IR 05000259/1985020

Insp Repts 50-259/85-20,50-260/85-20 & 50-296/85-20 on 850321-28.Violation Noted:Failure to Perform Safety Evaluation Required by Plant Procedures

ML20127E308
Person / Time
Site:	Browns Ferry
Issue date:	04/23/1985
From:	Cantrell F, Patterson C, Paulk G NRC OFFICE OF INSPECTION & ENFORCEMENT (IE REGION II)
To:
Shared Package
ML20127E296	List: IR 05000259/1985020 ML20127E292
References
50-259-85-20, 50-260-85-20, 50-296-85-20, NUDOCS 8505200030
Download: ML20127E308 (4)

Text

-

UNITED STATES

'

-[p Itfubo

'

NUCLEAR REGULATORY COMMISSION

[' REGION ll y j 101 MARIETTA STREET, * *' ATLANTA, GEORGIA 30323

%...../

Report Nos.: 50-259/85-20, 50-260/85-20, and 50-296/85-20

• ,

Licensee: Tennessee Valley Authority 500A Chestnut Street Chattanooga, TN 37401

'

Docket Nos.: 50-259, 50-260 and 50-296 License Nos.: DPR-33, DPR-52, and DPR-68 Facility Name: Browns Ferry 1, 2, and 3 Inspection Conducted: March 21 - March 28, 1985-Inspectors: YM L." Paul k /// /

M //h2/fd DaYe Sfgned Y

C. A.'Patterson b 4ll21h

/// ' // Dite Signed Accompanying Perso ne C. R. Brooks Approved by:

-

1. 7 -

w F. S! C $trell, Section Chief

~'

'/ 3 !/ [

Dath Sfgned

'

Divisiof of Reactor Projects SUMMARY Scope:_ .This routine, unannounced inspection entailed 30 inspector-hours in the areas of operational safety concerning the High Pressure Coolant Injection (HPCI)

Syste 'tesults: One violation was identified: Failure to perform a safety evaluation required by plant procedure An enforcement conference was held April 8, 1985 (Inspection Report 50-259/85-24, 50-260/85-24 and 50-296/85-24).

8505200030 850430 PDR ADOCK 05000259 G PDR

-

,

.:,'

..

i

-

REPORT DETAILS

^

1 Persons Contacted Licensee Employees J. A.- Coffey, Site Director G. T. Jones, Plant Manager J; E. Swindell, Superintendent-- Operations / Engineering J. R. Pittmen,-Superintendent - Maintenance J. H. Rinne, Modifications Manager J. D. Carlson, Quality Engineering Supervisor

.D. C. Mims, Engineering Group Supervisor

.

- *

R. Hunkapillar, Operations Group Supervisor-C. G.: Wages, Mechanical Maintenance Supervisor T. D. Cosby, Electrical Maintenance Supervisor R. E.l Burns, Instrument Maintenance Supervisor T. L. Chinn, Technical-Services Manager

-

T. F. Ziegler, Site ' Services Manager lJ. R. Clark, Chemical Unit Supervisor

-

B. C. Morris, Plant Compliance Supervisor A. L. Burnette, Assistant Operations Group Supervisor R. R. Smallwood,: Assistant Operations Group Supervisor T. W.~ Jordan, Assistant Operations Group Supervisor S. R. Maehr, Planning / Scheduling Supervisor G. R. Hall, Design Services Manager

.'

.

W. C. Thomison, Engineering Section Supervisor A. L. Clement, Radwaste Group' Controller Other licensee'~ employees contacted included licensed reactor operators senior reactor operators, . auxiliary operators, craftsmen, technicians,

'

_public safety officers, Quality Assurance, Quality Control and engineering

. personne . ExitInterview(30703)

The inspection scope and findings were summarized on March 27, 1985 with the Site Director, Plant Manager and Assistant Plant Managers and other members

-

of the licensee staf The licensee acknowledged the findings and took no exceptions. The licensee did not identify as proprietary any of the materials provided to or. reviewed by the inspectors during this inspectio . High' Pressure Coolant Injection System Operability Inspection This special report covers the. findings of a routine followup inspection on-March 21, 1985, of an event occurring on March 4, 1985, on Unit 1. At

'9:05 a.m., on ' March 4, 1985, during the performance of Surveillance Instruction S.I. 4.5.E.1.c, High Pressure Coolant Injection (HPCI) System

-

.

