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            United States
            Environmental Protection
            Agency
Office of Radiation and Indoor Air
National Air and Radiation
Environmental Laboratory
EPA 402-R-10-001
February 2010
www.epa.gov/narel
            Rapid Radiochemical Methods for Selected
            Radionuclides in Water for Environmental
            Restoration Following Homeland
            Security Events
         228Ra
             **°   30V*
                                                 B&^l

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                                       EPA 402-R-10-001
                                      www.epa.gov/narel
                                          February 2010
                                            Revision 0
      Rapid Radiochemical Methods
   for Selected Radionuclides in Water
for Environmental Restoration Following
        Homeland Security Events
            U.S. Environmental Protection Agency

               Office of Air and Radiation
             Office of Radiation and Indoor Air
       National Air and Radiation Environmental Laboratory
                Montgomery, AL 36115

            Office of Research and Development
         National Homeland Security Research Center
                 Cincinnati, OH 45268

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             Rapid Radiochemical Methods for Selected Radionuclides in Water
This report was prepared for the National Air and Radiation  Environmental Laboratory of the Office of
Radiation and Indoor Air and the National Homeland Security Research Center of the Office of Research
and Development, United States Environmental Protection Agency. It was prepared by Environmental
Management Support, Inc.,  of Silver Spring,  Maryland, under contracts 68-W-03-038, work assignment
43, and EP-W-07-037, work assignments B-41 and 1-41, all managed by David Carman. Mention of trade
names or specific applications does not imply  endorsement or acceptance by EPA.

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              Rapid Radiochemical Methods for Selected Radionuclides in Water
                                        Preface

This compendium provides rapid radioanalytical methods for selected radionuclides in an
aqueous matrix. These new methods were developed to expedite the analytical turnaround time
necessary to prioritize sample processing while providing quantitative results that meet measure-
ment quality objectives applicable to the intermediate and recovery phases of a nuclear or
radiological incident of national significance, such as the detonation of an improvised nuclear
device or a radiological dispersal device. It should be noted that these methods were not
developed for compliance monitoring of drinking water samples, and they should not be
considered as having EPA approval for that or any other regulatory program.

This is the first issue of rapid methods for amercium-241, plutonium-238 and plutonium-
239/240, isotopic uranium, radiostrontium (strontium-90), and radium-226. They have been
single-laboratory validated in accordance with the guidance in Method Validation Guide for
Qualifying Methods Used by Radiological Laboratories Participating in Incident Response
Activities., Validation and Peer Review of U.S. Environmental Protection Agency Radiochemical
Methods of Analysis, and Chapter 6 of Multi-Agency Radiological Laboratory Analytical
Protocols Manual (MARLAP). Depending on the availability of resources, EPA plans to
perform multi-laboratory validations on these methods.

These methods are capable of achieving a required relative method uncertainty of 13% at or
above a default analytical action level based on conservative risk or dose values for the
intermediate and recovery phases. The methods also have been tested to determine the time
within which a batch of samples can be analyzed. For these radionuclides, results for a batch of
samples can be provided within a turnaround time of about 8 to 38 hours instead of the days to
weeks required by some previous methods.

The need to ensure adequate laboratory infrastructure to  support response and recovery actions
following a major radiological incident has been recognized by a number of federal agencies.
The Integrated Consortium of Laboratory Networks (ICLN), created in 2005 by 10 federal
agencies,1 consists of existing laboratory networks across the federal government. The ICLN is
designed to provide a national infrastructure with a coordinated and operational system of
laboratory networks that provide timely, high-quality, and interpretable results for early detection
and effective consequence management of acts of terrorism and other events requiring an
integrated laboratory response. It also designates responsible federal agencies (RFAs) to provide
laboratory support across response phases for chemical, biological, and radiological agents. To
meet its RFA responsibilities for environmental samples, EPA has established the Environmental
Response Laboratory Network (ERLN) to address chemical, biological, and radiological threats.
For radiological agents, EPA is the RFA for monitoring, surveillance, and remediation, and will
share responsibility for overall incident response with the U.S. Department of Energy (DOE). As
part of the ERLN, EPA's Office of Radiation and Indoor Air is leading an initiative to ensure
that sufficient environmental radioanalytical capability and competency exist across a core set of
laboratories to carry out EPA's designated RFA responsibilities.
1 Departments of Agriculture, Commerce, Defense, Energy, Health and Human Services, Homeland Security,
Interior, Justice, and State, and the U.S. Environmental Protection Agency.


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              Rapid Radiochemical Methods for Selected Radionuclides in Water
EPA's responsibilities, as outlined in the National Response Framework, include response and
recovery actions to detect and identify radioactive substances and to coordinate federal
radiological monitoring and assessment activities. This document was developed to provide
guidance to those radioanalytical laboratories that will support EPA's response and recovery
actions following a radiological or nuclear incident of national significance.

As with any technical endeavor, actual radioanalytical projects may require particular methods or
techniques to meet specific measurement quality objectives. Sampling and analysis following a
radiological or nuclear incident will present new challenges in terms of types of matrices, sample
representativeness, and homogeneity not experienced with routine samples. A major factor in
establishing measurement quality objectives is to determine and limit the uncertainties associated
with each aspect of the analytical process.

These methods supplement guidance in a planned series designed to present radioanalytical
laboratory personnel, Incident Commanders (and their designees), and other field response
personnel with key laboratory operational considerations and  likely radioanalytical requirements,
decision paths, and default data quality and measurement quality objectives for samples taken
after a radiological or nuclear incident, including incidents caused by a terrorist attack.
Documents currently completed or in preparation include:

•  Radiological Laboratory Sample Analysis Guide for Incidents of National Significance -
   Radionuclides in Water (EPA 402-R-07-007, January 2008)
•  Radiological Laboratory Sample Analysis Guide for Incidents of National Significance -
   Radionuclides in Air (EPA 402-R-09-007, June 2009)
•  Radiological Laboratory Sample Screening Analysis Guide for Incidents of National
   Significance (EPA 402-R-09-008, June 2009)
•  Method Validation Guide for Qualifying Methods Used by Radiological Laboratories
   Participating in Incident Response Activities (EPA 402-R-09-006, June 2009)
•  Guide for Laboratories — Identification, Preparation, and Implementation of Core
   Operations for Radiological or Nuclear Incident Response (EPA 402-R-10-002, June 2010)
•  A Performance-Based Approach to the Use of Swipe Samples in Response to a Radiological
   or Nuclear Incident (in preparation)
•  Guide for Radiological Laboratories for the Control of Radioactive Contamination and
   Radiation Exposure (in preparation)
•  Radiological Laboratory Sample Analysis Guide for Radiological or Nuclear Incidents -
   Radionuclides in Soil (in preparation)

Comments on this document, or suggestions for future editions, should be addressed to:
Dr. John Griggs
U.S. Environmental Protection Agency
Office of Radiation and Indoor Air
National Air and Radiation Environmental Laboratory
540 South Morris Avenue
Montgomery, AL 36115-2601
(334) 270-3450
Griggs.John@epa.gov
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              Rapid Radiochemical Methods for Selected Radionuclides in Water
                                 Acknowledgments

These methods were developed by the National Air and Radiation Environmental Laboratory
(NAREL) of EPA's Office of Radiation and Indoor Air (ORIA) in cooperation with and funding
from the National Homeland Security Research Center (NHSRC) of the Office of Research and
Development. Dr. John Griggs was the project lead for this document. Several individuals
provided valuable support and input to this document throughout its development. Special
acknowledgment and appreciation are extended to Kathy Hall, of NHSRC. We also wish to
acknowledge the valuable suggestions provided by Cynthia White and her colleagues at Sanford
Cohen & Associates' Southeastern Laboratory and Stephen Workman and his colleagues of
ALS-Paragon Laboratories, who conducted the method-validation studies. Dr. Keith McCroan,
of NAREL, provided significant assistance with the equations used to calculate minimum
detectable concentrations and critical levels. A special thank you is extended to Dan Mackney,
also of NAREL, for his review and comments. Numerous other individuals, both inside and
outside of EPA, provided comments and criticisms of these methods,  and their suggestions
contributed greatly to the quality, consistency, and usefulness of the final methods. Technical
support was provided by Dr. N. Jay Bassin, Dr. Anna Berne, Mr. David Burns, Dr. Carl V.
Gogolak, Dr. Robert Litman, Dr. David McCurdy,  Mr. Robert Shannon, and Ms. M. Leca
Buchan of Environmental Management Support, Inc.
02/23/2010                            iii                                   Revision 0

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              Rapid Radiochemical Methods for Selected Radionuclides in Water
                                     CONTENTS

Acronyms, Abbreviations, Units, and Symbols	v
Radiometric and General Unit Conversions	vii
Americium-241 in Water: Rapid Method for High-Activity Samples	241 Am - Page 1
Plutonium-238 and Plutonium-239/240 in Water: Rapid Method for High-Activity
     Samples	238'239/240Pu - Page 1
Radium-226 in Water: Rapid Method Technique for High-Activity Samples	2226Ra - Page 1
Total Radiostrontium (Sr-90) in Water: Rapid Method for High-Activity Samples ....90Sr - Page 1
Isotopic Uranium in Water: Rapid Method for High-Activity Samples	U-nat - Page 1
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              Rapid Radiochemical Methods for Selected Radionuclides in Water


                   Acronyms, Abbreviations, Units, and Symbols

a	probability of a Type I decision error
AAL	analytical action level
ACS	American Chemical Society
ADL	analytical decision level
APS	analytical protocol specification
ft	probability of a Type II decision error
Bq	becquerel
Ci	curie
cm	centimeter (1CT2 meter)
cpm	counts per minute
cps	counts per second
CRM	certified reference material (see also SRM)
CSU	combined standard uncertainty
d	day
dpm 	disintegrations per minute
DOE 	Department of Energy
dps	disintegrations per second
DRP	discrete radioactive particle
EPA	U.S. Environmental Protection Agency
FWHM	full width at half maximum
g	gram
GPC	gas-flow proportional counter
h	hour
ICP-AES	inductively coupled plasma - atomic emission spectrometry
ICLN	Integrated Consortium of Laboratory Networks
ID	[identifier] [identification number]
ID	inside diameter
IND	improvised nuclear device
keV	kiloelectronvolts (103 electronvolts)
L	liter
LCS	laboratory control sample
m	meter
M	molar
MARLAP	Multi-Agency Radiological Laboratory Analytical Protocols Manual
MDC	minimum detectable concentration
MeV	megaelectronvolts (106 electronvolts)
min	minute
mg	milligram (1CT3 gram)
mL	milliliter (1CT3 liter)
mm	millimeter (1CT3 meter)
MQO	measurement quality obj ective
NAREL	EPA's National Air and Radiation Environmental Laboratory, Montgomery, AL
NHSRC	EPA's National Homeland Security Research Center, Cincinnati, OH
NIST	National  Institute of Standards and Technology
NRC	U.S. Nuclear Regulatory Commission
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              Rapid Radiochemical Methods for Selected Radionuclides in Water


ORIA	U.S. EPA Office of Indoor Air and Radiation
^MR          required relative method uncertainty
pCi	picocurie (1CT9 curie)
PPE	personal protective equipment
ppm	parts per million
QA	quality assurance
QAPP	quality assurance proj ect plan
QC	quality control
RDD	radiological dispersal device
RFA	responsible federal agencies
ROI	region of interest
SDWA	Safe Drinking Water Act
s	second
STS	sample test source
MMR	required method uncertainty
ug 	microgram (!CT6gram)
um 	micrometer (1CT6 meter)
uL 	microliter  (1CT6 liter)
WCS	working calibration source
y	year
02/23/2010                              vi                                     Revision 0

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              Rapid Radiochemical Methods for Selected Radionuclides in Water
                       Radiometric and General Unit Conversions
To Convert
years (y)
disintegrations per
second (dps)
Bq
Bq/kg
Bq/m3
Bq/m3
microcuries per
milliliter (^iCi/mL)
disintegrations per
minute (dpm)
cubic feet (ft3)
gallons (gal)
gray (Gy)
roentgen equivalent
man (rem)
To
seconds (s)
minutes (min)
hours (h)
days (d)
becquerels (Bq)
picocuries (pCi)
pCi/g
pCi/L
Bq/L
pCi/L
(iCi
pCi
cubic meters (m3)
liters (L)
rad
sievert (Sv)
Multiply by
3.16xl07
5.26xl05
8.77xl03
3.65xl02
1
27.0
2.70xl(T2
2.70xl(T2
io-3
109
4.50xlO~7
4.50XKT1
2.83xl(T2
3.78
IO2
io-2
To Convert
s
min
h
d
Bq
pCi
pCi/g
pCi/L
Bq/L
pCi/L
pCi
na
m3
L
rad
Sv
To
y
dps
Bq
Bq/kg
Bq/m3
Bq/m3
(iCi/mL
dpm
ft3
gal
Gy
rem
Multiply by
3.17xl(T8
1.90xl(T6
1.14xl(T4
2.74xl(T3
1
3.70xl(T2
37.0
37.0
IO3
io-9
2.22
2.22xl06
35.3
0.264
io-2
IO2
NOTE: Traditional units are used throughout this document instead of the International System of
Units (SI). Conversion to SI units will be aided by the unit conversions in this table.
02/23/2010
                                       vn
Revision 0

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                                          www.epa.gov
                                         February 2010
                                            Revision 0
     Rapid Radiochemical Method for
          Americium-241 in Water
for Environmental Restoration Following
        Homeland Security Events
            U.S. Environmental Protection Agency

               Office of Air and Radiation
             Office of Radiation and Indoor Air
       National Air and Radiation Environmental Laboratory
                 Montgomery, AL 36115

            Office of Research and Development
         National Homeland Security Research Center
                 Cincinnati, OH 45268

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                              AMERiciUM-241 IN WATER:
                      RAPID METHOD FOR HIGH-ACTIVITY SAMPLES

1.  Scope and Application
   1.1.   The method will be applicable to samples where radioactive contamination is either
         from known or unknown origins. If any filtration of the sample is performed prior to
         starting the analysis, those solids should be analyzed separately. The results from the
         analysis of these solids should be reported separately (as a suspended activity
         concentration for the water volume filtered), but identified with the filtrate results.
   1.2.   The method is specific for 241Am in drinking water and other aqueous samples.
         However, if any isotopes of curium are present in the sample, they will be carried with
         americium during the analytical  separation process and will be observed in the final
         alpha spectrum.
   1.3.   The method uses rapid radiochemical separation techniques for determining americium
         in water samples following a radiological or nuclear incident. Although the method can
         detect concentrations of 241Am on the same order of magnitude as methods used for the
         Safe Drinking Water Act (SDWA), the method is not a substitute for  SDWA-approved
         methods for 241 Am.
   1.4.   The method is capable of achieving a required method uncertainty for 241 Am of 1.9
         pCi/L at an analytical action level of 15 pCi/L. To attain the stated measurement quality
         objectives (MQOs) (see Sections 9.3 and 9.4), a sample volume of approximately 200
         mL and count time of at least 1 hour are recommended. The sample turnaround time
         and throughput may vary based on additional  project MQOs, the  time for analysis of
         the final counting form, and initial sample volume. The method must be validated prior
         to use following the protocols provided in Method Validation Guide for Qualifying
        Methods Used by Radiological Laboratories Participating in Incident Response
        Activities (EPA 2009, reference  16.5).
   1.5.   The method is intended to be used for water samples that are similar in composition to
         drinking water. The rapid 241 Am method was evaluated following the guidance
         presented for "Level E Method Validation: Adapted or Newly Developed Methods,
         Including Rapid Methods" in Method Validation Guide for Qualifying Methods Used
         by Radiological Laboratories Participating in Incident Response Activities (EPA 2009,
         reference 16.5) and Chapter 6 of Multi-Agency Radiological Laboratory Analytical
        Protocols Manual (MARLAP 2004, reference 16.6). The matrix used for the
         determination of 241Am was drinking water from Atlanta, GA. See the appendix for a
         listing of the chemical constituents of the water.
   1.6.   Multi-radionuclide analysis using sequential separation may be possible using this
         method in conjunction with other rapid methods.
   1.7.   The method is applicable to the determination of soluble 241 Am. The method is not
         applicable to the determination of 241Am in highly insoluble particulate  matter possibly
         present in water samples contaminated as a result of a radiological dispersion device
         (ROD) event.

2.  Summary of Method
   2.1.   The method is based on a sequence of two chromatographic extraction resins used to
         concentrate, isolate, and purify americium by  removing interfering  radionuclides as
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                 Americium-241 in Water: Rapid Method for High-Activity Samples
        well as other components of the water matrix in order to prepare the americium fraction
        for counting by alpha spectrometry. The method utilizes vacuum-assisted flow to
        improve the speed of the separations. Prior to the use of the extraction resins, the water
        sample is filtered as necessary to remove any insoluble fractions, equilibrated with
        243Am tracer, and concentrated by evaporation or calcium phosphate precipitation. The
        sample test source (STS) is prepared by microprecipitation with NdF3. Standard
        laboratory protocol for the use of an alpha spectrometer should be used when the
        sample is ready for counting.

3.  Definitions, Abbreviations, and Acronyms
   3.1. Analytical Protocol Specifications (APS). The output of a directed planning process
        that contains the project's analytical data needs and requirements in an organized,
        concise form.
   3.2. Analytical Action Level (AAL). The term "analytical action level" is used to denote the
        value of a quantity that will cause the decisionmaker to choose one of the alternative
        actions.
   3.3. Analytical Decision Level (ADL). The analytical decision level refers to the value that
        is less than the AAL and based on the acceptable error rate and the required method
        uncertainty.
   3.4. Discrete Radioactive Particles (DRPs or Hot Particles). Particulate matter in a sample
        of any matrix where a high concentration of radioactive material is contained in a tiny
        particle (um range).
   3.5. Multi-Agency Radiological Laboratory Analytical Protocols Manual (See Reference
        16.6.).
   3.6. Measurement Quality Objective (MQO). MQOs are the analytical data requirements of
        the data quality objectives and are project- or program-specific. They can be
        quantitative or qualitative. MQOs serve as measurement performance criteria or
        objectives of the analytical  process.
   3.7. Radiological Dispersal Device (ROD), i.e., a "dirty bomb." This is an unconventional
        weapon constructed to distribute radioactive material(s) into the  environment either by
        incorporating them into a conventional bomb or by using sprays, canisters, or manual
        dispersal.
   3.8. Required Method Uncertainty (MMR). The required method uncertainty is a target value
        for the individual measurement uncertainties, and is an estimate of uncertainty (of
        measurement) before the sample is actually measured. The required method uncertainty
        is applicable below an AAL.
   3.9. Required Relative Method Uncertainty (^R). The required relative method uncertainty
        is the WMR divided by the AAL and typically expressed as a percentage. It is applicable
        above the AAL.
   3.10. Sample Test Source (STS). This is the final form of the sample that is used for nuclear
        counting. This form is usually specific for the nuclear counting technique used in the
        method,  such as a solid deposited on a filter for alpha spectrometry analysis.

4.  Interferences
   4.1. Radiological: Alpha-emitting radionuclides with irresolvable alpha energies,  such as
        241 Am (5.48 MeV)), 238Pu (5.50 MeV), and 228Th (5.42 MeV), must be chemically
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                 Americium-241 in Water: Rapid Method for High-Activity Samples
         separated to enable radionuclide-specific measurements. This method separates these
         radionuclides effectively. The significance of peak overlap will be determined by the
         individual detector's alpha energy resolution characteristics and the quality of the final
         precipitate that is counted.
   4.2.  Non-Radiological: Very high levels of competing higher valence anions (greater than
         divalent such as phosphates) will lead to lower yields when using the evaporation
         option due to competition with active sites on the resin. If higher valence anions are
         present, the phosphate precipitation option may need to be used initially in place of
         evaporation. If calcium phosphate coprecipitation is performed to collect americium
         (and other potentially present actinides) from large-volume samples, the amount of
         phosphate added to coprecipitate the actinides (in Step 11.1.4.3) should be reduced to
         accommodate the sample's high phosphate concentration.

