IR 05000155/1986003

Insp Rept 50-155/86-03 on 860203-07.No Violation or Deviation Noted.Major Areas Inspected:Core Monitoring,Core Thermal Power Evaluation,Shutdown Margin Demonstration & CRD Performance Testing

ML20154A895
Person / Time
Site:	Big Rock Point File:Consumers Energy icon.png
Issue date:	02/25/1986
From:	Rescheske P, Ring M NRC OFFICE OF INSPECTION & ENFORCEMENT (IE REGION III)
To:
Shared Package
ML20154A886	List: IR 05000155/1986003 ML20154A883
References
50-155-86-03, 50-155-86-3, NUDOCS 8603040175
Download: ML20154A895 (5)

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U.S. NUCLEAR REGULATORY COMMISSION

REGION III

Report No. 50-155/86003(DRS)

Docket No. 50-155 License No. DPR-06 Licensee: Consumers Power Company 212 West Michigan Avenue Jackson, MI 49201 Facility Name: Big Rock Point Nuclear Plant Inspection At: Charlevoix, MI laspection Conducted: February 3-7, 1986 Inspector: s kW c25SG /

Date Approved By: , Chief E N Test Programs Section Date Inspection Summary Inspection on February 3-7, 1986 (Report No. 50-155/86003(DRS))

Areas Inspected: Routine, unannounced safety inspection of previous inspection findings, core monitoring, core thermal power evaluation, shutdown margin demonstration, and control rod drive performance testing. The inspection involved a total of 36 inspector-hours onsite by one NRC inspector including five inspector-hours onsite during off-shift Results: Of the five areas inspected, no violations or deviations were identifie !

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8603040175 860226 PDR ADOCK 05000155 G PDR i

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DETAILS 1. Persons Contacted

• R. Abel, Acting Plant Superintendent

• J. Alexander, Technical Engineer G. R. Boss, Technologist

• J. R. Kneeland, Reactor Engineer

• L. F. Monshor, Quality Assurance Superintendent The inspector also interviewed other licensee employees including members of the technical and operating staf * Denotes persons attending the exit meeting of February 7, 198 . Action on Previous Inspection Findings (Closed) Open Item (50-155/84-10-01(DRS)): Resolution of concerns regarding the frequency of picoammeter calibrations subsequent to a refueling outage. According to procedures S0P 1 and GOP 5, during ascents to power following a refueling outage, picoammeter calibra-tions are not required prior to 50% power (120 MWt). During a typical startup, reactor power can be rapidly increased to 50%. At about 120 MWt the reactor is brought to a stable condition, a heat balance calculation is performed, and the picoammeters are calibrate The 50% power level appears to be an acceptable point at which to perform the first calibratio Procedures 50P 1 and GOP 5 further state that heat balance calculations are to be performed daily during reactor operation. Contrary to this, Procedure T1-09 requires the calculations only above 50% power. The licensee has resolved the apparent conflict by revising all three procedure The requirements now state that above 50% power, a heat balance calculation will be performed each day; below 50% power, a calculation should be performed daily during steady state operatio The inspector has no further concerns in this are (Closed) Violation (50-155/84-10-02(DRS)): Procedure T1-09 was not strictly adhered t The procedure required that the heat balance be recalculated if the picoammeters differed from the expected readings (heat balance) by more than 10%. The licensee has deleted this requirement from the procedure since the basis for the 10%

could not be found. The revised procedure includes the use of a computer program as an alternate method for calculating a heat balance. Use of this program may improve the accuracy of the calculations and reduce the possibility of human erro However, hand calculations and the computer program are both acceptable methods for calculating an accurate heat balance. The inspector has no further concerns in this are . . . (Closed) Open Item (50-155/84 10-03(DRS)): Complete review of Facility Change FC-573. The modification involved installation of keyed selector switches and implementation of administrative controls to ensure that the thermal overload protection for six safety-related motor-operated valves is bypassed during all phases of plant operation except when the valves are subject to testing and maintenance. The basis for the modification was the NRC concern that the protective feature of the thermal overload relays could interfere with the safety function of the valve The licensee completed the required work and documentation on October 29, 198 The inspector has reviewed the modification package and verified that the administrative and regulatory requirements were satisfied, and that the testing and documentation was acceptable. The inspector has no further concerns in this are No violations or deviations were identifie . Core Monitoring The inspector reviewed the following documents to verify that the applicable requirements were satisfied and that the methodology was technically adequat BRP Cycle 21 Final Physics Package. This document includes the predictions and analyses for the Cycle 21 core design. Specific areas covered are: reload fuel and the core loading pattern, fuel bundle exposure and power distributions, thermal margins, reactivity limits, the control rod withdrawal sequence, rod worths, SCRAM functions, the power escalation rate, accident analysis, reactivity coefficients, the critical rod pattern, and transient analysi BRP Plant Manual Volume 15 - Technical Data Boo This document contains the current cycle data including the rod withdrawal sequence, graphs of the parameters required for a heat balance calculation, and other pertinent technical dat Cycle 21 - Core Status Boo This document and Procedure 16.3.2,

" Critical Configuration Prediction," provide the information necessary for determining the anticipated control rod pattern for an approach to critica The inspector noted that attention to detail was lacking in the analysis sections and discussed this concern with the licensee.

