North Carolina State University is a land- Grant university and a constituent institution Of The University of North Carolina Nuclear Reactor Program The Universitv of North Carolina oWV1TWVM9- An Equal Opportunity/Affirmative Action Employer Nuclear Reactor Program Campus Box 7909 Raleigh, North Carolina 27695 http:/Awww.ne.ncsu.edu/nro/index.htmi Director Office (Fax) 919.515.4598 919.515.7294 919.513.1276 Shipping Address: NC State University 2500 Stinson Dr. Raleigh, NC 27695 29 March 2012 Attn: Document Control Desk US Nuclear Regulatory Commission 11555 Rockville Pike Rockville, MD 20852 Re: Annual Report for 2011 License No. R-120 Docket No. 50-297 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 wicksgncsu.edu. I declare under penalty of perjury that the forgoing is true and correct. Executed on 29 March 2012. Ayman I. Hawari, Ph. D., Director, Nuclear Reactor Program North Carolina State University Enclosures: Annual Operating Report for 2011 Attachment A: PULSTAR Reactor Environmental Radiation Surveillance Report ýCwo tu tot,
Transcript
North Carolina State University is a land-Grant university and a constituent institutionOf The University of North Carolina
Nuclear Reactor Program
The Universitv of North CarolinaoWV1TWVM9- An Equal Opportunity/Affirmative Action Employer Nuclear Reactor Program
Re: Annual Report for 2011License No. R-120Docket No. 50-297
In accordance with Technical Specification 6.7.4, the annual operating report for our facility isattached.
If you have any questions regarding this correspondence or require additional information, pleasecontact Gerald Wicks at 919-515-4601 or wicksgncsu.edu.
I declare under penalty of perjury that the forgoing is true and correct. Executed on 29 March 2012.
Ayman I. Hawari, Ph. D.,Director, Nuclear Reactor ProgramNorth Carolina State University
For the Period: 01 January 2011 - 31 December 2011
The following report is submitted in accordance with Section 6.7.4 of the North Carolina State UniversityPULSTAR Reactor Technical Specifications:
6.7.4.a Brief Summary:
Reactor operations have been routine during this reporting period with one exception. In July2011 an unaccounted loss of approximately 3600 gallons of primary water occurred over a periodof 14 days. Information on this abnormality is provided in "Results of Surveillance, Tests, andInspections" below.
i Operating experience including a summary of experiments performed.
Reactor operations have been routine during this reporting period. The following is a briefsummary 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
* Polymers and plastics
1
0
* Sediment/soil/rocks
* Silicon crystals
* Textiles
* Water
718 Nuclear Services NeutronActivation Analysis
5%
Reactor Utilization - 2011719 Nuclear ServicesIsotope Production
1%
Figure 1 - Reactor Utilization by Protocol
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 reactorsystems 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 andsupporting documents were in compliance.
2
From 1 July 2011 to 14 July 2011 an unaccounted loss of approximately 3600 gallons of primarywater occurred. The water loss stopped following the detection and repair of a leak site in thereactor pool liner. No primary water was found either inside or outside of the reactor facility. Itwas assumed the water was leaking into the ground surrounding the reactor site. Theradioactivity present in the reactor water met regulatory limits for release to unrestricted areas (10CFR 20 Appendix B Table 2). Local, State of North Carolina, and Federal regulators wereinformed of the abnormal release.
The frequency and types of analyses of water from a nearby creek was increased following thisabnormal water loss. Only natural radioactivity has been detected in water collected from thecreek. Net unaccounted loss of primary water from the reactor pool was not detectable for allother dates in 2011.
The cause of the unaccounted loss of primary water was determined to be a thermal shockcaused by inadvertent operation of the secondary cooling system with the reactor shut down. Asecondary pump trip on low reactor pool temperature has been installed to prevent recurrence.
6.7.4.b Energy Output and Critical Hours:
Total Energy Output in 2011: 177.56 Megawatt.days
Critical hours in 2011: 4410.27 hours
Cumulative Total Energy Output Since Initial Criticality: 1441.36 Megawatt.days
6.7.4.c Number of Emergency and Unscheduled Shutdowns:
Emergency Shutdowns - NONE
Unscheduled Shutdowns - SEVEN
16APR2011
20MAY2011
01JUN2011
03JUN2011
18JUN2011
12SEP2011
Loss of commercial power due to thunderstorm. Operator responded as perprocedure. Operations resumed once power was restored and after stormscleared the area.