5.  Safety
   5.1.  General
         5.1.1.   Refer to your safety manual for concerns of contamination control, personal
                exposure monitoring and radiation dose monitoring.
         5.1.2.   Refer to the laboratory chemical hygiene plan (or equivalent) for general safety
                rules regarding chemicals in the workplace.

   5.2.  Radiological
         5.2.1.   Hot Particles (DRPs)
                5.2.1.1.  Hot particles, also termed "discrete radioactive particles" (DRPs), will
                        be small, on the order of 1 mm or less. Typically, DRPs are not evenly
                        distributed in the media and their radiation emissions are not uniform
                        in all directions (anisotropic). Filtration using a 0.45-um or finer filter
                        will minimize the presence  of these particles.
                5.2.1.2.  Care should be taken to provide suitable  containment for filter media
                        used in the pretreatment of  samples that may have DRPs, because the
                        particles become highly statically charged as they dry out and will
                        "jump" to other surfaces causing contamination.
                5.2.1.3.  Filter media should be individually surveyed for the presence of these
                        particles, and this information should be  reported with the final sample
                        results.
         5.2.2.   For samples with detectable activity  concentrations of this radionuclide, labware
                should be used only once due to  potential for cross contamination.
   5.3.  Procedure-Specific Non-Radiological Hazards
         Particular attention should be paid to the use of hydrofluoric acid (HF). HF is an
         extremely dangerous chemical used in the preparation of some of the reagents and in
         the microprecipitation procedure. Appropriate personal protective equipment (PPE)
         must be used in strict accordance with the laboratory safety program specification.

6.  Equipment and Supplies
   6.1.  Analytical balance with a 0.01-g readability  or better.
   6.2.  Cartridge reservoirs, 10- or 20-mL syringe style with locking device, or equivalent.
   6.3.  Centrifuge able to accommodate 250-mL flasks.
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                 Americium-241 in Water: Rapid Method for High-Activity Samples
   6.4.  Centrifuge flasks, 250-mL capacity.
   6.5.  Filter with 0.45-um membrane.
   6.6.  Filter apparatus with 25-mm-diameter polysulfone filtration chimney, stem support, and
         stainless steel support. A single-use (disposable) filter funnel/filter combination may be
         used, to avoid cross-contamination.
   6.7.  25-mm polypropylene filter, 0.1 -um pore size, or equivalent.
   6.8.  Stainless steel planchets or other sample mounts able to hold the 25 mm filter.
   6.9.  Tweezers.
   6.10. 100-uL pipette or equivalent and appropriate plastic tips.
   6.11. 10-mL plastic culture tubes with caps.
   6.12. Tips, white inner, Eichrom part number AC-1000-IT, or equivalent.
   6.13. Tips, yellow outer, Eichrom part number AC-1000-OT, or equivalent.
   6.14. Vacuum box, such as Eichrom part number AC-24-BOX, or equivalent.
   6.15. Vortex mixer.
   6.16. Vacuum pump or laboratory vacuum system.
   6.17. Miscellaneous laboratory ware, plastic or glass,  250 mL and 350 mL.

7.  Reagents and Standards

   Note: All reagents are American Chemical Society (ACS) reagent grade or equivalent unless otherwise
   specified.

   Note: Unless otherwise indicated, all references to laboratory water should be understood to mean Type I
   Reagent water. All solutions used in microprecipitation should be prepared with water filtered through a
   0.45-um (or better) filter.

   7.1.  Am-243 tracer solution: 6-10 dpm of 243Am per aliquant, activity added known to at
         least 5% (combined standard uncertainty < 5%).
   7.2.  Ammonium hydrogen phosphate (3.2 M): Dissolve 106 g of ammonium hydrogen
         phosphate  ((NH4)2FIPO4) in 200 mL of water, heat gently to dissolve, and dilute to 250
         mL with water.
   7.3.  Ammonium hydroxide (15 M): Concentrated NH4OH, available commercially.
   7.4.  Ammonium thiocyanate indicator (1 M): Dissolve 7.6 g of ammonium thiocyanate
         (NH4SCN) in 90 mL of water and dilute to 100 mL with water. An appropriate quantity
         of sodium thiocyanate (8.1 g) or potassium thiocyanate (9.7 g) may be substituted for
         ammonium thiocyanate.
   7.5.  Ascorbic acid (1 M): Dissolve 17.6 g of ascorbic acid (CeHgOe) in 90 mL of water and
         dilute to 100 mL with water. Prepare weekly.
   7.6.  Calcium nitrate (0.9 M): Dissolve 53 g of calcium nitrate tetrahydrate (Ca(NO3)2'4H2O)
         in 100 mL of water and dilute to 250 mL with water.
   7.7.  Ethanol, 100%: Anhydrous C2H5OH, available commercially.
         7.7.1. Ethanol (-80% v/v): Mix 80 mL 100% ethanol and 20 mL water.
   7.8.  Ferrous sulfamate (0.6 M): Add 57 g of sulfamic acid (NH2SO3H) to 150 mL of water,
         heat to 70°C. Slowly add 7 g of iron powder (<  100 mesh size) while heating and
         stirring with a magnetic stirrer until dissolved (may take as long as two hours). Filter
         the hot solution using a qualitative filter, transfer to flask, and dilute to 200 mL  with
         water. Prepare fresh weekly.
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                 Americium-241 in Water: Rapid Method for High-Activity Samples
   7.9.  Hydrochloric acid (12 M): Concentrated HC1, available commercially.
        7.9.1.  Hydrochloric acid (9 M): Add 750 mL of concentrated HC1 to 100 mL of water
               and dilute to 1 L with water.
        7.9.2.  Hydrochloric acid (4 M): Add 333 mL of concentrated HC1 to 500 mL of water
               and dilute to 1 L with water.
        7.9.3.  Hydrochloric acid (1 M): Add 83 mL of concentrated HC1 to 500 mL of water
               and dilute to 1 L with water.
   7.10. Hydrofluoric acid (28 M): Concentrated HF, available commercially.
        7.10.1. Hydrofluoric acid (0.58 M): Add 20 mL of concentrated HF to 980 mL of
               filtered demineralized water and mix. Store in a plastic bottle.
   7.11. Neodymium standard solution (1000 ug/mL): May be purchased from a supplier of
        standards for atomic spectroscopy.
   7.12. Neodymium carrier solution (0.50 mg/mL): Dilute 10 mL of the neodymium standard
        solution (7.11) to 20.0 mL with filtered demineralized water. This solution is stable.
   7.13. Neodymium fluoride substrate solution (10 |ig/mL): Pipette 5 mL of neodymium
        standard solution (7.11) into a 500-mL plastic bottle. Add 460 mL of 1-M HC1 to the
        plastic bottle. Cap the bottle and shake to mix. Measure 40 mL of concentrated HF in a
        plastic graduated cylinder and add to the bottle. Recap the bottle and shake to mix
        thoroughly.  This solution is stable for up to six  months.
   7.14. Nitric acid (16 M): Concentrated HNO3, available commercially.
        7.14.1. Nitric acid (3 M): Add 191 mL of concentrated HNO3 to 700 mL of water and
               dilute to  1 L with water.
        7.14.2. Nitric acid (2 M): Add 127 mL of concentrated HNO3 to 800 mL of water and
               dilute to  1 L with water.
        7.14.3. Nitric acid (0.5 M): Add 32 mL of concentrated HNO3 to 900 mL of water and
               dilute to  1 L with water.
   7.15. Nitric acid (2M) - sodium nitrite (0.1 M) solution: Add 32 mL  of concentrated HNO3
        (7.14) to 200 mL of water and mix. Dissolve 1.7 g of sodium nitrite (NaNCh) in the
        solution and dilute to 250 mL with water. Prepare fresh daily.
   7.16. Nitric acid (3 M) - aluminum nitrate (l.OM) solution: Dissolve 213 g of anhydrous
        aluminum nitrate (A1(NO3)3) in 700 mL of water. Add 190 mL of concentrated HNO3
        (7.14) and dilute to 1 L with water. An appropriate quantity of aluminum nitrate
        nonahydrate (375 g) may be substituted for anhydrous aluminum nitrate.
   7.17. Phenolphthalein solution: Dissolve 1 g of phenolphthalein in 100 mL 95% isopropyl
        alcohol and  dilute with 100 mL of water.
   7.18. TRU Resin: 2-mL cartridge, 50- to 100-|j,m mesh size, Eichrom part number TR-R50-S
        and TR-R200-S, or equivalent.
   7.19. UTEVA Resin: 2-mL cartridge, 50- to 100-|j,m  mesh size, Eichrom part number UT-
        R50-S and UT-R200-S,  or equivalent.

   Sample Collection, Preservation, and Storage
   8.1.  No sample preservation is required if sample is  delivered to the laboratory within 3
        days of sampling date/time.
   8.2.  If the dissolved concentration of americium is sought, the insoluble fraction  must be
        removed by filtration before preserving with acid.
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                 Americium-241 in Water: Rapid Method for High-Activity Samples
   8.3.  If the sample is to be held for more than 3 days, concentrated HNOs shall be added to
        achieve a pH<2.

9.  Quality Control
   9.1.  Batch quality control results shall be evaluated and meet applicable Analytical Project
        Specifications (APS) prior to release of unqualified data. In the absence of project-
        defined APS or a project-specific quality assurance project plan (QAPP), the quality
        control sample acceptance criteria defined in the laboratory quality manual and
        procedures shall be used to determine acceptable performance for this method.
        9.1.1.  A laboratory control sample (LCS) shall be run with each batch of samples. The
               concentration of the LCS shall be at or near the action level or level of interest
               for the project.
        9.1.2.  One method blank shall be run with each batch of samples. The laboratory
               blank should consist of laboratory water.
        9.1.3.  One laboratory duplicate shall be run with each batch of samples. The
               laboratory duplicate is prepared by removing an aliquant from the original
               sample container.
        9.1.4.  A matrix spike sample may be included as a batch quality control sample if
               there is concern that matrix interferences may compromise chemical yield
               measurements or overall data quality.
   9.2.  The source preparation method should produce a sample test source whose spectrum
        shows the full width at half maximum (FWHM)  of-60-80 keV for each peak in the
        spectrum. Precipitate reprocessing should be considered if this range of FWHM cannot
        be achieved.
   9.3.  This method is capable of achieving a WMR of 1.9 pCi/L at or below an action level of 15
        pCi/L. This may be adjusted in the  event specific MQOs are different.
   9.4.  This method is capable of achieving a ^MR 13% above 15 pCi/L. This may be adjusted if
        the event specific MQOs are different.
   9.5.  This method is capable of achieving a required minimum detectable concentration
        (MDC)of 1.5pCi/L.

10. Calibration and Standardization
   10.1.  Set up the alpha spectrometry system according to the manufacturer's
          recommendations. The energy range of the spectrometry system should at least
          include the region between 3 and 8 MeV.
   10.2.  Calibrate each detector used to count samples according to ASTM Standard Practice
          D7282, Section 18, "Alpha Spectrometry Instrument Calibrations" (see Reference
          16.3).
   10.3.  Continuing Instrument Quality Control Testing shall be performed according to
          ASTM Standard Practice D7282, Sections 20, 21, and 24.

11. Procedure
   11.1.  Water  Sample Preparation
          11.1.1.   As required, filter the 100- to 200-mL sample aliquant through a 0.45-um
                   filter and collect the sample in an appropriate size beaker.
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           11.1.2.   Acidify the sample with concentrated HNOs to a pH of less than 2.0 by
                   adding enough HNOs. This usually requires about 2 mL of HNOs per 1000
                   mL of sample.
           11.1.3.   Add 6-10 dpm of 243Am as atracer, following laboratory protocol.

                   Note: For a sample approximately 100 mL or less, the evaporation option is
                   recommended. Proceed to Step 11.1.5. Otherwise, go to Step 11.1.4.

           11.1.4.   Calcium  phosphate coprecipitation option
                   11.1.4.1.  Add 0.5 mL of 0.9-M Ca(NO3)2 to each beaker. Place each
                             beaker on a hot plate, cover with a watch glass, and heat until
                             boiling.
                   11.1.4.2.  Once the sample boils, take the watch glass off the beaker and
                             lower the heat.
                   11.1.4.3.  Add 2-3 drops of phenolphthalein indicator and 200 |jL of 3.2 M
                             (NH4)2HPO4 solution.
                   11.1.4.4.  Add enough concentrated NH4OH with a squeeze bottle to reach
                             the phenolphthalein end point and form Ca3(PO4)2 precipitate.
                             NH4OH should be added very slowly. Stir the solution with a
                             glass rod. Allow the sample to heat gently to digest the
                             precipitate for another 20-30 minutes.
                   11.1.4.5.  If the sample volume is too large to centrifuge the entire sample,
                             allow precipitate to settle until solution can be decanted (30
                             minutes to 2 hours) and go to Step 11.1.4.7.
                   11.1.4.6.  If the volume is small enough to centrifuge, go to Step 11.1.4.8.
                   11.1.4.7.  Decant supernatant solution and discard to waste.
                   11.1.4.8.  Transfer the precipitate to a 250-mL centrifuge tube, completing
                             the transfer with a few milliliters of water, and centrifuging the
                             precipitate for approximately 10 minutes at 2000 rpm.
                   11.1.4.9.  Decant supernatant solution and discard to waste.
                   11.1.4.10. Wash the precipitate with an amount of water approximately
                             twice the volume of the precipitate. Mix well using a stirring rod,
                             breaking up the precipitate if necessary. Centrifuge for 5-10
                             minutes at 2000 rpm. Discard the supernatant solution.
                   11.1.4.11. Dissolve precipitate in approximately  5 mL concentrated HNOs
                             Transfer solution to a 100-mL beaker. Rinse centrifuge tube with
                             2-3 mL of concentrated HNO3 and transfer to the same beaker.
                             Evaporate solution to dryness and go to Step 11.2.
           11.1.5.   Evaporation option to reduce volume and to digest organic components
                   11.1.5.1.  Evaporate sample to less than 50 mL and transfer to a 100-mL
                             beaker.

                             Note: For some water samples, CaSO4 formation may occur during
                             evaporation. If this occurs, use the Ca3(PO4)2 precipitation option in Step
                             11.1.4.
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                    11.1.5.2.  Gently evaporate the sample to dryness and redissolve in
                              approximately 5 mL of concentrated HNOs.
                    11.1.5.3.  Repeat Step 11.1.5.2 two more times,  evaporate to dryness, and
                              go to Step 11.2.
    11.2.   Actinide Separations Using Eichrom Resins
           11.2.1.   Redissolve Ca3(PO4)2 residue or evaporated water sample
                    11.2.1.1.  Dissolve either residue with 10 mL of 3-M HNO3 - 1.0-M
                              A1(N03)3.

                              Note: An additional 5 mL may be necessary if the residue volume is large.

                    11.2.1.2.  Add 2 mL of 0.6-M ferrous sulfamate to each solution. Swirl to
                              mix.

                              Note: If the additional 5 mL was used to dissolve the sample in Step
                              11.2.1.1, add a total of 3 mL of ferrous sulfamate solution.

                    11.2.1.3.  Add 1 drop of 1 -M ammonium thiocyanate indicator to each
                              sample and mix.

                              Note: The color of the solution turns deep red, due to the presence of
                              soluble ferric thiocyanate complex.

                    11.2.1.4.  Add 1 mL of 1-M ascorbic acid to  each solution, swirling to mix.
                              Wait for 2-3 minutes.

                              Note: The red color should disappear, which indicates reduction of Fe+3
                              to Fe+2. If the red color still persists, then additional ascorbic acid solution
                              has to be added drop-wise with mixing until the red color disappears.

                              Note: If particles are observed suspended in the solution, centrifuge the
                              sample. The supernatant solution will be transferred to the column in
                              Step 11.2.3.1. The precipitates will be discarded.

           11.2.2.   Setup of UTEVA and TRU cartridges in tandem on the vacuum box system

                    Note: Steps 11.2.2.1 to 11.2.2.5 deal with a commercially available filtration system.
                    Other vacuum systems developed by individual laboratories may be substituted here
                    as long as the laboratory has provided guidance to analysts in their use.

                    11.2.2.1.  Place the inner tube rack (supplied with vacuum box) into the
                              vacuum box with the centrifuge tubes in the rack. Fit the lid to
                              the vacuum system box.
                    11.2.2.2.  Place the yellow outer tips into all 24  openings of the lid of the
                              vacuum box. Fit in the inner white tip into each yellow tip.
                    11.2.2.3.  For each sample solution,  fit in a TRU cartridge on to the inner
                              white tip. Ensure the UTEVA cartridge is locked into the top end
                              of the TRU cartridge.
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                   11.2.2.4.  Lock syringe barrels (funnels/reservoirs) to the top end of the
                             UTEVA cartridge.
                   11.2.2.5.  Connect the vacuum pump to the box. Turn the vacuum pump on
                             and ensure proper fitting of the lid.

                             IMPORTANT: The unused openings on the vacuum box should be
                             sealed. Yellow caps (included with the vacuum box) can be used to plug
                             unused white tips to achieve good seal during the separation.

                   11.2.2.6.  Add 5 mL of 3-M HNOs to the funnel to precondition the
                             UTEVA and TRU cartridges.
                   11.2.2.7.  Adjust the vacuum pressure to achieve a flow-rate of ~1 mL/min.

                             IMPORTANT: Unless otherwise specified in the procedure, use a flow
                             rate of ~1 mL/min for load and strip solutions and ~3 mL/min for rinse
                             solutions.

          11.2.3.   Preliminary purification of the americium fraction using UTEVA and TRU
                   resins
                   11.2.3.1.  Transfer each solution from Step 11.2.1.4 into the appropriate
                             funnel by pouring or by using a plastic transfer pipette. Allow
                             solution to pass through both cartridges at  a flow rate of ~1
                             mL/min.
                   11.2.3.2.  Add 5 mL of 3-MHNO3 to each beaker (from Step 11.2.1.4) as a
                             rinse and transfer each solution into the appropriate funnel (the
                             flow rate can be adjusted to ~3 mL/min).
                   11.2.3.3.  Add 5 mL of 3-M HNOs into each funnel as a second column
                             rinse (flow rate ~3 mL/min).
                   11.2.3.4.  Separate UTEVA cartridge from TRU cartridge. Discard
                             UTEVA cartridge and the effluent collected  so far. Place new
                             funnel on the TRU cartridge.
          11.2.4.   Final americium separation using TRU cartridge

                   Note: Steps 11.2.4.1 to 11.2.4.3 may be omitted if the samples are known not to contain
                   plutonium

                   11.2.4.1.  Pipette 5 mL of 2-M HNO3 into each TRU cartridge from Step
                             11.2.3.4. Allow to drain.
                   11.2.4.2.  Pipette 5 mL of 2-M HNO3 - 0.1-M NaNO2 directly into each
                             cartridge, rinsing each cartridge reservoir while adding the 2-M
                             HNO3-0.1-MNaNO2.

                             IMPORTANT: The flow rate for the cartridge should be adjusted to ~1
                             mL/min for this step.

                             Note: Sodium nitrite is used to oxidize any Pu+3  to  Pu+4 and enhance the
                             Pu/Am separation.
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                   11.2.4.3.  Allow the rinse solution to drain through each cartridge.
                   11.2.4.4.  Add 5 mL of 0.5-M HNO3 to each cartridge and allow it to drain.

