ML060610105
ML060610105 | |
Person / Time | |
---|---|
Site: | North Carolina State University |
Issue date: | 02/28/2006 |
From: | Cook A North Carolina State University |
To: | Document Control Desk, Office of Nuclear Reactor Regulation |
References | |
Download: ML060610105 (38) | |
Text
lr-*. North Carolina State University is a land- Nuclear Reactor Program grant university and a constituent institution of The.University of North Carolina
- eI+ ORIMlx~ iNK Department of Nuclear Engineering Campus Box 7909 Raleigh, NC 27695-7909 919.515.2321 919.515.5115 (fax)
URL:www.ne.ncsu.edu/NRP/reactor_
program.html February 28, 2006 TO: Nuclear Regulatory Commission Document Control Desk U.S. Nuclear Regulatory Commission Washington, DC 20555 RE: NCSU PULSTAR Annual Report License No. R-120 Docket No. 50-297 In compliance with section 6.7.4 of the North Carolina State University PULSTAR Technical Speafications, our Nuclear Reactor Program staff has prepared the attached Annual Report for the period 01 January 05 - 31 December 2005.
If you have any question please feel free to call me at (919) 515-4602.
/ Andrew T Cook I :
Associate Director Nudear Reactor Program 1c02
NORTH CAROLINA STATE UNIVERSITY DEPARTMENT OF NUCLEAR ENGINEERING PULSTAR REACTOR ANNUAL REPORT DOCKET NUMBER 50-297 For the Period: 01 January 2005 - 31 December 2005 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.
i Operating experience 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 diffusion length in graphite by foil activation
- Neutron fluence and spectral measurements
- Neutron transmutation doping of silicon
- In-core detector certification
- Radiation damage determination to fiber optic material
- Accelerated lifetime testing for nuclear detectors
- Neutron radiography
- Positron production facility Neutron Activation Analysis
- Crude oil
- Food samples
- Fish tissues 1 of 6
- Laboratory animal tissue
- Human hair, nails, and urine
- Polymers and plastics
- Sediment/soil/rocks
- Silicon crystals
- Textiles
- Water ii Changes in Performance Characteristics Related 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.
Health physics surveillance of reactor primary coolant water showed no fission products and that activity is below 10 CFR 20, App. B, Table 3 limits.
6.7.4.b Total Energy Output:
108.6 Megawatt-days Reactor was Critical:
3154.5 hours5.787037e-5 days <br />0.00139 hours <br />8.267196e-6 weeks <br />1.9025e-6 months <br /> Cumulative Total Energy Output Since Initial Criticality:
1074.1 Megawatt-days 6.7.4.c Number of Emergency and Unscheduled Shutdowns:
Emergency Shutdowns - none Unscheduled Shutdowns - Two
- 1. 20-MAR-05: Linear Over-Power SCRAM during start-up due to removal of source with Linear Channel in a low range. No actual over-power condition existed.
- 2. 19-OCT-05: Pool Temperature SCRAM due to power flicker. No actual high temperature condition existed.
6.7.4.d Corrective and Preventative Maintenance:
Preventative maintenance, tests and calibrations are scheduled, performed and tracked utilizing the PULSTAR Surveillance File System. Each major component of the Reactor Safety System 2 of 6
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.
6.7.4.e Changes in Facility, Procedures, Tests, and Experiments:
Summary:
Design Changes Numerous design changes were approved. All changes were reviewed to determine whether or not a 10CFR50.59 evaluation was required. Based on the reviews, none required a 10CFR50.59 evaluation.
Control Rod Drive Position Indication. Servo-Synchro position indication was replace with absolute rotary encoders with and analog output.
Reactor Power Recorder. The two pen/ink recorders were replaced with one LCD recorder. The recorders provide no protective actions.
Modification of Shim Rod Drive. All abandoned in place mechanisms for the pulsing capabilities were removed.
Replace N-1 6 Analog Meter. The analog meter displaying percent reactor power was replaced with a digital LED display.
Stack Radiation Monitoring System Upgrade. The stack radiation system was modified to allow on-line change-out of the particulate filter.
