ML110910064

From kanterella
Jump to navigation Jump to search
Annual Report: January 1, 2010 - December 31, 2010 for North Carolina State University
ML110910064
Person / Time
Site: North Carolina State University
Issue date: 03/30/2011
From: Hawari A
North Carolina State University
To:
Document Control Desk, Office of Nuclear Reactor Regulation
References
Download: ML110910064 (38)
v • d • e


Text

North Carolina State University is a land- Nuclear Reactor Program grant university and a constituent institution of The University of North Carolina NCSAT UNVRST Department of Nuclear Engineering Campus Box 7909 Raleigh, NC 27695-7909 919.515.2321 919.513.1276 (fax)

URL: www.ne.ncsu.edu/NRP reactor program.html 30 March 2011 Attn: Document Control Desk US Nuclear Regulatory Commission 11555 Rockville Pike Rockville, MD 20852 Re: Annual Report for 2010 In accordance with Technical Specification 6.7.4, the annual operating report for our facility is attached.

If you have any questions regarding this correspondence or require additional information, please contact Gerald Wicks at 919-515-4601 or wicks(ancsu.edu.

I declare under penalty of perjury that the forgoing is true and correct. Executed on 30 March 2011.

Aynian 1. Hawari, Ph. D.,

Director, Nuclear Reactor Program North Carolina State University

Enclosures:

Annual Operating Report for 2010 Attachnment A: PULSTAR Reactor Environmental Radiation Surveillance Report

NORTH CAROLINA STATE UNIVERSITY DEPARTMENT OF NUCLEAR ENGINEERING PULSTAR REACTOR ANNUAL REPORT DOCKET NUMBER 50-297 For the Period: 01 January 2010 - 31 December 2010 The following report is submitted in accordance with Section 6.7.4 of the North Carolina State University PULSTAR Reactor Technical Specifications:

6.7.4.a Brief Summary:

Reactor operations have been routine during this reporting period.

An unintended exposure occurred in Dec 2010 to one individual as a result of a design flaw at an experimental facility. A dose of 0.150 mrem was assigned to this individual for this incident.

Numerous corrective actions were identified and are being implemented as a result of this incident. Details of the incident were provided to the US NRC in Reportable Event 46484.

Operatingexperience including a summary of experiments performed.

Reactor operations have been routine during this reporting period. The following is a brief summary of the types of experiments performed:

Teaching Laboratories, Short Courses, and Research

  • Core thermal power measurements
  • Dynamic reactivity measurements
  • Axial power and peaking factor measurements (flux mapping)
  • Reactor power determination using photodiode arrays
  • Neutron fluence and spectral measurements
  • In-core detector certification
  • Accelerated lifetime testing for nuclear detectors
  • Neutron radiography
  • Positron production facility
  • Neutron Diffraction Neutron Activation Analysis
  • Crude oil
  • Food samples
  • Fish tissues
  • Laboratory animal tissue
  • Human hair, nails, and urine 1 of 6

Polymers and plastics P

  • Sediment/soil/rocks
  • Textiles
  • Water Ptalor Utilization by Protocol 0715 Education and Traning 11716 Research Using Irradiation Faculty 0717 Research Using Special Irradiation Facility 0718 Nuclear Services Neutron Activation Analysi 0719 Nuclea Services Isotope Production Figure 1 - Reactor Utilization by Protocol If Changes in Performance CharacteristicsRelated to Reactor Safety:

None Iii Results of Surveillance, Tests, and Inspections:

The reactor surveillance program has revealed no significant or unexpected trends in reactor systems performance during this reporting period. The Reactor Safety and Audit Committee (RSAC) performed its annual audit for the facility and determined that all phases of operation and supporting documents were in compliance.

Net loss of primary water from the reactor pool was low, but detectable in until May 2010. Net loss of primary water was not detectable after May 2010. Health physics surveillance of reactor primary coolant water showed no fission products and that activity is below 10CFR20, Appendix B, Table 3 limits for all of 2010.

2 of 6

6.7.4.b Energy Output and CriticalHours:

Total Energy Output in 2010: 56.6 Megawatt.days Critical hours in 2010: 1505.3 hours3.472222e-5 days <br />8.333333e-4 hours <br />4.960317e-6 weeks <br />1.1415e-6 months <br /> Cumulative Total Energy Output Since Initial Criticality: 1263.8 Megawatt-days 6.7.4.c Number of Emergency and Unscheduled Shutdowns:

Emergency Shutdowns - NONE Unscheduled Shutdowns - ONE

1. 13-DEC-2010 - MANUAL SHUTDOWN - Due to malfunction of the Neutron Imaging Facility.

