensee facilities.
This report is the NRC's assessment of the safety performance at the Palo Verde Nuclear Generating Station, from June 1,
1993, through November 30, 1994.
An NRC SALP Board, comprising the individuals listed below, met on December 6,
1994, to review and assess performance, in accordance with the guidance in NRC Management Directive 8.6,
"Systematic Assessment of Licensee Performance."
The Board developed this assessment for the Region IV Administrator's approval.
Board Chair erson J.
E. Dyer, Deputy Director, Division of Reactor Projects, Region IV Board Members T.
P.
Gwynn, Director, Division of Reactor Safety, Region IV S. J. Collins, Director, Division of Radiation Safety and Safeguards, Region IV E.
G.
Adensam, Deputy Director, Division of Reactor Projects-III/IV, Office of Nuclear Reactor Regulation II PERFORMANCE RATINGS This assessment was conducted under the revised SALP process implemented by the NRC on July 19, 1993.
Under the current SALP process, performance was assessed in four Functional areas instead of the previous seven functional areas.
The four areas are plant operations, maintenance, engineering, and plant support.
Safety assessment and quality verification were considered for each of the four functional areas rather than as a separate functional area.
Radiological controls, emergency preparedness, security, housekeeping, and fire protection were assessed under the plant support functional area.
The SALP category ratings continue to be used in the assessment of licensee performance in each functional area.
Improving or declining performance trends have been eliminated from the ratings.
9501190127 950112 PDR ADOCK 05000528 PDR
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Current Functional Areas and Ratings:
Functional Area Ratin This Period Plant Operations Maintenance Engineering Plant Support Previous Functional Areas and Ratings:
Functional Area Plant Operations Maintenance/Surveillance Engineering/Technical Support Radiological Contro'1s Emergency Preparedness Security Safety Assessment/guality Verification III PERFORMANCE ANALYSIS A.
Plant 0 erations Ratin Last Period 2 Improving 1 Declining Overall safety performance in the plant operations area continued to be good.
Toward the end of the assessment period management demonstrated strong leadership in aggressively addressing plant operations performance weaknesses and some improvements were noted.
However, challenges still exist in the conduct of operations, quality of programs and procedures, and operations ownership of plant conditions indicating that continued attention in these areas is warranted.
V Management recently.took aggressive actions to improve the conduct of operations at the site.
As part of the reengineering effort, the operations organization had been consolidated for all three units under a single manager and a Shift Manager position had been created to provide a dedicated, around-the-clock management oversight of shift activities.
Operating crews were reconstituted among the units to distribute operator talents, and management expectations were issued in the form of guiding principles and instructions for the conduct of operations.
These expectations were just being implemented at the end of the evaluation period and offered the potential for consistent and improved performance at all three unit Licensee programs and procedures for the conduct of opera'tions generally provided an appropriate level of direction for execution and coordination of activities.
However, some procedures, including emergency operating procedures (EOPs),
were cumbersome and difficult to implement.
The licensee focused considerable resources on improving the EOPs and plans to implement the completely rewritten EOPs in mid-1995.
In addition, an operability determination procedure was implemented midway through the assessment period.
Late in the assessment period, the licensee failed to identify that a letdown isolation valve, which had been leaking excessively, could not be assured of closure in the event of a fire in the control room.
This finding highlighted the need for continued improvement in the implementation of the operability determination process.
Early in the assessment period, the licensee took steps to address weaknesses in operator training which were manifested in initial and requalification examination failures.
High Intensity Team training focused on improving the formality of communication, command and control, team work, and operator understanding of the EOPs.
This training was found to be successFul.
Nonethe1ess, an initial license exam conducted late in the assessment period found that some candidates failed to take the necessary actions required by procedures in response to a simulated anticipated transient without scram event.
Additionally, on some occasions, operating crews demonstrated a lack of understanding of the Technical Specifications and other significant requirements.
A number of events during the assessment period highlighted weaknesses in the area of conduct of operations.
The two most significant events were related to the control of the reactor coolant system (RCS) where operator inattention to routine manipulations, complicated by hardware deficiencies, resulted in brief losses of inventory and reactivity control.
