ML042530065

University of Arizona Annual Report

ML042530065
Person / Time
Site:	05000113
Issue date:	08/24/2004
From:	Williams J Univ of Arizona
To:	Document Control Desk, Office of Nuclear Reactor Regulation
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Download: ML042530065 (6)

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Nuclear Reactor Laboratory Engineering Building (20)

P. 0. Box 210020 Tucson, Arizona 85721-0020 THE UNIVERSr OF ARIZONA IIUCSON ARIZONA John G. Williams, Director e-mail: jgwvengr.arizona.edu voice: (520) 621-9729 FAX: (520) 621-8096 August 24, 2004 U. S. Nuclear Regulatory Commission Document Control Desk Washington, DC 20555 RE: Annual Report for License R-52, Docket 50-113 This is the Annual Report covering the period July 1, 2003, through June 30, 2004, for the activities of the TRIGA Mark I Reactor at the University of Arizona, Tucson, Arizona. The report is submitted in compliance with Section 6.7e of the Facility Technical Specifications and Paragraph 50.59(b) of Title 10, Code of Federal Regulations.

1.

During the reporting period, the reactor was operated for research and education. It was used for reactor operator training of operators at this facility. The reactor was used for graduate thesis research. The reactor was also used for neutron activation analysis for teaching and research.

There were no reactor upgrading or modifications during the reporting period.

Power channel calibration by the calorimetric method was performed during the reporting period. The total worth of the regulating, shim, and transient rods were measured to be $3.99, $3.17, and $2.42, respectively. The largest change in worth was 1.60% of total worth on the Transient rod, which is consistent with the small changes in rod worth due to rotational changes of position of individual fuel elements from fuel movement during approach to critical experiments and fuel inspection.

Ten pulses or reactivity insertions greater than $1.00 were performed since the previous fuel measurement.

Maximum reactivity insertion rates of $0.17/sec, $0.1 1/sec, and $0.16/sec were measured for the regulating, shim, and transient rods, respectively. All three insertion rates were less than the maximum rate allowed by the facility technical specifications.

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The transient rod drive assembly was inspected twice during the reporting period. Both piston seals were found to be in satisfactory condition and no wear or rust accumulation was present in the air cylinder.

Rod drop times from full out to full insertion were measured to be 0.38, 0.38, and 0.75 seconds for the regulating, shim, and transient rods, respectively.

There was no appreciable change in the drop times of the control rods since the last rod drop measurements. All three drop times were less than the time required by the facility technical specifications. The regulating, shim and transient rods were visually inspected during the reporting period. All three control rods passed visual inspection.

The area radiation monitors, the pool activity monitor and the pool conductivity meter were calibrated during the reporting period.

2.

The reactor was critical for a total of 42 hours4.861111e-4 days <br />0.0117 hours <br />6.944444e-5 weeks <br />1.5981e-5 months <br />, producing 596.5 kW-hours (0.025 MW-day) of thermal energy. The cumulative energy output since the facility was commissioned is 9.838 MW-days. During the reporting period 10 pulses with input reactivity greater than $1.00 were performed. The cumulative number of pulses greater than $1.00 since the time pulsing was initiated is 2225.

The reactor was in operation 59 days during the reporting period, with 53 hours6.134259e-4 days <br />0.0147 hours <br />8.763227e-5 weeks <br />2.01665e-5 months <br /> of operating time, as recorded by the console clock.

3.

There was no inadvertent reactor scram during the reporting period.

4.

Major maintenance included repair of the circuit card for the Log Channel's Discriminator and Driver. The circuit failed causing the Rod Withdrawal Prohibit (RWP) light to illuminate. The problem was found to be a faulty transistor which was replaced. Minor maintenance items included servicing the C.A.M. air pump, adding pool water lost by evaporation, replacing burned out light bulbs in the reactor pool, replacing burned out annunciator bulbs in the reactor control console, changing batteries in the low water level detector circuit and area monitors, and making periodic adjustments to the reactor control console circuitry.

5.

The Reactor Committee met four times during the reporting period: 8/21/03, 12/11/03, 3/8/04, and 5/3/04.

At its meetings and in individual reviews by Committee members, the Committee reviewed operations and operational records of the facility as specified by the Committee charter. This included audit of preliminary check sheets, pulsing check sheets, approach to critical and termination check sheets, operations and 2

maintenance log books, monthly and annual check sheets, irradiation records, and experiments performed with the reactor. The Committee reviewed the 2003 annual report to the NRC.

The Reactor Committee reviewed no 10CFR50.59 safety evaluations during the reporting period. However, the reactor committee did review several procedural and Physical Security Plan changes.

6.

No liquid or solid waste was discharged from the facility during the reporting period.