The Reactor Operator initiated a reactor shutdown by rod insertion at the request of the Designated Senior Reactor Operator. Refer to Reportable Event 46484.

6.7.4.d Correctiveand PreventativeMaintenance:

Preventative maintenance, tests and calibrations are scheduled, performed and tracked utilizing the PULSTAR Surveillance File System. Each major component of the Reactor Safety System defined in Section 3.3, and all surveillance required by Section 4 of the Technical Specifications are monitored by this file system to ensure that maintenance and calibrations are performed in a timely manner. All historical data relating to those components, in addition to many other sub-systems, are maintained in these files.

768 - PS-6-15-1C - Radiation Recorder- A new recorder for the radiation monitoring system was installed. This replacement was a planned preventative maintenance activity.

769 - PS-1-10 T2 Temperature RTD - The unit was replaced due to deterioration of the insulation on the integral lead wire. This replacement was a planned preventative maintenance activity.

6.7.4.e Changes in Facility,Procedures,Tests, and Experiments:

Facility Changes Design changes to the reactor facility were reviewed to determine whether or not a 10CFR50.59 evaluation was required. Based on the reviews, none required a 10CFR50.59 evaluation.

The following design changes were made:

710 - Installation of Air Effluent Probes- Air effluent probes are being relocated from the exhaust stack to exhaust ducts inside the reactor building. The relocation will facilitate inspection and maintenance on the sampling probes. The modification was approved on 22-JAN-2010 and should be completed by summer 2011.

3 of 6

Document Changes Procedure changes were reviewed to determine whether or not a 10CFR50.59 evaluation was required. Based on the reviews, none required a 10CFR50.59 evaluation.

709 - NRP-OP-401 Heavy Water TransferRev. 0. This is a new procedure for the purpose of providing directions for the transfer of heavy water between storage drums, tanks, or experimental equipment with regard to the Ultra-cold Neutron Facility.

711 - PS-6-12-1:B W1/M1/A I Primaryand Secondary Water Chemistry Rev. 2. - An alternative method for determining the Purification System Decontamination Factor (DF) was added to the procedure.

712 - NRP-OP-101 Reactor Startup and Shutdown Rev. 7. This was a classified as a minor change. Verbiage specific to the replacement Radiation Recorder was modified. Other typographical errors were corrected.

Test and Experiments There were no new experiments or changes to existing experiments.

Other Changes There were no other changes.

6.7.4.f RadioactiveEffluent:

Liquid Waste (summarized by quarters)

Radioactivity Released During the Reporting Period:

(1) (2) (3) (4)1 (5)

Period Number of Total Total Diluent Tritium Batches Pci Volume Liters pci Liters 01 JAN- 31 MAR 10 2 34 6.3 E3 1.5 E4 32 01 APR- 30 JUN 10 2 23 5.5 E3 4.8 E3 22 01 JUL- 30 SEP 10 3 69 1.0 E4 2.1 E4 66 01 OCT- 31 DEC 10 1 17 3.3 E3 4.3 E3 16 2010 136 pCi of tritium was released during this year.

2010 143 pCi of total activity was released during this year.

'Based on gross beta activity only. Tritium did not require further dilution.

ii. Identification of Fission and Activation Products:

The gross beta-gamma activity of the batches in (i) above were less than 2x 10-5 pCi/ml. Isotopic analyses of these batches indicated low levels of typical corrosion and activation products. No fission products were detected.

iii. Disposition of Liquid Effluent not Releasable to Sanitary Sewer System:

All liquid effluent met the requirements of 10CFR20 for release to the sanitary sewer.

4 of 6

Gaseous Waste (summarized monthly)

Radioactivity DischargedDuring the Reporting Period(in Curies) for:

(1) Gases:

Year Month Total Time Curies Hours 2010 JANUARY 744 0.433 FEBRUARY 672 0.651 MARCH 744 0.423 APRIL 720 0.595 MAY 744 0.780 JUNE 720 0.673 JULY 744 0.587 AUGUST 744 0.953 SEPTEMBER 720 1.020 OCTOBER 744 2.190 NOVEMBER 720 1.280 DECEMBER 744 0.487 TOTAL 8760 10.069 (2) Particulateswith a half-life of greaterthan eight days:

Particulate filters from the Stack Particulate Monitoring Channel were analyzed upon removal.

