ML20072G686

Nuclear Energy Lab Annual Rept,1982

ML20072G686
Person / Time
Site:	05000142
Issue date:	12/31/1982
From:	Wegst W CALIFORNIA, UNIV. OF, LOS ANGELES, CA
To:	Bernard H Office of Nuclear Reactor Regulation
References
NUDOCS 8306280595
Download: ML20072G686 (21)

Text

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l' r ANNUAL REPORT t

i 1982

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!?- NUCLE AR ENERGY L ABOR ATORY it.

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SCHOOL OF Ef4GIflEERING AND APPLIED SCIEf4CE Uti!VERSITY OF CALIFORflIA, LOS AtlGELES hD $00b O! b $$2 R PDR

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NOMENCLATURE g

Ar-41 A radioactive isotope of Argon gas with a half life of 110 minutes I

CFH Cubic feet per hour 10 Ci Curie, the unit of activity equivalent to 3.7 x 10 d/s

-6 pCi 10 Ci CIC Compensated ion chamber 9

i GM Geiger-Muller ionizing radiation detector HEPA Filter A high efficiency particulate filter kWh Kilowatt hour (s) kWt Kilowatt (s) thermal Log N An instrument that measures the logarithm of the reactor power NEL Nuclear Energy Laboratory Port Hours The number of irradiation ports used times the number of hours utilized PRN-4 Type of neutron detector that reads out in rem

1. Scram A reactor shut-down f.f^

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CONTENTS Section Pm 1

1 REACTOR OPERATING EXPERIENCE 4

2 UNSCHEDULED SHUTDOWNS & REPORTABLE (ABNORMAL)

OCCURRENCES PREVENTIVE AND CORRECTIVE MAINTENANCE 6 3

FACILITY AND PROCEDURE CHANGES 9 4

5 RADIOACTIVE MATERIAL RELEASES TO THE ENVIRONMENT 10 l

' 12 6 ENVIRONMENTAL SURVEYS

• PERSONNEL 00SIMETRY 16 7

TABLES Page Number Reactor Usage (Operating Hours) 2 I

Research Usage (Port Hours) 3 11 14 III Location and Identification of Beta-Gamma Area Film Badges Quarterly Area Film Badge Exposures - 1982 17 IV f

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e Section 1 REACTOR OPERATING EXPERIENCE Reactor operations in 1982 provided 297 hours0.00344 days <br />0.0825 hours <br />4.910714e-4 weeks <br />1.130085e-4 months <br /> of services in 103  ;

reactor runs. The operational intensity can also be summarized as 185 equivalent full (100 kWh) power hours or 18.5 megawatt hours, a decline of about 23% from 1981.

Table I illustrates the reactor usage over the last five years in four broad categories.

. The bulk of the research work category derives from users external to the UCLA School of Engineering and Applied Science. As the research is dominated by service irradiations, and because several irradiation ports can be occupied in a single reactor run, the intensity of user demand in this category is appropriately summarized by port-hours of activity. One port, used for one hour, provides one port-hour. Table II illustrates port-hours of such usage in 1982 by user category.

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TABLE I Reactor U$ age (Operating Hours) 1978 1979 1980 1981 1982 CATEGORY 52 31 46 61 67 CLASSROOM INSTRUCTION 5 2 3 8 DENONSTRATIONS 7 178 335 295 284 203 RESEARoi 34 1 38 16 19

1. %1NTE!@NCE

• 271 372 381 364 297 TOTAL OPERATING HOURS 203 294 289 239 185 EQUIVALENT FULL POdR HOURS 20.3 29.4 28.9 23.9 18.5 PEGAWATT-HOURS CLASSROCN INSTRUCTION COMPRISES USE OF THE REACTOR IN SUPPORT OF UCLA LFOERGR/DUATE NO GRADUATE LABORATORY WORK INVOLVING BASIC COUNTING, ACTIVATION N/ALYSIS, REACTOR PAPp.ETER DETERMIPATIONS, MO OPERATOR TRAINltf,. OPERATOR REQUALIFICAT! Ort IS INCLUDED IN THl5 CATE-GCRY. HOURS ARE REACTOR OPERATING HOURS IN SUPPORT OF CLASS INSTRUCTION.

DEMONSTRATIONS #tE OF VARIOUS KIM)S; THEY ARE PERFORMED FOR EDUCATIONAL GROUPS NO OTHER e

TOUR GROUPS.