Reactor SCRAM (manual) due to fire alarm activation. Operator responded asper procedure. No actual fire existed. Operations resumed after building clearedby Fire Marshall.
Loss of commercial power due to power flicker. Operator responded as perprocedure. Operations resumed once power was restored.
Reactor SCRAM (automatic) due to failed UPS. Operator responded as perprocedure. UPS replaced with spare unit.
Loss of commercial power due to power flicker. Operator responded as perprocedure. Operations resumed once power was restored.
Reactor SCRAM (manual) due to normal testing of radiation interlocks. No actualhigh radiation condition existed. Operator was retrained in the proper response toHigh Radiation Entry Alarms during normal testing of interlock devices.
3
29NOV2011 Reactor SCRAM (manual) due to normal testing of radiation interlocks. No actualhigh radiation condition existed. Operator was retrained in the proper response toHigh Radiation Entry Alarms during normal testing of interlock devices.
6.7.4.d Corrective and Preventative Maintenance:
Preventative maintenance, tests and calibrations are scheduled, performed and tracked utilizingthe PULSTAR Surveillance File System. Each major component of the Reactor Safety Systemdefined in Section 3.3, and all surveillance required by Section 4 of the Technical Specificationsare monitored by this file system to ensure that maintenance and calibrations are performed in atimely manner. All historical data relating to those components, in addition to many other sub-systems, are maintained in these files.
0770 N-16 Meter. Digital Meter replaced with spare unit and calibrated.
0771 PN Photo Eye. Light source for Pneumatic Sample in Reactor was replaced with spareunit.
0772 Primary Demineralizer Pump Seal. The shaft seal of the demineralizer pump wasreplaced due to leakage.
0773 Control Distribution UPS. The UPS was replaced due to failed logic board internal to theUPS.
0774 Pool Liner. A pool leak developed in the pool liner. A leak detection company located theleak and the leak was patched.
0775 T2 Temperature RTD. The insulation for the Pool RTD (T2) failed causing a short andfailed low indication. The unit was replaced with spare unit and calibrated.
0776 Secondary Pump. The secondary pump was replaced with a new unit. This was apredictive maintenance item.
0777 Primary Demineralizer Pump Motor Contactor. The contactor in the motor starter unitfailed. The contactor was replaced.
0778 Reactor Air Compressor Belt. The belt failed and was replaced.
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 1 OCFR50.59evaluation was required. Based on the reviews, none required a 10CFR50.59 evaluation.
The following design changes were made:
0713 Neutron Imaging Facility Modification. Installation of interlock and safety equipment forthe Neutron Imaging Facility.
0720 Reactor ON Sign Modification. Added two Reactor ON and percent power level indicationsigns on the bay floor to inform experimenters of the status of the reactor.
0722 Neutron Diffraction Facility Modification. Installation of interlock and safety equipment forthe Neutron Diffraction Facility.
4
0723 Neutron Imaging Facility Modification. Installation of a RFID proximity reader whichprovides entry permit into the Neutron Imaging Facility.
0728 Secondary Pump Trip. Modification that added automatic secondary pump trip andalarms on low coolant temperature conditions to prevent inadvertent cool-down of thereactor pool water and pool liner.
Document Changes
Procedure changes were reviewed to determine whether or not a 1 OCFR50.59 evaluation wasrequired. Based on the reviews, none required a 10CFR50.59 evaluation.
0714 NRP-XP-102 Neutron Imaging Facility. New procedure for the daily testing and use of theNeutron Imaging Facility.
0715 NRP-OP-104 Reactor Experiments. Added user responsibilities and trainingrequirements for the use of irradiation facilities.
0716 Modification and Maintenance Review.
0717 NRP-OP-105 Response to SCRAMS, Alarms and Abnormal Conditions. Added reactoroperator guidance for the proper response to Neutron Imaging Facility alarms.
0718 Emergency Procedure 2 - Offsite Notification. Updated authentication code list forcalendar year 2011.
0719 NRP-XP-101 Experimental Facilities. New procedure to provide safety and operatinginstructions for experimental facilities.
0721 NRP-XP-103 Neutron Diffraction Facility. New procedure for the daily testing and use of
the Neutron Diffraction Facility.
0724 NRP-XP-102 Neutron Imaging Facility. Changes to procedure to reflect the installation ofthe RFID proximity reader which permits entry into the Neutron Imaging Facility.
0725 NRP-XP-101 Experimental Facilities. Change reflects that instructions regarding theNeutron Diffraction Facility were moved to a separate procedure.