There was no particulate activity with a half-life greater than 8 days indicated on any filter during this reporting period.

ii. Gases and ParticulatesDischargedDuring the Reporting Period:

(1) Gases:

Total activity of Argon-41 released was 10.069 curies in 2010.

The yearly average concentration of Argon-41 released from the PULSTAR reactor facility exhaust stack in 2010 was 3.8x10 8 pCi/ml. Dose calculations for the year were performed using methods given in the Final Safety Analysis Report. Dose calculations gave results less than the 10CFR20 constraint level of 10 mrem. These results are consistent with environmental monitoring data given in Attachment A.

(2) Particulates:

Refer to gaseous waste i.(2) above.

Solid Waste from Reactor

i. Total Volume of Solid Waste Packaged 58 ft 3 of dry uncompacted waste.

No spent ion exchange resins were disposed.

5 of 6

ii. Total Activity Involved 1.033 mCi of dry uncompacted waste.

No spent ion exchange resins were disposed.

iii. Dates of shipments and disposal Transfers to the university broad scope radioactive materials license were made on 7 May 2010, 20 May 2010, 18 Jun 2010, and 6 Dec 2010. The University Environmental Health and Safety Center arranges disposal of hazardous wastes.

6.7.4.g PersonnelRadiation Exposure Report:

33 individuals were monitored for external radiation dose during the reporting period. Internal dose monitoring was not required for any individual. Collective deep dose-equivalent for 1 Jan 2010 to 31 Dec 2010 was 2.689 person-rem. Individual deep dose-equivalent ranged from 0.002 rem to 0.644 rem with a median of 0.053 rem.

An unintended exposure occurred in Dec 2010 to one individual as a result of a design flaw with an experimental facility. A dose of 0.150 mrem was assigned to this individual for this incident.

Numerous corrective actions were identified and are being implemented as a result of this incident. Details of the incident were provided to the US NRC in Reportable Event 46484.

6.7.4.h Summary of Radiation and ContaminationSurveys Within the Facility:

Radiation and contamination surveys performed within the facility by the PULSTAR staff indicated that:

  • Radiation in the majority of areas was 5 mrem/h or less.
  • Radiation in the remaining areas were higher due to reactor operations.
  • Contamination in most areas was not detectable. When contamination was detected, the area or item was confined or decontaminated.

6.7.4.i Descriptionof EnvironmentalSurveys Outside of the Facility:

Refer to Attachment A prepared by the Radiation Safety Division of the Environmental Health and Safety Center at the end of this document for results of environmental sampling and analysis.

Perimeter surveys were performed adjacent to the Reactor Building by the PULSTAR staff and indicated that:

Radiation was at background levels for most areas (average background is approximately 10 pIrem/h).

  • Contamination was not detectable.
  • Net radiation readings ranged from 0 to 50 prem/h while the reactor was operating at power. However, radiation was at background levels in all routinely occupied spaces.

6 of 6

ATTACHMENT A PULSTAR REACTOR ENVIRONMENTAL RADIATION SURVEILLANCE REPORT FOR THE PERIOD JANUARY 1, 2010 - DECEMBER 31, 2010 NORTH CAROLINA STATE UNIVERSITY ENVIRONMENTAL HEALTH AND SAFETY CENTER RADIATION SAFETY DIVISION by Ralton J. Harris Environmental Health Physicist

TABLE OF CONTENTS PAGE NO.

1. INTRODUCTION 1 Table 1 Environmental Monitoring Programs for the PULSTAR Reactor 2
2. AIR MONITORING 3 Table 2.1 Location of Air Monitoring Stations 3 Table 2.2 Aerially Transported Gamma Activity (LLD Values) 4 Figures 2a-2e Airborne Gross Beta Activities 5-9 Table 2.3 Regulatory Limits, Alert Levels and Background Levels for Airborne Radioactivity 10
3. MILK Table 3.1 1-131 in Cow' s Milk 11
4. SURFACE WATER Table 4.1 Gross Alpha and Beta Activity in Surface Water 12 Table 4.2 LLD Values for Gamma Emitters in Surface Water 13
5. VEGETATION Table 5.1 Gross Beta Activity in Campus Vegetation 14 Table 5.2 LLD Values for Gamma Emitters in Vegetation 15
6. THERMOLUMINESCENT DOSIMETERS 16 Table 6.1 Environmental TLD Exposures 17
7. QUALITY CONTROL INTERCOMPARISON PROGRAM 18 Tables 7.1 a - 7.le 19-22
8. CONCLUSIONS 23 APPENDIX 1 24-28
1. INTRODUCTION The Environmental Radiation Surveillance Program exists to provide routine measurements of the university environment surrounding the PULSTAR Reactor.