Recent changes to control room standards emphasized increased formality of communications, focused the attention of reactor operators on the control boards and the control room supervisor to the supervision of the operators, and reduced control room distractions by placing an operations/work control interface just outside the control room.
While NRC inspectors noted subsequent overall improvements, the fai1ure of a Unit 3 crew to ensure the proper alignment of RCS makeup sources prior to midloop operations at the end of the assessment period indicated that continued attention is needed to the conduct of operations.
Hanagement's response to emergent problems in the operations area was prompt and thorough in most instances.
A notable example was the licensee's thorough evaluation of the inadvertent opening of a containment spray valve. 'owever, the licensee was often slow to evaluate and address degraded equipment.
Throughout most of the assessment period, operators accepted taking manual actions to accommodate control room deficiencies and malfunctioning plant equipment as part of their routine activities.
Toward the end of the assessment period, licensee management focused maintenance resources to address these workarounds and redefined operator expectations to identify these deficiencies for priority attention.
As a result, operators have demonstrated a greater sense of responsibility and ownership for the condition of plant equipment.
The Nuclear Assurance organization was reengineered to provide consistent quality oversight of operations issues.
While increased
Nuclear Assurance involvement in operations activities was noted, the impact of their oversight has not yet been demonstrated.
The performance rating is Category 2 in the plant operations area.
B.
Maintenance Overall safety performance in the maintenance functional area continued to be good.
Senior management support was strong and well directed towards improving safety.
The recent consolidation of the maintenance function offers the potential to improve quality and consistency of support for all three units.
Maintenance craft skills were strong with very good troubleshooting abilities and team response to events.
The quality of work and material condition of the p1ant were good with a limited number of equipment challenges.
Maintenance self assessments were generally good, but implementation of corrective actions to eliminate root causes of equipment and performance problems needs improvement.
Senior management provided excellent leadership and strong support to maintenance of the three units.
Supervisory involvement usually assured that maintenance work was being performed properly and that there was good coordination of maintenance work activities with engineering and operations.
The recent organizational reengineering had initiated change throughout the maintenance organization with the potential to further improve work coordination, engineering involvement, and the efficiency of work performance.
Nevertheless, it was too early to assess the full impact of the reengineering on maintenance performance.
The overall material condition of the plant was good.
The units had operated well with a limited number of equipment challenges.
However, there remained a
significant number of minor deficiencies in the plants, some of which had not been documented as deficient.
For example, NRC inspectors found excessive fuel and lubricating oil leaks on both Unit 2 emergency diesel generators; there were numerous drip catches throughout the plants; and minor boric acid leaks were noted on numerous valves in the Unit 3 auxiliary building.
Historic problems such as control room annunciator deficiencies, operator work arounds, and the number of drip catches had been recently given priority for reduction; and initial results were promising.
Maintenance crafts exhibited strong skills, but occasional human performance errors were observed.
NRC observation of stork activities noted a generally thorough and deliberate approach with good teamwork displayed as evidenced during the recent online repair of an emergency diesel generator.
Maintenance training facilities with equipment mockups were well utilized for both the training of the crafts and the preparation for critical in-plant tasks.
Notwithstanding these strengths, work documents did not always provide complete guidance and crafts were occasionally found to ignore or overlook procedural requirements.
For example, craft personnel in Unit 2 worked on the wrong relay, even though the work instructions clearly specified the proper relay, resulting in parts of the Unit 2 containment being wetted.
These concerns were being addressed as part of the Maintenance Department reengineering and reorganizatio kl II
There were few problems identified in the surveillance test program.
Exceptions to this excellent performance involved occasions when the adequacy of surveillance activities was challenged by the lack of appropriate proceduralized acceptance criteria.
Excellent engineering support for the surve'illance test program was demonstrated in the recent Unit 3 mid-cycle outage for steam generator tube inspections by improvements in the efficiency of data acquisition which yielded superior eddy current data to support necessary steam generator repair work.
Recent troubleshooting and team response to events was very good.
For example, the planning and performance of an emergent repair to a leak in the Unit I spray pond piping was thorough and well implemented.