Document Changes Nine procedures where revised including Operational and Health Physics procedures. Five were considered procedure revisions, four were considered minor changes. All changes were reviewed to determine whether or not a 10CFR50.59 evaluation was required. Based on the reviews, none required a 10CFR50.59 evaluation.
Other Changes License Amendment was submitted to the NRC to allow receipt, possession and use of by-product material.
Physical Security Plan was revised to revision 9.
6.7.4.f Radioactive Effluent:
Liquid Waste (summarized by quarters)
- i. Radioactivity Released During the Reporting Period:
(1) (2) (3) (4)1 (5)
Period Number of Total Total Diluent Tritium Batches pCi Volume Liters piCi Liters 01 JAN - 31 MAR 04 2 45 6.0 E3 1.8 E4 43 01 APR- 30 JUN 04 2 35 4.9 E3 8.0 E3 34 01 JUL - 30 SEP 04 2 84 5.8 E3 9.7 E4 73 01 OCT - 31 DEC 04 2 155 6.8 E3 7.3 E4 147 3 of6
(6) l 297 pCi of tritium was released during this year.
(7) 1 319 gCi of total activity was released during thisyear.
'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 (1) above were less than 2x10-5 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 10 CFR 20 for release to the sanitary sewer.
Gaseous Waste (summarized monthly)
- i. Radioactivity Discharged During the Reporting Period (in Curies) for:
(1) Gases:
Year Month Total Time Curies Hours 2005 JANUARY 744 10.213 FEBRUARY 696 10.199 MARCH 744 0.404 APRIL 720 10.345 MAY 744 iD.281 JUNE 720 10.220 JULY 744 ID.124 AUGUST 744 D.290 SEPTEMBER 720 iD.092 OCTOBER 744 0.670 NOVEMBER 720 0.225 DECEMBER 744 D.597 TOTAL 8760 3.660 (2) Particulates with a half-life of greater than eight days:
Particulate filters from the Stack Particulate Monitoring Channel were analyzed upon removal.
There was no particulate activity with tl 12 >8days indicated on any filter during this reporting period.
ii. Gases and Particulates Discharged During the Reporting Period:
(1) Gases:
Total activity of argon-41 released was 3.660 curies in 2005.
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The yearly average concentration of argon-41 released from the PULSTAR reactor facility exhaust stack in 2005 was 1.2x10 -pCi/mi. Dose calculations for the fiscal year were performed using the "COMPLY" code with results less than the 10 mrem constraint level given in 10CFR20.
(2) Particulates:
See gaseous waste i.(2) above.
Solid Waste from Reactor'
- i. Total Volume of Solid Waste Packaged 65 ft3 of dry uncompacted waste 12 ft3 of dried resins.
ii. Total Activity Involved 0.2 mCi in dry compacted waste 0.5 mCi in dried resins iii. Dates of shipments and disposal Transfer to the university broad scope radioactive materials license was made on 2:7 January 2005, 23 March 2005, 15 June 2205, and 5 October 2005. The University Environmental Health and Safety Center arranges disposal of hazardous wastes.
6.7.4.g Personnel Radiation Exposure Report:
35 individuals were monitored for external radiation dose during the reporting period. Collective dose for 2005 was 2.179 person-rem. Individual doses ranged from 0.001 to 0.146 rem with an average of 0.062 rem. No visitors required official monitoring during 2005.
6.7.4.h Summary of Radiation and Contamination Surveys 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 was 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 Description of Environmental Surveys Outside of the Facility:
See Attachment A prepared by the Radiation Safety Division of the Environmental Health and Safety Center at the end of this document.
Perimeter surveys were performed adjacent to the Reactor Building by the PULSTAR staff and indicated that:
- Radiation was at background levels for most areas (10 prem/h).
- Contamination was not detectable.
5 of6
- Net radiation readings ranged from background levels to 40 prem/h in some areas 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, 2005 - DECEMBER 31, 2005 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 I 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 7.1a - 7.1d 19-22
- 8. CONCLUSIONS 23 APPENDIX I 24-28 APPENDIX 2 29
- 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 ,
Milk 1-131 RSD/EHSC Monthly Alternate years NCSU Local Dairy Abbreviations Used in Table:
N.E. = Nuclear Engineering/Reactor Facility; RSD/EHSC = Radiation Safety Division.