The specific objectives of this program include:

1) Providing information that assesses the adequacy of the protection of the university community and the public-at-large;
2) Meeting requirements of regulatory agencies;
3) Verifying radionuclide containment in the reactor facility;
4) Meeting legal liability obligations; and
5) Providing public assurance and acceptance.

1

Table 1:

Environmental Monitoring Programs for the PULSTAR Reactor at North Carolina State University Sample Activity Conducted Previous Current Basis For Measured By Frequency Frequency Measurement Stack Gross N.E. Continuous Continuous 10 CFR 20 Gases Gamma T.S. 6.7.4 Stack Gross Beta N.E. Monthly Monthly 10 CFR 20 Particles Indiv. N.E. T.S. 6.7.4 Gamma Emitters Water from Gross Beta N.E. Prior to Prior to 10 CFR 20 Reactor Gross N.E. Discharge Discharge T.S. 6.7.4 Facility Gamma N.E. (~ Monthly) - Monthly City of Tritium Raleigh Ordinance Air/Particles Gross Beta RSD/EHSC Weekly Quarterly 10 CFR 20 at 5 Indiv. RSD/EHSC Weekly 10 CFR 20 Campus Gamma Stations* Emitters Air/Dosage TLD RSD/EHSC Quarterly Quarterly 10 CFR 20 at 8 Dosimeter Campus Stations+

Surface Gross Beta RSD/EHSC Quarterly Quarterly NCSU Water Indiv. RSD/EHSC Quarterly Quarterly NCSU Rocky Gamma Branch Emitters Creek Vegetation Gross Beta RSD/EHSC Semi- Alternate years NCSU NCSU Gamma RSD/EHSC annually Alternate years NCSU Campus I IIII Milk 1-131 RSD/EHSC Monthly Alternate years NCSU Local Dairy N.E. = Nuclear Engineering/Reactor Facility; RSD/EHSC = Radiation Safety Division.

  • These 5 stations include: Withers, Daniels, Broughton, Hill Library and Environmental Health & Safety Center.

+These 8 stations include: the PULSTAR Reactor, a control station (EHSC) and the 5 air sampling stations, and North Hall.

2

2. AIR MONITORING (TABLES 2.1, 2.2, AND 2.3; FIGURES 2a THROUGH 2e)

Air monitoring is performed continually for one week during each of four (4) quarters during the year. The data shows the normal fluctuations in gross beta activity levels expected during the year. Figures 2a through 2e show bar graphs of gross beta activity (fCi/cubic meter vs. sampling quarters per year). The highest gross beta activity observed was 19.0 fCiM-3 at the Withers Hall station during the week of 10/15/10 to 10/21/10. The annual campus average was 11.6 fCiM 3.

Table 2.2 lists LLD values for several gamma emitters which would be indicative of fission product activity. No gamma activity due to any of these radionuclides was detected.

Table 2.3 lists regulatory limits, alert levels, and average background levels for airborne radioactivity.

TABLE 2.1 LOCATION OF AIR MONITORING STATIONS 2 3 SITE DIRECTION 1 DISTANCE ELEVATION (meters) (meters)

BROUGHTON SOUTHWEST 125 -17 LIBRARY NORTHWEST 192 +11 DANIELS SOUTHEAST 90 -8 WITHERS NORTHEAST 82 -6 EH & S CENTER WEST 1230 -3 NORTH HALL NORTHEAST 402 -4 1DIRECTION - DIRECTION FROM REACTOR STACK 2 DISTANCE - DISTANCE FROM REACTOR STACK 3 ELEVATION

- ELEVATION RELATIVE TO THE TOP OF THE REACTOR STACK 3

Table 2.2 Aerially Transported Gamma Activity LLD values fCi/cubic meter K

.. . .. . . .. ... T._ NUCLIDES SAMPLING PERIOD [ Co-57 Co-60 " Nb-95 "r Ru-103 ....Ru-1O6 Cs-1 37 Ce-141 Ce-144 2010 03125 - 03131 -. 0.21 0.35 0.29 0.47 0.27 2.37 0.26 0.38 1.22 06/12 - 06/18 0.2 0.37 0.28 0...48 ... 0.29 0.34_ 1.28 09/15 - 09/22 0.18 0.35 0.31 0.54 0.33 2.5.1.. 0.29 _0.43 1.40 10/15 - 10/21 0.17 0.37 0.37 0.50 0.32 2.41 0.29 0.39 1.41

