ML20087H019

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Us Dept of Interior, Geological Survey (USGS) - Submittal of 2019 Annual Report
ML20087H019
Person / Time
Site: U.S. Geological Survey
Issue date: 03/02/2020
From: Farwell C
US Dept of Interior, Geological Survey (USGS)
To:
Document Control Desk, Office of Nuclear Reactor Regulation
References
Download: ML20087H019 (6)
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  • us s science for a changing world Department of the Interior US Geological Survey Box 25046 MS-974 DenverC0,80225 March 2, 2020 U.S. Nuclear Regulatory Commission Document Control Desk Washington DC 20555

Dear NRC staff,

Enclosed is the 2019 annual report for the U.S. Geological Survey TRIGA non-power reactor facility.

The facility docket number is 50-274.

Sincerely, 3/2/2020 X

Christopher Farwell Actinq Reactor Supervisor Siqned by: CHRISTOPHER FARWELL Enclosure Copy to:

Geoffrey Wertz OWFN 12 D20

U.S. GEOLOGICAL SURVEY TRIGA REACTOR ANNUAL REPORT JANUARY 1, 2019 - DECEMBER 31, 2019 NRC LICENSE No. R-113 DOCKET NO. 50-274 I. Personnel Changes:

Brycen Roy resigned from the facility effective 7/15/2019. Christopher Farwell remains the acting Reactor Supervisor.

II. Operating Experience The Geological Survey TRIGA Reactor (GSTR) remains in an administratively- limited state of operations until staffing levels can be restored. A synopsis of irradiations performed during the year is given below, listed by the organization submitting the samples to the reactor staff:

Organization Number of Samples USGS- INAA 64 USGS - Geochronology 0 USGS-other 0 Non-USGS 0 Total 64 A. A thermal power calibration was performed in November, with adjustments made to the instrumentation as required.

B. During the report period, 67 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 131.

1

Ill. Tabulation of Energy Generated MWh operated Critical hours Pulses Jan 00.000 ooh oom 0 Feb 00.000 ooh oom 0 Mar 00.000 04h 07m 0 Apr 00.000 ooh oom 0 May 00.000 ooh oom 0 June 00.000 04h 56m 0 July 00.000 ooh oom 0 Aug 00.000 ooh oom 0 Sept 00.000 07h 19m 0 Oct 3.272 09h 59m 0 Nov 5.999 12h 26m 10 Dec 2.560 09h 16m 1 Totals 11.831 48h 03m 11 IV. Unscheduled Shutdowns One (1) unscheduled shutdowns occurred in 2019. These were:

Number , Date Cause 1144 11/4/2019 NPP Percent High SCRAM; all detectors were operating stably around 750 kW before suddenly SCRAMing and showed no trend of increasing towards the SCRAM setpoint.

History traces confirm that a valid actuation of the SCRAM with the reactor exceeding the power setpoint is very unlikely. Thus, this SCRAM is believed to be spurious and not indicative of an actual reactor power in excess of the setpoint.

V. Significant Maintenance Operations

  • 2/12/2019 Replaced resin in IX Tank in Reactor Bay and in Rm 151. No leaks detected.
  • On 3/28/2019 the discriminator-R304 on the NM was adjusted to correct the indicated power with the source in the core when the reactor was shut down. It was corrected from a power of 15mW to 18mW. An ops test was performed, the results were satisfactory.
  • On 6/13/2019 NP1000 potentiometer R23 was adjusted with an input current to bring the NP1000 reading into agreen,ent with the input source.
  • On 6/20/2019 the discriminator-R304 on the NM was adjusted to correct the indicated power with the source in the core when the reactor was shut down. It was corrected from a power of 14m~ to 18mW. An operational test was performed, the results were satisfactory ..
  • On 7/31/2019 the potentiomet~r for mode 5 was adjusted to bring indicated a calibrated input within the correct range.

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  • On 10/29/2019 the NP and NPP R29 potentiometer was adjusted. This potentiometer is connected to the scram set point. The ROC instructed the facility to adjust the scram setpoints from 110% power to the administrative power restriction of 880kW. The operational test was performed by injecting a current into the detector circuitry and was satisfactory for both detectors.
  • 10/31/2019 Performed annual ~urveillance on TR Drive IAW Procedure 28. Appearance and function OK; lubrication adequate; drop time 0.584 s.