0726 Emergency Procedure :2 - Offsite Notification. Update of American Nuclear Insurerstelephone number per ANI Information Bulletin 11-01.
0727 Emergency Procedure 1 - Emergency Plan Activation, Response, and Actions. Updatedcontact phone numbers on Attachment 8.
0729 NRP-OP-105 Response to SCRAMS, Alarms and Abnormal Conditions.
Test and Experiments
There were no new experiments or changes to existing experiments.
Other Changes
There were no other changes.
5
6.7.4.f Radioactive Effluent:
Liquid Waste (summarized by quarters)
i. Radioactivity Released During the Reporting Period:
Releases to the sanitary sewer are given below:
(1) (2) (3) (4)1 (5)
Period Number of Total Total Diluent Tritium
Batches [tCi Volume LitersLiters01 JAN - 31 MAR 11 2 26.8 5.14 E3 2.80 E3 26.1
2011 1454 pCi of tritium was released during this year.
2011 1465 pCi of total activity was released during this year.
'Based on gross beta activity only. Tritium did not require further dilution.
Releases to unrestricted areas:
Period Total Total Volume TritiumlPCi Liters uCi
01 JUL- 14 JUL 11 3378 1.35 E4 3104
In July 2011 an unaccounted loss of approximately 1.35 E4 liters (3569 gallons) of primary wateroccurred over a period of 14 days. The water loss stopped following the detection and repair of aleak site in the reactor pool liner. It was assumed the water was leaking into the groundsurrounding the reactor site. The radioactivity present in the reactor water met regulatory limits forrelease to unrestricted areas (10 CFR 20 Appendix B Table 2) for the 14 day release.
ii. Identification of Fission and Activation Products:
The gross beta-gamma activity of the batches in (i) above were less than 2x10 5 PCi/ml. Isotopicanalyses of these batches indicated low levels of typical corrosion and activation products. Nofission 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.
6
Gaseous Waste (summarized monthly)
i. Radioactivity Discharged During the Reporting Period (in Curies) for:
(1) Gases:
Year Month Total Time CuriesHours
2011 JANUARY 744 1.367
FEBRUARY 672 2.261
MARCH 744 2.248
APRIL 720 2.467
MAY 744 2.874
JUNE 720 1.749
JULY 744 0.881
AUGUST 744 1.301
SEPTEMBER 720 0.359
OCTC)BER 744 1.112
NOVEMBER 720 0.381
DECEMBER 744 0.658
TOTAL 8760 17.658
(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 a half-life greater than 8 days indicated on any filter duringthis reporting period.
ii. Gases and Particulates Discharged During the Reporting Period:
(1) Gases:
Total activity of Argon-41 released was 17.658 curies in 2011.
The yearly average concentration of Argon-41 released from the PULSTAR reactor facilityexhaust stack in 2011 was 6.6x10-8 pCi/ml. Dose calculations for the year were performed usingmethods given in the Final Safety Analysis Report. Dose calculations gave results less than the10 CFR 20 constraint level of 10 mrem. These results are consistent with environmentalmonitoring data given in Attachment A.
(2) Particulates:
Refer to gaseous waste i.(2) above.
7
Solid Waste from Reactor
i. Total Volume of Solid Waste Packaged
31 ft3 of dry uncompacted waste.
No spent ion exchange resins were disposed.
ii. Total Activity Involved
0.022 mCi of dry uncompacted waste.
No spent ion exchange resins were disposed.
iii. Dates of shipments and disposal
Transfer to the university broad scope radioactive materials license was made on 11 Sep 2011.The University Environmental Health and Safety Center arranges disposal of hazardous wastes.
6.7.4.g Personnel Radiation Exposure Report:
30 individuals were monitored for external radiation dose during the reporting period. Internaldose monitoring was not required for any individual. Collective deep dose-equivalent for 1 Jan2011 to 31 Dec 2011 was 4.791 person-rem. Individual deep dose-equivalent ranged from 0.006rem to 1.259 rem with a median of 0.075 rem.
6.7.4.h Summary of Radiation and Contamination Surveys Within the Facility:
Radiation and contamination surveys performed within the facility 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, thearea or item was confined or decontaminated.
6.7.4.i Description of Environmental Surveys Outside of the Facility:
Refer to Attachment A for results of environmental sampling and analysis.
Radiation surveys performed in unrestricted areas near the reactor facility indicated that:
Radiation was at background levels for most areas (average background is approximately10 prem/h).