                             Note: 0.5-M HNO3 is used to lower the nitrate concentration prior to
                             conversion to the chloride system.

                   11.2.4.5.  Discard the  load and rinse solutions to waste.
                   11.2.4.6.  Ensure that  clean, labeled tubes (at least 25-mL capacity) are
                             placed in the tube rack.
                   11.2.4.7.  Add 3 mL of 9-M HC1 to each cartridge to convert to chloride
                             system. Collect eluate.
                   11.2.4.8.  Add 20 mL  of 4-M HC1 to elute americium. Collect eluate in the
                             same tube.
                   11.2.4.9.  Transfer the combined eluates from Steps II.2 A.I and 11.2.4.8
                             to a 50-mL beaker.
                   11.2.4.10. Rinse tube with a few milliliters of water and add to the same
                             beaker.
                   11.2.4.11. Evaporate samples to near dryness.

                   Important: Do not bake the residue.

                   11.2.4.12. Allow the beaker to cool slightly and then add a few drops of
                             concentrated HC1 followed by 1 mL of water.
                   11.2.4.13. Transfer the solution from  Step 11.2.4.12 to a 10-mL plastic
                             culture tube. Wash the original sample vessel twice with 1-mL
                             washes of 1M HC1. Transfer the washings to the culture tube.
                             Mix by gently swirling the solution in the tube.
                   11.2.4.14. Proceed to neodymium fluoride microprecipitation in Step 11.3.
                   11.2.4.15. Discard the  TRU cartridge.

    11.3.  Preparation of the Sample Test Source

          Note: Instructions below describe preparation of a single Sample Test Source. Several STSs can
          be prepared simultaneously if a multi-channel vacuum box (whale apparatus) is available.

          11.3.1.   Add 100 jiL of the neodymium carrier solution to the tube from Step
                   11.2.4.14 with a micropipette. Gently swirl the tube to mix the solution.
          11.3.2.   Add 10 drops (0.5 mL) of concentrated HF to the tube and mix well by
                   gentle swirling.
          11.3.3.   Cap the tube  and place  it in a cold-water bath for at least 30 minutes.
          11.3.4.   Insert the polysulfone filter stem in the 250-mL vacuum flask. Place the
                   stainless steel screen on top of the fitted plastic filter stem.
          11.3.5.   Place a 25-mm polymeric filter face up on the stainless steel screen. Center
                   the  filter on the stainless steel screen support and apply vacuum. Wet the
                   filter with 100% ethanol,  followed by filtered Type I water.
                                  241
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                    Caution: There is no visible difference between the two sides of the filter. If the filter is
                    turned over accidentally, it is recommended that the filter be discarded and a fresh
                    one removed from the container.

           11.3.6.   Lock the filter chimney firmly in place on the filter screen and wash the
                    filter with additional filtered Type I water.
           11.3.7.   Pour 5.0 mL of neodymium substrate solution down the side of the filter
                    chimney, avoiding directing the stream at the filter. When the solution
                    passes through the filter, wait at least 15 seconds before the next step.
           11.3.8.   Repeat Step 11.3.7 with an additional 5.0 mL of the substrate solution.
           11.3.9.   Pour the sample from Stepl 1.3.3  down the side of the filter chimney and
                    allow the vacuum to draw the solution through.
           11.3.10.  Rinse the tube twice with 2 mL of 0.58 M HF, stirring each wash briefly
                    using a vortex mixer, and pouring each wash down the side of the filter
                    chimney.
           11.3.11.  Repeat rinse using 2 mL of filtered Type I water once.
           11.3.12.  Repeat rinse using 2 mL of 80% ethyl alcohol once.

                    Note: Steps 11.3.10 and 11.3.12 were shown to improve the FWHM in the alpha
                    spectrum, providing more consistent peak resolution.

           11.3.13.  Wash any drops remaining on the sides of the chimney  down toward the
                    filter with a few milliliters of 80% ethyl alcohol.

                    Caution: Directing a stream of liquid onto the filter will disturb the distribution of the
                    precipitate on the filter and render the sample unsuitable for a-spectrometry
                    resolution.

           11.3.14.  Without turning off the vacuum, remove the filter chimney.
           11.3.15.  Turn off the vacuum to remove the filter. Di scard the filtrate to waste for
                    future disposal. If the filtrate is to be retained, it should  be placed in a plastic
                    container to avoid dissolution of the glass vessel by dilute HF.
           11.3.16.  Place the filter on a properly labeled mounting disc. Secure with a mounting
                    ring or other device that will render the filter flat for counting.
           11.3.17.  Let the sample air-dry for a few minutes and when dry,  place in a container
                    suitable for transfer and submit for counting.

                    Note: Other methods for STS preparation, such as electroplating or
                    microprecipitation with cerium fluoride, may be used in lieu of the neodymium
                    fluoride microprecipitation, but any such substitution must be  validated as described
                    in Section 1.4.

12. Data Analysis and Calculations
    12.1.   Equation for determination of final result, combined standard uncertainty, and
           radiochemical yield (if requested):

           The activity concentration of an  analyte and its combined standard  uncertainty are
           calculated using the following equations:
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                     VaxRtxDaxIa
            and
                       =        )x                .
                                    2222
                                                  .
                                   V2xR2xD2xI2      a     A2       V2      R2
                                    a     i    a    a         V    t        «         t

            where:
                         =  activity concentration of the analyte at time of count, (pCi/L)
                ^4t       =  activity of the tracer added to the sample aliquant at its reference
                            date/time, (pCi)
                Ra       =  net count rate of the analyte in the defined region of interest (ROI),
                            in counts per second
                Rt       =  net count rate of the tracer in the defined ROI, in counts per second
                Fa       =  volume of the sample aliquant, (L)
                Dt       =  correction factor for decay of the tracer from its reference date and
                            time to the midpoint of the counting period
                Z)a       =  correction factor for decay of the analyte from the time of sample
                            collection (or other reference  time) to the midpoint of the counting
                            period, if required
                /t        =  probability of a emission in the defined ROI per decay of the tracer
                            (Table 17.1)
                /a        =  probability of a emission in the defined ROI per decay of the
                            analyte (Table 17.1)
                uc(ACz)  =  combined standard uncertainty of the activity concentration of the
                            analyte (pCi/L)
                u(Ai)     =  standard uncertainty of the activity of the tracer added to the
                            sample (pCi)
                w(Fa)     =  standard uncertainty of the volume of sample aliquant (L)
                u(Ra)     =  standard uncertainty of the net count rate of the analyte in counts
                            per second
                u(Rt)     =  standard uncertainty of the net count rate of the tracer in counts per
                            second

            Note: The uncertainties of the decay-correction factors and of the probability of decay
            factors are assumed to be negligible.

            Note: The equation for the combined standard uncertainty (uc(ACa)) calculation is arranged
            to eliminate the possibility of dividing by zero if Ra = 0.

            Note: The standard uncertainty of the activity of the tracer added to the sample must reflect
            that associated with the activity of the standard reference material and any other significant
            sources of uncertainty such as those introduced during the preparation of the tracer solution
            (e.g., weighing or dilution factors) and during the process of adding the tracer to the sample.

            Note: The alpha spectrum of americium isotopes should be examined carefully and the ROI
            reset manually, if necessary, to minimize the spillover of 241Am peak into the 243Am peak
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             12.1.1.  The net count rate of an analyte or tracer and its standard uncertainty can
                     be calculated using the following equations:

                                       _ Cx   Cbx

             and
                                           1C +1  Ch  +1
                                                   -  bx
            where:

                Rx     =    net count rate of analyte or tracer, in counts per second
                Cx     =    sample counts in the analyte or the tracer ROI
                4      =    sample count time (s)
                Cbx    =    background counts in the same ROI as for x
                tb      =    background count time (s)
                u(Rx)  =    standard uncertainty of the net count rate of tracer or analyte, in
                            counts per second1

            If the radiochemical yield of the tracer is requested, the yield and its combined
            standard uncertainty can be calculated using the following equations:
                                  RY =

            and
0.037x4
            where:

              RY      =    radiochemical yield of the tracer, expressed as a fraction
              Rt       =    net count rate of the tracer, in counts per second
              At       =    activity of the tracer added to the sample (pCi)
              Dt       =    correction factor for decay of the tracer from its reference date and
                            time to the midpoint of the counting period
              /t        =    probability of a emission in the defined ROI per decay of the tracer
                            (Table 17.1)
              s        =    detector efficiency, expressed as a fraction
              uc(RY)   =    combined standard uncertainty of the radiochemical yield
1 For methods with very low counts, MARLAP Section 19.5.2.2 recommends adding one count each to the gross
counts and the background counts when estimating the uncertainty of the respective net counts. This minimizes
negative bias in the estimate of uncertainty and protects against calculating zero uncertainty when a total of zero
counts are observed for the sample and background.
                                  241
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              u(Ri)    =    standard uncertainty of the net count rate of the tracer, in counts
                            per second
              u(At)    =    standard uncertainty of the activity of the tracer added to the
                            sample (pCi)
              u(s)     =    standard uncertainty of the detector efficiency

             12.1.2.  If the critical level concentration (Sc) or the minimum detectable
                     concentration (MDC) are requested (at an error rate of 5%), they can be
                     calculated using the following equations:2
    S  =
      0.4x  -^-1  +0.677x  1 + ^-  +1.645x
                                                                               AtxDtx It
                                        tsxVaxRtxDax!a
    MDC =
         2.71x
                           + 3.29X
                              txVxRxDxI
                                                          x Dt x It
            where:
              Rba  =
                           background count rate for the analyte in the defined ROI, in counts
                           per second
12.2.   Results Reporting
       12.2. 1 .   The following items should be reported for each result: volume of sample
                used; yield of tracer and its uncertainty; and full width at half maximum
                (FWHM) of each peak used in the analysis.
       12.2.2.   The following conventions should be used for each result:
                12.2.2.1. Result in scientific notation ± combined standard uncertainty.
                12.2.2.2. If solid material was filtered from the solution and analyzed
                        separately, the results of that analysis should be reported separately
                        as pCi/L of the original volume from which the solids were filtered
                        if no other guidance is provided on reporting of results for the
                        solids. For example:
                                1 Am for Sample  12-1-99:
                                 Filtrate Result:            12.8 ± 1.5 pCi/L
                                 Filtered Residue Result:    2.5 ± 0.3 pCi/L
                                  241
 The formulations for the critical level and minimum detectable concentration are based on the Stapleton
Approximation as recommended in MARLAP Section 20A.2.2, Equations 20.54 and 20A.3.2, and Equation 20.74,
respectively. The formulations presented here assume an error rate of a = 0.05, ft = 0.05 (with z\-a = z^ = 1.645),
and d = 0.4. For methods with very low numbers of counts, these expressions provide better estimates than do the
traditional formulas for the critical level and MDC.
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13. Method Performance
   13.1.  Method validation results are to be reported as an attachment.
          13.1.1.  Expected turnaround time per batch of 14 samples plus QC, assuming
                  microprecipitations for the whole batch are performed simultaneously using
                  a vacuum box system:
            13.1.2. For an analysis of a 200-mL sample aliquant, sample preparation and
                  digestion should take 3.5 h.
            13.1.3. Purification and separation of the americium fraction using cartridges and
                  vacuum box system should take 2.5 h.
            13.1.4. Sample evaporation to near dryness should take ~ 30 minutes.
            13.1.5. The last Stepof source preparation takes ~1 h.
            13.1.6. A 1-3 h counting time is sufficient to meet the MQOs listed in 9.3 and 9.4,
                  assuming detector efficiency of 0.2-0.3, and radiochemical yield of at least
                  0.5. Longer counting time may be necessary to meet these MQOs if detector
                  efficiency is lower.
            13.1.7. Data should be ready for reduction between 8.5 and 10.5 h after beginning
                  of analysis.

14.  Pollution Prevention: This method utilizes small volume (2-mL) extraction
     chromatographic resin columns. This approach leads to a significant reduction in the
     volumes of load, rinse and strip solutions, as compared to classical methods using ion
     exchange resins to separate and purify the americium fraction.

15.  Waste Management
     15.1.   Types of waste generated per sample analyzed
            15.1.1. If Ca3(PC>4)2 coprecipitation is performed, approximately 100-1000 mL of
                  decanted solution that is pH neutral are generated.
            15.1.2. Approximately 35 mL of acidic waste from loading and rinsing the two
                  extraction columns are generated.
            15.1.3. Approximately 35 mL of acidic waste from microprecipitation method for
                  source preparation, contains 1 mL of HF and ~ 8 mL ethanol.
            15.1.4. Unless processed further, the UTEVA cartridge may contain isotopes of
                  uranium, neptunium, and thorium, if any of these were present in the sample
                  originally.
            15.1.5. Unless processed further, the TRU cartridge may contain isotopes of
                  plutonium if any of them were present in the sample originally.
     15.2.   Evaluate all waste streams according to disposal requirements by applicable
            regulations.

16.  References
     16.1.   ACW03 VBS, Rev. 1.6, "Americium, Plutonium, and Uranium in Water (with
            Vacuum Box System)," Eichrom Technologies, Inc., Lisle, Illinois (February 2005).
     16.2.   G-03, V. 1 "Microprecipitation Source Preparation for Alpha Spectrometry," HASL-
            300, 28th Edition, (February 1997).
                                 241
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                Americium-241 in Water: Rapid Method for High-Activity Samples
     16.3.   ASTM D7282 "Standard Practice for Set-up, Calibration, and Quality Control of
            Instruments Used for Radioactivity Measurements," ASTM Book of Standards
            11.02, current version, ASTM International, West Conshohocken, PA.
     16.4.   VBS01, Rev.1.3, "Setup and Operation Instructions for Eichrom's Vacuum Box
            System (VBS)," Eichrom Technologies, Inc., Lisle, Illinois (January 2004).
     16.5.   U.S. Environmental Protection Agency (EPA). 2009. Method Validation Guide for
            Radiological Laboratories Participating in Incident Response Activities. Revision
            0. Office of Air and Radiation, Washington, DC. EPA 402-R-09-006, June.
            Available at:  www.epa.gov/narel/incident_guides.html.
     16.6.   Multi-Agency Radiological Laboratory Analytical Protocols Manual (MARLAP).
            2004. EPA 402-B-1304 04-001A, July. Volume I, Chapters 6, 7, 20, Glossary;
            Volume II and Volume III, Appendix G. Available at: www.epa.gov/radiation/
            marlap/index.html.
     16.7.   ASTM Dl 193, "Standard Specification for Reagent Water" ASTM  Book of
            Standards 11.01, current version, ASTM International, West Conshohocken, PA.
                                241
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                Americium-241 in Water: Rapid Method for High-Activity Samples
17. Tables, Diagrams, Flow Charts, and Validation Data
   17.1. Tables [including major radiation emissions from all radionuclides separated]

           Table 17.1 Alpha Particle Energies and Abundances of Importance
                                            [i]
Nuclide
241Am
243Am
Half-Life
(Years)
432.6
7.37xl03
>,
(s")
5.077x10""
2.98xlO~12
Abundance
0.848
0.131
0.0166
0.871
0.112
0.0136
a Energy
(MeV)
5.486
5.443
5.388
5.275
5.233
5.181
[ ]Only the most abundant particle energies and abundances have been noted here.
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                 Americium-241 in Water: Rapid Method for High-Activity Samples
    17.2. Ingrowth Curves and Ingrowth Factors
                               This section intentionally left blank

    17.3. Spectrum from a Processed Sample
     110 •
     100 -
      90
   «  70 -
   I  60 -
      50 •
      40 -
      30 -
      20 •
      10 •
       Am-243
          Am-241
       3011   3311   3611   3911   4211   4511   4811   5111   5411   5711   8011   6311   6611   6911   7211   7511   7811
                                           Energy (keV)
     17.2 Decay Scheme
                       241 Am and 243Am Decay Scheme
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                 Americium-241 in Water: Rapid Method for High-Activity Samples
    17.4. Flowchart
        Sample preparation (Step 11.1)
       1.  Add 243Am tracer
       2.  Digestion or calcium phosphate
          co-precipitation (2—3 hours)
      Preparation for cartridge (Step 11.2.1)
    1. Dissolve phosphate
    2. Add sulfamate, thiocyanate, ascorbic
      acid (5 minutes)
       Set up of UTEVA and TRU cartridges
        in tandem using VBS (Step 11.2.2)
      1. Assembly
      2. Prep with 5 ml 3 M HNO3 @ 1 mL/min
                               Load the cartridge (Step 11.2.3)
                                 Sample: 20 ml @ 1 mL/min
                              Rinse: 5 ml 3 M HNO3 @ 3 mL/min
                                  2nd rinse: 5mL3M HNO3
                                      (~ 25 minutes)
                              Separate cartridges (Step 11.2.3.4)
                                           I
           UTEVA cartridge to waste
               Effluent to waste
                (Step 11.2.3.4)
          TRU cartridge for processing
        Attach fresh funnel to the cartridge
Elapsed
 time
                                                                                          -3.5 hours
 ~6 hours
                Separation scheme and timeline for determination of Am in water samples
                                                Parti
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               Americium-241 in Water: Rapid Method for High-Activity Samples

+
Discard load and rinse
effluents (Step 11. 2. 4. 5)

*
Discard TRU cartridge
(Step 11. 2. 4. 15)
Caution: may contain Pu

*
Discard filtrates and washes
(Step 11. 3. 15)
Convert Pu '3 to PIT" (Steps 11.2.4.1-3)
1 . 5 ml 2 M HNO 3 @ 3 mUmin
2. 5mL2MHN03+0.1 MNaN02@1 m Urn in
3. 5 mL 0.5 M HNO 3 @ 1 m Urn in
	 1 	
1
/

Strip Am+3 from the cartridge (Steps 1 1.2.4.6-14
1 . Add 3 mL 9 M HCI @ 1 m Urn in
2. Add 20 ml 4 M HCI @ 1 mUmin
3. Evaporate eluate and re dissolve
~ 1 hour
I
1
Microprecipitation (Step 11.3)
1 . Add NdF3 carrier and wait 30 min
2. Filter, dry. mount
(1 hour)
|



\
rs^p ifptT]
) riot
A^ present _J



T Count sample test source (STS) "1
LX^__^OM::3hqU[S 	 _sS
6.5 hours hours
-7.5 hours
8.5 to 10.5 hours
              Separation scheme and timeline for determination of 2* Am in water samples
                                          Part 2
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                Americium-241 in Water: Rapid Method for High-Activity Samples
                                            Appendix
Composition of Atlanta Drinking Water Used for this Study
Metals by ICP-AES
Silicon
Aluminum
Barium
Calcium
Iron
Magnesium
Potassium
Sodium
Inorganic Anions
Chloride
Sulfate
Nitrogen, Nitrate (as N)
Carbon Dioxide
Bicarbonate Alkalinity
Carbonate Alkalinity
Radionuclide
Uranium 234, 235, 238
Plutonium 238, 239/240
Americium 24 1
Strontium 90
Radium 226***
Concentration (mg/L)*
3.18
<0.200
0.0133
9.38
<0.100
<0.500
<0.500
<0.500

12.7
15.6
1.19

23.8
<3.00
Concentration (pCi/L)**
<0.01,<0.01,<0.01
<0.02, <0.02
<0.02
<0.3
0.11 ±0.27
-0.30 ±0.45
           Note: Analyses conducted by independent laboratories.
           *   Values below the reporting level are presented as less than (<) values.
               No measurement uncertainty was reported with values greater than the "Reporting
               Level."
           **  Reported values represent the calculated minimum detectable concentration (MDC)
               for the radionuclide(s).
           *** Two samples analyzed.
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                                         www.epa.gov
                                        February 2010
                                           Revision 0
     Rapid Radiochemical Method for
  Plutonium-238 and Plutonium-239/240
                   in Water
for Environmental Restoration Following
        Homeland Security Events
           U.S. Environmental Protection Agency

