IR 05000458/1989005

Insp Rept 50-458/89-05 on 890101-31.No Violations Noted. Major Areas Inspected:Operational Safety Verification, Radiological Protection,Security,Surveillance Test Observation & Maint Observation

ML20235S186
Person / Time
Site:	River Bend
Issue date:	02/24/1989
From:	Constable G, Ford E NRC OFFICE OF INSPECTION & ENFORCEMENT (IE REGION IV)
To:
Shared Package
ML20235S183	List: IR 05000458/1989005 ML20235S181
References
50-458-89-05, 50-458-89-5, NUDOCS 8903060192
Download: ML20235S186 (10)

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APPENDIX A U.S. NUCLEAR REGULATORY COMMISSION

REGION IV

NRC Inspection Report: 50-458/89-05 ,

Docket: 50-458 Licensee: GulfStatesUtilities(GSU) l P.O. Box 220 St. Francisville, Louisiana 70775 i

Facility Name: River Bend Station (RBS)

Inspection At: River Bend Station, St. Francisville, Louisiana Inspection Conducted: January 1 through 31, 1989 l'

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Inspector: -

29/P9 ~ i E. # Ford, Senior Resident Inspector, Project Da'te ' l S'ection C, Division of Reactor Projects l l

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l Approved: , __

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~G. L. Constable, Chief, Project Section C

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Division of Reactor Projects Inspection Summary l

l Inspection Conducted January 1 through 31, 1989 (Report 50-458/89-05)

Areas Inspected: Routine, unannounced inspection of operational safety verification, radiological protection, security, surveillance test observation, and maintenance observatio I Results: Operations personnel were cognizant of alarms in the main control area and shift turnovers were conducted in a complete and professional manne Operating procedures were properly utilize Inspection efforts on the standby liquid control (SLC) system represented a

" slice" of various activities (operator discovered deficiency, conduct of a SLC ,

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surveillance, maintenance on SLC instrumentation, and work package review and approval processing) spread out over the reporting period. These activities were properly conducted and performed in accordance with established procedures (cee paragraphs 5 and 6).

8903060192 890227 PDR ADOCK 05000458 G pnu l

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2-A GSU management decision to reduce reactor power and disconnect the main generator from the grid to fix a turbine electronics problem reflects a conservative attitude which may have precluded a turbine trip-reactor trip (see paragraph 4).

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E-3-DETAILS 3 Persons Contacted D. L. Andrews', Director, Nuclear Training

• J. E. Booker, Manager, Oversight E. M. Cargill, Supervisor, Radiation Programs

• J. W. Cook, Lead Environmental Analyst, Nuclear Licensing

• T. C. Crouse, Manager, Quality Assurance (QA) ,

• L. Curran, Cajun Electric Site Representative 1

• J. C. Deddens, Senior Vice President, River Bend Nuclear Group

• L. A. England, Director, Nuclear Licensing

• M. S. Feltner, Licensing Engineer A. O. Fredieu, Supervisor, Operations P. E. Freehill, Outage Manager P. D. Graham, Assistant Plant Manager, Operations D. E. Jernigan, Instrumentation and Control Supervisor G. R. Kinnell, Director, Quality Services

• R. J. King, Supervisor, Nuclear Licensing

• C. L. Miller, Compliance Analyst V. J. Normand, Supervisor, Administrative Services

• W.'H. Odell, Manager, Administration

• T. F. Plunkett, Plant Manager J.-P. Schippert, Operations Engineer

• K. E. Suhrke, Manager, Project Management R. J. Vachon, Senior Compliance Analyst J. Venable, Assistant Operations Supervisor The NRC inspector also interviewed additional licensee personnel during

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the inspection perio * Denotes those persons that attended the exit interview conducted on

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February 8,198 . Plant Status The reactor began its end of core life decrease in power (coast down) on December 2,1988. Power generation at the end of the inspection period was 83 percent. The coastdown rate is proceeding at the expected rate of-2 percent per week. The plant was separated from the grid over the weekend of January 15 and was synchronized back at 12 noon January 16, 1989, after troubleshooting and repair as discussed in paragraph The unit was in single loop operation January 18-21 while working on recirculation loop flow control valve problem . Licensee Event Reports (LERs) (92700)

During this inspection period the resident. inspector reviewed LERs for compliance with requirements established in 10 CFR 50. 73. Specifically, L______________________._______________ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _

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-4-the LER was reviewed for accuracy and clarity of the event description, the cause of each component and/or system failure or personnel error, the failure mode and effect each event had on plant operation, and operator ;

actions that affected the course of the event. Completion of corrective l actions for significant events were also verified. The following LER was reviewed:

o (Closed)LER(458/88-027): Inoperability of reactor core isolation cooling system due to an incomplete construction modification. This i event was described in NRC Inspection Report 50-458/88-26. It is considered an apparent violation and will be tracked in that report. This LER is close . Followup of Plant Events (93702)