- These 5 stations include:
Withers, Riddick, Broughton, Hill Library and Environmental Health & Safety Center.
+These 8 stations include: the PULSTAR stack, 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 21.4 fCiM-3 at the Riddick Hall station during the week of 09/23/05 to 09/30/05. The annual campus average was 11.7 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 SITE DIRECTION' DISTANCE 2 ELEVATION 3 (meters) (meters)
BROUGHTON SOUTHWEST 125 -17 LIBRARY NORTHWEST 192 +11 RIDDICK SOUTHEAST 99 -14 WITHERS NORTHEAST 82 -6 EH & S CENTER WEST 1230 -3 NORTH HALL NORTHEAST 402 -4
'DIRECTION - DIRECTION FROM REACTOR STACK 2 DISTANCE - DISTANCE FROM REACTOR STACK 3 ELEVATION - ELEVATION RELATIVE TO THE TOP OF THE REACTOR STACK A wind rose is included in Appendix 2 to indicate the prevailing wind direction trends for the years 1996-2003.
3
Table 2.2 Aerially Transported Gamma Activity LLD values fCi/cubic meter NUCLIDES SAMPLING PERIOD Co-57 Co-60 Nb-95 Zr-95 Ru-103 Ru-106 Cs-137 Ce-141 Ce-14 2005 __
01/14-01/21 0.21 0.35 0.29 0.47 0.27 2.37 0.26 _ 0.38 1.22 05/14 - 05/20 0.2 0.37 0.28 0.48 0.28 2.48 0.29 0.34 1.28 09/23-09/30 0.18 0.35 0.31 0.54 0.33 2.51 0.29 0.43 1.40 12/09-12/15 0.17 0.37 0.37 0.50 0.32 2.41 0.29 0.39 1.41
fCilcubic meter lCll Cl l l 06 C) 0 010 011 CD~
CD w 7 ~CD n T co N)N C) N)
,N)
I h* IIII~III li i I(flN
,,,,I
- ,,.,, I .. II II.I 01 5
Withers Hall 25 T Airborne Gross Beta Activity Figure 2b 20 -
05/14-05/20 01/14-01/21 2005 2005 12/09-12/15 2005
- 4) 15 -
E 09/23-09/30 2005 U
U 10 -
W.-
5-0-
1 2 3 4 Quarters per Year
Riddick Hall 25 -- Airborne Gross Beta Activity Figure 2c 09/23-09/30 2005 12/09-12/15 20 2005 01/14-01/21 2005 05/1 4-05/20 2005
- 815 0
.0 0 ;r r g 10 5
1 2 3 4 Quarters per Year
D.H. Hill Library 25 -Airborne Gross Beta Activity Figure 2d 20 05/14-05/20 2005 09/23-09/30 12/09-12/15
. 15 2005 2005
~2 E 01/14-01/21
.0 2005 I.-
5 0 - -
1 2 3 4 Quarters per Year
Environmental Health & Safety Center Airborne Gross Beta Activity 25 Figure 2e 20 12/09-12/15 09/23-09/30 2005 2005 aE 15 0
S 10 5
0 1 2 3 4 Quarters per Year
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 13.9; 3.3*
Cs-1 37 5 X 105 10 2 Ce-144 2X 10 5 100 0 Ru-1 06 2 X 15 30 0 1-131 1 x 105 10 0
- These data represent a range of annual average values measured in North Carolina.
Data courtesy of Dale Dusenbury of the N.C. Division of Radiation Protection.
- 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. Data given for the year 2005 shows that no 1-131 activity was detected. The next sample collection will be in 2007.
TABLE 3.1A 1-131 IN COW' S MILK (pCi Liter-' +/- 2 a) LLD - 3 pCi Liter" PCi Liter-'
DATE Campus Creamery Lake Wheeler May 2005 <3 <3 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'. For gross alpha activity the Alert Level is 5 pCi Liter' and the Regulatory Limit is 15 pCi Liter1 . For gross beta activity the Alert Level is 5 pCi Liter' 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 wvere detected.