Broughton Hall 25 Airborne Gross Beta Activity Figure 2a

.06112-06118 20 2010 E. 09115-09/22 0 03125-03131 15 2010 B 2010 10115-10121 10 2010 5

0 2 3 4 Quarters per Year

Withers Hall 25 -Airborne Gross Beta Activity Figure 2b 10115-10121 2010 20 15 03125-03/31 06112-06118 09115.-09122 2010 2010 20 10 5 -

10 2 3 4 Quarters per Year

Daniels Hall 25 Airborne Gross Beta Activity Figure 2c 20 10115-10121 1~

4~5 2010 0)

E 15 03125-03131 06112-06118 09/15-09122 U 2010 2010 2010

-o U 10 C-,

4-5 0

1 2 3 4 Quarters per Year

D.H. Hill Library 25 Airborne Gross Beta Activity Figure 2d 20 4)

E 15 00 U

.0 U 10 0

5 0

2 3 4 Quarters per Year

Environmental Health & Safety Center Airborne Gross Beta Activity 25 Figure 2e 20 15 03/25-03/31 09/15-09122 10115-10/21 E 2010 2010 2010 10 IN

.. 10 06/12-06/18

~2010 5 1 0~

2 3 4 Quarters per Year

TABLE 6.1 ENVIRONMENTAL TLD EXPOSURES (mrem/QUARTER YEAR)

DATE WITHERS DANIELS BROUGHTON DH HILL* EH&S PULSTAR NORTH CONTROL 2010 01/01-03/31 M 7 3 22,32,42 7 23 6 M,6 04/01-06/30 M 2 5 28,23.35 7 24 9 M**

07/01-09/30 2 5 3 24,35,30 7 29 8 M,6 10t01-12131 1 7 3 30,32,27 7 14 6 M,7

  • Entries for D.H. Hill are for three (3) independent dosimeter readings for that station.

Entries for CONTROL are for two (2) independent dosimeter readings in two (2) separate office locations.

Only one control reading was available The designation "M" is used by the contract vendor for reporting dose equivalents below the minimum measurable quantity which is 1 millirem for gamma radiation and 10 millirem for beta radiation All values reported are Deep DDE

TABLE 2.3 REGULATORY LIMITS, ALERT LEVELS, AND BACKGROUND LEVELS FOR AIRBORNE RADIOACTIVITY (fCi M-3 ).

REGULATORY ALERT AVERAGE N.C.

NUCLIDE LIMIT LEVEL BACKGROUND LEVEL GROSS ALPHA 20 10 4 GROSS BETA* 1000 500 3.3 -13.9

  • Cs-137 5X10 5 10 2 Ce-144 2 X 105 100 0 Ru-106 2X105 30 0 1-131 1X 5 10 0
  • These data represent a range of minimum to maximum annual average values measured in North Carolina.

10

3. MILK (TABLE 3.1)

Milk samples are collected in alternate years from the Campus Creamery and the Lake Wheeler Road Dairy and analyzed for 1-131. No milk samples were collected for 2010. The next sample collection and analysis will be in 2011.

TABLE 3.1A 1-131 IN COW'S MILK (pCi Liter 1 +/- 2 a) LLD - 3 pCi Liter 1 pCi Liter- 1 DATE Campus Creamery Lake Wheeler 2010 No Data No Data 11

4. SURFACE WATER (TABLES 4.1 AND 4.2)

Table 4.1 gives the gross alpha and beta activities for water from Rocky Branch at points where it enters (ON) and exits (OFF) the campus. The LLD value for gross alpha and beta activities is - 0.4 pCi Liter 1 . For gross alpha activity the Alert Level is 5 pCi Liter' and the Regulatory Limit is 15 pCi Liter 1 . For gross beta activity the Alert Level is 5 pCi Liter 1 and the Regulatory Limit is 50 pCi Liter'.

Samples with gross alpha or beta activities exceeding these Alert Levels would require gamma analysis to identify the radionuclides present. All the results are consistent with the presence of naturally-occurring radionuclides and none of the gamma emitters listed in Table 4.2 were detected.