               Office of Air and Radiation
             Office of Radiation and Indoor Air
       National Air and Radiation Environmental Laboratory
                Montgomery, AL 36115

            Office of Research and Development
         National Homeland Security Research Center
                 Cincinnati, OH 45268

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                  PLUTONIUM-238 AND PLUTONIUM-239/240 IN WATER:
                      RAPID METHOD FOR HIGH-ACTIVITY SAMPLES

1.  Scope and Application
   1.1.   The method will be applicable to samples where contamination is either from known or
         unknown origins. If any filtration of the sample is performed prior to starting the
         analysis, those solids should be analyzed separately. The results from the analysis of
         these solids  should be reported separately (as a suspended activity concentration for the
         water volume filtered),  but identified with the filtrate results.
   1.2.   The method is specific for 238Pu and 239/240Pu in drinking water and other aqueous
         samples.
   1.3.   The method uses rapid radiochemical separation techniques for determining alpha-
         emitting plutonium isotopes in water samples following a nuclear or radiological
         incident. Although the method can detect concentrations of 238Pu and 239/240Pu on the
         same order of magnitude as methods used for the Safe Drinking Water Act (SDWA),
         this method is not a substitute for SDWA-approved methods for isotopic plutonium.
                                             OIQ       Ozin
   1.4.   The method cannot distinguish between  Pu and   Pu and any results are reported as
         the total activity of the two radionuclides.
   1.5.   The method is capable of achieving a required method uncertainty for 238Pu or 239/240pu
         of 1.9 pCi/L at an analytical action level of 15 pCi/L. To attain the stated measurement
         quality objectives (MQOs) (see Sections 9.3 and 9.4), a sample volume of
         approximately 200 mL  and  count time of at least 1 hour are recommended. The sample
         turnaround time and throughput may vary based on additional  project MQOs, the time
         for analysis  of the final counting form and initial  sample volume. The method must be
         validated prior to use following the protocols provided in Method Validation Guide for
         Qualifying Methods Used by Radiological Laboratories Participating in Incident
         Response Activities (EPA 2009,  reference 16.5).
   1.6.   The method is intended to be used for water samples that are similar in composition to
         drinking water. The rapid plutonium method was evaluated following the guidance
         presented for "Level E Method Validation: Adapted or Newly  Developed Methods,
         Including Rapid Methods" in Method Validation  Guide for Qualifying Methods Used
         by Radiological Laboratories Participating in Incident Response Activities (EPA 2009,
         reference 16.5) and Chapter 6 of Multi-Agency Radiological Laboratory Analytical
         Protocols Manual (MARLAP 2004, reference 16.6). The matrix used for the
         determination of plutonium was drinking water from Atlanta, GA. See table in the
                                                                               01£
         appendix for a listing of the chemical constituents of the water. Although only   Pu
         was used, the method is valid for 239/240pu as well, as they are chemically identical and
         there are no differences in the method that would be used to determine these isotopes.
         Note that this method cannot distinguish between 239Pu and 240Pu and only the sum of
         the activities of these two isotopes can be determined.
   1.7.   Multi-radionuclide analysis using sequential separation may be possible using this
         method in conjunction with other rapid methods.
   1.8.   This method is applicable to the determination of soluble plutonium. This method is not
         applicable to the determination of plutonium isotopes contained in highly insoluble
         paniculate matter possibly present in water  samples contaminated as a result of a
         radiological dispersion  device (RDD) or IND event. Solid material filtered from
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         solutions to be analyzed for plutonium should be treated separately by a method that
         can dissolve high-temperature-fired plutonium oxides such as a solid fusion technique.

2.   Summary of Method
    2.1.   This method is based on the sequential use of two chromatographic extraction resins to
         isolate and purify plutonium by removing interfering radionuclides as well as other
         components of the matrix in order to prepare the plutonium fraction for counting by
         alpha spectrometry. The method utilizes vacuum-assisted flow to improve the speed of
         the separations. Prior to using the extraction resins, a water sample is filtered as
         necessary to remove any  insoluble fractions, equilibrated with 242Pu tracer, and
         concentrated by either evaporation or Ca3(PO/t)2 coprecipitation. The sample test source
         (STS) is prepared by microprecipitation with NdF3. Standard laboratory protocol for the
         use of an alpha spectrometer should be used when the sample is ready for counting.

3.   Definitions, Abbreviations and Acronyms
    3.1.   Analytical Protocol Specifications (APS). The output of a directed planning process
         that contains the project's analytical data needs and requirements in  an organized,
         concise form.
    3.2.   Analytical Action Level (AAL). The term "analytical action level" is used to denote the
         value of a quantity that will cause the decisionmaker to choose one of the alternative
         actions.
    3.3.   Analytical Decision Level (ADL). The analytical decision level refers to the value that
         is less than the AAL and  based on the acceptable error rate and the required method
         uncertainty.
    3.4.   Discrete Radioactive Particles (DRPs or "hot particles"). Particulate matter in a sample
         of any matrix where a high concentration of radioactive material is contained in a tiny
         particle (|im range).
    3.5.   Multi-Agency Radiological Analytical Laboratory Protocols Manual (MARL AP) (see
         Reference 16.6.)
    3.6.   Measurement Quality Objective (MQO). MQOs are the analytical data requirements of
         the data quality objectives and are project- or program-specific. They can be
         quantitative or qualitative. MQOs serve as measurement performance criteria or
         objectives of the analytical process.
    3.7.   Radiological Dispersal Device (RDD), i.e., a "dirty bomb." This is an unconventional
         weapon constructed to distribute radioactive material(s) into the environment either by
         incorporating them into a conventional bomb or by using sprays, canisters, or manual
         dispersal.
    3.8.   Required Method Uncertainty (WMR). The required method uncertainty is a target value
         for the individual measurement uncertainties, and is an estimate of uncertainty (of
         measurement) before the  sample is actually measured. The required  method uncertainty
         is applicable below an AAL.
    3.9.   Relative Required Method  Uncertainty (
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     Plutonium-238,239/240 in Water: Rapid Radiochemical Method for High-Activity Samples


   3.10. Sample Test Source (STS). This is the final form of the sample that is used for nuclear
         counting. This form is usually specific for the nuclear counting technique used in the
         method such as a solid deposited on a filter for alpha spectrometry analysis.

4.  Interferences
   4.1.  Radiological: Alpha-emitting radionuclides with irresolvable alpha energies, such as
         238Pu (5.50 MeV), 241Am (5.48 MeV), and 228Th (5.42 MeV), that must be chemically
         separated to enable measurement. This method separates these radionuclides
         effectively. The significance of peak overlap will be determined by the individual
         detector's alpha energy resolution characteristics and the quality of the final precipitate
         that is counted.
   4.2.  Non-Radiological: Very high levels of competing higher valence anions (greater than
         divalent such as phosphates) will lead to lower yields when using the evaporation
         option due to competition with active sites on the resin. If higher valence anions are
         present phosphate, the precipitation may need to be used initially in place of
         evaporation. If calcium phosphate coprecipitation is performed to collect plutonium
         (and other potentially present actinides) from large-volume samples, the amount of
         phosphate added to coprecipitate the actinides (in Step 11.1.4.3) should be reduced to
         accommodate the  sample's high phosphate concentration.

5.  Safety
   5.1.  General
         5.1.1.  Refer to your safety manual for concerns of contamination control, personal
               exposure monitoring, and radiation dose monitoring.
         5.1.2.  Refer to the laboratory chemical hygiene plan (or equivalent) for general safety
               rules regarding chemicals in the workplace.
   5.2.  Radiological
         5.2.1.  Hot particles (DRPs)
               5.2.1.1.  Hot particles, also termed "discrete radioactive particles" (DRPs), will
                        be small, on the order of 1 mm or less. Typically, DRPs are not evenly
                        distributed in the media and their radiation emissions  are not uniform
                        in all directions (anisotropic). Filtration using a 0.45-um or finer filter
                        will minimize the presence of these particles.
               5.2.1.2.  Care should be taken to provide suitable containment for filter media
                        used in the  pretreatment of samples that may have DRPs, because the
                        particles become highly statically charged as they dry out and will
                        "jump" to other surfaces causing contamination.
               5.2.1.3.  Filter media should be individually surveyed for the presence of these
                        particles, and this information should be reported with the final sample
                        results.
         5.2.2.  For samples with detectable activity concentrations of these radionuclides,
               labware should be used only once due to potential for cross contamination.
   5.3.  Procedure-Specific Non-Radiological Hazards: Particular attention should be paid to
         the use of hydrofluoric acid  (HF). HF is an extremely dangerous chemical used in the
         preparation of some of the reagents and in the microprecipitation procedure.
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        Appropriate personal protective equipment (PPE) must be used in strict accordance
        with the laboratory safety program specification.

6.  Equipment and Supplies
   6.1.  Analytical balance with 0.01-g readability, or better.
   6.2.  Cartridge reservoirs, 10- or 20-mL syringe style with locking device, or equivalent.
   6.3.  Centrifuge able to accommodate 250-mL flasks.
   6.4.  Centrifuge flasks, 250-mL capacity.
   6.5.  Filter with 0.45-|im membrane.
   6.6.  Filter apparatus with 25-mm-diameter polysulfone filtration chimney, stem support, and
        stainless steel support. A single-use (disposable) filter funnel/filter combination may be
        used, to avoid cross-contamination.
   6.7.  25-mm polypropylene filter, 0.1-um pore size, or equivalent.
   6.8.  Stainless steel planchets or other sample mounts able to hold the 25-mm filter.
   6.9.  Tweezers.
   6.10. 100-uL pipette or equivalent and appropriate plastic tips.
   6.11. 10-mL plastic culture tubes with caps.
   6.12. Vacuum pump or laboratory vacuum system.
   6.13. Tips, white inner, Eichrom part number AC-1000-IT, or equivalent.
   6.14. Tips, yellow outer, Eichrom part number AC-1000-OT, or equivalent.
   6.15. Vacuum box, such as Eichrom part number AC-24-BOX, or equivalent.
   6.16. Vortex mixer.
   6.17. Miscellaneous laboratory ware of plastic or glass; 250- and 500-mL capacities.

7.  Reagents and Standards

   Note: All reagents are American Chemical Society (ACS) reagent grade or equivalent unless otherwise
   specified.

   Note: Unless otherwise indicated, all references to water should be understood to mean Type I Reagent
   water. All solutions used in microprecipitation should be prepared with water filtered through a 0.45-um
   (or better) filter.

   7.1.  Ammonium hydrogen oxalate (0.1M): Dissolve 6.3 g of oxalic acid (H2C2O4-2H2O)
        and 7.1 g of ammonium oxalate ((NH4)2C2O4-H2O) in 900 mL of water and dilute to 1
        L with water.
   7.2.  Ammonium hydrogen phosphate (3.2 M):  Dissolve 106 g of (NH4)2HPO4 in 200 mL of
        water, heat gently to dissolve and dilute to 250 mL with water.
   7.3.  Ammonium hydroxide: Concentrated NH/tOH, available commercially.
   7.4.  Ammonium thiocyanate indicator (1 M): Dissolve 7.6 g of ammonium thiocyanate
        (NFLSCN) in 90 mL of water  and dilute to 100 mL with water. An appropriate amount
        of sodium thiocyanate (8.1  g) or potassium thiocyanate (9.7 g) may be substituted for
        ammonium thiocyanate.
   7.5.  Ascorbic acid (1  M) - Dissolve 17.6 g of ascorbic acid (CeHgOe) in 90 mL of water and
        dilute to 100 mL with water. Prepare weekly.
   7.6.  Calcium nitrate (0.9M): Dissolve 53 g of calcium nitrate tetrahydrate (Ca(NO3)2'4H2O)
        in 100 mL of water and dilute  to 250 mL with water.
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   7.7.  Ethanol, 100%: Anhydrous C2H5OH, available commercially.
        7.7.1.  Ethanol (-80% v/v): Mix 80 mL 100% ethanol and 20 mL water.
   7.8.  Ferrous sulfamate (0.6M): Add 57 g of sulfamic acid (NH2SO3H) to 150 mL of water,
        heat to 70°C, slowly add 7 g of iron powder (< 100 mesh size) while heating and
        stirring (magnetic stirrer should be used) until dissolved (may take as long as two
        hours). Filter the hot solution (using a qualitative filter), transfer to flask and dilute to
        200 mL with water. Prepare fresh weekly.
   7.9.  Hydrochloric acid (12 M): Concentrated HC1, available commercially.
        7.9.1.  Hydrochloric acid (4 M): Add 333 mL of concentrated HC1 to 500 mL of water
               and dilute to 1 L with water
        7.9.2.  Hydrochloric acid (1 M): Add 83 mL of concentrated HC1 to 500 mL of water
               and dilute with water to 1 L.
        7.9.3.  Hydrochloric acid (9 M): Add 750 mL of concentrated HC1 to 100 mL of water
               and dilute to 1 L with water.
   7.10. Hydrochloric acid (4 M) - hydrofluoric acid (0.1 M): Add 333 mL of concentrated HC1
        and 3.6 mL of concentrated HF to 500 mL of water and dilute to 1 L with water.
        Prepare fresh daily.
   7.11. Hydrofluoric acid (28M): Concentrated HF, available commercially.
        7.11.1. HF (0.58M): Add 20 mL of concentrated HF to 980 mL of filtered
               demineralized water and mix. Store in a plastic bottle.
   7.12. Neodymium standard solution (1000 ug/mL) may be purchased from a supplier of
        standards for atomic spectroscopy.
   7.13. Neodymium carrier solution (0.50 mg/mL): Dilute 10 mL of the neodymium standard
        solution (7.12) to 20.0 mL with filtered demineralized water. This solution is stable.
   7.14. Neodymium fluoride substrate solution (10 jig/mL): Pipette 5 mL of neodymium
        standard solution (7.12) into a 500-mL plastic bottle. Add 460 mL of 1 M HC1 to the
        plastic bottle. Cap the bottle and shake to mix. Measure 40 mL of concentrated HF acid
        in a plastic graduated cylinder and add to the bottle. Recap the bottle and shake to mix
        thoroughly. This solution is stable for up to six months.
   7.15. Nitric acid (16 M): Concentrated HNO3, available commercially.
        7.15.1. Nitric acid (0.5 M): Add 32 mL of concentrated HNO3 to 900 mL of water and
                 dilute to 1 L with water.
        7.15.2. Nitric acid (2 M): Add 127 mL of concentrated HNO3 to 800 mL of water and
                 dilute to 1 L with water.
        7.15.3. Nitric acid (3 M): Add 191 mL of concentrated HNO3 to 700 mL of water and
                 dilute to 1 L with water.
   7.16. Nitric acid (2M) - sodium nitrite (0.1 M) solution: Add 32 mL of concentrated HNO3
        (7.15) to 200 mL of water and mix. Dissolve 1.7 g of sodium nitrite (NaNC^) in the
        solution and dilute to 250 mL with water. Prepare fresh daily.
   7.17. Nitric acid (3 M) - aluminum nitrate (1.0 M) solution: Dissolve 213 g of anhydrous
        aluminum nitrate (A1(NO3)3)  in 700 mL of water, add 190 mL of concentrated HNO3
        (7.15) and dilute to  1 L with water. An appropriate quantity of aluminum nitrate
        nonahydrate (375 g) may be substituted for anhydrous aluminum nitrate.
   7.18. Phenolphthalein solution: Dissolve 1 g phenolphthalein in 100 mL 95% isopropyl
        alcohol and dilute with 100 mL of water.
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   7.19. Plutonium-242 tracer solution - 6-10 dpm of 242Pu per aliquant, activity added known
        to at least 5% (combined standard uncertainty of no more than 5%).

        Note: If it is suspected that 242Pu may be present in the sample, 236Pu tracer would be an acceptable
        substitute.

   7.20. TRU Resin - 2-mL cartridge, 50- to 100-|j,m mesh size, Eichrom part number TR-R50-
        S and TR-R200-S, or equivalent.
   7.21. UTEVA Resin - 2-mL cartridge, 50- to 100-|j,m mesh size, Eichrom part number UT-
        R50-S and UT-R200-S, or equivalent.

8.  Sample Collection, Preservation, and Storage
   8.1.  Samples should be collected in 1-L plastic containers.
   8.2.  No sample perseveration is required if sample is delivered  to the laboratory within 3
        days of sampling date/time.
   8.3.  If the dissolved concentration of plutonium is sought, the insoluble fraction must be
        removed by filtration before preserving with acid.
   8.4.  If the sample is to be held for more than three days, HNOs  shall be added until pH<2.

9.  Quality Control
   9.1.  Batch quality control results shall be evaluated and meet applicable Analytical Project
        Specifications (APS) prior to release of unqualified data. In the absence of project-
        defined APS or a project specific quality assurance project plan (QAPP), the quality
        control sample acceptance criteria defined in the laboratory quality manual  and
        procedures shall be used to determine acceptable performance for this method.
        9.1.1.  A Laboratory Control Sample (LCS) shall be run with each batch of samples.
               The concentration of the LCS should be at or near the action level or level of
               interest for the project.
        9.1.2.  One method blank shall be run with each batch of samples. The laboratory
               blank should consist of laboratory water.
        9.1.3.  One laboratory duplicate shall be run with each batch of samples. The
               laboratory duplicate is prepared by removing an aliquant from the original
               sample container.
        9.1.4.  A matrix spike sample may be included as a batch quality control sample if
               there is concern that matrix interferences may compromise chemical yield
               measurements or overall data quality.
   9.2.  The source preparation method should produce a sample test source that produces a
        spectrum with the full width at half maximum (FWHM) of 50-100 keV for each peak in
        the spectrum. Precipitate reprocessing  should be considered if this range of FWHM
        cannot be achieved.
   9.3.  This method is capable of achieving a UMR of 1.9 pCi/L at or below an action level of 15
        pCi/L. This may be adjusted if the event specific MQOs are different.
   9.4.  This method is capable of achieving a required ^MR of 13% above 15 pCi/L. This may
        be adjusted if the event specific MQOs are different.
   9.5.  This method is capable of achieving a required minimum detectable concentration
        (MDC)of 1.5pCi/L.
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     Plutonium-238, 239/240 in Water: Rapid Radiochemical Method for High-Activity Samples


10. Calibration and Standardization
   10.1. Set up the alpha spectrometry system according to the manufacturer's
         recommendations. The energy range of the spectrometry system should at least include
         the region between 3 and 8 MeV.
   10.2. Calibrate each detector used to count samples according to ASTM Standard Practice
         D7282, Section 18, "Alpha Spectrometry Instrument Calibrations" (see reference 16.3).
   10.3. Continuing Instrument Quality Control Testing shall be performed according to ASTM
         Standard Practice D7282, Sections 20, 21, and 24.

1 1 . Procedure
   11.1. Water Sample Preparation:
         11.1.1. As required, filter the 100-200 mL sample aliquant through a 0.45-|im filter and
               collect the sample in an appropriate size beaker.
         1 1.1.2. Acidify the sample with concentrated HNOs, to a pH of < 2.0 by adding enough
               HNOs. This usually requires about 2  mL of concentrated HNOs per 1000 mL of
               sample.
         1 1.1.3. Add 6-10 dpm of 242Pu as a tracer, following laboratory protocol. The tracer
               should be added right before you are  planning to proceed to Step 1 1 . 1 .4 or
               11.1.5. If the sample solution with the added tracer is not processed right away,
               isotopic exchange may be compromised and the analytical results will be
               incorrect.

               Note: For a sample approximately 100 mL or less, the evaporation option is recommended.
               Proceed to Step 11.1.5. Otherwise go to Step 11.1.4.