In another instance, the on-line repair of a loose stem coupling on a feedwater economizer valve was conducted quickly and efficiently with a detailed pre-job briefing that included a detailed discussion on contingency actions.
The failure to identify and replace a bent connecting rod in the Unit 3 emergency diesel generator was a notable exception to this performance.
The licensee demonstrated a good self-assessment capability in the maintenance area.
The Haintenance Assessment Program provided excellent performance feedback and self-assessments of plant material condition and corrective actions were thorough and self-critical.
Nevertheless, there were instances where the resolution of longstanding reliability problems were not aggressively pursued.
Examples included problems with the solenoid valves in the main steam support structure and the turbine-driven auxiliary feedwater pump steam admission valves.
The ability to identify and resolve root causes of material problems still needs improvement.
The performance rating is Category 2 in the maintenance area.
C.
~E Engineering performance was mixed during this assessment period.
The licensee demonstrated competence in performing generally thorough engineering evaluations, especially when management attention was focused on the issue.
However, a general weakness identified in previous assessment periods persisted:
management did not consistently ensure the timely and effective use of the engineering organization in resolving plant problems.
Recent organizational changes and relocation of engineering resources to the site offer the potential for improved performance in this area.
The licensee's initiative in several areas relating to the steam generator tube degradation has been noteworthy.
A comprehensive eddy current examination program has been implemented; steam generator chemical cleaning was conducted; various aggressive secondary water chemistry initiatives have been strengthened; and accident analyses were reviewed, and licensing documents developed, to support timely Technical Specification amendments to reduce the maximum reactor coolant system temperature.
The licensee was also proactive in reviewing old steam generator eddy current data and identifying possible defect r
The licensee's self-assessments, their definition of programs and their administrative control procedures were also considered strengths.
The inservice inspection program was well structured and controlled.
The aggressive verification and update of probabilistic risk data was also notable.
The licensee's HOV program was generally effective in establishing an assurance of design capability, and a related self assessment was comprehensive, raising substantive findings.
However, several other issues related to HOV's had weaknesses, such as an evaluation of a damaged motor operator torque switch, concerns with the diagnostic test data evaluation, and the use of nonconservative assumptions for stem friction coefficient.
Additionally, during a recent inspection, several aspects of the licensee's
CFR 50.59 safety review program were considered weak.,
In general, individual engineering performances showed evidence of a technically competent staff.
The licensee showed good initiative and developed a comprehensive action plan to address concerns with main steam safety valve testing.
Engineering progress was made in improving the performance and reliability of the feedwater and steam bypass control systems.
This included modiFications to the systems to ensure smooth and reliable operations.
Thorough reviews of reactor coolant sample valve cracking and steam generator water hammer events were performed after the NRC raised these problems to management's attention.
However, in several instances, the licensee did not aggressively assess deficiencies or pursue detailed root cause evaluations and corrective actions.
Regarding the Unit 3 emergency diesel generator operating with the bent connecting rod, the licensee management failed to critically assess the technical evaluations performed by the system engineers to support continued operation oF the diesel generator.
Also, system engineers did not aggressively pursue resolution of a cylinder's low compression readings.
Inspectors concluded that the licensee had missed several opportunities to identify and correct this significant degradation to the diesel.
Lack of aggressive resolution of unusual battery capacity indications in two cells led to the delayed identification of a degrading condition affecting all four class IE batteries in Unit 2.- Also, the licensee failed to thoroughly evaluate the impact of water hammer events on system components, which were caused by opening steam generator blowdown valves.
Other evidence of delayed responses to identified deficiencies were the untimely implementation of a comprehensive instrument out-of-calibration program, the lack of urgency in resolving environmental qualification issues, and the delayed evaluation of cracks observed in the valve bodies of two containment isolation valves.
Licensing submittals offered additional evidence of inconsistent engineering performance.
Technical Specification Amendment submittals regarding a safety valve setpoint issue were examples of an inadequate review of licensing submitta'Is.
Several other issues were indicative of poor prior planning, and a recent submittal concerning the refueling machine had an inadequate no significant hazards determination.