' RESEARCH IS A BR(MD CATEGORY DCNINATED BY SERVICE 1RRADIAT10NS IN WHICH Trf REACTOR 15 USED AS A TOOL WITrOUT REFERENCE TO REACTOR THEORY OR OPERAT10t4AL PROPERTIES MAINTEtGNCE REPRESEPR W gab FOR WHICH THE REACTOR IS OPERATED FOR CALIBRATION PURFOSES, M O DOES NOT 10

• 1 4 e :NTEtdNCE HOURS.

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TABLE II Research Usage * (Port Hours) 1978 1979 1980 1981 1982 USER CATEGORY

. 67 18 6 101 4

UCLA ACADEMIC USERS 105 91 OTE R INIVERSITIES 53 20 38 6 37

& COLLEGES 95 264 360 211 100 OTER EXTR#ULAL USERS 9 1 27 113 130.5 EL STAFF 246 409 508 429 382.5 TOTAL PORT MARS 1

1. RESEARCH USE E OF THE REACTOR IS DOMINATED BY SAMPLE !RRADIATIONS. CERTAIN NEL STAFF RESEARCH DOES NOT INVOLVE SAMPLE !RRADIATIONS.

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. Section 2 UNSCHEDULED SHUTDOWNS & REPORTABLE (ABNORMAL) OCCURRENCES Unscheduled Shutdowns The four unscheduled shutdowns experienced in 1982 are briefly described in the following paragraphs.

A high flux scram occurred at approximately 200 watts when the reactor was being taken to power to test the newly installed Dual Linear Amplifier that replaced the original Safety Amplifier. The reactor shutdown as it should have when the Dual Linear Amplifier output reached 125%. The reactor was restarted and the chambers adjusted in sta.ges until the reactor power and the Dual Linear Amplifier both agreed at 100 kW.

A newly installe'd HEPA filter in the reactor core vent line was placed too close to a high radiation detector. The detector, sensing radiation emitted from the argon-41 in the filter, initiated a ventilation system shutdown and scram. The problem was corrected by

- reducing the concentration of argon-41 in the core vent line. The reduction was accomplished by displacing much of the core air with dry nitrogen.

A momentary disruption of building power caused the reactor to shutdown during a student orientation run. The reactor was returned to power for the completion of the run.

A loss of power to the primary pump caused the reactor to shut down on a drop rods scram. The reactor was shut down until the

'd defective pump relay could be isolated and replaced.

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Reportable Incidents / Abnormal Occurrences On June 30 during an initial approach to critical, the reactor operator was unable to take the reactor critical due to the constant engagement of the auto controller. The problem was traced to a failed diode in the inhibit surveillance circuit which is normally engaged by the auto control switch (see Section 3, Inhibit Surveillance Circuit).

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• Section 3 PREVENTIVE AND CORRECTIVE MAINTENANCE The annual calibration and tests were completed by February first. The semi-annual calibrations of the radiation monitoring equipment were performed in January and July.

The maintenance performed on various reactor subsystems or components is summarized in the following paragraphs.

Area Radiation Monitors

. A remote indicating meter was incorporated into the calibration track which utilizes the south area monitor cable to facilitate the calibration process. Also a new high voltage modular power supply replaced the original power supply which had failed earlier and was being powered by an external power supply.

Argon-41 Monitor The Keithley model 640 vibrating reed electrometer failed, and had to be sent to an authorized Keithley repair center for repairs.

- The process took 5 months. A Keithley model 417 picoammeter was substituted for the model 640 in the interim. With the substitution of the Keithley 417 picoammeter for the Keithley 630 vibrating reed electrometer, an offset correction graph had to be constructed. Using the correction graph during the mid-year calibration of the system, agreement between the original calibration and the mid-year calibration was within 3%.

Auxiliary Air Compressor The reactor auxiliary air compressor's unloader and check valve I were replaced with a Load Genie after the unit failed, which prevented 6

the unit from starting under load.

Secondary Effluent Monitor

• The secondary effluent monitor required frequent adjustment primarily because it is very temperature sensitive. Control room air conditioning failure in the summer coupled with heater failure in the winter caused severe drifting of the zero setting. The frequency of handling the unit compounded the maintenance problem in the form of broken cables, and readjustments of the high voltage and the single channel amplifier.

Flow Meter Indicator The primary and secondary flow meter indicator was disabled when a wire connected to the unit's function switch broke. The unit was repaired and returned to service after a thorough check.

