ML071910231

the University of Utah Triga Reactor, Annual Operating Report for the Period 1 July 2006 Through 30 June 2007

ML071910231
Person / Time
Site:	University of Utah
Issue date:	07/02/2007
From:	Krahenbuhl M Univ of Utah
To:	Document Control Desk, Office of Nuclear Reactor Regulation
References
Download: ML071910231 (8)

Text

Center for Excellence in Nuclear Technology, Engineering,and Research 2 July 2007 U.S. Nuclear Regulatory Commission Document Control Desk Washington, D.C. 20555 To whom it may concern:

Enclosed is the annual operating report for the University of Utah TRIGA Nuclear Reactor, License No. R-126, Docket number 50-407, for the period of 1 July 2006 through 30 June 2007.

This report fulfills the requirements of the TRIGA technical specifications (TTS) 6.10(5).

If there are any further questions or concerns regarding this report, please contact me at (801) 581-4188 Respectfully, Reactor Administrator 40)20

The University of Utah TRIGA Reactor Annual Operating Report for the period 1 July 2006 through 30 June 2007 A. NARRATIVE

1. Operating Experience The University of Utah Center for Excellence in Nuclear Technology, Engineering, and Research (CENTER) TRIGA Reactor, License No. R- 126, Docket No. 50-407, was critical 52.463 hours0.00536 days <br />0.129 hours <br />7.655423e-4 weeks <br />1.761715e-4 months <br /> and generated 1289.236 kilowatt-hours of thermal energy during this reporting year. The reactor was used for educational demonstrations, laboratory experiments, systems tests, power measurements and sample irradiations.

2. Changes in Facility Design The documents supporting a forthcoming upgrade in licensed power from 100 kW to 250 kW are being reviewed by the NRC. No facilities changes have occurred.

3. Surveillance Tests Documentation of all surveillance activities is retained and stored by the facility.

a. Control Rod Worth Table 1.

Summary of control rod worth, SDM, and ER Core Configuration #24-B #24-B #24-B Date 8/25/06 11/08/06 2/22/07 Worth ($) Worth ($) Worth ($)

Safety Rod 2.017 2.120 2.173 Shim Rod 1.463 1.503 1.547 Regulating Rod 0.270 0.263 0.273 Excess Reactivity 0.751 0.771 0.787 Shutdown Margin 0.983 0.996 1.033

b. Control Rod Inspection The Biennial Control Rod Inspection was performed during December 2005.

The control rods were sequentially removed from the reactor core for visual inspection. Each control rod was found to be in good condition with no noticeable deterioration or corrosion having occurred since the last inspection.

Rod drop times were measured on 8/25/06, 11/08/06, and 2/22/07. All rod drop times were less than 1.0 seconds.

c. Reactor Power Level Instrumentation Calorimetric power calibrations were performed on 8/29/06, and 2/23/07 with the following results:

Date Measured % Power Calculated Power Level 8/29/06 91.8 86.7 2/23/07 92.0 91.9

d. Fuel Inspection The Biennial Fuel Inspection was performed during December 2005. Each fuel element was visually inspected while keeping it submerged for shielding.

No deterioration or excessive corrosion of in-core fuel elements was observed since the previous inspection. Pool water is sampled and analyzed periodically for evidence of fission product activity indicative of defective or deteriorating fuel. Analyses of pool water following full-power reactor operations lasting several hours have not shown any indication of fission product leakage.

e. Fuel Temperature Calibration Fuel temperature circuits were calibrated on 8/24/06 and 2/28/07. The circuits were calibrated to less than a 2°C error over the range 20'C to 400'C.

f. Reactor Safety Committee Audits Four Audits were completed during this period.

Table 2.

Audit Summary Audit Period auditor Operation and 1 Jan. 2006 to 30 Jun. 2006 David M. Slaughter Maintenance Radiation Safety and 1 Jan. 2006 to 30 Jun. 2006 David M. Slaughter ALARA Operation and 1 Jul. 2006 to 31 Dec. 2006 David M. Slaughter Maintenance Radiation Safety and 1 Jul. 2006 to 31 Dec. 2006 Rian B. Smith ALARA No significant deviations from normal operating practices were identified by these audits.

g. Environmental Surveys Six environmental monitors are located in areas surrounding the CENTER.

Rian B. Smith reported to the RSC a maximum exposure of 47 millirem per quarter to an environmental dosimeter located at building #80. Table 3 contains the average dose recorded for four prior years.

Table 3.

Summary of environmental monitoring Year Average quarterly readings for the 6 environmental monitors (mrem) 2006 36.74 2005 37.53 2004 35.58 2003 36.00 B. ENERGY OUTPUT The reactor was critical for 52.463 hours0.00536 days <br />0.129 hours <br />7.655423e-4 weeks <br />1.761715e-4 months <br /> and produced 0.054 megawatt-days (1289.236 kilowatt-hours) of energy during this reporting period. Since initial criticality, the reactor has been operated for a total of 3314.551 hours0.00638 days <br />0.153 hours <br />9.11045e-4 weeks <br />2.096555e-4 months <br /> with an accumulated total energy output of 8.434 megawatt-days (202410.162 kilowatt-hours).

C. EMERGENCY SHUTDOWNS AND INADVERTENT SCRAMS:

Table 4.

Summary of Inadvertent SCRAMS Date Run Type Cause Action Number 7/07/06 1527 Linear High voltage power interrupt N/A Power 9/21/06 1536 Linear High voltage power interrupt N/A Power 10/27/06 1546 Linear Feedback from the reactor power N/A Power switch 11/10/06 1552 Linear Feedback from the reactor power N/A Power switch 12/01/06 1564 Linear Feedback from the reactor power N/A Power switch 4/04/07 1576 Linear Feedback from the reactor power N/A Power switch There were 6 inadvertent SCRAMs occurred during this period (during NRC SRO training sessions). There were no emergency shutdowns. Summary of the inadvertent scrams are in Table 4.