Power Reduction Due to Turbine Circuitry: On Saturday, January 14, 1989, at approximately 2:30 a.m., the licensee received an alarm on the negative 125 VDC portion of the turbine supervisory system. Members of i the licensee's engineering staff, after consulting appropriate technical i manuals, contacted General Electric vendor representatives for consultation. Later in the day, plant management elected to reduce power from 86 to 70 percent power (plant in end-of-cycle coastdown). Previous l plant testing demonstrated that at this lower power level hydraulic transients would not cause RCIC/HPCS initiation in the event of ,

a main turbine tri l On January 15, 1989, a conservative decision was made to take the main !

generator off line to troubleshoot the circuitr Power was reduced and the unit was separated from the grid. The reactor was kept at approximately 12 percent power by using the bypass valves and steam drain A failed relay was replaced and the circuitry retested. At approximately 12 noon on January 16, 1989, the turbine was rolled and synchronized to the grid. A problem with a steam extraction line valve was resolved, and the unit commenced power ascension early that evenin The NRC inspectors discussed various aspects of the troubleshooting and repair process with operators and management personnel and witnessed portions of the power reduction and return to power. It was observed that the reduction was performed in accordance with General Operating Procedure G0P-0002, " Power Decrease / Plant Shutdown," and Abnormal Operating Procedure A0P-002, " Main Turbir.e and Generator Trips.

Automatic Depressurization System (ADS) Switch Pressure: During the reporting period, the NRC inspector responded to another NRC inspector's query regarding the use, at RBS, of static-o-ring (S0R) pressure switches installed to open safety / relief valves (SRV) in the low-low set (LLS)

mode. The purpose of the LLS made is to minimize cyclic stress on the containment due to relief valve cycling following a reactor isolation; one ADS SRV and four non-ADS valves are provided with additional opening and closing setpoints. These lower pressure setpoints override the normal

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-5-setpoints following the initial opening of the relief valves. They also act to hold these valves open longer, thus preventing more than a single valve from subsequently reopening. This system logic is referred to as  !

the " LOW-LOW SET" relief logic and functions to ensure that the containment design basis of only one SRV operating on subsequent '

actuations is me The concern of the query was that the SOR pressure switch used for LLS SRV logic did not meet TS setpoint accuracy requirements. The NRC inspector researched the operation of this portion of the automatic depressurization system'(ADS) and discussed the circuitry at RBS with licensing supervisors and cognizant design engineers. RBS does not use a pressure switch for this purpose. 'Instead, a Rosemont pressure transmitter and trip unit are used as inputs to the SRV logic. During the discussions, the methodology for setpoint determination was also reviewe ]

The NRC inspector independently verified licensee statements by a review of the following documentation:

o Cooper Nuclear Station LER 88-027-00; o Stone & Webster Engineering Corporation Set Point Data Sheet, J. )q l No.12210(2pages)1821*PSN616E,F; l

o Loop Calibration Report (LCR) No.1.ILADS.020, titled Automatic l

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Depressurization, Form No. WP-11, Rev. 0 (Equipment Data Card), and l l Form No. WP-04, Rev. 0 (Switch /Bi-stable Calibration Record) for Mark l No. IB21*ESN616E; j l I

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o General Electric Design Specification Data Sheet 22*A4G22AT, " Nuclear )

Boiler System," Rev. 12 (sheet No. 17); and  !

o RBS Technical Specification (TS) 3.4. The NRC inspector concluded from the above that, due to ADS sensor and circuitry differences, the TS required setpoint accuracy requirements appear to be met at RB No violations or deviations were identifie . Surveillance Test Observations (61726) l The NRC inspector observed and reviewed the performance of Surveillance  !

Test Procedure (STP) 403-0201, " Annulus Mixing System Monthly Operating Test"; STP-257-0201, " Standby Gas Treatment System Monthly Operability '

Test"; and STP-601-0201, "RWCU SLC Channel A, B Isolation Actuation." ,

o STP-403-0201, " Annulus Mixing System Monthly Operating Test,"

Revision 3, dated November 28, 1988. The' purpose of this test is to perform the monthly operability test of the shield building annulus mixing subsystems by initiating the subsystem from the control room I

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and verifying that the subsystem operates for at least 15 minutes as I required by TS 3/4.6.5.5.a when in Operational Condition 1, 2, or o STP-257-0201, " Standby Gas Treatment System Monthly Operability i Test," Revision 3, dated July 13, 1988. TS 4.6.5.4.a requires that l each standby gas treatment subsystem be demonstrated operable at l least once every 31 days by initiating, from the control room, flow I through the HEPA filters and charcoal absorbers and verifying that the subsystem operates for at least 10 hours1.157407e-4 days <br />0.00278 hours <br />1.653439e-5 weeks <br />3.805e-6 months <br /> with the heaters operable when in Operational Condition 1, 2, or o STP-601-0201, "RWCU SLC Channel A, B Isolation Actuation," Revision 3,