TABLE 4.1 GROSS ALPHA AND BETA ACTIVITY IN SURFACE WATER (pCi Liter' +/- 26)
- LLD, - 0.4 pCi Liter' LLDp - 0.4 pCi Liter 1 pCi Liter-'
GROSS GROSS DATE LOCATION ALPHA BETA FIRST QUARTER 2005 ON <0.4 2.5 +/- 0.7 OFF <0.4 2.7 +/- 0.7 SECOND QUARTER 2005 ON <0.4 -2.1 +/- 0.7 OFF <0.4 2.7 +/- 0.7 THIRD QUARTER 2005 ON <0.4 3.0 + 0.7 OFF <0.4 2.8 + 0.7 FOURTH QUARTER 2005 ON <0.4 3.7 + 0.7 OFF <0.4 3.6 + 0.7 12
TABLE 4.2 LLD VALUES FOR GAMMA EMITTERS IN SURFACE WATER NUCLIDE LLD (DCi Liter 1)
Co-60 0.4 Zn-65 0.7 Cs-137 0.3 Cs-134 0.4 Sr-85 0.4 Ru-1 03 0.3 Ru-1 06 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.
All the results are consistent with the presence of naturally-occurring radionuclides and none of the gamma emitters listed in Table 5.2 were detected. The next sample collection will be in 2007.
TABLE 5.1 GROSS BETA ACTIVITY IN CAMPUS VEGETATION
- LLD - 0.5 pCi g-1 SAMPLE DATE SAMPLE LOCATION (oci Q' +/- 2ay) 06/03/2005 NORTH CAMPUS 2.0+/- 0.2 06/03/2005 SOUTH CAMPUS 1.9+/-0.2 06/03/2005 EAST CAMPUS 1.6 +/- 0.2 06/03/2005 WEST CAMPUS 1.7 +/- 0.2 14
TABLE 5.2 LLD VALUES FOR GAMMA EMITTERS IN VEGETATION NUCLIDE LLD (pCi gram-')
Co-60 0.01 Zn-65 0.02 Cs-1 37 0.01 Cs-1 34 0.01 Sr-85 0.01 Ru-1 03 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 stack and at North Hall. A control station is located in Room 107 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 which fall 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 WITHERSjRibDI" ROUGHTON ODH HILL* EH&S PULSTAR STACK NORTH CONTF :OL ---- --
2005 A1f4 llv l-4
^ 1I -_ L0 Mn ) v7 7 Lf,V- e vi 04/01-06/30 = 4 14 7 23,27,29 8 4 2 M,8 07/01-09/30 3 10 2 19,20,50 7 3 2 M,3 10/01-12/31 3 7 3 42,45 7 8 7 M,7
- The entries for D.H. Hill are for three (3) independent dosimeter readings for that station. Only 2 results were reported by th a vendor for the 4th quarter 2005.
The "CONTROL" column indicates the use of dual control dosimeters for all the monitoring periods.
I T -- I I I II 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 11 I I l I
- 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 Sessions 13 and 14) 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-d) 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 (1 OO)(Laboratory Re sult - 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 July 2005 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 Bq/filter.
- NCSU - ENVIRONMENTAL LABORATORY RESULTS Radionuclide *Reported *Reported MAPEP Acceptance Value Error Value Range Gross Alpha 0.525 0.116 0.482 >0.0 - 0.80 Gross Beta 0.869 0.057 0.827 0.55 - 1.22 19
TABLE 7.1b MULTINUCLIDE AIR FILTER - INTERCOMPARISON STUDY 01 July 2005 The sample consists of one 7 cm diameter glass fiber filter which 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 2.817 0.155 2.85 2.00 - 3.71 Cs137 2.109 0.121 3.23 2.26 - 4.20 Cs134 1.964 0.121 3.85 2.70 - 5.01 Co57 5.930 0.268 6.20 4.34 - 8.06 MnS4 4.543 0.214 4.37 3.06 - 5.68 Zn65 5.063 0.324 4.33 3.03 - 5.63 20
TABLE 7.1c MULTINUCLIDE WATER SAMPLE - INTERCOMPARISON STUDY 01 July 2005 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 Bq/Liter.
