IR 05000528/1987019
| ML17300A937 | |
| Person / Time | |
|---|---|
| Site: | Palo Verde  |
| Issue date: | 06/11/1987 |
| From: | Richards S, Zimmerman R NRC OFFICE OF INSPECTION & ENFORCEMENT (IE REGION V) |
| To: | |
| Shared Package | |
| ML17300A936 | List: |
| References | |
| 50-528-87-19-MM, 50-529-87-21, 50-530-87-21, NUDOCS 8706290033 | |
| Download: ML17300A937 (8) | |
Text
U.
S.
NUCLEAR REGULATORY COMMISSION
REGION V
Report Nos:
Docket Nos:
License Nos:
Licensee:
Facilit Name:
50"528/87-19 50-529/87-21 50-530/87-21 50-528 50-529 50-530 NPF-41 NPF-51 NPF-65 Arizona Nuclear Power Project P.
0.
Box 52034 Phoenix, AZ. 85072-2034 Palo Verde Nuclear Generating Station Units 1,
8 3.
Heetin Location:
NRC Region V Office, Walnut Creek, California Meetin Conducted:
May 11, 1987 Approved By:
merman, nior Re dent Inspector S.
Ri ard
, Chi
,
nginee ng Section D
e igned H rr D te igned 8706290033 870bi2 PDR ADOCN, 05000528
f
DETAILS 1.
Meetin Parti ci ants:
Nuclear Re ulator Commission (NRC J. Martin, Regional Administrator D. Kirsch, Director, Division of Reactor Safety and Projects
.R. Pate, Chief, Reactor Safety Branch R.
Zimmerman, Senior Resident Inspector, PVNGS C.
Sorensen, Project Inspector, PVNGS M. Davis, Palo Verde Project Manager, Unit 3 Arizona Nuclear Power Pro
'ect (ANPP)
E.
Van Brunt, Jr.,
Executive Vice President J.
Haynes, Vice President, Nuclear Production M. Ide, Corporate equality Assurance Manager R. Butler, Director, Technical Services 0. Zeringue, Technical Support Manager T. Shriver, Compliance Manager J. Driscoll, Assistant Vice President, Nuclear Production Other Licensee management and supervisory personnel participated in the meeting on May ll, 1987.
2.
Mana ement Discussion:
A management meeting was held on May 11, 1987, at the NRC Region V
Office in Walnut Creek, California.
The meeting agenda is presented as Enclosure 2.
Mr. Martin opened the meeting with a statement regarding the mutual benefit received in technical discussions of this type, and indicated that recent plant performance, especially with regard to personnel errors, raised a question as to how well the licensee was learning from experience.
Mr. Van Brunt, Jr.
acknowledged the comment and added that ANPP is committed to improve its operation by learning from past experiences in an'effort to be as good a performer as possible.
The discussion was then focused on plant performance indicators at Palo Verde, with emphasis on licensee event reports (LERs),
personnel errors, reactor trips and engineered safety feature actuations.
The improving performance trend during the third and fourth quarters of 1986 was noted to have been somewhat offset by a slight increase'n the number of LERs involving personnel errors during the first quarter of 1987.
Although the increase was due in part to a number of events of relatively minor safety significance, such as late fire watches, it was emphasized to the licensee that several of the LERs dealing with missed surveillance tests and communication difficulties between departments should serve as important indicators to management that close attention remains necessary in order to maintain the level of improvement seen to
f
date.
Mr. Martin added that it may become more difficult with time to reduce personnel errors as attitudes and personal work habits become better established in the years following initial operation.
Mr.'eringue provided a program overview of-the post trip review, root cause analysis and inter-department event investigation processes, concluding that development and enhancements made to these processes have improved the quality, thoroughness and timeliness of reviews into off-normal events.
It was stated that three individuals have thus far been trained in INPO's human performance root cause evaluation program, and that ANPP is continuing to visit other licensee's to discuss the implementation of similar event investigation processes.
The next issue discussed dealt with the licensee's evaluation of recent plant problems, including the corrective actions initiated.
Details associated with Unit 2 pressurizer level control problems during the latter part of May, 1987, were presented by Mr. Zeringue.
The cause of the level control problems (sluggish response)
was determined to have resulted from partially plugged orifices in the variable leg sensing lines to the two level transmitters.
The variable leg taps enter from the bottom of the Pressurizer, and the 7/32 inch orifices were found while flushing to be partially blocked with magnetite.
Following the flushing operation, the level control system response was restored to normal.
The licensee stated that a
modification to install standpipes at the variable leg taps in the Pressurizer lower head is being developed for all three units to preclude a similar occurrence.
A reactor trip at Unit 2 which occurred on April 16, 1987, was then reviewed.
The trip resulted, while attempting to isolate an electrical ground, when power was removed and then restored to a control element assembly calculator (CEAC).
Upon restoration of power the CEAC broadcast the maximum penalty factor to the core protection calculators (CPCs), resulting in high local power density reactor trip signals from all four CPCs.
The licensee determined during the post trip review process that although not contacted by Operations prior to removing/restoring power to the CEAC, members of Computer Engineering were aware of the potential for invalid penalty factors being communicated to the CPCs upon restoration of power to an in-service CEAC.
The licensee is also developing specific ground isolation procedures for high risk instrument buses.
Inverter reliability was questioned following an abnormally high number of DC fuse failures in Units 2 and 3 ~
The licensee has implemented changes to the control logic circuit cards in accordance with vendor recommendations in an effort to improve reliability.
Although the modifications appear in the short term to have improved inverter performance, the licensee is evaluating the possibility of inverter redesign or replacement, if necessary in the future.
Mr.
Martin expressed concern over the various quality-related problems experienced, including several instances where wrong components were apparently supplied by the vendor on control circuit cards.
Mr.
Martin stated that the inverter difficulties appeared to warrant
S
attention from the highest levels of management within the utility and the supplier in an effort to ensure reliability of the inverters in the future.
Nr. Butler provided information on the technology transfer and reliability programs, including scope and schedule.
The licensee has initiated a technology transfer program for ANPP engineering personnel in the areas of NSSS/BOP, transient accident analysis, and fuel design technology.
This program includes formal training, design basis manual preparation, on-the-job training (i.e.
walkdowns)
and document maintenance and control.
The licensee has also started a reliability and risk analysis program which includes the development of a probabalistic risk assessment, a component failure data base, an INPO plant performance indicator program, and an availability improvement program which is intended to identify systems and components in which single failure could result in a reactor trip.
The reliability and technology transfer programs are expected to be completed by 1988 and 1990, respectively.
Brief discussions were also held on the licensee's simulator upgrade and fidelity improvement goals, and problems experienced at Unit 1 as a result of radioactive material, including antimony, in the secondary system following the steam generator tube leak.
Nr. Ide provided the current status of guality Assurance (gA)
Department involvement in evaluating the adequacy of post event reviews, including reactor trips. It was noted that gA has increased its "reactive" overview of plant transients and off-normal events.
gA monitoring of backshift hours were also expected to be increased in the near future.
Nr.
Van Brunt, Jr. also provided a
description of the recently instituted Management Observation Program which set policy for unannounced management observation of plant activities during off-hours.
In closing, Nr. Martin stressed the importance that management take the necessary steps to ensure that they have a true understanding of work habits on off-hours to ensure company policies are adhered to in the same fashion as would be expected on day shift.
Additionally, Nr. Martin stated that he wished to discuss the status of the inverter problems further after additional licensee and supplier evaluation had been complete il II tl f