Measurements of the Argon41 concentration in the reactor pool water have demonstrated that the maximum rate of release of Argon-41 from reactor pool water is less than 0.74 yCi per kilowatt-hr of reactor operation. The pneumatic transfer system produces approximately 0.05 pCi of Argon-41 per kW-min of reactor operation, some of which is released when the system is operated.

Presented below are the calculations of the maximum monthly releases of Argon-41 from the reactor pool surface, the pneumatic transfer system and the totals.

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Argon-41 (uCi)

Pneumatic Argon-41 (CCi)

Argon-41 (JLCi)

Transfer Total Month Pool Surface System July 2003 11.91 0.0 11.91 August 2003 12.28 0.0 12.28 September 2003 114.6 0.0 114.6 October 2003 14.58 0.0 14.58 November 2003 62.16 0.0 62.16 December 2003 56.24 0.0 56.24 January 2004 46.92 0.0 46.92 February 2004 2.96 0.0 2.96 March 2004 7.25 0.0 7.25 April 2004 45.88 0.0 45.88 May 2004 0.0 0.0 0.0 June 2004 66.6 0.0 66.6 The daily calculations for Argon-41 release from the pneumatic transfer system did not include decay of the isotope prior to release and, therefore, give an over-estimate of Argon-41 release. The maximum total estimated Argon-41 release from the facility during the reporting period is 0.44 millicuries. There were no other gaseous effluents from the facility during the reporting period.

7.

Six (6) persons were issued film badges on a monthly basis for all or part of the reporting period in the Nuclear Reactor Laboratory. The persons receiving badges included all reactor operators, faculty and staff members using the reactor laboratory, researchers, and all students in laboratory courses. No badged individuals were reported as having received exposures above background.

Sixty-six (66) non-badged persons were admitted to the Reactor Laboratory in classes, tours, or on official business during the reporting period. All groups were issued pocket dosimeters. Pocket dosimeters issued to visitors indicated that no exposure was received.

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8.

Radiation surveys of the reactor room, control room, and experiment set-up room were conducted monthly during the reporting period by members of the University of Arizona Radiation Control Office(RCO) using direct measurement and wipe tests. The results show little detectable activity except where expected (i.e.,

irradiated samples in storage areas and internal wall surfaces of the irradiation facilities). Other radiation surveys were performed by members of the reactor laboratory staff when necessary. No radiation exposure which can be attributed to reactor operations has been detected outside the reactor laboratory.

9.

Environmnental TLD monitors at 3 locations on the roof of the building housing the reactor and at 10 other roof locations on the University campus were replaced and read quarterly during the reporting period. For the 12 month period from July 1, 2003 through June 30, 2004 the total doserates, after subtraction of the average background reading for 11 of 13 TLDs were 0 mR/yr. One TLD in the Arizona Health Sciences Center and one TLD in the Art building read 5.6 mR/yr and 39.6 mR/yr respectively. These higher readings are attributed to building materials as reported by the Radiation Control Office. There is no evidence that radiation exposures in the vicinity of the reactor are higher than normal. Eight TLD monitors were placed at the periphery of the restricted area, and two TLD monitors were placed in an office area far removed from the restricted area to provide a baseline reference for building background. The TLDs on the periphery of the NRL ranged from 20 mR/yr to 108 mR/yr. The areas where monitor readings exceeded 100 mR/yr were surveyed using a calibrated ion chamber quarterly by the Radiation Control Office with the reactor operating at 100 kW. No radiation fields were detected that exceeded background levels (0.01 mR/hr).

To meet the requirements of 10CFR20.1302, the sum of internal and external radiation dose to the public must not exceed 100 mrem/yr or 2.0 mR/hr. As stated above, with the reactor operating at 100 kW, no instrument reading exceeded 0.01 mR/hr. To estimate the radiation dose from internal and external radiation sources, the highest environmental monitor reading is summed with the Ar-41 estimated dose and multiplied by an occupancy factor of 0.25 (very conservative). The highest dose was 119 mR/yr and Comply Code estimated dose (0.2 mR/yr) are summed and multiplied by the occupancy factor (0.25) to estimate dose to the public of 28.6 mR/yr.

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In writing this report, I have tried to be both complete and as brief as is reasonable, and still satisfy the requirements of 10CFR50.59, the Facility Technical Specifications, and the needs of the Commission. If other or more detailed information is needed, please contact me at your earliest convenience.

Sincerely, John G. Williams, Director Nuclear Reactor Laboratory JGW:MG cc:

Events Assessment, Generic Communications and Non-Power Reactors Branch Division of Regulatory Improvement Programs Office of Nuclear Reactor Regulation One White Flint North 11555 Rockville Pike Rockville, MD 20852-2738 Mr. Marvin Mendonca Project Manager USNRC Dr. Richard Powell Vice President for Research University of Arizona Dr. Michael Cusanovich Director ARL University of Arizona C:\\NRL\\Reports\\anrptO4.doc 6