1 +/- 2y)

TABLE 4.1 GROSS ALPHA AND BETA ACTIVITY IN SURFACE WATER (pCi Liter

  • LLD, - 0.4 pCi Liter-1 LLDp - 0.4 pCi Liter -

pCi Liter -1 GROSS GROSS DATE LOCATION ALPHA BETA FIRST QUARTER 2010 ON < 0.4 2.7 +/- 0.7 OFF 0.6 +/- 0.3 2.1 +/-0.7 SECOND QUARTER 2010 ON < 0.4 3.2 +/- 0.7 OFF 0.4 +/- 0.3 3.1 +/-0.7 THIRD QUARTER 2010 ON 0.5 +/- 0.3 3.4 + 0.7 OFF < 0.4 3.1 +0.7 FOURTH QUARTER 2010 ON < 0.4 3.4 + 0.7 OFF < 0.4 3.1 +0.7 12

TABLE 4.2 LLD VALUES FOR GAMMA EMITTERS IN SURFACE WATER NUCLIDE LLD (pCi Liter-1)

Co-60 0.4 Zn-65 0.7 Cs-137 0.3 Cs-134 0.4 Sr-85 0.4 Ru-103 0.3 Ru-106 3.0 Nb-95 0.4 Zr-95 0.5 13

5. VEGETATION (TABLE 5.1 & 5.2)

Tables 5.1 gives gross beta activities for grass samples collected on the NCSU Campus. Table 5.2 lists LLD values for several gamma emitters. The vegetation sampling is performed in alternate years.

No vegetation samples were collected in 2010. The next sample collection and analysis will be in 2011.

1 TABLE 5.1 GROSS BETA ACTIVITY IN CAMPUS VEGETATION

  • LLD - 0.5 pCi g-SAMPLE DATE SAMPLE LOCATION (P~i q"+/-2a 2010 NORTH CAMPUS No Data 2010 SOUTH CAMPUS No Data 2010 EAST CAMPUS No Data 2010 WEST CAMPUS No Data 14

TABLE 5.2 LLD VALUES FOR GAMMA EMITTERS IN VEGETATION NUCLIDE LLD (pCi gram-)

Co-60 0.01 Zn-65 0.02 Cs-137 0.01 Cs-134 0.01 Sr-85 0.01 Ru-103 0.01 Nb-95 0.01 Zr-95 0.02 15

6. THERMOLUMINESCENT DOSIMETERS (TLDs) (TABLE 6.1)

TLD analysis is contracted to Landauer, Inc. for determination of ambient gamma exposures.

Exposures are integrated over a three-month period at each of the five air monitor stations listed in Table 2.1 and inside the PULSTAR Reactor building (In July 2006, the dosimeter previously located in the PULSTAR stack was relocated inside the reactor building at the exhaust duct) and at North Hall. A control station is located in two office locations of the Environmental Health & Safety Center. Table 6.1 gives the data for these eight (8) locations.

The exposures (dose equivalents) are reported as millirem per quarter year. Readings falling below the dosimeters' minimum measurable quantities (i.e., 1 millirem for gamma radiations and 10 millirems for beta radiations) are reported by the contract vendor with the designation "M". The observed readings are all within the expected range for natural background radiation levels.

Historically, dosimeter readings for D.H. Hill Library monitoring station have often been higher than those for the other campus stations due to its location inside a concrete penthouse. Pursuant to a recommendation made in the NCSU PULSTAR 2001 Annual Self Assessment, two additional TLDs are included at the D.H. Hill Library station to supplement the existing dosimeter. These two additional dosimeters are a routine part of the quarterly monitoring schedule.

16

TABLE 6.1 ENVIRONMENTAL TLD EXPOSURES (mrem/QUARTER YEAR)

DATE WITHERS DANIELS BROUGHTON DH HILL* EH&S PULSTAR NORTH CONTROL 2010 01/01-03/31 M 7 3 22,32,42 7 23 6 M,6 04/01-06/30 M 2 5 28,23,35 7 24 9 07/01-09/30 2 5 3 24,35,30 7 29 8 M,6 10/01-12/31 1 7 3 30,32,27 7 14 6 M,7

  • Entries for D.H. Hill are for three (3) independent dosimeter readings for that station.

Entries for CONTROL are for two (2) independent dosimeter readings in two (2) separate office locations.

Only one control reading was available The designation "M" is used by the contract vendor for reporting dose equivalents below the minimum measurable quantity which is 1 millirem for gamma radiation and 10 millirem for beta radiation All values reported are Deep DDE

7. QUALITY CONTROL INTERCOMPARISON PROGRAM The Environmental Radiation Surveillance Laboratory (ERSL) of the Radiation Safety Division has analyzed samples provided by the U.S. DOE Mixed-Analyte Performance Evaluation Program (MAPEP Test Session 22) Radiological and Environmental Sciences Laboratory (RESL) during this reporting period. The objective of this program is to provide laboratories performing environmental radiation measurements with unknowns to test their analytical techniques.