! dated April 28, 1988. This test is required by TS 3/4.3.2, " Isolation l Actuation Instrumentation." Specifically, Surveillance Requirement 4.3. i i and Table 4.3.2.1-1.4.h require the monthly testing of the reactor I

! water cleanup (RWCU) system isolation upon standby liquid control (SLC) I l system initiation when in Operational Conditions 1, 2, and 3. The

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purpose of this surveillance is to perform a (simulated) RWCU isolation using the SLC injection signa )

On January 5, 19S9, the NRC inspector observed the at-the-controls (ATC)

operator perform portions of this test at Panel P601. During the test, the SLC squib valve continuity light did not light satisfactoril This did not make the test unacceptabl It did, however, make the i

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test acceptable with coments. This was so indicated in the surveillance ,

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procedure data package and test results sheet. The NRC inspector

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noted, through observation and discussion, that a maintenance work order (MWO-128415) had been recently written (January 3,1989) and that this was recorded in the test results (see paragraph 6 for implementation of this maintenance work order).

In the above cases, the NRC inspector discussed the procedures with the technicians who were able to explain the technical intent of the procedure and had a working knowledge of the involved plant syste The test equipment being utilized was verified to be within its I calibration date. The NRC inspector noted that the control operating !

foreman (C0F) had granted permission to perform the test and the technicians conducted the test utilizing the latest revision of an approved procedure. Independent verification and lifted lead control were performed as required by General Maintenance Procedure GMP-0042,

" Circuit Testing and Lifted Leads and Jumpers." The test results were within the limits established by the plant's TS and they were reviewed and approved by the C0 ISI Testing STP-410-3302, " Control Building Chilled Water System Pump and Valve Operability Test," Revision 1, dated October 7, 1988. This test verifies pump operability by inservice inspection and testing as I

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required by TS 4.0.5. Additionally, it verifies system valve l operability by inservice inspection and testing as required by TS 4.0.5 for valves not tested by STP-410-3301 (Plant Chilled Water-Valve Operability). These requirements are applicable when in Operational Conditions 1 through 5 and when irradiated fuel is being handled in the primary containment or fuel building. The NRC l inspector observed testing being conducted on HVK Loop A (Pump, Discharge Valve, ar.d Check Valve Operability Test). Observations took place at the control room back panels where test control was exercised and data recorded and on Elevation 98 of the control building at the control building chilled water pumps (P1A and PIC),

dischargevalves(MOV20AandM0V200),andcheckvalves(V33and V34). The NRC inspector discussed the intent of the test and the procedural contents with the Field Engineer in charge of the conduct

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of the test. The procedure appeared to be adequate and was properly j adhered to by testing personne i No violations or deviations were identifie . Maintenance Observations (62703)

As discussed in paragraph 5, the NRC inspector noted the initiation of an MWO on the SLC system due to the unsatisfactory behavior of the squib valve white continuity light. To aid in understanding the purpose of the SLC River system and the Bend Licensed continuity Operator light,Manual Training the following)is (LOTM : excerpted from the l "The Standby Liquid Control (SLC) system is a redundant, independent

reactivity control system for use in the unlikely event that the l l

control rod drive system becomes inoperabl The system will shut I

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down and maintain the reactor subcritical when the reactor is cold and xenon free. The system consists of a storage tank, two suction valves, two 100 percent capacity pumps, two explosive actuated discharge valves, and the necessary valves, piping, instrumentation and control equipment required to inject the neutron absorber solution, into the reactor vesse SLC Discharge Valves The explosive discharge valves are double-squib (2 primers) actuated, shear-plug, zero-leakage valves. When either squib is fired, it drives a valve ram forward to shear off the integral cap of the inlet fitting. To open the valve, a low command current (2 amperes minimum) energizes a bridgewire that is imbedded in the explosive primer and fires the squib. The entire sequence of action occurs in approximately 2 milliseconds. Bridge wire continuity is monitored with a 10 millbmperes (maximum) curren The state of readiness of the explosive squibs contained in the trigger assembly of the valves is determined by establishing the L

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-8- j existence of continuity through the bridgewire network imbedded in each of the squibs (primers). The successful passage of a low level electric current through the squibs provides the necessary information. The level of the current must be kept low or inadvertent valve actuation will occur. Current limiting resistors placed in series with the squibs and the monitoring circuit l components provide the assurance that the 10 mA maximum safe testing current through the bridgewire network is never exceeded. The i monitoring circuit components, primarily a meter relay, depend upon l the presence of this low level current to keep from triggering the alarm circuit. Should the current fail for any reason, the alarm

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sounds and a white indicator goes out, i When continuity is lost, the meter's d'Arsonval movement falls back to a null position, allowing a light shield to interrupt a light beam I which was illuminating a switch. With the switch deactivated, a load relay becomes deenergized and the contacts change their state from closed to open and vice versa. The squib continuity lamps are extinguished and the control room annunciator is in its alarm state."