         11.1.4. Calcium phosphate coprecipitation option
               11.1.4.1.  Add 0.5 mL of 0.9-M Ca(NO3)2 to each beaker. Place each beaker on
                         a hot plate, cover with a watch glass, and heat until boiling.
               11.1 .4.2.  Once the sample boils, take the watch glass off the beaker and lower
                         the heat.
               11.1.4.3.  Add 2-3 drops of phenolphthalein indicator and 200 \\L  of 3 .2-M
                         (NH4)2HPO4 solution.
               11.1 .4.4.  Add enough concentrated NiLiOH with a squeeze bottle  to reach the
                         phenolphthalein end point and form Ca3(PO4)2 precipitate. NH/tOH
                         should be added very slowly. Stir the solution with a glass rod.
                         Allow the  sample to heat gently to digest the precipitate  for another
                         20-30 minutes.
               11.1 .4.5.  If the sample volume is too large to centrifuge the entire sample,
                         allow precipitate to settle  until solution can be decanted (30 minutes
                         to 2 hours) and go to Step 1 1 . 1 .4.7.
               11.1 .4.6.  If the volume is small enough to centrifuge, go to Step 1  1 . 1 .4.8.
               1 1 . 1 .4.7.  Decant supernatant solution and discard to waste.
               11.1.4.8.  Transfer the precipitate to a 250-mL centrifuge tube (rinsing the
                         original container with a few milliliters of water to complete the
                         precipitate transfer) and centrifuge the precipitate for approximately
                          10 minutes at 2000 rpm.
               11.1 .4.9.  Decant supernatant solution and discard to waste.
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                11.1.4.10. Wash the precipitate with an amount of water approximately twice
                          the volume of the precipitate. Mix well using a stirring rod, breaking
                          up the precipitate if necessary. Centrifuge for 5-10 minutes at 2000
                          rpm. Discard the supernatant solution.
                11.1.4.11. Dissolve precipitate in approximately 5 mL of concentrated HNOs.
                          Transfer solution to a  100-mL beaker. Rinse centrifuge tube with 2-
                          3 mL of concentrated HNOs and transfer to the same beaker.
                          Evaporate solution to dryness and go to Step 11.2.
         11.1.5. Evaporation option to reduce volume and to digest organic components
                11.1.5.1.  Evaporate sample to less than 50 mL and transfer to a 100-mL
                          beaker.

                          Note: For some water samples, CaSO4 formation may occur during
                          evaporation. If this occurs, use the Ca3(PO4)2 precipitation option in Step
                          11.1.4.

                11.1.5.2.  Gently evaporate the sample to dryness and redissolve in
                          approximately 5 mL of concentrated HNOs.
                11.1.5.3.  Repeat Step 11.1.5.2 two more times, evaporate to dryness, and go to
                          Step 11.2.
    11.2. Actinide Separations using Eichrom resins
         11.2.1. Redissolve Ca3(PO/t)2 residue or evaporated water sample:
                11.2.1.1.  Dissolve either residue with 10 mL of 3 M HNO3-1.0 M A1(NO3)3.

                          Note: An additional 5 mL may be necessary if the residue volume is large.

                11.2.1.2.  Add 2 mL of 0.6-M ferrous sulfamate to each solution. Swirl to mix.

                          Note: If the additional 5 mL was used to dissolve the sample in Step  11.2.1.1,
                          add a total of 3 mL of ferrous sulfamate solution.

                11.2.1.3.  Add 1 drop of 1 -M ammonium thiocyanate indicator to each sample
                          and mix.

                          Note: The color of the solution turns deep red due to the formation of a
                          soluble ferric thiocyanate complex.

                11.2.1.4.  Add 1 mL of 1-M ascorbic acid to each solution, swirling to mix.
                          Wait for 2-3 minutes.

                          Note: The red color should disappear, which indicates reduction of Fe+3 to
                          Fe+2. If the red color persists, then additional ascorbic acid solution is added
                          drop-wise with mixing until the red color disappears.

                          Note: If particles are observed suspended in the solution, centrifuge the
                          sample. The supernatant solution will be transferred to the column in Step
                          11.2.3.1. The precipitates will be discarded.

         11.2.2. Set up  of UTEVA and TRU cartridges in tandem on the vacuum box system


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     Plutonium-238,239/240 in Water: Rapid Radiochemical Method for High-Activity Samples
                Note: Steps 11.2.2.1 to 11.2.2.5 deal with a commercially available filtration system. Other
                vacuum systems developed by individual laboratories may be substituted here as long as
                the laboratory has provided guidance to analysts in their use.

                11.2.2.1.   Place the inner tube rack (supplied with vacuum box) into the
                          vacuum box with the centrifuge tubes in the rack. Fit the lid to the
                          vacuum box system.
                11.2.2.2.   Place the yellow outer tips into all 24 openings of the lid of the
                          vacuum box. Fit in the inner white tip into each yellow tip.
                11.2.2.3.   For each sample solution, fit in the TRU cartridge on to the inner
                          white tip. Ensure the UTEVA cartridge is locked to the top end of
                          the TRU cartridge.
                11.2.2.4.   Lock syringe barrels (funnels/reservoirs) to the top end of the
                          UTEVA cartridge.
                11.2.2.5.   Connect the vacuum pump to the box. Turn the vacuum pump on
                          and ensure proper fitting of the lid.

                          IMPORTANT: The unused openings on the vacuum box should be sealed.
                          Yellow caps (included with the vacuum box) can be used to plug unused white
                          tips to achieve good seal during the separation.

                11.2.2.6.   Add 5 mL of 3-M HNO3 to the funnel to precondition the UTEVA
                          and TRU cartridges.
                11.2.2.7.   Adjust the vacuum pressure to achieve a flow-rate of ~1 mL/min.

                          IMPORTANT: Unless otherwise specified in the procedure, use a flow rate of
                          ~ 1 mL/min for load and strip solutions and ~ 3 mL/min for rinse solutions.

         11.2.3. Preliminary purification of the plutonium fraction using UTEVA and TRU
                resins
                11.2.3.1.   Transfer each solution from Step 11.2.1.4 into the appropriate funnel
                          by pouring or by using a plastic transfer pipette. Allow solution to
                          pass through both cartridges at a flow rate  of ~1 mL/min.
                11.2.3.2.   Add 5 mL of 3-MHNO3 to each beaker (from Step 11.2.1.4) as a
                          rinse and transfer each solution into the appropriate funnel  (the flow
                          rate can be adjusted to ~3 mL/min).
                11.2.3.3.   Add 5 mL of 3-M FINOs into each funnel as  second column rinse
                          (flow rate ~3 mL/min).
                11.2.3.4.   Separate UTEVA cartridge from TRU cartridge. Discard UTEVA
                          cartridge and the effluent collected so far. Place new funnel on the
                          TRU cartridge.
         11.2.4. Final plutonium separation using TRU cartridge
                11.2.4.1.   Pipette 5 mL of 2-M HNO3 into each TRU cartridge from Step
                          11.2.3.4. Allow to drain.
                11.2.4.2.   Pipette 5 mL of 2-M HNO3-0.1-M NaNO2 directly into each
                          cartridge, rinsing each cartridge reservoir while adding the 2 M
                          HNO3-0.1-MNaNO2.


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     Plutonium-238,239/240 in Water: Rapid Radiochemical Method for High-Activity Samples
                          IMPORTANT: The flow rate for the cartridge should be adjusted to ~1
                          mL/min for this step.

                          Note: Sodium nitrite is used to oxidize any Pu+3 to Pu+4 and optimize the
                          separation from other trivalent actinides possibly present in the sample.

                11.2.4.3.  Allow the rinse solution to drain through each cartridge.
                11.2.4.4.  Add 5 mL of 0.5-M HNOs to each cartridge and allow it to drain
                          (flow rate left at ~1 mL/min).

                          Note: 0.5 M HNO3 is used to lower the nitrate concentration prior to
                          conversion to the chloride system.

                          Note: Steps 11.2.4.5 and 11.2.4.6 may be omitted if the samples are known not
                          to contain americium.

                11.2.4.5.  Add 3 mL of 9-M HC1 to each cartridge to convert to chloride
                          system.
                11.2.4.6.  Add 20 mL of 4-M HC1 to remove americium.
                11.2.4.7.  Rinse the cartridge with 25 mL of 4-M HC1-0.1-M HF. Discard all
                          the eluates collected so far to waste (for this step, the flow rate can
                          be increased to ~3 mL/min).

                          Note: 4-M HC1 - 0.1-M HF rinse selectively removes any residual Th that
                          may still be present on the TRU cartridge. The plutonium remains on the
                          cartridge.

                11.2.4.8.  Ensure that clean, labeled plastic tubes are placed in the tube rack
                          under each cartridge.
                11.2.4.9.  Add 10 mL of 0.1-M ammonium bioxalate (MLJK^C^) to elute
                          plutonium from each cartridge, reducing the flow rate to ~1 mL/min.
                11.2.4.10. Set plutonium fraction in the plastic tube aside for neodymium
                          fluoride coprecipitation,  Step 11.3.
                11.2.4.11. Discard the TRU cartridge.

    11.3. Preparation of the Sample Test Source

         Note: Instructions below describe preparation of a single Sample Test Source. Several STSs can be
         prepared simultaneously if a multi-channel vacuum box (whale apparatus)  is available.

         11.3.1.   Add 100 jiL of the neodymium carrier solution  to the tube with a
                  micropipette. Gently swirl the tube to mix the solution.
         11.3.2.   Add 1 mL of concentrated HF to the tube and mix well by gentle swirling.
         11.3.3.   Cap the tube and place it in a cold-water bath for at least  30 minutes.
         11.3.4.   Insert the polysulfone filter stem in the 250-mL vacuum flask. Place the
                  stainless steel screen on top of the fitted plastic  filter stem.
                                    238,239/240
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         11.3.5.  Place a 25-mm polymeric filter face up on the stainless steel screen. Center
                 the filter on the stainless steel screen support and apply vacuum. Wet the filter
                 with 100% ethanol, followed by filtered Type I water.

                 Caution: There is no visible difference between the two sides of the filter. If the filter is
                 turned over accidentally, it is recommended that the filter be discarded and a fresh one
                 removed from the box.

         11.3.6.  Lock the filter chimney firmly in place on  the filter screen and wash the filter
                 with additional filtered Type I water.
         11.3.7.  Pour 5.0 mL of neodymium substrate solution down the side of the filter
                 chimney, avoiding directing the stream at the filter. When the solution passes
                 through the filter, wait at least 15 seconds before the next step.
         11.3.8.  Repeat Step  11.3.7 with an additional 5.0 mL of the substrate  solution.
         11.3.9.  Pour the sample from Step 11.3.3 down the side of the filter chimney and
                 allow the vacuum to draw the solution through.
         11.3.10. Rinse the tube twice with 2 mL of 0.58-M  HF, stirring each wash briefly using
                 a vortex mixer, and pouring each wash down the side of the filter chimney.
         11.3.11. Repeat rinse, using 2 mL of filtered Type I water once.
         11.3.12. Repeat rinse using 2 mL of 80% ethyl alcohol once.
         11.3.13. Wash any drops remaining on the sides of the chimney  down toward the filter
                 with a few milliliters of 80% ethyl alcohol.

                 Caution: Directing a stream of liquid onto the filter will disturb the distribution of the
                 precipitate on the filter and render the sample unsuitable for a-spectrometry resolution.

         11.3.14. Without turning off the vacuum, remove the filter chimney.
         11.3.15. Turn off the vacuum to remove the filter. Discard the filtrate to waste for
                 future disposal. If the filtrate is to be retained, it should be placed in a plastic
                 container to avoid dissolution of the glass vessel by dilute HF.
         11.3.16. Place the filter on a properly labeled mounting disc, secure with a mounting
                 ring or  other device that will render the filter flat for counting.
         11.3.17. Let the sample air-dry for a few minutes and when dry, place in a container
                 suitable for transfer and submit for counting.

                 Note: Other methods for STS preparation, such as electroplating or microprecipitation
                 with cerium fluoride, may be used in lieu of the neodymium fluoride microprecipitation,
                 but any  such substitution must be validated as described in Section 1.5

12. Data Analysis and Calculations
   12.1. Equation for determination of final result, combined standard uncertainty and
        radiochemical yield (if required):

        The activity concentration of an analyte and its combined standard uncertainty are
        calculated using  the following equations:
                                   238,239/240
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     Plutonium-238,239/240 in Water: Rapid Radiochemical Method for High-Activity Samples


              _AtxRaxDtxIt

         and
         where:
         ACn      =  activity concentration of the analyte at time of count, in picocuries per liter
                     (pCi/L)
         At       =  activity of the tracer added to the sample aliquant at its reference date/time
                     (pCi)
         RH       =  net count rate of the analyte in the defined region of interest (ROI), in
                     counts per second
         Rt       =  net count rate of the tracer in the defined ROI, in counts per second
         Fa       =  volume of the sample aliquant (L)
         Dt       =  correction factor for decay of the tracer from its reference date and time to
                     the midpoint of the counting period
         Da       =  correction factor for decay of the analyte from the time of sample
                     collection (or other reference time) to the midpoint of the counting period
                     (if required)
         /t        =  probability of a emission in the defined ROI per decay of the tracer (Table
                     17.1)
         /a        =  probability of a emission in the defined ROI per decay of the analyte
                     (Table 17.1)
         uc(ACa)  =  combined standard uncertainty of the activity concentration of the analyte
                     (pCi/L)
         u(At)     =  standard uncertainty of the activity of the tracer added to the sample (pCi)
         w(Fa)     =  standard uncertainty of the volume of sample aliquant (L)
         u(Ra)     =  standard uncertainty of the net count rate of the analyte (s^1)
         u(Rt)     =  standard uncertainty of the net count rate of the tracer (s^1)

         Note: The uncertainties of the decay-correction factors and of the probability of decay
         factors are assumed to be negligible.

         Note: The equation for the combined standard uncertainty (wc(y4Ca)) calculation is arranged to
         eliminate the possibility of dividing by zero if Ra = 0.

         Note: The standard uncertainty of the activity of the tracer added to the sample must reflect that
         associated with the activity of the standard reference material and any other significant sources of
         uncertainty such as those introduced during the preparation of the tracer solution (e.g., weighing
         or dilution factors) and during the process of adding the tracer to the sample.

         12.1.1.     The net count rate of an analyte or tracer and its standard uncertainty are
                    calculated using the following equations:
                                    238,239/240
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     Plutonium-238,239/240 in Water: Rapid Radiochemical Method for High-Activity Samples
         and
                   C  +1  C+l
         where:

            Rx     =     net count rate of analyte or tracer, in counts per second
            Cx     =     sample counts in the analyte or the tracer ROI
            4      =     sample count time (s)
            Cbx    =     background counts in the same ROI as for x
            tb      =     background count time (s)
            u(Rx)  =     standard uncertainty of the net count rate of tracer or analyte, in
                          counts per second1

         If the radiochemical yield of the tracer is requested, the yield and its combined standard
         uncertainty can be calculated using the following equations:


                          RY=	^	
                                0.037x4 xDtx!txs
         and
         where:

            RY      =    radiochemical yield of the tracer, expressed as a fraction
            Rt       =    net count rate of the tracer, in counts per second
            At       =    activity of the tracer added to the sample (pCi)
            Dt       =    correction factor for decay of the tracer from its reference date and
                          time to the midpoint of the counting period
            /t        =    probability of a emission in the defined ROI per decay of the tracer
                          (Table 17.1)
            e        =    detector efficiency, expressed as a fraction
            uc(RY)   =    combined standard uncertainty of the radiochemical yield
            u(Rt)    =    standard uncertainty of the net count rate of the tracer, in counts per
                          second
            u(At)    =    standard uncertainty of the activity of the tracer added to the sample
                          (pCi)
1 For methods with very low counts, MARLAP Section 19.5.2.2 recommends adding one count each to the gross
counts and the background counts when estimating the uncertainty of the respective net counts. This minimizes
negative bias in the estimate of uncertainty and protects against calculating zero uncertainty when a total of zero
counts are observed for the sample and background.


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            u(s)     =     standard uncertainty of the detector efficiency

         12.1.2.    If the critical level concentration (Sc) or the minimum detectable
                   concentration (MDC) are requested (at an error rate of 5%), they can be
                   calculated using the following equations: 2
  s=±
(t "1 ( t
0.4x -^--1 +0.677x 1 + ^-
L u J I **
"I If t ( O
+ 1.645x 1(7?. ^, +0.4)x^-x 1 + ^-
) V ^ I rJJ

x At x Dt x It

                                      tsxVaxRtxDax!a
  MDC = ^
2.71xfl + ^] + 3.29x K./.xfl + ^l
v 'by V v 'by
x ^4t x Z)t x 7t
                            txVxRxDxI
            where:
                       =  background count rate for the analyte in the defined ROI, in counts
                          per second
    12.2. Results Reporting
         12.2.1. The following data should be reported for each result: volume of sample used;
                yield of tracer and its uncertainty; and FWHM of each peak used in the analysis.
         12.2.2. The following conventions should be used for each result:
                12.2.2.1. Result in scientific notation ± combined standard uncertainty.
                12.2.2.2. If solid material was filtered from the solution and analyzed
                         separately, the results of that analysis should be reported separately as
                         pCi/L of the original volume from which the solids were filtered if no
                         other guidance is provided on reporting of results for the solids. For
                         example:
                          239/240Pu for Sample 12-1-99:
                                   Filtrate Result:            12.8 ± 1.5 pCi/L
                                   Filtered Residue Result:     2.5 ± 0.3 pCi/L

13. Method Performance
    13.1. Method validation results are to be reported.
    13.2. Expected turnaround time per batch 14 samples plus QC, assuming microprecipitations
         for the whole batch are performed simultaneously using a vacuum box system:
         13.2.1. For an analysis of a 200 mL sample aliquant, sample preparation and digestion
                should take -3.5 h.
 The formulations for the critical level and minimum detectable concentration are based on the Stapleton
Approximation as recommended in MARLAP Section 20A.2.2, Equations 20.54 and 20A.3.2, and Equation 20.74,
respectively. The formulations presented here assume an error rate of a = 0.05, ft = 0.05 (with z\-a = z^ = 1.645)
and d = 0.4. For methods with very low numbers of counts, these expressions provide better estimates than do the
traditional formulas for the critical level and MDC.
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         13.2.2. Purification and separation of the plutonium fraction using cartridges and
                vacuum box system should take ~2 h.
         13.2.3. The sample test source preparation step takes ~1 h.
         13.2.4. A one-hour counting time should be sufficient to meet the MQOs listed in 9.3
                and 9.4, assuming detector efficiency of 0.2-0.3, and radiochemical yield of at
                least 0.5. A different counting time may be necessary to meet these MQOs if
                any of the relevant parameters are significantly different.
         13.2.5. Data should be ready for reduction -7.5 h after beginning of analysis.

 14. Pollution Prevention: The method utilizes small volume (2 mL) extraction chromatographic
    resin columns. This approach leads to a significant reduction in the volumes of load, rinse
    and strip solutions,  as compared to classical methods using ion exchange resins to separate
    and purify the plutonium fraction.

 15. Waste Management
    15.1. Types of waste generated per sample analyzed
         15.1.1. If Ca3(PC>4)2 coprecipitation is performed, 100-1000 mL of decanted solution
                that is pH neutral will be generated
         15.1.2. Approximately 45 mL of acidic waste from loading and rinsing the two
                extraction columns will be generated. These solutions may contain an unknown
                quantity of 241Am, if this radionuclide was present in the sample originally. If
                the presence of 241Am is suspected, combined eluates from Steps 11.2.4.5 and
                11.2.4.6 should be collected separately from other rinses, to minimize quantity
                of mixed waste generated.
         15.1.3. Approximately 45 mL of acidic waste from the microprecipitation method for
                source preparation will be generated. The waste contains 1 mL of HF and ~  8
                mL of ethanol.
         15.1.4. Unless processed further, the UTEVA cartridge may contain isotopes of
                uranium, neptunium, and thorium, if any of these were present in the sample
                originally.
         15.1.5. TRU cartridge - ready for appropriate disposal.
    15.2. Evaluate all waste streams according to disposal requirements by applicable
         regulations.