Contamination was not detectable.
Net radiation readings ranged from 0 to 50 prem/h while the reactor was operating atpower. However, radiation was at background levels in all routinely occupied spaces.
Water samples from Rocky Branch Creek were analyzed from 14 Jul 2011 to 14 Oct 2011for tritium, gross beta activity, gross alpha activity, and gamma radiation following the lossof primary water. All sample results were consistent with background radioactivity.Environmental monitoring of Rocky Branch Creek is routinely performed in accordancewith facility procedures.
8
ATTACHMENT A
PULSTAR REACTOR
ENVIRONMENTAL. RADIATION SURVEILLANCEREPORT
FOR THE PERIODJANUARY 1, 2011 - DECEMBER 31, 2011
NORTH CAROLINA STATE UNIVERSITY
ENVIRONMENTAL HEALTH AND SAFETYCENTER
RADIATION SAFETY DIVISION
by
Ralton J. HarrisEnvironmental Health Physicist
TABLE OF CONTENTS
1. INTRODUCTION
Table 1 Environmental Monitoring Programs for the PULSTAR Reactor
Table 4.1 Gross Alpha and Beta Activity in Surface Water
Table 4.2 LLD Values for Gamma Emitters in Surface Water
5. VEGETATION
Table 5.1 Gross Beta Activity in Campus Vegetation
Table 5.2 LLD Values for Gamma Emitters in Vegetation
6. THERMOLUMINESCENT DOSIMETERS
Table 6.1 Environmental TLD Exposures
7. QUALITY CONTROL INTERCOMPARISON PROGRAM
Tables 7.1a - 7.1d
8. CONCLUSIONS
APPENDIX I
PAGE NO.
1
2
3
3
4
5-9
10
11
12
13
14
15
16
17
18
19 - 22
23
24 - 28
1. INTRODUCTION
The Environmental Radiation Surveillance Program exists to provide routinemeasurements 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 ForMeasured By Frequency Frequency Measurement
Water from Gross Beta N.E. Prior to Prior to 10 CFR 20Reactor Gross N.E. Discharge Discharge T.S. 6.7.4Facility Gamma N.E. (~ Monthly) - Monthly City of
Vegetation Gross Beta RSD/EHSC Semi- Alternate years NCSUNCSU Gamma RSD/EHSC annually Alternate years NCSUCampus
Milk 1-131 RSD/EHSC Monthly Alternate years NCSULocal Dairy
Abbreviations Used in Table:N.E. = Nuclear Engineering/Reactor Facility; RSD/EHSC = Radiation Safety Division.*These 5 stations include:Withers, Daniels, Broughton, D.H. Hill Library and Environmental Health & Safety Center.+These 8 stations include: the PULSTAR stack, a control station (EHSC) and the 5 airsampling 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 duringthe year. The data shows the normal fluctuations in gross beta activity levels expectedduring the year. Figures 2a through 2e show bar graphs of gross beta activity (fCi/cubicmeter vs. sampling quarters per year). The highest gross beta activity observed was 19.6fCiM 3 at the D.H. Hill Library station during the week of 03/24/11 to 03/31/11. The annualcampus average was 11.4 fCiM -.
Table 2.2 lists LLD values for several gamma emitters which would be indicative offission product activity. No gamma activity due to any of these radionuclides wasdetected.
Table 2.3 lists regulatory limits, alert levels, and average background levels for airborneradioactivity.
TABLE 2.1 LOCATION OF AIR MONITORING STATIONS
SITE
BROUGHTONLIBRARYDANIELSWITHERSEH & S CENTERNORTH HALL
DIRECTION1
SOUTHWESTNORTHWESTSOUTHEASTNORTHEASTWESTNORTHEAST
DISTANCE 2
(meters)125192
9082
1230402
ELEVATION 3
(meters)-17+11
-8-6-3-4
1DIRECTION - DIRECTION FROM REACTOR STACK2 DISTANCE - DISTANCE FROM REACTOR STACK3 ELEVATION - ELEVATION RELATIVE TO THE TOP OF THE REACTOR STACK
3
Table 2.2 Aerially Transported Gamma Activity LLD values fCi/cubic meter
Environmental Health & Safety CenterAirborne Gross Beta Activity
25 Figure 2e
09/23-09/29 12/09-12/1620 2011 2011
.03/24-03/31E 15 2011 05/20-05/262011 2011
10
5
2I-3
0
1 2 3 4
Quarters per Year
TABLE 2.3 REGULATORY LIMITS, ALERT LEVELS, AND BACKGROUND LEVELSFOR AIRBORNE RADIOACTIVITY (fCi M -3).