VI. Summary of 10 CFR 50.59 changes No 50.59 changes were made to the facility in CY 2019.

VII. Radioactivity Releases A. Listed below are the total amounts of radioactive gaseous effluents released to the environment beyond the effective control of the reactor facility Table 1. Gaseous Effluents Released to the Environment in CY 2019 -

Month Argon-41 R-113 License Tritium -HTO 10CFR20 Allowable (mCi)

  • Allowable (Ci) (Ci) (mCi)

January 0.000 5.833 0.000 124 February 0.000 5.833 0.115 124 March 0.000 5.833 0.000 124 April 0.000 5.833 0.102 124 May 0.000 5.833 0.000 124 June 0.000 5.833 0.068 124 July 0.000 5.833 0.000 124 August 0.000 5.833 0.059 124 September 0.000 5.833 0.000 124 October 0.056 5.833 0.106 124 November 0.873 5.833 0.000 124 December 0.022 5.833 0.064 124 Total 0.951 70.000 0.515 1488

% of Allowable 0.01 % ------------------- 0.035% -------------------

  • 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 ALS Laboratories.

B. No liquid releases were made during the 2019 calendar year.

VIII. Radiation Monitoring 3

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

1. Ten (10) gamma-sensitive area monitors, and one (1) neutron-sensitive area monitor, 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 infreqvent and due to sample movements. These monitors are calibration-checked annually.
2. One Continuous Air Monitor (CAM) samples air in the reactor bay. An equilibrium concentration of about 1.5 x 10-s µCi/ml present for two minutes will result in an_ increase of about 500 cpm above background. Two alarm setpoints are a low-level alarm set at 5,000 cpm and a high level alarm set at 10,000 cpm. Reactor bay air is sampled during all reactor operations. The fixed particulate air filter is normally changed each week and counted on a HPGE gamma spectrometer. The charcoal filter, positioned behind the particulate air filter, is also normally changed and counted weekly. Filter data showed radioisotope concentrations less than allowable airborne concentration limits given in 10 CFR Part 20, Appendix B, Table 2 for all particulate radioisotopes produced by the reactor.
3. Contamination wipe surveys and portable instrument radiation surveys are pe'rformed at least once a month. The portable instruments are calibrated with a 3-Curie (initial activity) Cs-137 source traceable to NBS, and wipes are counted on a Gamma Products G5000W low-level counting system. The highest removable contamination found was during the November surveys, at 218 pCi/100 cm 2 beta-gamma, located in the reactor bay at the rear table. This contamination likely occurred as a result of removing activated sample containers from the core. No other beta-gamma contamination above 61.4 pCi/100 cm 2 was detected. No areas were greater than 9.3 pCi/100 cm 2 alpha contamination, which does not require decontamination as it is well below the limit of 90 pCi/100 cm 2 alpha. 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. TLD dosimeters were used at seven outdoor environmental stations. Reactor facility visitors are issued self-reading electronic dosimeters. Reactor staff personnel are issued beta, gamma, albedo neutron badges. (NOTE: Neutron exposure was less than the minimum reportable doses for the badges throughout this time frame)

Table 3. Personnel Monitoring Results (12/1/18...:. 11/30/19)

Employee Whole Body (Rem) Whole Body (Rem)

Extremity (Rem) code Deep Dose Equiv. Shallow Dose Equiv.

E0707 0.000 0.000 0.000 E0908 0.013 0.039 0.147 E0715 0.004. 0.033 0.023 Reactor visitors and visiting experimenters wore electronic pocket dosimeters which showed that no individual's reading greater than 3.0 mRem in a single visit or as a cumulative annual dose.

4

Table 4. Environmental Dose Results (Oct 2018 through Sept 2019)

Total !

Dose Dose Dose Dose Location Oct.- Dec. (REM) Jan-Mar (REM) Apr-June (REM) July-Sept. (REM)

(REM)

Control (Background) 0.062 0.063 0.053 0.050 0.228 Main Exhaust 0.015 0.011 0.028 0.000 0.054 West Vehicle Gate 0.012 0.016 0.000 0.000 0.028 West Room 151 Gate 0.033 0.031 0.039 0.014 0.117 Cooling Tower 0.000 0.012 0.000 0.000 0.012 SE Light Pole 0.000 0.000 0.000 0.000 0.000 SW Light Pole 0.000 0.000 0.000 0.000 0.000 Rx Fence Loading Dock 0.023 0.024 0.012 0.017 0.076 Tunnel 0.029 0.033 0.034 0.017 0.113

  • Note: Above totals have the background subtracted (see control badge). All TLDs were supplied and analyzed by Mirian Technologies.

IX. Environmental Monitoring Biennial soil samples are due to be collected in summer 2020.

X. Fuel Inspection results No fuel inspections occurred in CY19 5

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