ML20212E264

Annual Rept,Jan-Dec 1986

ML20212E264
Person / Time
Site:	University of Illinois
Issue date:	12/31/1986
From:	Micklich B, Pohlod C, Williams J ILLINOIS, UNIV. OF, URBANA, IL
To:	NRC OFFICE OF INFORMATION RESOURCES MANAGEMENT (IRM), Office of Nuclear Reactor Regulation
References
NUDOCS 8703040307
Download: ML20212E264 (8)

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ANNUAL REPORT JANUARY 1, 1986-DECEMBER 31,1988 ILLINOIS ADVANCED TRIGA FACILITY LICENSE R-115

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SUMMARY

OF OPERATING EXPERIENCE A. Summary of Usaae The reactor was scheduled for use 19.8 hours9.259259e-5 days <br />0.00222 hours <br />1.322751e-5 weeks <br />3.044e-6 months <br /> per week and was in operation 13.3 hours3.472222e-5 days <br />8.333333e-4 hours <br />4.960317e-6 weeks <br />1.1415e-6 months <br /> per week. This is virtually identical to the previous year, it was expected that usage would be up this year due to operator training activities involving Braidwood and Clinton. However these increases did not occur due to slippage of Clinton's fuel loading schedule and because of the status of Braidwood's Unit 2. Re-organization of the Nuclear Engineering Laboratory Courses has caused a temporary lull in undergraduate use of the reactor. In the following table, the per cent of time for different activities is given. Scheduled time is that time reserved for a given operation while operating time is from start-up to shutdown for the scheduled activity.

CATEGORY SCHEDULED OPERATING Research Projects 5.6% 3.4%

trradiations (samples) 64.8% 67.2%

Education and Training 20.3% 20.6%

Maintenance and Measurements 9.3% 8.8%

Presently there are three individuals with Senior Operator Licenses and one individual with an Operators License. The facility operates with a 40 hour4.62963e-4 days <br />0.0111 hours <br />6.613757e-5 weeks <br />1.522e-5 months <br /> week and the equivalent of two and a half full time operators and a full time reactor health physicist.

B. Performance Characteristics

1. Fuel Element Lenath and Diameter Measurements These checks were made on the B & C He Tgonals during the month of March. The pulse number at the time of the checks was 8452. For the eighteen elements in this region, there was a slight increase in the length (0.5 mils). The accuracy of a given measurement is estimated at t 5 mils. There was no change in the diameter of the fuel elements checked.

There were 133 pulses in 1986, bringing the total since 1969 to 8562. The values for pulse height, reactor period and fuel temperature were the same as measured 1.1 previous years.

2. Reactivity

, Control Rods: The measured values of the control rods have shown essentially no change. Variations between successive measurements are seldom greater than 5%.

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2 Core Reactivity: The loss of. reactivity, attributed to fuel burn up was 80.18 for the year. This value was determined by a comparison of the cold critical xenon-free control rod position at the beginning and at the end of the year. This determination takes into account the fact that two fuel elements were added to the core in November to recover some reactivity lost due to burn up. Based on an estimated 2 cents per MW-day of operation, the loss of reactivity would have been 8 0.17.

II. TABULATION OF ENERGY AND PULSING a

A. Hours Critical and Enerav Tvoe of Operation Time (hrs) Enerav (MW-hrs) 0-10 kW 220.8 0.04 10kW-250kW 152.9 32.60 250kW-1.5MW 242.8 164.39 Pulsing 50.3 0.88 Total 666.8 197.91 B. Pulsina Pulse Size Number 81.00-1.70 0 1.71-2.00 5 2.01-2.30 0 2.31-2.90 6 2.91-3.19 122 Above 83.19 0 Total 133 58ecause of the type of operation, the Hours Critical time includes instances where the reactor is not critical in the normal sense. These include the time to get critical during a start-up, the time between pulses during continuous pulsed operation and short periods of time during sample irradiations when samples may be removed or added.

til. REACTOR SCRAMS There were 26 unplanned scrams and no emergency shutdowns during this time period. These scrams were attributed to Instrument Malfunction (5):

Operator Error (19). External Causes (2). There were fewer than the usual number of scrams during 1986. This is attributed to the lower number of Nuclear Engineering students working with the reactor.