4 Cycle 21 - Core Follow Book. This document includes (1) exposure updates performed using the GROK computer code, and (2) the results of flux-wire runs. Procedure 16.3.5, "GROK Thermal-Hydraulic Analysis," datines the requirements in performing the exposure updates. Specific conditions at which.a GR0K analysis is required are: for each step of the control rod withdrawal sequence, for routine flux-wire analysis and incore monitor calibration, and for

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updating the exposure and void history arrays (about once per month). The-results of the GROK analysis include the most limiting

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value for.each of the following thermal limits: peak heat flux, maximum _ bundle power, MCPR (minimum critical power ratio),_and:

MAPLHGR-(maximum average planar linear heat. generation rate).. The, details of irradiating flux-wires.and the associated calculations and analysis are provided;in Engineering Procedure 16.3.6 and in the Instrument and Control Procedure TV-11-(BRP-RE-13). ~ Flux-wiie runs are required to be performed at every twenty notches of control rod movement or thirty effective full power days. Using.the information obtained from the runs, the incore flux monitors can be calibrated and the accuracy of the GROK computer code can be checked. .'The inspector noted the flux-wire runs from December 14 and 26, 1985, .

were not properly signed-off and reviewed. The licensee acknowledged this concern and corrective actions were immediately take No violations or deviations were identifie . Core Thermal Power Evaluation The inspector reviewed Surveillance Procedure T1-09, " Heat Balance Calculation," and the calculations performed since the beginning of Cycle 21, and verified that the surveillance frequency was satisfied. A heat balance calculation is required daily during operation ~and can be accomplished using either a computer program or a hand calculation. The results provide a basis for the calibration of the.out-of-core neutron monitoring system or picoammeters (power channels). Calibration is required if the actual picoammeter reading is.less than 97% of the expected reading (heat balance). The inspector verified _that the-licensee's methodology was technically adequate by independently performing a heat balance calculation on February 5, 1986. The results indicated that the reactor was at approximately 90% power and that the picoammeters were not in need of a calibration. The computer program was run as a check to the hand calculation and the results were identica The inspector noted that the procedure did not clearly state which portions of the calculations and results were to be completed, reviewed, and filed. The licensee acknowledged this concern and corrected the procedure. Other concerns identified by the _ inspector are discussed in Paragraph No violations or deviations were identifie . Shutdown Margin Demonstration The inspector reviewed Surveillance Procedure TR-43, " Shutdown Margin Check," and the results of the tests-performed prior to startup on October 19, 1985 (with the reactor head off). The shutdown margin'

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demonstration was accomplished using four different ' analyzed control rod configurations. Each case corresponded to pulling one of the four-strongest rods fully out and then withdrawing one adjacent rod far enough to add a minimum of 0.6% Ak/k in reactivity (a conservative administrative limit). The documentation indicated that the reactor remained subcritical:

throughout the tests, thereby demonstrating a sufficient shutdown margin

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17r Cycle 21 and satisfying the Technical Specifications. The inspector also reviewed the associated calculations and analysis provided in the BRP Cycle 21 Final Physics Package and verified that the methodology was technically adequat No violations or deviations were identifie . Control Rod Drive Performance Testing The inspector reviewed the following procedures and test results, and verified that the applicable requirements were satisfied and that an adequate testing methodology was used:

• Procedure TV-07, "CRD SCRAM Test from Notch '03' and Coupling Integrity Checks (Prior to Startup)," and the tests completed on November 6 and 17, 198 * Procedure TR-21, " Control Rod Drive Friction Testing Procedure," and the test completed on October 13, 1985 (with no ft.el in reactor).

• Procedure T7-03, " Control Rod Coupling Integrity Test at Power," and the tests completed on November 10 and 24, 198 * Procedure TR-01 (formerly T180-08), " Control Rod Drive Performance Testing," and the tests completed on October 6, 1985 (prior to startup, with no fuel in reactor). These tests included SCRAM timing, coupling integrity verification, control rod drive timing, and jog and position indicatio No violations or deviations were identifie . Exit Interview The inspector met with the licensee representatives (denoted in Paragraph 1)

on February 7, 1986. The inspector summarized the scope and findings of the inspection. The licensee acknowledged the statements made by the inspector with respect to the noted concerns. The inspector also discussed the likely informational content of the inspection report with regard to documents or processes reviewed by the inspector during the inspectio The licensee did not identify any such documents / processes as proprietar