ML080250023

U.S. Geological Survey Trigra Reactor Annual Report for 2007

ML080250023
Person / Time
Site:	U.S. Geological Survey
Issue date:	01/18/2008
From:	Timothy Debey US Dept of Interior, Geological Survey (USGS)
To:	Document Control Desk, Office of Nuclear Reactor Regulation
References
Download: ML080250023 (6)

Text

ZUSGS science for a changing world Department of the Interior US Geological Survey Box 25046 MS-974 Denver CO, 80225 January 18, 2008 U.S. Nuclear Regulatory Commission Document Control Desk Washington DC 20555

Dear NRC staff:

The attached annual report of the U.S. Geological Survey TRIGA non-power reactor facility is submitted in accordance with license conditions.

The facility docket number is 50-274.

Sincerely, Reactor Supervisor Enclosure Copy to:

Al Adams, MS 12 G-13

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U.S. GEOLOGICAL SURVEY TRIGA REACTOR ANNUAL REPORT JANUARY 1, 2007 - DECEMBER 31, 2007 NRC LICENSE NO. R-1 13 - DOCKET NO. 50-274 I.

Personnel Changes:

Paul Lietz resigned from his position at the facility, effective June 7, 2007.

Paul Lietz's operator license was terminated as a result of his resignation.

Alex Buehrle was hired as a student employee and began working on June 11, 2007.

Brycen Roy was hired as a student employee and began working on July 23, 2007.

II.

Operating Experience The Geological Survey TRIGA Reactor (GSTR) was in normal operation for the year 2007. No major facility changes were made during the year. A nuclear engineering laboratory course was held at the facility as part of the curriculum of the Colorado School of Mines. This course is expected to be provided on an annual basis.

A synopsis of irradiations performed during the year is given below, listed by the organization submitting the samples to the reactor staff:

Organization Geologic Discipline - INAA Geologic Discipline - Geochronology Non-USGS Total Number of Samples 1044 1158 1452 3654 A. Thermal power calibrations were performed in January and July, with no adjustments made to the instrumentation.

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B. During the report period, 182 daily checklists and 12 monthly checklists were completed in compliance with technical specifications requirements for surveillance of the reactor facility.

C. Tours were provided to individuals and groups during the year for a total visitor count of approximately 350.

III.

Tabulation of Enerav Generated Jan Feb Mar Apr May June July Aug Sept Oct Nov Dec Totals MWH operated 63.705 58.217 50.394 61.249 67.983 24.793 43.413 81.475 70.600 77.341 35.900 10.212 645.282 Critical hours 80h 20m 59h 45m 54h 24m 61h 19m 69h 51m 29h Olm 55h 58m 85h Olm 72h 15m 80h 16m 37h 47m 11h 41m 697h 38m Pulses 0

0 0

0 0

0 5

0 0

0 0

0 5

IV.

Unscheduled Shutdowns Number 1022 1023 1024 1025 1026 1027 1028 1029 Date 03115/07 03/23/07 06/26/07 07/20/07 08/27/07 09/04/07 09/04/07 12/07/07 Cause DAC DIS064 timeout DAC DIS064 timeout DAC DIS064 timeout DAC DIS064 timeout NPI 000 hi power while going to full power NP1000 hi power due to noise spike NP1000 hi power; bad HV connector DAC DIS064 timeout V.

Significant Maintenance Operations

1. The ion exchange resin and filters were replaced in January.

2. The lithium battery in the NM1000 microprocessor was replaced in January.

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3. Fittings at the conductivity meter probes were leaking; replaced in January.

4. The Tektronix hi-resolution console monitor was replaced in April.

5. The ion exchange resin and filters were replaced in May.

6. Lead shielding was added around the demineralizer tank in June.

7. A 10 kQ resistor in the NP1000 was replaced in July.

8. The primary pump motor/pump shaft was aligned in August.

9. The signal lead on the NP1000 was rebuilt in August.

10. A dry tube in a reflector-mounted position had a water leak. The tube was drained, inverted and reinstalled in October.

11. The console ACKNOWLEDGE switch was replaced in December.

12. During routine rod inspection testing of SHIM1 drive in December, it was discovered that the dashpot piston assembly had become disconnected.

Holes were re-tapped, new screws were installed and the drive was returned to service.

Vl.

Summary of 10 CFR 50.59 changes No 50.59 changes were made during this year.

VII.

Radioactivity Releases A. Listed below are the total amounts of radioactive gaseous effluent released to the environment beyond the effective control of the reactor facility.