The MAPEP value listed in the Tables 7.1 (a-e) to which the ERSL results are compared is the mean of replicate determinations for each nuclide. The MAPEP uncertainty is the standard error of the mean.

For each reported radiological and inorganic analyte, the laboratory result and the RESL reference value may be used to calculate a relative bias:

%Bias = (100)(Laboratory Re suit - RESL Re ferenceValue)

RESL Re ferenceValue The relative bias will place the laboratory result in one of three categories:

Acceptable ..................... Bias < 20%

Acceptable with Warning... 20% < Bias < 30%

Not Acceptable ................ Bias > 30%

In addition to the MAPEP Quality Assurance Program, the ERSL conducts an intralaboratory QC program to track the performance of routine radioactivity measurements. The types of calculations employed for this program are shown in an example calculation in Appendix 1.

18

TABLE 7.1a GROSS ALPHA & BETA ACTIVITY AIR FILTER--INTERCOMPARISON STUDY 01 March 2010 The sample consists of one 50 mm diameter simulated filter spiked with a matrix-free solution containing a single alpha and a single beta emitting nuclide. The reported values and the known values are given in Bqlfilter.

  • NCSU - ENVIRONMENTAL LABORATORY RESULTS Radionuclide *Reported *Reported MAPEP Acceptance Value Error Value Range Gross Alpha 0.54 0.05 0.427 > 0.0 - 0.854 Gross Beta 1.25 0.06 1.29 0.65 - 1.94 19

TABLE 7.1b MULTINUCLIDE AIR FILTER - INTERCOMPARISON STUDY 01 March 2010 The sample consists of one 7 cm diameter glass fiber filter that has been spiked with 0.10 gram of solution and dried. The reported values and the known values are given in Bq/filter.

  • NCSU - ENVIRONMENTAL LABORATORY RESULTS Radionuclide *Reported *Reported MAPEP Acceptance Value Error Value Range Co60 2.50 0.05 2.473 1.731 - 3.215 Cs137 1.59 0.04 1.53 1.07-1.99 Cs134 1.61 0.03 2.13 1.49 - 2.77 Co57 NR Mn54 3.27 0.07 3.02 2.11 -3.93 Zn65 NR NR = No Result. These were tests for false positive results. No analyte present.

20

TABLE 7.1c MULTINUCLIDE WATER SAMPLE - INTERCOMPARISON STUDY 01 March 2010 The sample consists of a spiked, 455 mL aliquot of acidified water (-1 N HCI). The reported values and the known values are given in BqlLiter.

  • NCSU - ENVIRONMENTAL LABORATORY RESULTS Radionuclide *Reported *Reported MAPEP Acceptance Value Error Value Range Co60 NR .....

Cs137 60.03 1.39 60.6 42.4 - 78.8 Cs134 NR .....

Co57 26.21 0.75 28.3 19.8 - 36.8 Zn65 43.29 1.56 40.7 28.5 - 52.9 Mn54 26.78 0.76 26.9 18.8 - 35.0 NR = No Result. These were tests for false positive results. No analyte present.

21

TABLE 7.1d GROSS ALPHA AND BETA WATER SAMPLE - INTERCOMPARISON STUDY 01 March 2010 The sample consists of a 5% HNO 3 matrix free solution. The reported values and the known values are given in BqlLiter.

  • NCSU - ENVIRONMENTAL LABORATORY RESULTS Radionuclide *Reported *Reported MAPEP Acceptance Value Error Value Range Gross Alpha 1.66 0.42 0.676 > 0.0 - 1.352 Gross Beta 4.51 0.53 3.09 1.55 - 4.64 TABLE 7.1e MULTINUCLIDE VEGETATION SAMPLE - INTERCOMPARISON STUDY 01 March 2010 The sample consists of milled hay grass spiked with radiological constituents. The reported values and the known values are given in Bq/sample.
  • NCSU - ENVIRONMENTAL LABORATORY RESULTS Radionuclide *Reported *Reported MAPEP Acceptance Value Error Value Range Cs134 4.02 0.08 4.39 3.07 - 5.71 Cs137 3.28 0.12 3.06 2.14 - 3.98 Co57 NR Co60 3.65 0.08 3.27 2.29 - 4.25 Mn54 NR Zn65 8.19 0.24 7.10 4.97 - 9.23 NR = No Result. These were tests for false positive results. No analyte present.