REGULATORYLIMIT
INVESTIGATIONLEVEL
*AVERAGE N.C.BACKGROUND LEVELNUCLIDE
GROSS BETA 1000
Cs-1 37
Ce-1 34
Nb-95
2 X 105
2 X 105
2X 106
500
100
100
100
100
20
2
0
0
0Zr-95 400
This data represents an average value measured in North Carolina at various locations.Excerpted from 2009 Environmental Surveillance Report produced by the NC Departmentof Environment & Natural Resources Division of Environmental Health Radiation ProtectionSection.
10
3. MILK (TABLE 3.1)
Milk samples are collected in alternate years from the Campus Creamery and the Lake WheelerRoad Dairy and analyzed for 1-131. Data given for 2011 show that no 1-131 activity was detected.
TABLE 3.1A 1-131 IN COW' S MILK (pCi Liter 1 ± 2 (Y) LLD - 2 pCi Liter-
pCi Liter- 1
DATE Campus Creamery Lake Wheeler
<2October 2011 <2
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 itenters (ON) and exits (OFF) the campus. The LLD value for gross alpha and beta activities is - 0.4pCi Liter 1 . For gross alpha activity the Alert Level is 5 pCi Liter-1 and the Regulatory Limit is 15 pCiLiter 1 . For gross beta activity the Alert Level is 5 pCi Liter1 and the Regulatory Limit is 50 pCi Liter1 .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 ofnaturally-occurring radionuclides and none of the gamma emitters listed in Table 4.2 were detected.
TABLE 4.1 GROSS ALPHA AND BETA ACTIVITY IN SURFACE WATER (pCi Liter 1 ± 2r)
LLD, - 0.4 pCi Liter 1 LLDO - 0.4 pCi Liter -1
pCi Liter-1
GROSSALPHADATE
FIRST QUARTER 2011
SECOND QUARTER 2011
THIRD QUARTER 2011
FOURTH QUARTER 2011
LOCATION
ONOFF
ONOFF
ONOFF
ONOFF
< 0.4< 0.4
< 0.4< 0.4
< 0.4< 0.4
< 0.4< 0.4
GROSSBETA
2.8 ± 0.72.5 ± 0.7
3.4 ± 0.73.4 ± 0.7
3.1 +0.72.8+0.7
3.5+0.73.3+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 5.2lists 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 thegamma emitters listed in Table 5.2 were detected.
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 inTable 2.1 and inside the PULSTAR Reactor stack and at North Hall. A control station is located inRoom 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 belowthe dosimeters' minimum measurable quantities (i.e., 1 millirem for gamma radiations and 10 milliremsfor beta radiations) are reported by the contract vendor with the designation "M". The observedreadings 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 thanthose for the other campus stations due to its location inside a concrete penthouse. Pursuant to arecommendation made in the NCSU PULSTAR 2001 Annual Self Assessment, two additional TLDs areincluded at the D.H. Hill Library station to supplement the existing dosimeter. These two additionaldosimeters are a routine part of the quarterly monitoring schedule.
* 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.
The designation "M" is used by the contract vendor for reporting dose equivalents below the minimum measurable quantitywhich is 1 millirem for gamma radiation and 10 millirem for beta radiation
All values reported are Deep DDE
r-_
7. QUALITY CONTROL INTERCOMPARISON PROGRAM
The Environmental Radiation Surveillance Laboratory (ERSL) of the Radiation Safety Division hasanalyzed samples provided by the U.S. DOE Mixed-Analyte Performance Evaluation Program (MAPEPTest Session 24) Radiological and Environmental Sciences Laboratory (RESL) during this reportingperiod. The objective of this program is to provide laboratories performing environmental radiationmeasurements 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 meanof 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 referencevalue may be used to calculate a relative bias:
%Bias = (1 00)(Laboratory Re sult - RESL Re ferenceValue)RESL Re ferenceValue
The relative bias will place the laboratory result in one of three categories:
The typical calculations employed for this program are shown in an example calculation in Appendix 1.
18
I - _.
TABLE 7.1a
GROSS ALPHA & BETA ACTIVITY AIR FILTER--INTERCOMPARISON STUDY01 February 2011
The sample consists of one 50 mm diameter simulated filter spiked with a matrix-free solutioncontaining a single alpha and a single beta emitting nuclide. The reported values and theknown values are given in Bq/filter,.