16.  References
    16.1. ACW03 VBS, Rev.  1.6, "Americium, Plutonium, and Uranium in Water (with Vacuum
         Box System)," Eichrom Technologies, Inc., Lisle, Illinois (February 2005).
    16.2. G-03, V.I "Microprecipitation Source Preparation for Alpha Spectrometry", HASL-
         300, 28th Edition, (February 1997).
    16.3. ASTM D7282 "Standard Practice for Set-up, Calibration, and Quality Control of
         Instruments Used for Radioactivity Measurements," ASTM Book of Standards 11.02,
         current version, ASTM International, West Conshohocken, PA.
    16.4. VBS01, Rev.1.3, "Setup and Operation Instructions for Eichrom's Vacuum Box
         System (VBS)," Eichrom Technologies, Inc.,  Lisle, Illinois (January 2004).
    16.5. U.S. Environmental Protection Agency (EPA). 2009. Method Validation Guide for
         Radiological Laboratories Participating in Incident Response Activities. Revision 0.
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     Plutonium-238,239/240 in Water: Rapid Radiochemical Method for High-Activity Samples


         Office of Air and Radiation, Washington, DC. EPA 402-R-09-006, June. Available at:
         www.epa.gov/narel/incident_guides.html.
    16.6. Multi-Agency Radiological Laboratory Analytical Protocols Manual (MARLAP).
         2004. EPA 402-B-1304 04-001A, July. Volume I, Chapters 6, 7, 20, Glossary; Volume
         II and Volume III, Appendix G. Available at: www.epa.gov/radiation/marlap/index.
         html.
    16.7. ASTM Dl 193, "Standard Specification for Reagent Water," ASTM Book of Standards
         11.02, current version, ASTM International,  West Conshohocken, PA.

17.  Tables, Diagrams, Flow Charts, and Validation Data
     17.1.   Tables

           Table 17.1 Alpha Particle Energies and Abundances of Importance
Nuclide
238Pu
239/240Pu(Total)[3]
239Pu
240Pu
242pu
Half-Life
(Years)
87.7
2.411xl04
2.411xl04
6.561xl03
3.735xl05
•k
(s")
2.50xl(T10
9.110xl(T13
9.110xl(T13
3.348xl(T12
5.881xl(T14
Abundance'21
0.7091
0.2898
0.9986
0.7077
0.1711
0.1194
0.7280
0.2710
0.7649
0.2348
a Energy
(MeV)
5.499
5.456
(All at same peak)
5.157
5.144
5.105
5.168
5.124
4.902
4.858
[1] Only the most abundant particle energies and abundances have been noted here.
[2] Unless individual plutonium isotopes are present, the alpha emissions for 239/240pu or separately for 238Pu, should
   use an abundance factor of 1.0.
[3] Half-life and 1 are based on 239Pu.

  17.2.  Ingrowth Curves and Ingrowth Factors

                              This section intentionally left blank
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     Plutonium-238,239/240 in Water: Rapid Radiochemical Method for High-Activity Samples
   17.3. Spectrum from a Processed Sample

                                    Plutonium Spectrum
110 •
100 -
90 -
80 -
tn 70 •
§ 60 •
SO -
40 -
30 -
20 -
10 -
0 -
















Pu-2
I
I
!
I

I




12



,
i
pij-2
JPl










19





1
r
I
\

&









u2
1











K

     3023  3323  3523   3923   4223  4523
          4823   5123  S423  $723  6023  6323  6623   6923  7223  7523  7823
                 Energy (teV)
   17.4. Decay Scheme
 2.46x105y
                                  Plutonium Decay Scheme
                        87.7 y      2.41x104 y
7.04x108y
2.34x1 CFy
                                    6.56x103 y
                                3.74x105y
                                                                            4.47x109y
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                                     238,239/240
                   Pu-Page 17
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      Plutonium-238,239/240 in Water: Rapid Radiochemical Method for High-Activity Samples
   17.5. Flow chart
                              Analytical Flow Chart for Plutonium
        Sample preparation (step 11.1)
        1. Add 242Pu tracer
        2. Evaporation or Ca3(PO4)2
           coprecipitation(1-2 hours)
Set up of UTEVA and TRU cartridges
in tandem using vacuum box (step 11.2.2)
1.  Assembly
2.  Prep with 5 ml 3 M HNO3@ 1 mL/min
      Preparation for cartridge (step 11.2.1)
      1.  Dissolve phosphate.
      2.  Add sulfamate, thiocyanate, ascorbic
         acid (5 minutes)
                             Load the cartridge (step 11.2.3)
                             Sample: 20 ml @ 1 mL/min
                             Rinse: 5 ml 3 M HNO3, @ 3 mL/min
                             2nd rinse: 5 ml 3 M HNO3, @ 3 mL/min
                             (-25 minutes)
                             Separate cartridges (step 11.2.3.4)
           UTEVA cartridge to waste
               Effluent to waste
       TRU cartridge for processing
     Attach fresh funnel to the cartridge
Elapsed

Time
                                                                                       3.5 hours
   Separation scheme and timeline for determination of alpha emitting Pu isotopes in water samples
                                               Parti
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                                       238,239/240
    'Pu-Page 18
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      Plutonium-238,239/240 in Water: Rapid Radiochemical Method for High-Activity Samples
  Convert PiT3 to PiT4 (steps 11.2.4.1-4)
  1. 5 ml 2 M HNO3 @ 3 mL/min
  2. 5 ml 2M HN03+0.1 M NaNO2 @ 1 mL/min
  3. 5 ml 0.5 M HNO3 @ 1 mL/min
       Discard effluents to waste
            (Step 11.2.4.7)
       Caution: may contain Am
      Discard TRU cartridge
         (Step 11.2.4.11)
      Strip Am from the cartridge (steps 11.2.4.5-6)
      1.3mL9M HCI@ 1 mL/min
      2. 20mL4MHCI@1 mL/min
      ~ 25 minutes
      	1	
                                Rinse Th from the TRU cartridge (step 11.2.4.7)
                                25mL4MHCI-0.1  m HF
                                @ 3 mL/min
                                ~ 10 minutes
    Strip Pu from the TRU cartridge (step 11.2.4.8-9)
    10 mL 0.1 M ammonium bioxalate
    @ 1 mL/min
    (10min)
Microprecipitation (step 11.3)
1. Add NdF3 carrier and wait 30 min
2. Filter, dry, mount
(1 hour)
      Discard filtrates and washes
            (Step 11.3.16)
                     Count sample test source (STS)
                   I       for at least one hour
5.5 hours
                                                                                           6.5 hours
                                                                                           7.5 hours
  Separation scheme and timeline for determination of alpha emitting Pu isotopes in water samples
                                               Part 2
02/23/2010
                                         238,239/240
            'Pu-Page 19
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     Plutonium-238,239/240 in Water: Rapid Radiochemical Method for High-Activity Samples
                                            Appendix
Table Al - Composition of Atlanta Drinking Water Used for this Study
Metals by ICP-AES
Silicon
Aluminum
Barium
Calcium
Iron
Magnesium
Potassium
Sodium
Inorganic Anions
Chloride
Sulfate
Nitrogen, Nitrate (as N)
Carbon Dioxide
Bicarbonate Alkalinity
Carbonate Alkalinity
Radionuclide
Uranium 234, 235, 238
Plutonium 238, 239/240
Americium 24 1
Strontium 90
Radium 226***
Concentration (mg/L)*
3.18
<0.200
0.0133
9.38
<0.100
<0.500
<0.500
<0.500

12.7
15.6
1.19

23.8
<3.00
Concentration (pCi/L)**
<0.01,<0.01,<0.01
<0.02, <0.02
<0.02
<0.3
0.11 ±0.27
-0.30 ±0.45
           Note: Analyses conducted by independent laboratories.
           *   Values below the reporting level are presented as less than (<) values.
               No measurement uncertainty was reported with values greater than the "Reporting
               Level."
            **  Reported values represent the calculated minimum detectable concentration (MDC)
               for the radionuclide(s).
           *** Two samples analyzed.
02/23/2010
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                                          www.epa.gov
                                          February 2010
                                            Revision 0
     Rapid Radiochemical Method for
            Radiurn-226 in Water
for Environmental Restoration Following
         Homeland Security Events
            U.S. Environmental Protection Agency

                Office of Air and Radiation
             Office of Radiation and Indoor Air
       National Air and Radiation Environmental Laboratory
                 Montgomery, AL 36115

            Office of Research and Development
          National Homeland Security Research Center
                 Cincinnati, OH 45268

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                                 RADiUM-226 IN WATER:
                RAPID METHOD TECHNIQUE FOR HIGH-ACTIVITY SAMPLES

1   Scope and Application
    1.1.  The method will be applicable to samples where contamination is either from known or
         unknown origins. If any filtration of the sample is performed prior to starting the
         analysis, filterable solids should be analyzed separately. The results from the analysis
         of these solids should be reported separately (as a suspended activity concentration for
         the water volume filtered), but identified with the filtrate results.
    1.2.  This method uses rapid radiochemical separations techniques for the isotopic
         determination of 226Ra in water samples following a nuclear or radiological incident.
         Although the method can detect 226Ra concentrations on the same order of magnitude as
         methods used for the Safe Drinking Water Act (SDWA), this method is not a substitute
         for SDWA-approved methods for 226Ra.
    1.3.  The method is specific for 226Ra and uses MnO2 fixed on a resin bed (MnO2 resin) to
         separate radium from interfering radionuclides and matrix constituents with additional
         separation using Diphonix® resin1 to improve selectivity by removing radioactive
         impurities.
    1.4.  The method is capable of satisfying a required method uncertainty for 226Ra of 0.65
         pCi/L at an analytical action level of 5 pCi/L. To attain the stated measurement quality
         objectives (MQOs) (see Sections 9.3, 9.4, and 9.5), a sample volume of approximately
         200 mL and count time of 4 hours are recommended. Application of the method must
         be validated by the laboratory using the protocols provided in Method Validation Guide
        for Qualifying Methods  Used by Radiological Laboratories Participating in Incident
         Response Activities (EPA 2009, reference 16.3). The sample turnaround time and
         throughput may vary based on additional project MQOs, the time for analysis of the
         final counting form and  initial sample volume.
    1.5.  This method is  intended to be used for water samples that are similar in composition to
         drinking water. The rapid 226Ra method was evaluated following the guidance
         presented for "Level E Method Validation: Adapted or Newly Developed Methods,
         Including Rapid Methods" in Method Validation Guide for Qualifying Methods Used
         by Radiological Laboratories Participating in Incident Response Activities (EPA 2009,
         reference 16.3) and Chapter 6 of Multi-Agency Radiological Laboratory Analytical
         Protocols Manual (MARLAP 2004, reference 16.4). The matrix used for the
         determination of 226Ra was drinking water from Atlanta, GA. See Appendix A for a
         listing of the chemical constituents of the water.
    1.6.  Multi-radionuclide analysis using sequential separation techniques may be possible.

2   Summary of Method
                            T? S
    2.1.  A known quantity of  Ra is used as the yield determinant in this analysis. Since the
         source of the suspected contamination may not be known, the sample is initially
         digested using concentrated nitric acid, followed by volume reduction and conversion
         to the chloride salt using concentrated hydrochloric acid. The solution is adjusted to a
1 A polyfunctional cation exchange resin containing diphosphonic and sulfonic acid functional groups bonded to a
polystyrene/divinylbenzene spherical bead. (Available commercially from Eichrom Technologies, LLC, Lisle, IL,
60561).


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          Radium-226 in Water: Rapid Radiochemical Method for High-Activity Samples


        neutral pH and batch equilibrated with MnC>2 resin to separate radium from some
        radioactive and non-radioactive matrix constituents. Further selectivity is achieved
        using a column which contains Diphonix® resin. The radium (including 226Ra) eluted
        from the column is prepared for counting by microprecipitation with BaSO4.
   2.2. Low-level measurements are performed by alpha spectrometry. The activity measured
        in the 226Ra region of interest is corrected for chemical yield based on the observed
        activity of the alpha peak at 7.07 MeV (217At, the third progeny of 225Ra). See Table
        17.1 for a list of alpha particle energies of the radionuclides that potentially may be
        seen in the alpha spectra.

3  Definitions, Abbreviations and Acronyms
   3.1. Analytical Protocol Specifications (APS). The output of a directed planning process
        that contains the project's analytical data needs and requirements in an organized,
        concise form.
   3.2. Analytical Action Level (AAL).  The term "analytical action level" is used to denote the
        value of a quantity that will cause the decisionmaker to choose one of the alternative
        actions.
   3.3. Analytical Decision Level (ADL). The analytical decision level refers to the value that
        is less than the AAL based  on the acceptable error rate and the required method
        uncertainty.
   3.4. Discrete Radioactive Particles (DRPs or Hot Particles). Particulate matter in a sample
        of any matrix where a high concentration of radioactive material is contained in a tiny
        particle (micron range).
   3.5. Multi-Agency Radiological Analytical Laboratory Protocols Manual (MARL AP) (see
        Reference 16.4).
   3.6. Measurement Quality Objective  (MQO). The analytical data requirements of the data
        quality objectives that are project- or program-specific and can be quantitative or
        qualitative. These analytical data requirements serve as measurement performance
        criteria or objectives of the analytical process.
   3.7. Radiological Dispersal Device (RDD), i.e., a "dirty bomb." This is an unconventional
        weapon constructed to distribute radioactive material(s) into the environment either by
        incorporating them into a conventional bomb or by using sprays, canisters, or manual
        dispersal.
   3.8. Required Method Uncertainty (WMR). The required method uncertainty is a target value
        for the individual measurement uncertainties and is an estimate of uncertainty (of
        measurement) before the sample is actually measured. The required method uncertainty
        as an absolute value is applicable at or below an AAL.
   3.9. Relative Required Method  Uncertainty (^MR). The relative required method uncertainty
        is the WMR divided by the AAL and is typically expressed as a percentage. It is
        applicable above the action level.
   3.10. Sample Test Source (STS). This is the final form of the sample that is used for nuclear
        counting.  This  form is usually specific for the nuclear counting technique in the
        method, such as a solid deposited on  a filter for alpha spectrometry analysis.

4  Interferences
   4.1. Radiological:
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          Radium-226 in Water: Rapid Radiochemical Method for High-Activity Samples


         4.1.1.  All radium isotopes in addition to 226Ra are retained on MnC>2, as are thorium
                isotopes. Unless other radium isotopes are present in concentrations greater than
                approximately three times the 226Ra activity concentration, interference from
                other radium alphas will be resolved when using alpha spectrometry. Method
                performance may be compromised if samples contain high levels of radium
                isotopes due to ingrowth of interfering decay progeny. Samples should be pre-
                screened prior to aliquanting and appropriate limits established to control the
                amount of activity potentially present in the aliquant.2
         4.1.2.  Decay progeny from the 225Ra tracer will  continue to ingrow as more time
                elapses between the separation of radium  and the count of the sample.  Delaying
                the count significantly longer than a day may introduce a possible positive bias
                in results near the detection threshold. When MQOs require measurements close
                to detection levels, and coordinating sample processing and counting schedules
                is not conducive to counting the sample within -36 hours of the separation of
                radium, the impact of tracer progeny tailing into the 226Ra may be minimized
                by reducing the activity of the  225Ra tracer that is added to the sample.  This will
                aid in improving the signal-to-noise ratio  for the 226Ra peak by minimizing the
                amount of tailing from higher energy alphas of the 225Ra progeny.
                4.1.2.1.  The amount of 225Ra  added to the samples may be decreased, and the
                        time for ingrowth between separation and counting increased, to
                        ensure that sufficient 225Ac,  221Fr, and 217At are present for yield
                        corrections at the point of the count. Although this detracts from the
                        rapidity  of the method, it does not detract from  the potential for high
                        throughput.
                4.1.2.2.  The size of the sample aliquant can be increased without changing the
                        amount of tracer added.
         4.1.3.  Optimally, a purified 225Ra tracer  solution3 should be used when performing this
                method.
                4.1.3.1.  When using a purified source of 225Ra, the beginning of decay for
                        225Ra is the activity reference date established during standardization
                        of the 225Ra solution.
                4.1.3.2.  When  a purified 225Ra tracer solution is not available, a  solution
                        containing 225Ra in equilibrium with 229Th may be used  as a tracer. In
                        this case, the 225Ra activity is supported only until thorium is  removed
                        using Diphonix® resin during processing of the sample.  When using
                        this variation of the method, the beginning of 225Ra decay is the point
                        when the sample has  passed through the Diphonix® column.

                        NOTE: Recording the point in time of the beginning of 225Ra decay to within Vz
                        hour will introduce a maximum bias of 0.1% for this measurement.
2 For very elevated levels of radium isotopes, it is recommended that laboratories use "The Determination of
Radium-226 and Radium-228 in Drinking Water by Gamma-ray Spectrometry Using HPGE or Ge(Li) Detectors,"
Revision 1.2, December 2004. Available from the Environmental Resources Center, Georgia Institute of
Technology, 620 Cherry Street, Atlanta, GA 30332-0335, USA, Telephone: 404-894-3776.
3 Using a purified 225Ra tracer is the approach recommended for this method. See Appendix B for a method for
purification and standardization of 225Ra tracer from 229Th solution.


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          Radium-226 in Water: Rapid Radiochemical Method for High-Activity Samples


         4.1.4.  Every effort should be made to use the purified 225Ra as a tracer. It is also
                possible to use 225Ra in equilibrium with 229Th, which may be added to each
                sample as a tracer.4 This approach requires complete decontamination of a
                relatively high activity of 229Th by the Diphonix® column later in the method,
                however, since the spectral region of interest (ROI) for 229Th slightly overlaps
                that of 226Ra. Inadequate decontamination of 229Th will lead to high bias in the
                226Ra result especially when the levels of 226Ra in the sample are below 1 pCi/L.
                The spectral region above 226Ra corresponding to 229Th should be monitored as
                a routine measure to identify samples where 229Th interference may impact
                compliance with project MQOs. If problematic levels of 229Th are identified in
                spectra, measures must be taken to address the interference. These might
                include:
                4.1.4.1.  Separating 225Ra from 229Th prior to its use as a tracer. Using purified
                        225Ra tracer is the default approach recommended for running this
                        method since it will completely address any potential for interference
                        by  removing the source of the problem.
                4.1.4.2.  Increasing the sample aliquant size without changing the amount of
                        tracer added will increase analyte signal and reduce the relative impact
                        of the interference to levels that may be amenable with project MQOs.
                4.1.4.3.  The absolute amount of 229Th  added to the samples may be decreased,
                        as long as the time for ingrowth between separation and counting is
                        increased to ensure that sufficient 217At is  present for yield corrections
                        at the point of the count. Although this detracts from the rapidity of the
                        method, it allows more flexibility in the timing of the count and does
                        not detract from the potential for high throughput.
                4.1.4.4.  Developing spill-down factors (peak overlap corrections) to correct for
                        the interference and account for additional uncertainty in the analytical
                        results. This is not a trivial determination and should be validated prior
                        to use.
         4.1.5.  When a solution containing 225Ra in equilibrium with 229Th is used as a tracer,
                thorium is removed later in the processing of the sample. The equilibrium
                between the  225Ra and 229Th is maintained only until the sample is loaded onto
                the Diphonix® column. At this point, thorium and actinium are retained on the
                column and the 225Ra activity in the eluate is  unsupported and begins to decay.
    4.2.  Non-radiological:
         4.2.1.   Low conductivity water (<100 uS cm"1) may cause low-yield issues with some
                samples. This may be partially corrected for by increasing the conductivity with
                calcium standard solution.
         4.2.2.   Concentrations of non-radioactive barium present significantly in excess of the
                amount of barium carrier added for microprecipitation may severely degrade the
                resolution of alpha spectra. The quality  of spectra should be monitored for
                evidence of decreased resolution. A decreased sample size (i.e., smaller) may
4 The single-laboratory validation for this method was performed successfully by adding 225Ra in secular equilibrium
with 229Th tracer. Using purified 225Ra will provide better method performance since it will eliminate any concern
about breakthrough of the high levels of 229Th added to each sample. See Appendix B of this method for a method
for separating (and standardizing) 225Ra tracer from 229Th solution.