Table 1. Gaseous Effluents Released to the Environment Month Argon-41 License Tritium (HTO)

IOCFR20 Allowable Allowable (curies)

(Ci)

(R-113)

(mCi)

(mCi)

January 0.338 5.833 0.044 124 February 0.459 5.833 0.080 124 March 0.174 5.833 0.0 124 April 0.635 5.833 0.0105 124 May 0.463 5.833 0.058 124 June 0.399 5.833 0.047 124 July 0.255 5.833 0.0 124 August 0.655 5.833 0.071 124 September 0.244 5.833 0.0 124 October 0.637 5.833 0.077 124 November 0.320 5.833 0.0 124 December 0.088 5.833 0.088 124 Total 4.67 70.00 0.570 1488

% of Allowable 6.67%

0.04%

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• Note:

The tritium concentrations are estimates based on the amount of water lost by evaporation from the reactor multiplied by the concentration of tritium as HTO. Tritium sample analyses were performed by Severn Trent Laboratories.

B. One solid, low-level waste shipment of 7.5 cu. ft. was made this calendar year.

VIII.

Radiation Monitoring Our program to monitor and control radiation exposures included the four major elements below during the operating year.

1. Fifteen gamma-sensitive area monitors are located throughout the Nuclear Science Building. A remote readout panel is located in the reactor health physics office. High alarm set points range from 2 mR/hr to 50 mR/hr. High level alarms are very infrequent and due to sample movements.

2. One Continuous Air Monitor (CAM) provides sampling of the air in the reactor bay. An equilibrium concentration of about 1 x 10`8 gCi/ml present for two minutes will result in an increase of 400 cpm above background. There are two alarm setpoints. A low-level alarm is set at 3000 cpm and the high level alarm is set at 10000 cpm. Reactor bay air is sampled during all reactor operations. The fixed particulate air filter is changed each week and counted on a HPGE gamma spectrometer counting system. The charcoal filter, fitted behind the air filter, is also changed and counted weekly. In all instances, sample data were less than airborne concentration values in 10 CFR Part 20, Appendix B, Table 2 for all particulate radioisotopes produced by the reactor.

3. Contamination wipe surveys and radiation surveys with portable survey instruments are performed at least once a month. All portable instruments are calibrated with a 3-Curie (initial activity) Cs-1 37 source traceable to NBS, and wipes are counted on a Gamma Products G5000 low level counting system. All areas were less than 30 pCi/1 00 cm 2 beta and 15 pCi/1 00 cr2 alpha contamination.

The roof area over the reactor tank is roped off and posted as a radiation area (averaging 2.5 mR/hr) during 1 MW operations.

4. LiF TLD dosimeters were used at four outdoor environmental stations. Reactor facility visitors are issued self-reading dosimeters. Reactor staff personnel are issued beta, gamma, albedo neutron badges.

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Table 2. Personnel Monitoring Results (111107 - 12/31/07)

Deep Dose Shallow Dose Equivalent Equivalent Name Whole Body (Rem)

Whole Body (Rem)

Extremity (Rem)

Buehrle, A 0.021 0.049 0.102 DeBey, T 0.121 0.220 0.236 Lightner, G 0.260 0.362 1.270 Liles, D 0.212 0.220 0.556 Roy, B 0.000 0.000 0.046 Reactor visitors and occasional experimenters wore pocket dosimeters that resulted in no individual reading that was greater than one (1) mrem.

Table 3. Environmental Dose Results Location Dose Dose Dose Dose Total Jan-Mar Apr-June July-Sept Oct-Dec (RAD)

(RAD)

(RAD)

(RAD)

(RAD)

Exhaust 0.044 0.033 0.037 0.033 0.147 Stack Cooling 0.007 0.004 0.000 0.008 0.019 Tower Fence West Vehicle 0.017 0.012 0.019 0.020 0.068 Gate West Room 0.067 0.046 0.022 0.023 0.158 151 Gate Southwest 0.008 0.001 0.008 0.010 0.027 Light Pole Control 0.036 0.032 0.038 0.041 0.147 (background)

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Southeast 0.001 0.002 0.000 0.001 0.004 Light Pole I

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I Note: Above totals have the background subtracted (see control). Environmental TLDs were supplied and analyzed by Global Dosimetry Solutions.

X. Environmental Monitoring There have been no uncontrolled radioactivity releases from the reactor to the present date. Thus, the data on file from past years to the present are considered to be background information.

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