*NCSU - ENVIRONMENTAL LABORATORY RESULTS
Radionuclide
Gross AlphaGross Beta
*ReportedValue
*ReportedError
MAPEPValue
AcceptanceRange
0.198 - 1.1200.662 - 1.985
0.3961.23
0.0210.03
0.6591.323
19
TABLE 7.1b
MULTINUCLIDE AIR FILTER - INTERCOMPARISON STUDY01 February 2011
The sample consists of one 7 cm diameter glass fiber filter which has been spiked with 0.10gram of solution and dried. The reported values and the known values are given in Bq/filter.
Note: The entry ......"" indicates no analyte was present for purposes of conducting aFalse Positive (+) Test.
20
1,
TABLE 7.1c
MULTINUCLIDE WATER SAMPLE - INTERCOMPARISON STUDY01 February 2011
The sample consists of a spiked aliquot of acidified water (-5 % HNO 3). The reported valuesand the known values are given in Bq/Liter.
*NCSU - ENVIRONMENTAL LABORATORY RESULTS
Radionuclide *ReportedValue
*ReportedEriror
MAPEPValue
Co60Cs137Cs134Co57
Mn54Zn65
24.530.518.2
0.75
33.40.96
1.22.01.00.85
2.11.00
24.629.421.5
31.6
AcceptanceRange
17.2- 32.020.6- 38.215.1- 28.0
False + Test
22.1 - 41.1False + Test
Note: The entry" " indicates no analyte was present for purposes of conducting aFalse Positive (+) Test.
21
TABLE 7.1d
GROSS ALPHA AND BETA WATER SAMPLE - INTERCOMPARISON STUDY01 February 2011
The sample consists of a 5% HNO 3 matrix free solution. The reported values and the knownvalues are given in Bq/Liter.
*NCSU - ENVIRONMENTAL LABORATORY RESULTS
Radionuclide
Gross AlphaGross Beta
*ReportedValue
*ReportedError
MAPEP AcceptanceValue Range
1.623.56
0.080.09
1.1362.96
0.341 - 1.9311.48-4.44
22
* *I b
8. CONCLUSIONS
The data obtained during this period do not show any fission product activities. The observedenvironmental 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 rayinteractions. These facts justify the conclusion that the PULSTAR Reactor facility continues tooperate 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, andthe 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 thestandard 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 readilycompare past analytical performance with present performance. In the example, the normalizedrange equals 0.3 which is less than 3 which is the upper control level. The precision of the resultsis acceptable.
The normalized deviation is calculated by computing the deviation and the standard error of themean, crm. The normalized deviation allows one to measure central tendency (accuracy) readilythrough 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 theupper and lower warning levels. The accuracy of the data is acceptable. Any bias in methodologyor instrumentation may be indicated by these results.
24
F.
EXAMPLE CALCULATIONS
Experimental Data:
Known value = p = 3273 pCi 3H/Liter on September 24, 1974
Expected laboratory precision = a 357 pCi/liter
Sample Result
X, 3060 pCi/liter
X2 3060 pCi/liter
X3 3240 pCi/liter
Mean =x
N
E xi.9360x = ___ 3 3120 pCi/liter
N
where N = number of results = 3
Experimental sigma = s
N.
N (E X.) 2
N i2i
(3060)2+(3060)2+ (3240)2- (3060+3060+32'40)23
s 2
s = 103.9 pCi/liter
Range r
r = lmaximum result - minimum result I
r = 1240 - 30601
r = 180 pCi/liter
25
Range Analysis (RNG ANLY)*
Mean range =
= d2o where d2** = 1.693 for N=3
= (1.693) (357)
R = 604.4 pCi/liter
Control limit = CL
CL = R + 3oR
= D4R where D4** = 2.575 for N = 3
= (2.575) (604.4)
CL = 1556 pCi/liter
Standard error of the range =
GR = (R + 3oR- R)+ 3
= (D4R- R) + 3
= (1556- 604.4) 3
C = 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-R
or x ---------------COR
r-Rtherefore w+x = 1 +x = 1 +
OR
*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
for r • R, x = 0
then r = wR+xoR = wRr
or W =R
rtherefore w+x = w+0 =
Rsince r < R, (180 < 604.4)
180W+X=
604.4
w + x = 0.30
Normalized deviation of the mean from the known value = ND