Linear Power (16)

This is a power level scram required by the Technical Specifications.

It occurs when the signal on any power range exceeds about 108% of that range. Almost all of these scrams (11) occurred as a result of switching errors. These errors involve turning the Range Switch the wrong direction or placing the Mode Selector Switch in Automatic at too low a power level.

Five scrams were caused by problems with the Linear Recorder pen drive

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motor.-Wear'due to age and use caused intermittent binding. This motor was replaced.

Period Scram (61-This scram is not required by the Technical Specifications. It occurs-when the period _is'3. seconds or less with the Mode Selector Switch in.

~ Automatic or Steady State position. Most of.these scrams (5) occurred when the period circuit was placed in operation at too low a power level.

Internal. characteristics of the Log-N Compensated lon Chamber caused the current' signal to be seen as a step increase in power when the Log-N.

Channel first began indicating at the low end of the scale. The period i ' circuit would then be placed into operation after reliable indication was obtained. Although this could be considered an Instrument Malfunction, it is considered an operator error because the scram was preventable by operator action. The problem was corrected with the replacement of the Log-N Chamber. One additional period scram occurred when the Mode Selector Switch was placed in the Automatic position at too low a power level.

Fuel Temnerature (2)

These scrams are caused by RF signals from CB transmitters being used

. near the Nuclear Reactor Laboratory. When the reactor is at high power i levels the RF signals are-large enough to cause a fluctuation in the

temperature indication circuit which can cause the channel reading to exceed'the scram set point.

Loss of Power (2)

!' One of these scrams was caused by the operator accidentally turning power off to the console by pushing the Power On/Off button instead of the Transient Fire button to initiate a pulse. The other scram resulted from a

. faulty oscilloscope probe being used to observe ripple voltage on +25 VDC power supply.

IV. Maintenance i 1t is estimated that about 480 hours0.00556 days <br />0.133 hours <br />7.936508e-4 weeks <br />1.8264e-4 months <br /> (40 hours4.62963e-4 days <br />0.0111 hours <br />6.613757e-5 weeks <br />1.522e-5 months <br /> per month) were spent on maintenance-related activities. However only 96 of these hours are j reflected in the Summary of Operations. These hours account for time when l

normally scheduled activities could not be carried out due to the need to make necessary repairs to the reactor system and for that time when the reactor was needed to perform surveillance activities. The significant items of maintenance are given below.

Control Rod Position Indicators: The position indicators for all four l

control rods were overhauled. This included replacement of drive belts, lubrication of moving parts, inspection for poor solder joints and

electronic measurements to confirm proper gain and voltages in the j amplifier circuits.

Coolina Tower Overhaul Both Cooling Towers were overhauled. This included replacement of the tower eliminators (baffles which act like 1

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4 moisture separators to prevent water droplets from being carried out of the cooling towers), sealing the basins to prevent leakage, replacement of temperature and level probes (as needed) and checks on the fans. One level sensor and one temperature-sensor,were replaced.

Radiation Monitorina System: A new radiation monitoring system was installed. This rystem is composed of four Viotoreen digital Universal Ratemeters with G-M tubes for detectors and a central control unit for processing the ratemeter output. Addition ut this system brings us to a total of nine area radiation monitors (three are required by Technical Specifications). ,

Water Box RTD Power Sucolv A solid state power supply was fabricated for this unit. The old unit was tube powered and tended to drift. This RTD monitors the water temperature of the primary water which is circulated through the domineralizer and was part of the original reactor equipment installed in 1g60.

Samole Handlina Tool The cabling, wiring and filter for the operation of the Lazy Susan Sample Handling device were replaced. The old cabling and wiring had become brittle and began to crumble. The tool relies on energizing a solenoid to release the samples. When the solenoid is de-energized, the filter network shunts the inductive spike.

Adiustable Transient Control Rod Position Indicator A silicon rectifier failed in the Adjustable Transient Rod Position Indicator. This failure caused excessive coasting of the indicator which made precise positioning of the Adjustable Transient Rod difficult.