High Radiation Monitor What appeared to be a failure of the high radiation monitor turned out to be an actual reading of 25 mr/hr (see Section 2). The alarms were changed from the self resetting to the latched mode so that there would be no doubt as to what caused the ventilation f- shutdown. A second failure occurred as a result of a burned out fuse.

l Inhibit Surveillance Circuit During a prestart check, what appeared to be a failure of the l

Auto / Manual Circuit was traced to the failure of a coupling diode in the Inhibit Surveillance Circuit. The Radiation Use Committee

- recommended that the type of transient suppression previously incorporated into the rod drive circuits be provided in this circuit.

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Log and Linear Chart Recorders New chart drum and clutch assemblies were installed in both the linear and log chart recorders.

Primary Pump Two unrelated failures of the primary pump system occured in consecutive order. The first involved the failure of the relay contacts that power the pump. Replacing the relay solved the problem.

- The second failure occurred when the coupling between the primary pump and the pump motor loosened resulting in a loss of primary flow.

Reinstallation of the coupling corrected the problem.

Rod Position Indicators Rod 4 position indicator stuck at 80% although the rod could continue driving up until the up limit light came on. Once the indicator was cleared, the unit worked properly. However, as a precaution, the entire circuit was checked out and a rod withdrawal and drop test was conducted before the system was declared operational.

A ground wire failure on the Rod Position Indicator' adjustment circuit which is mounted on a hinged door prevented the zeroing of all rod position indicators. Replacing the ground corrected the problem.

Start-up Channel The lack of carry pulse from the unit's decade to the ten's decade was corrected by tube replacement in the Start-up Channel. l Temperature Recorder Replacing a power tube in the servo amplifier of the temperature

• recorder caused the sluggish unit to function in a normal manner.

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Section 4 FACILITY AND PROCEDURE CHANGES The following changes were made for the year 1982 Equipment:

1. The original Safety Amplifier was replaced by a Dual Linear Amplifier manufactured by General Atomic.

2. A running time meter connected to the magnet power circuit was installed in the console.

3. A closures scram point test circuit was installed in the log recorder to allow the operator to test the circuit without having to force the recorder above the 1 watt mark.

4. A HEPA filter was installed in the reactor core air extract line.

5. Pending the repair of the Keithley model 630 vibrating reed electrometer, a Keithley model 417 picoammeter was substituted for the model 630. A spare model 417 and the model 417 used as the reference-

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channel were substituted as the system was refined to reduce the noise

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. l evel . Five months later, with the repair of the model 630 completed by the Keithley authorized repair center, the argon-41 system was restored to its original configuration.

6. The Inhibit Surveillance and the Auto / Manual circuits were modified for transient protection as recommended by the Radiation Use

. Committee.

Procedures u

1. The Radiation Use Committee approved the Calibration of the Argon-41 Monitor Procedure during its meeting of June 15.

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Section 5 RADI0 ACTIVE MATERIAL RELEASES TO THE ENVIRONMENT Total Releases The total releases of radioactive material to the environment for 1982 were as follows:

A. Gaseous: Ar-41, 27 Ci B. Liquid: None C. Solid: None Gaseous Effluents The principal radioactive gaseous effluent as monitored in the building exhaust stack is argon-41. The actual concentration is determined by a 4.3 liter ion chamber which is calibrated in microcuries per milliliter versus ion current. This data is recorded on a strip chart recorder whenever the reactor is running. The data are periodically integrated using a compensating polar planimeter to obtain the total release.

The lower total release of radioactive gaseous emissions to the environment is attributed to two factors. The first being the decline by 23% of the total energy generated as compared with 1981. The second factor, the use of nitrogen gas as a sweep over the core to displace the air and hence the argon present in the atmosphere further reduced the emissions by another 20%.

Airborne radioactive particulate releases are monitored by a system that samples both the supply and exhaust air from the reactor e

room at the reactor room level (third floor, Boelter Hall). The system I over-collects particulates relative to isokinetic sampling 10

4 (ANSI N13.1 - 1969 Table Cl). The particulate filters are counted rountinely on a batch basis.

Equipment difficulties were experienced during the year, and actual fluctuations from week-to-week were appreciably larger than can be e counted for by counting statistics alone. This was true for both supply air and exhaust air. Of course some part of the fluctuations can be real and reflect seasonal changes, short period atmospheric e variations, and earth moving construction effects that influence the amount of natural radioactivity collected by this kind of sampling.