C

,

2 Motor Operated Valve Operability, the HPCI system was declared inoperable due to a blown fuse in the direct current to alternating current inverter circuit (23-114, Drawing 730E928 ~ sheet 2). The inverter supplies power to necessary logic circuits during HPCI initiation. The fuse failure occurred during operation of the HPCI steam line drain to the main turbine condenser isolation valves (73-6A and 73-68). The fuse was replaced and several attempts to duplicate the problem by cycling valves 73-6A and 73-6B faile HPCI was declared operable by the licensee at 10:15 a.m. on March 4,1985 without further investigation. The 4-hour report to the NRC on March 4, 1985, listed the failure cause as unknown. No followup report has been made to date to NRC although a possible cause for the blown fuse was observed on March 8,1985, when the open resistor in the solenoid suppression circuit was identifie On March 5, 1985, a maintenance request (MR A-171114) was written to investigate possible voltage - spiking to the HPCI inverter circuit while cycling valves 73-6A and 73-6B. The MR was issued to check the surge suppression circuits of the valves which are connected in parallel with the inverter circuit on the common 250 VDC supply. These valves are solenoid operated energize to open valves. When the HPCI system initiates, the valves deenergize to isolate the system from the condenser path. As the-solenoid magnetic field collapses, it is suppressed by a parallel diode-

'

resistor network. During troubleshooting, the field suppression resistors (1500 ohm, 25 watt) were found open. The troubleshooting was completed on March 8, 198 No spare resistors were available and an attempt to procure parts from Unit 2 found one of the similar Unit 2 resistors also open. The Unit 2 resistors were, however, 10 watt instead of 25 watt resistors. The reason for the difference in wattage was unknown. The resistors in Unit 1 were not

replaced and the open resistors remained. The HPCI system was considered fully operabl The inspection followup in this area will remain an -

unresolved item * pending TVA's resolution of the resistor wattage question and inspection of similar field suppression circuits in similar valve circuits in all three units (259/260/296/85-20-01).

With these know deficiencies in the field suppression circuits of valves'

73-6A and 73-68, the HPCI system was considered operable by the licensee even though a safety evaluation as required by Standard Practice 17.18, Unreviewed Safety Question Determination was not initiated or performe Technical Specification 3.5.E.1.(2) requires HPCI to be operable. The unit

was shutdown for other reasons on March 19, 1985. A violation of Technical Specification 6.3.A occurred in that a safety evaluation was not performed after the discovery of the HPCI system deficiency as required by Standard Practice 17.18 (259/85-20-02). This violation was discussed with plant management in an exit meeting on March 27, 1985.

.

• Unresolved items are matters about which more information is required to deter-mine whether-they are acceptable or may involve violations or deviation .

'%

'

o

Other inspector concerns were identified during the inspection. Problems with the HPCI inverter circuit had previously occurred and were known to the licensee. A plant design request (DCR 2347) was written in October 1980, to replace the inverter .due to the unavailability of spare part Corres-pondence to the inverter vendor in June 1984 (Topaz, Static Inverter Model N500-GWRS-250-60-115) was. reviewed which discussed the type of fuse in the inverter which faile The fuse is internal to the inverter and is a 10 ampere Busman fuse. No aggressive corrective action was taken in the past to resolve these deficiencie The Topaz inverter circuit vendor manual was not treated as a controlled document and was in the cognizant engineer's desk drawer. The vendor manual recommended certain checks in the inverter circuit if a fuse failed. The inverter was not checked after the fuse failur The vendor manual recommended 5000-hour and annual preventive maintenance checks for the inverte Apparently, no preventive maintenance had previously been performed on the inverter. The vendor manual concerns were discussed with the plant superintendent for maintenance on March 25, 198 The licensee is developing and has previously committed to implement a vendor manual control program in response to IE Report 84-23. Inspection Report 84-50 discusses an inspection of the vendor manual program as required in Generic Letter 83-28. The corrective and preventive maintenance programs for the inverter circuit will remain an unresolved item pending further licensee record review (259/260/296/85-20-01).

.

.