Buildina Exhaust System: The flow switch in the building exhaust system was replaced because it became sluggish and actuated slowly. This switch triggers a warning that alerts the operator to a loss of building exhaust or that the valve that diverts air flow through the ban of charcoal filters has tripped.

Reactor Power Ranae Switch: A resistor that is mounted on the range switch for the 3 watt range failed. This was indicated by a full scale indication on the Linear Recorder when the Control Console was turned on.

Control Rod Position Interlock: A ra error in transposing the logic for this interlock to the actual hardware occurred in 196g when the present reactor was installed. This error went undetected until September of 1g86.

The wiring on the Magnet Up micro switch was changed to allow the Control Rod Position Interlock to function as intended. See Section V. Conditions Under Section 50.5g of 10 CFR.

Yarway Level Indicator Recenter: The Yarway Remote Water Level Repeater was overhauled and returned to service. It is an obsolete piece of equipment and replacement parts are hard to find. This unit acts as a back up to the Yarway Liquid Level Indicator which is visible to the operator through the Control Room window.

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5 Loa-N Channel: The Compensated lon Chamber for the Log-N Channel was

- replaced. The signal lead of the old chamber formed part of a low impedance path to ground when the current from the chamber was low. As a

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c" result of this when the Log-N Channel began to indicate, i t would do so ,

with a step increase.in signal that would be detected by the period circuit as'a short period. This would lead to a period scram. Replacement of this chamber 1 has corrected the problem. The problem with the old chamber appears to have been due to some contamination of the signal connector by'the glue from the tape which was rapped around the connector to protect i t when the old detector was installed.

V. Conditions Under Section 50.5g of 10 CFR-In May of 1986 the Nuclear Engineering Program became a department of the College of Engineering. In November the Department by-laws were approved. Coincident with this activity the Nuclear Reactor Committee carried out a 10 CFR 50.59 review of the change in structure which accompanied this change of status. As a result of this review, a request for an amendment to the Technical Specifications for the TRIGA was

- submitted to the Director Nuclear Reactor Regulation, USNRC. Action on this amendment by USNRC is pending. The Emergency Plan was reviewed, changes were made which did not weaken the plan and it has been accepted by USNRC. The same process is being applied to the Physical Security Plan.

Changes in status or in personnel are as follows: Dr. Barclay G. Jones has 2

been named Acting Head of the Department of Nuclear Engineering, Dr. John G. Williams, a new faculty member, has been named Reactor Laboratory Director. Mr. Neil Baras has been named Acting Reactor Health Physicist due to the resignation of Mrs. Elizabeth Thompson.

One new experiment was approved this year. This experiment involves placing optical material tangent to the reactor core in the Thruport. This material i s subjected to neutron and gamma bombardment. During and after each neutron pulse a small optical laser is shined through the material and an evaluation of the optical properties of the material i s carried i out.

With this experiment, evaluations of radiation hazards, procedures l . for making changes to the experiment, and shielding requirements foe the i experiment were reviewed and found to be satisfactory.

There was one change and one addition to the facility. The change involved the Control Rod Position interlock and is described in a letter

to Mr. Don Miller. Region ill USNRC dated 9/17/86 and the report of an

inspection conducted by Mr. T. N. Tambling of Region 111 USNRC, on 10/8/86 and dated 11/3/86.

i As described earlier, the addition of four area radiation monitors was accomplished. This system was ordered under bid specification requirements in 1985. These new monitors are of solid state construction and each unit has a separate power supply. The other unit is 26 years old, j electron tube powered and uses a common high voltage power supply for all

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~.V I . Release of Radioact'ive MateriaA Argon-41: Average concentration to environs via exhaust: 3.35E-8 uCi/mi Total releases 1154 mcl Monthly ranges.42-206 mCl

. Tritium: Estimation of 0.2 mci release from the.

evaporation of water-in the reactor tank.

This is based on the measured concentration of H-3 and water usage for-the year.