The Division I continuity light was observed by plant personnel to be behaving erratically during the performance of a scheduled STP. It was entered into the maintenance system on Maintenance Work Order (MWO) 12841 The MWO described the continuity meter as ". . . reading 4.9 rna on a 5 ma scale and intermittently spiking greater than 5 ma." When it spiked greater than 5 ma the " postage stamp" alarm, squib A-loss of continuity or power failure, flickered in and out. Division II SLC squib meter was j reading 4.1 ma during this same tim l The NRC inspector observed the troubleshooting and repairs of the involved circuitry by the plant I&C technicians on January 9,198 Troubleshooting revealed that the old meter had a partially burned bul This bulb is the light source for the light beam which works in conjunction with the light shield which in turn actuates a relay as previously described in the LOTM excerpt. The meter was replaced by a new bench-tested meter / relay. The NRC inspector discussed the technical aspects of the meter, its relay, and the associated squib firing circuit with operations and I&C supervisory personnel and the technicians performing the work. The NRC inspector noted the presence of QC personnel as required by the MWO traveler / inspection record package at the job site, the proper lifting and landing of leads as required by GMP-0042, the presence of calibration stickers on required test equipment, and a postmaintenance test for operability (STP 601-0201).

Later in the reporting period the NRC inspector reviewed the MWO package for timely and proper review (it was noted by the NRC inspector that the review process was still in progress at the time of the request). The following documents were reviewed:

o MWO R128415;

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. l o deficiency tag (properly removed from equipment) for 1C41*M600A; o maintenance briefing sheet; o work traveler / inspection record and continuation sheets; o equipmentsupplement(H&TEIDnumbers);

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o work performed statements and signoffs; o Attachment 2, Page 1 of 1, GMP-0042, " Lifted Lead and Jumper Tag Sheet"; and o various stores requisition form This inspection effort on a portion of the SLC system represents a " slice" of various activities (operator discovered deficiency, surveillance - with comments, maintenance, and work package review and approval) spread out over the reporting period. Each activity was properly conducted and performed in accordance with established administrative, surveillance, and maintenance procedure No violations or deviations were note . Operational Safety Verification (71707)

The NRC inspectors observed operational activities throughout the inspection period and closely monitored operational events. Control room -

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Proper control room staffing was maintained and access to the control room operational areas was controlled. Selected shift turnover meetings were observed and it was found that information concerning plant status was being covered in each of these meetings. Several control board walkdowns were conducted by the NRC inspectne In all cases, the responsible i reactor operators were cognizant as to why an alarm was lit and the reason for each plant configuration. Operational conditions and events, identified through discussions with the reactor operators and review of 1 the shift turnover logs, were identified in the main control room lo Inoperable equipment identified during the main control board walkdowns were identified by the applicable limiting condition for operatio The NRC inspectors conducted several tours of accessible areas of the facility during this inspection period. General housekeeping practices were found to be good. Walkdowns of the low pressure core spray (LPCS), .

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low pressure coolant injection (LPCI), and high pressure core spray (HPCS)

systems were conducted. Major flow paths were verified to be in the required standby position. The associated power supply for each major flow path valve and pump was observed to be available. No conditions were noted which would indicate the associated system would not perform its intended safety functio l l

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-10-The NRC inspectors verified that selected activities of the licensee's radiological protection program were implemented in conformance with facility policies, procedures, and regulatory requirement Radiation and/or contaminated areas were properly posted and controlled. Radiation work permits contained appropriate information to ensure that work could be performed in a safe and controlled manner. Radiation monitors were properly utilized to check for contamination. During plant tours the NRC inspectors frequently checked calibration stickers on various radiological monitoring equipment and physically verified that selected very high radiation area access control doors were locked and close The NRC inspectors observed security personnel perform their duties of vehicle, personnel, and package search. Vehicles were properly authorized and controlled or escorted within the protected area (PA). Personnel access was observed to be controlled in accordance with established I procedures. The NRC inspectors conducted site tours to ensure that i compensatory measures were properly implemented as required due to equipment failure or degradation. The PA barrier had adequate i illumination and the isolation zones were free of transient material The licensee operated the plant in a safe, controlled manner during this I inspection perio No violations or deviations were identified in this area.

l Exit Interview

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An exit interview was conducted with licensee representatives (identified in paragraph 1). During this interview, the NRC inspector reviewed the scope and findings of the report.

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