- NCSU - ENVIRONMENTAL LABORATORY RESULTS Radionuclide *Reported *Reported MAPEP Acceptance Value Error Value Range Co6O 260.123 8.316 261 182.70 - 339.30 Cs137 314.194 19.226 333 233.10 - 432.90 Cs134 142.218 5.186 167 116.90 - 217.10 Co57 391.021 26.394 272 190.40 - 353.60 Mn54 398.881 18.434 418 293.60- 543.40 Zn65 342.210 14.502 330 231.00- 429.00 21
TABLE 7.1d GROSS ALPHA AND BETA WATER SAMPLE - INTERCOMPARISON STUDY 01 January 2005 The sample consists of a 5%HNO 3 matrix free solution. The reported values and the known values are given in Bq/Liter.
- NCSU - ENVIRONMENTAL LABORATORY RESULTS Radionuclide *Reported *Reported MAPEP Acceptance Value Error Value Range Gross Alpha 0.68 0.34 0.525 > 0.0 - 1.05 Gross Beta 1.64 0.45 1.67 0.83 - 2.50 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 which 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 I 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 which 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 which 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 3 H/Liter on September 24, 1974 Expected laboratory precision = o = 357 pCi/liter Sample Result X 3060 pCiliter X2 3060 pCi/liter X3 3240 pCVliter Mean =x N
9360 x = X=i = 3 = 3120 pCi/liter N
where N = number of results = 3 Experimental sigma = s
. N s 2)-_ 1=1
= N (3060)2+ (3060)2+(3240) 2_ (3060+3060+324) 2 s 2 s = 103.9 pCi/liter Range = r r = I maximum result - minimum result I r = 13240 - 30601 r = 1 80 pCiliter 25
Range Analysis (RNG ANLY)*
Mean range = R
= d2 a where d2** = 1.693 for N = 3
= (1.693) (357)
= 604.4 pCi/liter Control limit = CL CL =R + 3R
= D4R where D4** = 2.575 for N = 3
= (2.575) (604.4)
CL = 1556 pCi/liter Standard error of the range = OR YR = (R + 30R- R) + 3
= (D4 R - R) . 3
= (1556 - 604.4) . 3 OR = . 317.2 pCi/liter Let Range = r = wR + xaR = 180 pCi/liter Define normalized range = w + x for r > R, w = 1 then r = wR + xaR = R + xg, r- R or r -R therefore w+x = 1 +x = 1 +
- Rosentein, M., and A. S. Goldin, "Statistical Techniques for Quality Control of Environmental Radioassay,"
AQCS Reoort 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
forrgFR, x=o then r = WR+XCR = wR r
or w=
R r
therefore w + x = w+0 =
since r < A, (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 = x-"
= 3120 - 3273 D = -153pCi/liter Standard error of the mean = am am ON 357 V3 am = 206.1 pCi/liter D
ND =
Cm
-153 206.1 ND = -0.7 Control limit = CL CL = (p
- 3c,.)
27
Warning limit = WL WL = (p +/- 2am)
Experimental sigma (all laboratories) = s, N
N (E Xi) 2 162639133 _(49345)2 1
15 14 s, = 149 pCi/liter Grand Average = GA N
Exi GA N
49345 15 GA = 3290 pCi/liter Normalized deviation from the grand average = ND' Deviation of the mean from the grand average = D' D' = - GA
= 3120 - 3290 D'= -170 pCi/liter ND _
am
-170 206.1 ND' = -0.8 28
Joint Frequency Distribution Based on Hourly Observations from Raleigh-Durham Airport July 1, 1996 - August 24, 2003 N
- 12.10 2.16 2.38 by W E 10.56 S
e -IC_ Calms included at center.
3 6 12 18 24 Rings drawn at 5% intervals.
0.1 Wind flow is FROM the directions shown.
Wind Speed (Miles Per Hour) No observations were missing.
29