A statistical analysis of the weekly data for 1982 yielded the following estimates of annual average concentrations:

-13 3 C (exhaust) = (5.3 + 2.0) x 10 Ci/cm

-13 pCi/cm3 C(supply) = (3.9 + 1.2) x 10

-13 pCi/cm3 AC = (1.4 + 2.1) x 10 4

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Section 6 ENVIRONMENTAL SURVEYS The reactor room is almost completely surrounded by a controlled buffer zone of limited access. The unrestricted public area is exterior to the laboratory boundary. Although environmental measurements (wipe tests and radiation surveys) are made within the reactor room, environmental surveying generally pertains to the buffer zone and the further regions beyond the laboratory boundary.

Area Wipe Tests for Contamination s

Weekly routine surveys for removable radioactive material from selected areas both inside and outside the controlled regions in areas having the greatest potential for contamination were performed. Results indicated that no discernible radioactive material cross-contamination was identified outside of the. controlled areas.

REACTOR SHIELD SURVEY A complete area radiation survey (beta, gamma, and neutron) was .

conducted during a steady-state, full power operation on June 29th.

This survey was taken with the normal biological radiation shielding in place. The biological shields have not been altered since the previous annual area survey. The survey was conducted by the campus Radiation Safety Officer assisted by the Reactor Supervisor. All results during full power operation were completely negligible. On top of the reactor, measurable gamma-ray levels were found that justified the continued use of radiation area signs. The only neutron signal was observed next to w the thermal column. No significant radiation levels were found.

The survey report was subsequently misplaced or misfiled and is 9

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now assumed to be lost. The preceding recollections are excerpted in

. part from correspondence to the NRC regarding the loss.

Area Film Badge An environmental area film badge program is currently conducted in and around the NEL. In Calendar Year 1982 this program consisted of 27 film badges divided into one month and three month integrating periods and are located at strategic locations (see Table III) inside and outside of Boelter Hall, the Math Science Addition, and the NEL. There

' are two badges (which may be described as source badges) located inside 6

the exhaust stack: one at the exhaust fan; and the other at the center of the exhaust exit. The location and issue schedule of the badges are described in Table III.

The films are :(odak Type 2 double emulsion, personal monitor film in filtered standard metal holders which are the same as those used in personnel beta-gama monitoring.

The threshold detection levels for these films are:

X-ray (<l50 kev) 10 mR

. gamma (>l50 key) 20 mR i beta 20 mrad The film exposure is cumulative and a three month integration time will detect lower exposure rates (factor of three) than a one month integration time. The films are processed and read by UCLA's Radiation l

Safety Office.

Five of the badges were placed in offices or rooms of the MSA at the request of their occupants. Those badges are not part of any 13

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a TABLE III LOCATION AND IDENTIFICATION OF BETA GAMMA AREA FILM BADGES FILM BADGE ISSUE FILM BADGE AREA FILM BADGE LOCATIONS LOCATION PERIOD NUMBER A. MATH SCIENCE ADDITION MSA RM B331 INSIDE AIRSMAFT S-11 3 M0.

? 2372 HSA RM 7331 INSIDE AIRSHAFT S-10 3 MO.

1 2357 MSA RM 6331 INSIDE AIRSHAFT S-9 3 M0 2367 MSA RM 5329 INSIDE AIRSHAFT S-8 3 MO.

6 2349 MSA RM $907 MR. W. KEHL'S OFFICE (INNER) 3 M0.

3202 MSA RM 5308 MR. W. DRAIN'S OFFICE (0 UTER) 3 M0.

2312 MSA RM 4302B MR. M. STEPHEN'S OFFICE 3 M0.

2298 (INNER)

MSA RM 4328C COMPUTER AIR SUPPLY SHAFT 3 MO.

2287 MSA RM 4328D INSIDE AIRSHAFT S-6 3 M0.

2374 MSA RM 3940 INSIDE AIRSHIPT S-4 3 M0.

2395 MSA RM 3901 MR. ARCHER'S OFFICE 3 MO.

2268 MSA RM 2334 KEYPUNCH ROOM WINDOW 3 MO.

2378 MSA RM 2334 KEYPUNCH ROOM VENT INTAKE 3 M0.

0834 B. NUCLEAR ENERGY LABORATORY INCLUDING TOKAMAK RESEARCH AREA BH RM 2001 REACTOR CONTROL ROOM EAST WINDOW 3 MO.

0218 0219 BH RM 1005 SAMPLE REFINING AND CONC. LAB 3 MO.