Also, the licensee was slow to recognize additional corrective actions necessary to be taken to correct deficiencies with Rosemount pressure transmitter l
Toward the end of the assessment period, the licensee's engineering organization was undergoing some significant changes as part of a complete reengineering of the site and corporate organizations.
Engineering personnel were being transferred to the site and functions realigned to better support site needs.
While this new organization has not been in effect 'long enough to be adequately evaluated, preliminary indications are positive.
The performance rating is Category 2 in the engineering area.
0.
Overall safety performance in the plant support functional area was determined to be good.
Excellent performance was noted in the emergency preparedness and security areas and good performance was noted in the radiological controls, fire protection and housekeeping areas.
Overall performance in the radiological controls area continued to be good.
Outage planning and preparation resulted in total exposures below the pressurized water reactor national averages despite mid-cycle steam generator inspection outages on each unit.
Proper staffing levels and qualifications were maintained for personnel responsible for implementing the radiological controls and chemistry programs, and an excellent radiation worker practical factors training course had been implemented.
Early in the assessment period several problems were identified with the implementation of the radiation protection program that were compounded by supervisors not getting into the radiological controlled areas to observe radiological work practices.
Toward the end of the assessment period, the radiological controls function for all three units was consolidated under one manager in a reengineered site organization with the aim of improving communications with the other departments and providing consistent support to all three units.
Since this reorganization, supervisory oversight, pre-job briefings and communications with other departments have improved.
However, deficiencies have been noted with the screening of contractor radiation protection technician qualifications, precautionary instructions in radiation exposure permits, and the number of long-term temporary shielding installations.
Performance in the areas of control of solid radwaste, transportation of radioactive materials, and water chemistry/radiochemistry confirmatory measurements were good.
Recent efforts in Nuclear Assurance audits of the radiological controls area appeared to be effective.
Performance in the emergency preparedness area improved since the previous assessment period and was considered excellent.
Corrective actions for problems identified, near the end of the previous assessment period during the steam generator tube rupture event on Unit 2 appeared effective.
The results from the operational status inspection indicated that the overall emergency preparedness program was maintained in a proper state of operational readiness.
Comprehensive quality assurance audits were performed in the emergency preparedness area.
A we')1 qualified and trained emergency response staff was maintained to implement the emergency preparedness program.
Emergency response faci'lities were well maintained and ready for activation with upgrades to the Emergency Operating Facility completed.
A good emergency response training program had been established.
Improvement items
1l l
identified during drills were properly tracked and corrective actions completed.
A FEMA graded exercise was not held during this assessment period; therefore, an annual emergency exercise inspection was not performed.
In the security area, excellent performance was noted during the last part of this assessment period after the security organization underwent significant organizational and management changes.
The security guard force was changed from a mixed contract/proprietary force to a predominantly proprietary force.
Corrective actions for deficiencies identified by the NRC early in the assessment period with compensatory measures for degraded systems and access authorization appeared to be effective.
Comprehensive licensee audits were performed in the security area and corrective actions were properly implememented.
System hardware improvements were completed including new monitoring cameras, and good test and maintenance programs were in place.
Security training instructors, firing range facilities and training support aids were excellent.
Overall, the fire protection program performance was good.
Good quality assurance audits were performed in the fire protection area that resulted in appropriate corrective actions for identified problems'he fire protection organization was sufficiently staffed with engineers and onsite fire fighters.
Fire protection personnel displayed strong ownership of their responsibilities by identifying several inadequacies in the fire protection system.
Mixed performance was noted in the housekeeping area.
Housekeeping conditions were noted to have deteriorated in some areas in Unit 3, including an excessive amount of debris from maintenance and cleaning activities.
Boric acid buildup was noted on various areas of the 3B high pressure safety injection pump.
Also noted were valve packing leaks, pump lube oil leaks, and steam leaks on the drain valve on the steam supply to the turbine-driven auxiliary feedwater pump.
Aggressive controls were implemented for transient material entering the Unit 2 containment during outage work.
Recently, improved housekeeping performance was also noted in all three units in that efforts were initiated to reduce the number of drip catches by tightening some valve packings.
The overall performance rating is Category 2 in the plant support are f, II I
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