D. MAJOR MAINTENANCE

1) New flow meter was installed.

2) PI (Pneumatic Irradiator) was re-installed

3) Concrete cap on the top of the reactor tank was removed and two 0.75" rubber mats were installed.

E. CHANGES, TESTS AND EXPERIMENTS PURSUANT TO 10 CFR 50.59 As of the end of the reporting period, the current membership of the Reactor Safety Committee (RSC) as designated by the Licensee is as follows:

James M. Byrne, Chair David M. Slaughter Karen Langely, RSO of University of Utah Melinda P. Krahenbuhl, Reactor Administrator Dongok Choe, Reactor Supervisor Gary M. Sandquist Robert J. Huber James Thompson Rian B. Smith The CENTER staff continues to review and update facility documentation to assure compliance with all applicable regulations.

F. RADIOACTIVE EFFLUENTS

1. Liquid Waste - Total Activity Released: none

2. Gaseous Waste - Total Estimated Activity Released: 14.338 ýtCi The TRIGA Reactor was operated for 52.463 hours0.00536 days <br />0.129 hours <br />7.655423e-4 weeks <br />1.761715e-4 months <br /> at power levels up to approximately 90 kW. At this power level argon-41 production is substantially below MPC values for unrestricted areas. The minimum detectable concentration of Ar-41 for the stack monitor has been found to be one-third of 10 CFR 20 appendix B limits for release to unrestricted areas.

The average annual calculated concentration of Ar-41 generated during operations is estimated at 6.835E-1 1ICi/ml approximately 0.002 % of the DAC for this radionuclide. The total amount of Ar-41 released was estimated at 14.338 *Ci. No phosphorus-32 was released from CENTER during this period. The total amount of all gaseous radioactivity released was estimated at 14.338 [Ci. A monthly summary of gaseous releases is given in Table 5.

Table 5.

1lmm rVV of Monthly Ga.*eons Radlioactive Effluent Month Ar-41 (;Ci) Estimated Release Total (ýtCi)

P-32 and all others July 0.397 0 0.397 August 3.028 0 3.028 September 0.949 0 0.949 October 1.382 0 1.382 November 4.194 0 4.194 December 0.518 0 0.518 January 0.129 0 0.129 February 3.412 0 3.412 March 0.330 0 0.330 April 0.000 0 0.000 May 0.000 0 0.000 June 0.000 0 0.000 Total Activity of gaseous effluent: 14.338 ýtCi

3. Solid Waste - Total Activity: None No solid waste material was sent to the Radiological Health Department for disposal during the period of 1 July 2006 through 30 June 2007.

G. RADIATION EXPOSURES Personnel with duties in the reactor laboratory on either a regular or occasional basis have been issued an OSL dosimeter by the University of Utah Radiological Health Department. The duty category and monitoring period of personnel are summarized in Table 6.

Table 6.

Summary of Monitored Personnel Name Monitoring Period Duty Category Jesse Reeves 7/01/06-6/30/07 Regular Melinda Krahenbuhl 7/01/06-6/30/07 Regular Dong-ok Choe 7/01/06-6/30/07 Regular Brian A. Harper 7/01/06-6/30/07 Regular Douglas Crawford 7/01/06-6/30/07 Regular John D. Bess 7/01/06-6/30/07 Regular Ward Chapman 7/01/06-6/30/07 Regular Jorge Navarro 7/01/06-6/30/07 Regular Christy Seiger Webster 7/01/06-21/31/06 Regular/Terminated Sang Kyu Lee 7/01/06-6/30/07 Regular/Terminated Roger Carrasquel 7/01/06-8/31/06 Regular/Terminated Nathan Brown 7/01/06-6/30/07 Regular Brandalyn Bassett 9/01/06-6/30/07 Regular Jeff Davis 11/01/06-6/30/07 Regular Michael A Summer 11/01/06-6/30/07 Regular/Terminated James A Gawenis 11/01/06-12/31/06 Regular/Terminated Margaret Fitch 4/01/07-6/30/07 Regular Jeniffer Davis 4/01/07-6/30/07 Regular Randall W Morrill 6/01/07-6/30/07 Regular David M Slaughter 12/01/06-6/30/07 Regular Measured Doses 7/1/06-6/30/07 Doses: <5 mrem average; 5 mrem highest measured Dose Equivalent Limit Maximum Permissible Dose Equivalent = 5000 mrem/year (1250/quarter).

Minimum Detectable Dose per Monthly Badge = 10 mrem.

Five hundred and nine (509) individuals visited the reactor facility during the period 1 July 2006 to 30 June 2007. None of the visitors received a measurable dose. A summary of whole body exposures to CENTER personnel is presented in Table 7.

Table 7.

Summary of Whole Body Exposures Estimated whole body exposure range Number of individuals in each range:

(rem):

No Measurable Dose 20 (Less than 0.10) 20 0.10 to 0.25 0 0.25 to 0.50 0 0.50 to 0.75 0 0.75 to 1.00 0 1.00 to 2.00 0 2.00 to 3.00 0 3.00 to 4.00 0 4.00 to 5.00 0 Greater than 5 rem 0 H. LABORATORY SURVEYS Monthly surveys of the facility were conducted by the University of Utah Radiological Health Department during the reporting period. The surveys have not indicated any unusual radiation levels over previous years. Records of surveys are retained by the facility.

I. ENVIRONMENTAL STUDIES Environmental monitoring conducted by the University of Utah Radiological Health Department indicated no unusual dose rates in the areas surrounding the Merrill Engineering Building, which houses the reactor facility.

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