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          Radium-226 in Water: Rapid Radiochemical Method for High-Activity Samples


               need to be selected or the barium carrier decreased or m omitted if the presence
               of these interferences leads to unacceptably degraded method performance.
        4.2.3.  High concentrations of non-radioactive calcium, magnesium or strontium in the
               sample may not only overwhelm the ability of the MnO2 resin to effectively
               exchange radium isotopes but also may degrade the alpha spectrometry peaks
               and increase analytical uncertainty. A decreased sample size (i.e., smaller) may
               need to be selected when the presence of these interferences leads to degraded
               method performance. If it is anticipated that these elements or barium (see Step
               4.2.2) are present in  quantities exceeding a small fraction of the mass of calcium
               or barium added in Steps 11.2.3  and 11.1.3, respectively, an analytical
               determination may need to be performed separately so that the interference can
               be accommodated.

5   Safety
    5.1.  General
        5.1.1.  Refer to your safety  manual for concerns of contamination control, personal
               exposure monitoring and radiation dose monitoring.
        5.1.2.  Refer to the laboratory chemical hygiene plan for general chemical safely rules.
    5.2.  Radiological
        5.2.1.  Hot Particles (DRPs)
               5.2.1.1.  Hot particles, also termed "discrete radioactive particles" (DRPs), will
                        be small, on the order of 1  mm or less. Typically, DRPs are not evenly
                        distributed in the media and their radiation emissions are not uniform
                        in all directions (anisotropic). Filtration using a 0.45-um or finer filter
                        will minimize the presence of these particles.
               5.2.1.2.  Care should be taken to provide suitable containment for filter media
                        used in the pretreatment of samples that may have DRPs, because the
                        particles become highly statically charged as they dry out and will
                        "jump" to other surfaces causing contamination.
               5.2.1.3.   Filter media  should be individually surveyed for the presence of these
                        particles, and this information reported with the final sample results.
        5.2.2.  For samples with detectable activity concentrations of these radionuclides,
               labware should be used only once due to the potential for cross contamination.
    5.3.  Procedure-Specific Non-Radiological Hazards:
        5.3.1.  Solutions of 30% H2O2 can rapidly oxidize organic materials and generate
               significant heat. Do not mix large quantities of peroxide solution with solutions
               of organic solvents as the potential for conflagration exists.

6   Equipment and supplies
    6.1.   Alpha  spectrometer calibrated for use  over the range of ~3.5-10 MeV.
    6.2.   Centrifuge tubes, polypropylene, 50 mL, disposable; or equivalent.
    6.3.   Chromatography columns, polypropylene, disposable:
          6.3.1.  1.5 cm ID. x 15 cm, with funnel reservoir; or equivalent.
          6.3.2.  0.8 cm ID. x 4 cm; or equivalent.
    6.4.   Filter stand and filter funnels.
    6.5.   Filter,  0.1 micron, ~25-mm diameter (suitable for microprecipitation).
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          Radium-226 in Water: Rapid Radiochemical Method for High-Activity Samples


    6.6.   Membrane filter, 0.45 micron, ~47-mm diameter.
    6.7.   Vacuum filtration apparatus.
    6.8.   Heat lamp, 250-300 watt, with reflectors mounted -25 cm above the base.
    6.9.   Petri dish or other suitable container for storing sample test sources.
    6.10.  Stainless steel planchets or suitable holders/backing for sample test sources - able to
          accommodate a 25-mm diameter filter.
    6.11.  Glass beaker, 600-mL capacity.
    6.12.  Stirring hot plate.
    6.13.  Magnetic stir bar (optional).
    6.14.  Centrifuge bottle, polypropylene, 250 mL, disposable; or equivalent  (optional).

7  Reagents and Standards

   Note: All reagents are American Chemical Society (ACS) reagent grade or equivalent unless otherwise
   specified.

   Note: Unless otherwise indicated, all references to water should be understood to mean Type I Reagent
   water (ASTM D1193). For microprecipitation, all solutions used in microprecipitation should be
   prepared with water filtered through a 0.45 um (or smaller) filter.

    7.1.   Ammonium sulfate, solid (NH/t^SO/t, available commercially.
    7.2.   Barium carrier (nominally 0.5 mg/mL as Ba2+). May be purchased as an atomic
          absorption standard and diluted, or prepared by dissolving 0.45 g reagent grade
          barium chloride, dihydrate (BaQ2-2H2O) in water and diluting to 500 mL with water.
    7.3.   Bromthymol  blue indicator solution: Dissolve 0.1 g of bromthymol blue in 16 mL of
          0.01 M NaOH. Dilute to 250  mL with water.
    7.4.   Calcium nitrate solution (1000 ppm as calcium). May be purchased as an atomic
          absorption standard and diluted or prepared by dissolving 2.5 g of calcium carbonate
          (CaCOs) in 70 mL of concentrated nitric acid and diluting to 1 L with water.
    7.5.   Diphonix® resin, 100-200-um mesh size [available from Eichrom Technologies,
          Lisle, IL].
    7.6.   Ethanol, reagent 95 % (C2HsOH), available commercially.
    7.7.   Hydrochloric acid (12 M): Concentrated HC1, available commercially.
          7.7.1.  Hydrochloric acid (2M): Add 170 mL of concentrated HC1 to 800 mL of
                 water and dilute to 1.0 L with water.
          7.7.2.  Hydrochloric acid (1M): Add 83 mL of concentrated HC1 to 800 mL of water
                 and dilute to 1.0 L with water.
    7.8.   Hydrogen peroxide, H2O2 (30 % w/w), available commercially.
    7.9.   Isopropanol,  2-propanol, (CsHyOH), available commercially.
          7.9.1.  Isopropanol (2-propanol), 20 % (v/v) in water: Mix 20 mL of isopropanol
                 with 80 mL of water.
    7.10.  Methanol (CH3OH), available commercially.
    7.11.  MnO2 resin, 75-150 |j,m MnO2 particle size on non-functionalized polystyrene resin
          beads of 100-200 mesh [available commercially from Eichrom Technologies, Lisle,
          IL].
    7.12.  MnO2 stripping reagent: Add 2 mL of 30 % H2O2 per 100 mL of 2 M HC1. Prepare
          fresh for each use.
    7.13.  Nitric acid (16 M): Concentrated HNOs, available commercially.


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          Radium-226 in Water: Rapid Radiochemical Method for High-Activity Samples


    7.14.  Sodium hydroxide (1 M): Dissolve 4 g of sodium hydroxide (NaOH) in 50 mL of
          water and dilute the solution to 100 mL.
    7.15.  Ra-225 tracer in 1-M HC1 solution in a concentration amenable to accurate addition
          of about 180 dpm per sample (generally about 150-600 dpm/mL).
          7.15.1.  Ra-225 may be purified and standardized using a 229Th / 225Ra generator as
                  described in Appendix B of this method.
          7.15.2.  Th-229 containing an equilibrium concentration of 225Ra has been
                                                               T? S
                  successfully used without prior separation of the   Ra. However, this
                  approach may be problematic due to the risk of high result bias (see
                  discussion in Steps 4.1.4 - 4.1.5).

8  Sample Collection, Preservation and Storage
   8.1.     Samples  should be collected in 1-L plastic containers.
   8.2.     No sample preservation is required if sample analysis is initiated within 3 days of
           sampling date/time.
   8.3.     If the sample is to be held for more than three days, HNO3 shall be added until the
           solution pH is less than 2.0.
   8.4.     If the dissolved concentration of radium is sought, the insoluble fraction must be
           removed by filtration before preserving with acid.

9  Quality Control
   9.1.     Batch quality control results shall be evaluated and meet applicable Analytical
           Project Specifications (APS) prior to release of unqualified data. In the absence of
           project-defined APS or a project-specific quality assurance project plan (QAPP), the
           quality control sample acceptance criteria defined in the laboratory quality manual
           and procedures shall be used to determine acceptable performance for this method.
            9.1.1. A laboratory control sample (LCS) shall be run with each batch of samples.
                  The concentration of the LCS should be at or near the action level or a level
                  of interest for the project.
            9.1.2. One method blank shall be run with each batch of samples. The laboratory
                  blank should consist of demineralized water.
            9.1.3. One laboratory duplicate shall be run with each batch of samples. The
                  laboratory  duplicate is prepared by removing an aliquant from the original
                  sample container.
            9.1.4. A matrix spike sample may be included as a batch quality control sample if
                  there is concern  that matrix interferences, such as the presence of elemental
                  barium in the sample, may compromise chemical yield measurements, or
                  overall data quality.
    9.2.    Sample-specific quality control measures
            9.2.1. Limits and evaluation criteria shall be established to monitor each alpha
                  spectrum to ensure that spectral resolution and peak separation is adequate
                  to provide  quantitative results. When 229Th / 225Ra solution is added directly
                  to the sample, the presence of detectable counts between -5.0 MeV and the
                                                   T7£\
                  upper boundary  established for the   Ra ROI generally  indicates the
                             T7Q                         00^
                  presence of   Th in the sample, and in the   Ra ROI. If the presence of
                  229Th is noted and the concentration of 226Ra is determined to be an order of
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          Radium-226 in Water: Rapid Radiochemical Method for High-Activity Samples


                   magnitude below the action limit or the detection threshold of the method,
                   take corrective actions to ensure that MQOs have not been compromised
                   (e.g., clean-up 225Ra tracer before adding, or re-process affected samples and
                   associated QC samples. See interferences sections Steps 4.1.4 - 4.1.5. for
                   discussion).
    9.3.   This method is capable of achieving a MMR of 0.65 pCi/L at or below an action level of
          5.0 pCi/L.  This may be adjusted in the event specific MQOs are different.
    9.4.   This method is capable of achieving a ^MR 13% above 5 pCi/L. This may be adjusted
          if the event specific MQOs are different.
    9.5.   This method is capable of achieving a required minimum detectable concentration
          (MDC)of l.OpCi/L.

10 Calibration and Standardization
   10.1.  Set up, operate, calibrate and perform quality control for alpha spectrometry units in
          accordance with the laboratory's quality manual and standard operating procedures
          and consistent with ASTM Standard Practice D7282, Sections 7-13, 18, and 24 (see
          reference 16.5).

           Note: The calibrated energy range for the alpha spectrometer for this method should be from
           -3.5 to 10 MeV

   10.2.  If 225Ra is separated and purified from 229Th for use as a tracer, the activity reference
          date established during standardization of the tracer is used as the 225Ra activity
          reference date (see Appendix B of this method).
   10.3.  When using 229Th containing an equilibrium concentration of 225Ra, the time of most
          recent separation / purification of the 229Th standard solution must be known in order
          to determine the extent of secular equilibrium between 229Th and its 225Ra progeny.
          Verify the  date of purification by examining the Certificate of Analysis, or other
          applicable documentation, for the standard.
   10.4.  When using 229Th containing an equilibrium concentration of 225Ra, 225Ra is separated
          from its 229Th parent as the solution passes through the Diphonix column. This is the
          beginning of 225Ra decay and the date and time used for decay correction of the
          tracer.
          10.4.1.   If the purification date of the 229Th is not documented, at least 100 days must
                                                                      OOQ
                   have elapsed between separation and use to ensure that    Th, and its
                   progeny 225Ra are in full secular equilibrium (i.e., >99%. See Table 17.3).

11 Procedure
   11.1.  Initial Sample Treatment
          11.1.1.   For each sample in the batch, aliquant 0.2 L of raw or filtered water into a
                   beaker.

                   Note: Smaller or larger aliquants may be used if elevated sample activity is present or
                   as needed to meet detection requirements or MQOs. Method validation must be
                   conducted using approximately the same volume as that to be used in sample analysis^
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           11.1.2.  To each aliquant, add 10 mL of concentrated nitric acid per 100 mL of
                   sample.
           11.1.3.  To each sample aliquant, add 100 uL of 0.5 mg/mL (nominal) barium carrier
                   solution and approximately 180 dpm of 225Ra tracer solution. The initial
                   amount of 225Ra added as a tracer should be high enough so that the
                   resultant counting uncertainty of the 217At activity ingrown from the tracer is
                   five  percent (5 %) or less during the allotted sample count time.

                   Note: The activity of 217At present at the midpoint of the count is used to calculate the
                   chemical yield for radium by back-calculating the activity of 225Ra recovered. The
                   initial amount of 225Ra added as tracer may need to be varied to accommodate
                   planned differences in the time that will elapsed between chemical separation and the
                   count, but the activity should be sufficient, and the count time long enough, to ensure
                   that the resultant counting uncertainty for the 217At peak is five (5 %) percent or less.
                   See the calculation for At, in Step 12.2 for calculation of ingrowth factor for 217At and
                   Table 17.2 for typical ingrowth factors for a series of ingrowth times.

           11.1.4.  Reduce the sample volume to -20% of the original volume by bringing the
                   solution to a gentle boil and evaporating.
           11.1.5.  Following this digestion, add 10 mL of concentrated hydrochloric acid, and
                   carefully evaporate the solution to incipient dryness.
           11.1.6.  Reconstitute the sample by adding 100 mL of 1-M HC1. The sample may be
                   gently  heated if necessary to facilitate dissolution of residual  salts.
    11.2. Water Sample Preparation and Pre-concentration of Radium on MnO2  resin:
           11.2.1.  Add 100 mL of 1-MNaOHto each sample.
           11.2.2.  If particulate material is visible at this time, filter the sample through a 0.45-
                   |im filter.  (Do not rinse the filter). The filter should be saved for possible
                   analysis for DRPs.
           11.2.3.  Add enough 1000 ppm calcium solution to the filtrate from Step  11.2.2 to
                   ensure that the final calcium concentration is about 10 ppm. For waters that
                   naturally have calcium in them above 10 ppm this step will be unnecessary.
           11.2.4.  Add a  few drops of bromthymol blue indicator solution and adjust each
                   sample to neutral pH by carefully adding 1-M NaOH until the color changes
                   from yellow to blue-green.

                   Note: Adding too much base will overshoot the blue-green endpoint (indicated by blue
                   color). The amount of NaOH added in Step 11.2.4 may be adjusted by carefully
                   adding  a small quantity of 1-M HC1 and 1-M NaOH as needed to reach a blue-green
                   endpoint.

           11.2.5.  The  sample is equilibrated with -1.0 g MnO2 resin for 0.5-1.5 hours. Two
                   options are provided:
                   11.2.5.1. Option 1: Add -1.0 g MnO2 resin to a beaker containing the
                            neutralized sample. Cover with a watch glass and stir on a
                            magnetic stirrer for at least 30 minutes.
                   11.2.5.2. Option 2: Transfer the neutralized sample to a 250 mL centrifuge
                            bottle which contains -1.0 g MnO2 resin. Agitate the bottle gently
                            on a shaker or in a tumbler for at least 30 minutes.
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          Radium-226 in Water: Rapid Radiochemical Method for High-Activity Samples

                            Note: Two options are provided for contacting the sample with MnO2 resin.
                            The contact time noted above (30 minutes) is to be understood as a
                            minimum. Higher radium yields may be obtained with somewhat longer
                            contact times (up to 90 minutes). Excessive agitation of the resin may lead
                            to abrasion and loss of some MnO2 from the resin and result in degraded
                            chemical yields. Although sample quantitation is not significantly impacted
                            since a 225Ra yield tracer is used, uptake on the resin during this step should
                            be reasonably optimized by evaluating the process and time used and
                            choosing a default optimal conditions corresponding to a minimum of 80-
                            85% uptake from a clean water matrix.

           11.2.6.  Pour the suspension into a 1.5-cm ID. x 15-cm column fitted with a
                   reservoir funnel. Allow sample to pass through column. Rinse the walls of
                   the funnel reservoir and column with demineralized water. The combined
                   column effluent from this step may be discarded.
           11.2.7.  Place a clean 50 mL centrifuge tube under each MnC>2 column. Add 10 mL
                   of freshly made MnC>2 Stripping Reagent to the MnC>2 column to elute
                   radium and other elements. Catch the column eluate containing radium and
                   retain for subsequent processing.

                   Note: Effervescence will be noted upon addition of the MnO2 Stripping Reagent.
                   Gently tapping the column to dislodge any bubbles that form will help minimize
                   channeling and may improve radium recovery. The resin bed will become light yellow
                   in color as MnO2 dissolves.

    11.3.   Actinium and Thorium Removal Using Diphonix® resin:
            11.3.1. Prepare a Diphonix® resin column for each sample to be processed as
                   follows:5
                   11.3.1.1. Slurry  -1.0 gram Diphonix® resin per column in water.
                   11.3.1.2. Transfer the resin to the 0.8-cm ID. x 4-cm columns to  obtain a
                            uniform resin bed of-1.4-1.6 mL (bed height -26-30 mm). A top
                            column barrier (e.g., frit, glass wool, beads) may be used to
                            minimize turbulence that may disrupt the resin bed when adding
                            solution to the column.
            11.3.2. Precondition the column by passing 20 mL of 2-M HC1 through the column
                   discarding the column effluent.
            11.3.3. Place a clean 50-mL centrifuge tube under each Diphonix® column.
            11.3.4. Swirl the solution retained in Step 11.2.7 to remove bubbles and carefully
                   load onto the column taking care to minimize disturbing the resin bed.
                   Collect column effluents in the 50-mL centrifuge tube. Allow the solution to
                   flow by gravity.
            11.3.5. When the load solution has stopped flowing (or is below the top of the resin
                   bed), rinse the column with two 5-mL volumes of 2-M HC1. Collect the
                   rinse solutions in the same 50-mL centrifuge tube (the total volume will be
                   approximately 20 mL).
5 Commercially supplied pre-packed columns may be used here. When packing columns using bulk resin, excessive
resin fines should be removed by rinsing the resin one or more times with an excess of water and decanting the
water containing the fines prior to transferring the material to the column.
                                      226
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            11.3.6. Record the date and time of the last rinse (Step 11.3.5) as the date and time
                   of separation of radium from parent and progeny. This is also the beginning
                   of ingrowth of 225Ac (and 221Fr and 217At).

                   Note: If purified 225Ra tracer is added to the sample (see Step 10.2 and Appendix B),
                   the 225Ra activity was unsupported before the tracer solution was added to the sample.
                   The activity reference date and time established during standardization of the 225Ra
                   tracer is used as the reference date for the 225Ra solution.

                   Note: If 225Ra at some degree of secular equilibrium with 229Th is added as tracer in
                   the initial step, the activity of 225Ra is dependent upon the total amount of time
                   between the last 229Th purification and Stepll.3.6. The decay of 225Ra starts at Step
                   11.3.6.
                                    ®
                   Note: The Diphonix  resin contains thorium, actinium and possibly other
                   radionuclides present in the sample and should be disposed of according to applicable
                   laboratory procedures.