Effluent (sanitary sewer): Less than 0.35 uCi Vll. Environmental Surveys There were no environmental surveys performed in 1986 other than routine radiological monitoring. Contamination surveys are performed in the Laboratory. See Section Vill.

Vill. Personnel Radiation Exoosure and Surveys Within the Facility A. Personnel Eunosure

.Elghteen persons were assigned film badges at the facility. Three were full time employees, while the others averaged less than twenty hours per week in the facility. The badges are sent to Radiation Detection Company of Sunnyvale California on a monthly basis. The table below gives the whole body dose equivalent received by those who were assigned film badges during 1988.

Dose Eoulvalent (REMS) Number of Individuals No Measurable Exposure 11 0.01-0.10 5 0.10-0.25 2 Above 0.25 _1 Total 18 The highest Individual dose equivalent was 185 millirems. This was received by the Reactor Health Physicist who handles radioisotopes which are produced in the reactor and calibrates radiation monitoring equipment.

One other individual received a dose equivalent above 100 millirems. He received this dose equivalent as a result of handling radioisotopes.

Students and visitors doses are recorded on self-reading dosimeters and were less than 10 millitems.

B. Contamination Surveys Smear samples from various locations around the laboratory are taken

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at' periodic intervals. The removable contamination >ls determined by counting the smears with a gas flow proportional counter.

The maximum _ contamination is usually found in the vicinity where the irradiated sample containers are handled. There were 2.991 samples irradiated during the year, in the sample area the contamination varied from 2-14,328 dpm/100 cm* or 9.0E-07 to 4.5E-03 uCi/cs#, in the control room area the maximum was 35 dpm/100 cm* or 1.6E-05 uCl/cm*. Smears from other areas of the laboratory showed a maximum of 676 dpm/100 ces or 3.1E-04 uCi/cm a, IX. Nuclear Reactor Committee Dr. Bradley J. Micklich was appointed as Chairman of the Nuclear Reactor Committee for the 1986-1988 term. He is an Assistant Professor of Nuclear Engineering and has been a member of this committee previously.

The following members were re-appointed to the Nuclear Reactor Committee

Dr. A. M. Ougouag, Assistant Professor of Nuclear Engineering: Dr. James F. Stubbins, Associate Professor of Nuclear Engineering: Mr. Hector Mandel, Campus Radiation Safety Officer Mr. Craig Pohlod, Reactor i Supervisor (ex-officio). All are previous members of this committee. The j following changes to the committee were made in 1986:

1. Dr. Bradley J. Micklich replaced Dr. James F. Stubbins as Chairman of the committee.

l. 2. Dr. John G. Williams, Associate Professor of Nuclear Engineering l and Reactor Laboratory Director replaced Mr. Craig S. Pohlod as a

! voting member of the Committee.

3. Mr. Neil Barss replaced Mrs. Elizabeth A. Thompson as Reactor

. Health Physicist and ex-officio member of the committee. Mrs, f Thompson left the University of Illinois to take a position with the lilinois Department of Nuclear Safety.

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O Universit of Illinois W Putinent M CoHege d Enginaring

. Nuclear Engineering at Urbana-Champaign 214 Nuclear Engineering 217 333-2295 Laboratory 103 South Goodwin Avenue Urbana, IL 61801-2984 February 27, 1987 Director

. Office of Nuclear Reactor Regulation

'U.S. Nuclear Regulatory Commission Washington D.C. 20555 Attention: Document Control Desk

SUBJECT:

ANNUAL REPORT: lilinois Advanced TRIGA Reactor License No. R-115 Docket No. 50-151 The following is written to comply with the requirements of Section 6.7.f. of the Technical Specifications and the conditions of Section 50.59 of 10 CFR. The outline of the report follows the numbered sequence of section 6.7.f of the Technical Specifications.

Yours truly,

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Craig S. Pohlod Reactor Supervisor t -

dohn G. Williams Reactor Laboratory Director Bna 4 ) k W L Bradley J.'Micklich, Chairman Nuclear Reactor Committee

/N dd8 ff LL1tfo (

BarclayG.J/es,A Department,WfNucl(ppngHead at Engineering

, cc Regional Administrator, Region 111 USNRC poY f i

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