BH RM 2567 NEL BUSINESS OFFICE BADGE RACK 3 MO.

0220 BH RM 1561 SHOP SOUTH OF R.H.B. 3 MO.

0230 MSA RM 2000A HEALTH PHYSICIST'S OFFICE 1 MO.

1581 MSA RM 2000 NEL CLASSROOM 3 MO.

1914 BH RM 1000A EAST WALL TAKAMAr LAB ** 1 MO.

. 1944 BH RM 1000A WEST WALL TOKAMAK LAB ** 1 M0.

1951 MSA RM 10008 EAST END HEAT TRANSFER LAB ** 3 M0.

1965 MSA RM 1000B CENTER OF HEAT TRANSFER LAB 3 MO.

2048

} 1 MO.

0203 BH RM 8000 INSIDE EXHAUST D0GHOUSE EXHAUST STACK EXIT GRILLE 1 M0.

0265 BH RM 8000 MATH SCIENCE INTAKE DUCT 1 MO.

0302 BH RM 9000 SOUTH OF REGION 1 TOWARD 8500 BH 1 M0.

CS20 BH RM 8000 I

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official program; they are at locations requested by the occupants. All

. badges so placed showt-d no measurable radiation. These results are consistent with those from prior years.

The results of the 1982 area film badg'e program are shown in Table IV. Area badges in the MSA were placed in airshafts or intake ducts in locations generally inaccessible to the public, but chosen to monitor the air supply. Badges so placed in years past have shown no detectable radiation.

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Section 7 Personnel Dosimetry The personnel dosimetry program is administered by the UCLA Radiation Safety Office. Film badges for beta-gamma exposure and i

thermoluminescent dosimeters, for fast neutrons as appropriate, were issued to personnel who were occupationally exposed to ionizing radiation. Nineteen faculty and staff members in the NEL and ten students enrolled in ENG 135A were included in the personnel dosimetry program. A review of the supporting records for the dosimetry program a

6 indicated that whole body occupational exposures were in conformance with the applicable limits of Title 10, Code of Federal Regulations, Part 20.

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TABLE IV QUARTERLY AREA FILM BADGE EXPOSURES - 1982 F Badge 1st Quarter 2nd Quarter 3rd Quarter 4th Quarter 2372 0 0 0 0 2357 0 0 0 0 2367 0 0 0 0 2349 0 0 0 0 3202 0 0 0 0 e 2312 0 0 0 0

} .

2298 2287 0

0 0

0 0

0 0

0 e 2374 0 0 0 0 239b 0 0 0 0 2268 0 0 0 0 2378 0 0 0 0 0834 0 0 0 0 s 0218 0 0 0 0 0219 0 0 0 0 0220 0 0 0 0 0230 0 0 0 0 1581 0 0 0 0 1914 0 0 0 0 1944 85* 20* 70* 35*

1951 55* 95* 460* 95*

1965 0 0 80* 0

• 0 80* 0 2048 0 g

, 0203** O O O O

' 0265** 408 0 0 0 0302 0 0 0 0 0820 0 0 0 0

• These films reflect Tokamak operation

• • These films showed no gamma radiation responses as they are located in the reactor exhaust stack main airstream before dispersion. These values are beta responses, p .

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UNIVERSITY OF CALIFORNIA, LOS ANGELES j, UCLA

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• BEREELEY

• I)ol$

• IRVINE

• IA)S ANGELES RIV ER$1DE $4N DREGO * $4N FR4NCISCO o 5ANTA BARBAR4 * $ANTA CRUZ

'6 COMMUNTIY SAFETY DEPARTMENT OFFICE OF RESEARCH ar OCCUPATIONAL SAFETY IDS ANGELES, CALIFORNIA 90094 22 June 1983 Mr. Hal Bernard, Acting Chief Standardization and Special Projects Branch Division of Licensing USNRC Washington, D.C. 20555 Docket 50-142 License R-71

Dear Mr. Bernard:

Enclosed are two copies of the UCLA Nuclear Energy Laboratory Annual Report for 1982, covering the period from January 1, 1982 through December 31, 1982. Two copies have also been sent to the Director of Region V. ,

Sincerely,-

b ut c.Os L L h Walter F. Wegst, Director Office of Research & Occupational Safety WFW/jb enc.

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