22

8. CONCLUSIONS The data obtained during this period do not show any fission product activities. The observed environmental radioactivity is due primarily to radon progeny, primordial radionuclides (e.g. K-40) and those radionuclides that originate in the upper atmosphere as the result of cosmic ray interactions. These facts justify the conclusion that the PULSTAR Reactor facility continues to operate safely and does not release fission product materials into the environment.

23

APPENDIX 1 The following example calculation gives a set of data, the mean value, the experimental sigma, and the range. These statistics provide measures of the central tendency and dispersion of the data.

The normalized range is computed by first finding mean range, R, the control limit, CL, and the standard error of the range, OR. The normalized range measures the dispersion of the data (precision) in such a form that control charts may be used. Control charts allow one to readily compare past analytical performance with present performance. In the example, the normalized range equals 0.3 that is less than 3, which is the upper control level. The precision of the results is acceptable.

The normalized deviation is calculated by computing the deviation and the standard error of the mean, am. The normalized deviation allows one to measure central tendency (accuracy) readily through the use of control charts. Trends in analytical accuracy can be determined in this manner.

For this example, the normalized deviation is -0.7 which falls between +2 and -2 that are the upper and lower warning levels. The accuracy of the data is acceptable. Any bias in methodology or instrumentation may be indicated by these results.

24

EXAMPLE CALCULATIONS Experimental Data:

Known value = p 3273 pCi 3H/Liter on September 24, 1974 Expected laboratory precision = = 357 pCi/liter Sample Result X1 3060 pCi/liter X2 3060 pCi/liter X3 3240 pCi/liter Mean = x N

Xj. 9360 x = X=i = 3 3120 pCi/liter N

where N = number of results = 3 Experimental sigma = s NN s X 1x)2-i~i N N-I (3060+3060+3240)2 (3060)2+(3060)2+ (3240)2_

3 s

2 s = 103.9 pCi/liter Range r r = I maximum result - minimum result I r = 3240 - 30601 r = 180 pCi/liter 25

Range Analysis (RNG ANLY)*

Mean range R - o where d 2** = 1.693 for N = 3

= (1.693) (357)

R = 604.4 pCi/liter Control limit - CL CL R + 3oR

= D 4R where D4** = 2.575 for N = 3

- (2.575) (604.4)

CL 1556 pCi/liter Standard error of the range (JOR CY = (R+3oaR-) + 3

= (D 4R-R) + 3

= (1556-604.4) - 3 oF = 317.2 pCi/liter Let Range = r = wR + xoR = 180 pCi/liter Define normalized range = w+x for r >- R, w = 1 then r = WR +XOR -R + XOR r- P or r-therefore w+x = 1 +x = 1 +

  • Rosentein, M., and A. S. Goldin, "Statistical Techniques for Quality Control of Environmental Radioassay,"

AQCS Report Stat-1, U.S. Department of Health Education and Welfare, PHS, November 1964.

    • From table "Factors for Computing Control Limits," Handbook of Tables for Probability and Statistics, 2nd Edition, The Chemical Rubber Co., Cleveland, Ohio, 1968, p. 454.

26

forr

  • R, x=0 then r = wR+xOR = wR r

or w=

R r

therefore w+x = w+0 =

R since r < R, (180 < 604.4) 180 W+X=

604.4 w + x =0.30 Normalized deviation of the mean from the known value ND Deviation of mean from the known value = D D = i-p

= 3120 - 3273 D = -153 pCi/liter Standard error of the mean = Orm a

a-VN 357 V/3 rn = 206.1 pCi/liter D

ND-am

-153 206.1 ND = -0.7 Control limit = CL CL = (p +/-+3m) 27

Warning limit = WL WL = (p +/-2am)

Experimental sigma (all laboratories) =s N

N (E x1)2 E X. 2 - i=1 St i==-

1 62639133-(49345) 2 15 14 s, = 149 pCi/liter Grand Average = GA N

GA = i=1 N

49345 15 GA = 3290 pCi/liter Normalized deviation from the grand average = ND' Deviation of the mean from the grand average =D' D'= x- GA

= 3120 - 3290 D'= -170 pCi/liter D

ND'

-170 206.1 ND' = -0.8 28

Retrieved from "https://kanterella.com/w/index.php?title=ML110910064&oldid=2119565"