    11.4. Barium sulfate micro-precipitation of 226Ra
          11.4.1.  Add ~3.0 g of (NH4)2SO4 to the 20 mL of 2M HC1 solution collected from
                   the Diphonix® column in Steps 11.3.3  - 11.3.5.  Mix gently to completely
                   dissolve the salt (dissolves readily).
          11.4.2.  Add 5.0 mL of isopropanol and mix gently (to avoid generating bubbles).
          11.4.3.  Place in an ultrasonic bath filled with cold  tap water (ice may be added) for
                   at least 20 minutes.
          11.4.4.  Pre-wet a 0.1-micron filter using methanol or ethanol. Filter the suspension
                   through the filter using vacuum. The precipitate will not be visually
                   apparent.
          11.4.5.  Rinse the sample container and filter apparatus with three 2-mL portions of
                   20% isopropanol solution to dissolve residual (NH4)2SO4. Allow each rinse
                   to completely pass  through filter before adding the subsequent rinse.
          11.4.6.  Rinse the filter apparatus with about 2 mL  of methanol or ethanol to
                   facilitate drying. Turn off vacuum.
          11.4.7.  Carefully remove the filter and place it face-side up in a Petri dish. Carefully
                   dry under a heating lamp for few minutes.  Avoid excessive heat which may
                   cause the filter to curl or shrink.
          11.4.8.  Mount the dried filter on a support appropriate for the counting system to be
                   used.
          11.4.9.  Store the filter for at least 24 hours to allow sufficient 217At (third progeny
                   of 225Ra) to ingrow into the sample test source allowing a measurement
                   uncertainty for the 217At of < ~5 %.
          11.4.10. Count by alpha spectrometry. The count times should be adjusted to meet
                   the uncertainties and detection capabilities identified in Steps 9.3, 9.4, and
                   9.5.

12   Data Analysis and Calculations
     12.1. The final sample test source  (filter mounted on a planchet) will need to have at least a
          24-hour ingrowth for 225Ac (and 221Fr and 217At) to meet Analytical Protocol
          Specifications for chemical yield with a counting time of 4 hours. At-217 (third


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           progeny of 225Ra) has a single, distinct alpha peak with a centroid at 7.067 MeV and
           is used for determining the yield.

           Note: Actinium 225 and other decay progeny from the 225Ra (e.g., 217At) tracer will continue to
           ingrow as time elapses between separation and the count of the sample. Delaying the count
           significantly longer than a day may introduce a possible positive bias in results near the detection
           threshold. When sample counting will be delayed longer than 36 hours, and MQOs foresee
           decisions being made close to detection levels, the impact of tracer progeny tailing should be
           minimized. Possible approaches for accomplishing this may include improving the signal to noise
           ratio by: 1) Processing a larger sample aliquant; 2) Decreasing the tracer activity added to a level
           that will still provide adequate statistics ~400-1500 net counts at the time of the analysis but will
           minimize spilldown into the 226Ra ROI.

      12.2. While the radiochemical yield is not directly used to determine the 226Ra activity of
           the sample, the following equation can be used to calculate the radiochemical yield
           (see Reference 16.6), if required:

                   RY =
                         s x At x It
           Where:
               RY      =    Fractional radiochemical yield based on 225Ra (from ingrown 217At
                              at 7.07 MeV)
               Rt       =    Total count rate beneath the 217At peak at 7.07 MeV, cpm
               R\,       =    Background count rate for the same region, cpm
               e        =    Efficiency for the alpha spectrometer

           Note: If 225Ra is separated from 229Th for use as a purified tracer, the 225Ra activity is
           unsupported and begins to decay at the point of separation from 229Th, and not in Stepll.3.6.
           Instead, the reference date and time established when the tracer is standardized is used for decay
           correction of the 225Ra activity. If 229Th solution (with 225Ra in full secular equilibrium) is added
           to the sample, the 225Ra activity is equal to the 229Th activity added and only begins to decay at
           the point of separation of 225Ra from 229Th in Step 11.3.6.

               At       =    The  activity of 217At at midpoint of the count (the target value that
                              should be achieved for 100% yield), in dpm.

                              =  3.0408 (/tK5

               A22SRa    =    Activity in dpm of 225Ra tracer added to the sample in Step 11.1.3
                              decay corrected to the date and time of radium  separation in
                              Stepll.3.6.6
6 When separated 225Ra tracer is added to the sample, its initial activity, yl225Ra-imtiai, must be corrected for decay from
the reference date established during standardization of the tracer to the point of separation of 225Ra and 225Ac as
follows:

           Ra   \   Ra-initial
where:  h\ = decay constant for 225Ra (0.04652 d~:); and dt = time elapsed between the activity reference date for the
225Ra tracer solution added to the sample and the separation of 225Ra and 225Ac in Step 11.3.6 (days).

When 229Th containing ingrown 225Ra is added directly to the sample, the amount of 225Ra ingrown since purification
of the 229Th solution is calculated as:
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              d        =    Elapsed ingrowth time for 225Ac [and the progeny 217At], in days
                            from the date and time of Ra separation to the midpoint of the
                            sample count
              AI        =    0.04652 d'1 (decay constant for 225Ra - half-life = 14.9 days)
              A2        =    0.06931 d'1 (decay constant for 225Ac) - half-life = 10.0 days)
              /t        =    Fractional abundance for the 7.07 MeV alpha peak counted (=
                            0.9999)
              3.0408   =   A2 /\A2  A^} [a good approximation as the half lives of 221Fr and
                            217At are short enough so that secular equilibrium with 225Ac is
                            ensured]

     12.3. The activity concentration of an analyte and its combined standard uncertainty are
          calculated using the following equations:
                            AC=.
                                   VaxRnixDaxIax2.22
           «.HC.) =        )x   ,    ,        ,
            ^    "•        *"*     2    2    2    L
           where:
              ACa       =  activity concentration of the analyte at time of count, (pCi/L)
              At         =  the theoretical activity of 217At at midpoint of the count that should
                            be achieved for 100% yield, in dpm (see Step 12.2 for detailed
                            calculation)
              Rna        =  net count rate of the analyte in the defined region of interest (ROI),
                            in counts per minute (Note that the peaks at 4. 784 and 4. 602 MeV
                            are generally included in the ROI for 226Ra)
              Rnt        =  net count rate of the tracer in the defined ROI, in counts per minute
              Fa         =  volume of the sample aliquant (L)
              Da,         =  correction factor for decay of the analyte from the time of sample
                            collection (or other reference time) to the midpoint of the counting
                            period, if required
              /a         =  probability of a emission for 226Ra (The combined peaks at 4. 78
                            and 4. 602 Me V are generally included in the ROI with an
                            abundance of LOO.}1
              uc(ACa)    =  combined standard uncertainty of the activity concentration of the
                            analyte (pCi/L)
              u(At)      =  standard uncertainty of the activity of the tracer added to the
                            sample (dpm)

where: ^4229Th = Activity of the 229Th standard on the date of the separation of Th and Ra (Step 11.3.6); ^ = decay
constant for 225Ra (0.04652 d"1); and dl = time elapsed between the purification of 229Th solution added to the sample
and the separation of 225Ra and 229Th/225Ac in Step 1 1.3.6 (days).
7 If the individual peak at 4.78 MeV used, and completely resolved from the 4. 602 MeV peak, the abundance would
be 0.9445.


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           Radium-226 in Water: Rapid Radiochemical Method for High-Activity Samples


               z/(Fa)      =   standard uncertainty of the volume of sample aliquant (L)
               u(Rna)     =   standard uncertainty of the net count rate of the analyte in counts
                              per minute
               u(Rni)      =   standard uncertainty of the net count rate of the tracer in counts per
                              minute

           Note: The uncertainties of the decay-correction factors and of the probability of decay factors
           are assumed to be negligible.

           Note: The equation for the combined standard uncertainty (uc(ACa)} calculation is arranged to
           eliminate the possibility of dividing by zero if Ra = 0.

           Note: The standard uncertainty of the activity of the tracer added to the sample must reflect that
           associated with the activity of the standard reference material and any other significant sources
           of uncertainty such as those introduced during the preparation of the tracer solution (e.g.,
           weighing or dilution factors) and during the process of adding the tracer to the sample.

           12.3.1   The net count rate of an analyte or tracer and its standard uncertainty can be
                    calculated using the following equations:
                        Rnx    =    net count rate of analyte or tracer, in counts per minute8
                        Cx     =    sample counts in the analyte or the tracer ROI
                        4      =    sample count time (min)
                        Cbx    =    background counts in the same ROI as for x (x refers to the
                                     respective analyte or tracer count)
                        tb      =    background count time (min)
                        u(Rnx) =    standard uncertainty of the net count rate of tracer or
                                     analyte, in counts per minute

           12.3.2   If the critical level concentration (Sc) or the minimum detectable
                    concentration (MDC) are requested (at an error rate of 5%), they can be
                    calculated using the following equations.9
 For methods with very low counts, MARLAP Section 19.5.2.2 recommends adding one count each to the gross
counts and the background counts when estimating the uncertainty of the respective net counts. This minimizes
negative bias in the estimate of uncertainty and protects against calculating zero uncertainty when a total of zero
counts are observed for the sample and background.
9 The formulations for the critical level and minimum detectable concentration are based on the Stapleton
Approximation as recommended in MARLAP Section 20A.2.2, Equations 20.54 and 20A.3.2, and Equation 20.74,
respectively. The formulations presented here assume an error rate of a = 0.05, ft = 0.05 (with Z!_a = zi-p = 1.645),


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0.4 x M- -1 + 0.677 x 1 + -M +1.645 x
               ,'-
    S=-
                                                                             4 x Dt x It
                                       tsxVaxRtxDax!a
    MDC =
             2.71x 1 +  -  +3.29x  Rt
                       b
                                    bas
                                           A
            where:
               Rbn   =    background count rate for the analyte in the defined ROI, in counts
                          per minute

    12.4  Results Reporting
          12.4.1   The following data should be reported for each result: volume of sample
                   used; yield of tracer and its uncertainty; and full width at half maximum
                   (FWHM) of each peak used in the analysis.
          12.4.2   The following conventions should be used for each result:
                   12.4.2.1 Result in scientific notation ± combined standard uncertainty.
                   12.4.2.2 If solid material was filtered from the solution and analyzed
                           separately, the results of that analysis should be reported separately
                           as pCi/L of the original volume from which the solids were filtered
                           if no other guidance is provided on reporting of results for the
                           solids. For example:
                           226Ra for Sample 12-1-99:
                                    Filtrate Result:            12.8 ± 1.5 pCi/L
                                    Filtered Residue Result:    2.5 ± 0.3 pCi/L

13 Method Performance
   13.1   Results of method validation performance are to be archived and available for
          reporting purposes.
   13.2   Expected turnaround time for an individual sample is -35 hours and per batch is -38
          hours.

14 Pollution Prevention
   14.1   The use of MnO2 and Diphonix® resin reduces the amount of solvents that would
          otherwise be needed to co-precipitate and purify the final sample test source.

15 Waste Management
   15.1   Nitric acid and hydrochloric acid wastes should be neutralized before disposal and
          then disposed of in accordance with local ordinances.

and d = 0.4. For methods with very low numbers of counts, these expressions provide better estimates than do the
traditional formulas for the critical level and MDC.


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          Radium-226 in Water: Rapid Radiochemical Method for High-Activity Samples


   15.2   All final precipitated materials contain tracer and should be dealt with as radioactive
          waste and disposed of in accordance with the restrictions provided in the facility's
          NRC license.

16 References
   16.1   RAW04-10,  "Radium-226/228 in Water (MnO2 Resin and DGA Resin Method),"
          Eichrom Technologies, Lisle Illinois (June 2006).
   16.2   A Rapid Method For Alpha-Spectrometric Analysis of Radium Isotopes in Natural
          Waters Using Ion-Selective Membrane Technology; S. Purkl and  A. Eisenhauer.
          Applied Radiation and Isotopes 59(4):245-54 (Oct 2003).
   16.3   U.S. Environmental Protection Agency (EPA). 2009. Method Validation Guide for
          Radiological Laboratories Participating in Incident Response Activities. Revision 0.
          Office of Air and Radiation, Washington, DC. EPA 402-R-09-006, June. Available
          at: www.epa.gov/narel/incident guides.html.
   16.4   Multi-Agency Radiological Laboratory Analytical Protocols Manual (MARLAP).
          2004. EPA 402-B-1304 04-001A, July. Volume I, Chapters 6, 7, 20, Glossary;
          Volume II and Volume III, Appendix G. Available at: www.epa.gov/radiation/
          marlap/index.html.
   16.5   ASTM D7282 "Standard Practice for Set-up, Calibration, and Quality Control of
          Instruments Used for Radioactivity Measurements," ASTM Book of Standards 11.02,
          current version,  ASTM International, West Conshohocken, PA.
   16.6   S. Purkl and  A. Eisenhauer (2003).  "A Rapid Method for Alpha-Spectrometric
          Analysis of Radium Isotopes in Natural Waters Using Ion-Selective Membrane
          Technology." Applied Radiation and Isotopes 59(4):245-54.
                                    226
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          Radium-226 in Water: Rapid Radiochemical Method for High-Activity Samples
17  Tables, Diagrams, and Flow Charts
    17.1    Tables [including major radiation emissions from all radionuclides separated]

            Table 17.1 Alpha Particle Energies and Abundances of Importance
Energy
(MeV)
4.601
4.784
4.798
4.815
4.838
4.845
4.901
4.968
4.979
5.053
5.434
5.449
5.489
5.540
5.580
5.607
5.609
5.637
5.682
5.685
5.716
5.724
5.732
5.732
5.747
Abundance
(%)
5.6
94.5
1.5
9.3
5.0
56.2
10.2
6.0
3.2
6.6
2.2
5.1
99.9
9.0
1.2
25.2
1.1
4.4
1.3
94.9
51.6
3.1
8.0
1.3
9.0
Nuclide
Ra -226
Ra -226
Th-229
Th-229
Th-229
Th-229
Th-229
Th-229
Th-229
Th-229
Ra-223
Ra-224
Rn-222
Ra-223
Ac -225
Ra -223
Ac -225
Ac -225
Ac -225
Ra -224
Ra -223
Ac -225
Ac -225
Ac -225
Ra -223
                    - Analyte
Energy
(MeV)
5.791
5.793
5.830
5.869
6.002
6.051
6.090
6.126
6.243
6.278
6.288
6.341
6.425
6.553
6.623
6.778
6.819


7.386
7.450
7.687
8.376
8.525
11.660
Abundance
(%)
8.6
18.1
50.7
1.9
100.0
25.1
9.8
15.1
1.3
16.2
99.9
83.4
7.5
12.9
83.5
100.0
79.4


100.0
98.9
100.0
100.0
2.1
96.8
Nuclide
Ac -225
Ac -225
Ac -225
Bi-213
Po -218
Bi-212
Bi-212
Fr-221
Fr-221
Bi-211
Rn-220
Fr-221
Rn-219
Rn-219
Bi-211
Po-216
Rn-219


Po-215
Po-211
Po-214
Po-213
Po-212
Po-212
                                                  217
           At (3rd progeny of  Ra tracer)
      [	| - 229Th (Check ROI for indications of inadequate clean-up)
       Includes only alpha particles with abundance > 1%.
       Reference: NUDAT 2.4, Radiation Decay National Nuclear Data Center, Brookhaven National
       Laboratory; Available at: www.nndc.bnl.sov/nudat2/indx dec.jsp; Queried: November 11, 2007.
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         Radium-226 in Water: Rapid Radiochemical Method for High-Activity Samples
   17.2  Ingrowth curves and Ingrowth factors
         1000
          0.1
                       Ac-225 In-Growth in Ra-225
                     200
400     600
Time, Hours
      800     1000
                         Ra-225 In-Growth in Th-229
                   20      40
   60
  Days
                                                               -Th-229, dpm
                                                               - Ra-225, dpm
80     100     120
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           Radium-226 in Water: Rapid Radiochemical Method for High-Activity Samples
                        Table 17.2. Ingrowth Factors for 217At in 225Ra
Time elapsed between
separation of Ra and
midpoint of count
in hours
Ingrowth Factor*
Time elapsed between
separation of Ra and
midpoint of count
in hours
Ingrowth Factor*

1

0.002881

72

0.1748

2

0.005748

96

0.2200

3

0.008602

120

0..2596

4

0.01144

144

0.2940

5

0.01427

192

0.3494

6

0.01708

240

0..3893

24

0.06542

360

0.4383

48

0.1235

480

0.4391
 'ingrowth Factor represents the fraction of217Ac activity at the midpoint of the sample count relative to the 225Ra
 activity present at the date/time ofRa separation. These ingrowth factors may be closely approximated (within a
fraction of a percent) using the expression for At in Step 12.2.2.
                        Table 17.3 Ingrowth Factors for 225Ra in 229Th
Time elapsed between
purification of the 229Th
standard and date of Ra
separation
in days
Ingrowth Factor*
Time elapsed between
purification of the 229Th
standard and date of Ra
separation
in days
Ingrowth Factor*
1

0.04545
50

0.9023
5

0.2075
55

0.9226
10

0.3720
60

0.9387
12

0.4278
70

0.9615
15

0.5023
80

0.9758
20

0.6056
90

0.9848
25

0.6875
100

0.9905
27

0.7152
130

0.9976
30

0.7523
160

0.9994
40

0.8445
200

0.9999
 Ingrowth Factor represents the fraction  Ra activity/  Th activity at the time ofRa separation.
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          Radium-226 in Water: Rapid Radiochemical Method for High-Activity Samples
                                                               225T
                       Table 17.4 Decay Factors for Unsupported   Ra
Time elapsed
between separation
of229Thand225Ra
in days
Decay Factor*
Time elapsed
between separation
of229Thand225Ra
in days
Decay Factor*
1

0.9545
50

0.09769
5

0.7925
55

0.07741
10

0.6280
60

0.06135
12

0.5722
70

0.03853
15

0.4977
80

0.02420
20

0.3944
90

0.01519
25

0.3125
100

0.00954
27

0.2848
130

0.00236
30

0.2477
160

0.00059
40

0.1555
200

0.00009
Decay Factor represents the fraction  Ra activity remaining.
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            Radium-226 in Water: Rapid Radiochemical Method for High-Activity Samples
     17.3   Example Alpha Spectrum from a Processed Sample
     100^
      80
 3
 o
O
                     5000
                                                216Po6/219Rnn
                                                                            •background
                                                                            •1
                                                                          5  Th-series
                                                                          s  Np-series
                                                                          :  U-Ra-series
                                                                             Ac-series
6000
7000
8000
9000
                                            Energy/keV
     Reference: Purkl, Stefan, Dissertation: Entwicklung und Anwendung neuer analytischer Methoden zur
     schnellen Bestimmung von kurzlebigen Radiumisotopen und Radon im Grundwasserbeeinflussten Milieu der
     Ostsee; Chapter 2, Figure 3; Christian-Albrechts Universitaet, Kiel, Germany, 2003.
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          Radium-226 in Water: Rapid Radiochemical Method for High-Activity Samples
   17.4   Decay Schemes for Analyte and Tracer
                 a
                164 MS
     22.2 y

        P
                            226Ra Decay Scheme
                                   Secular equilibrium is
                                   established between 22BRa
                                   and 222Rn in about 18 days.
1 h
3.1 min
  Q
      27 min

         P
                                           1,600y
                                           a
                                                                 3.8 d
                                                                 a
It takes about 4 hours for secular
equilibrium to be established
between 222Rn and 214Po after
fresh 222Rn is separated.
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            Radium-226 in Water: Rapid Radiochemical Method for High-Activity Samples
    17.5    Flowchart
                         Note: Shaded figures are associated with the timeline.
     11.1.1 to 11.1.5
     Aliquant sample.
     Add nitric acid,
    tracer and barium
    carrier and digest.
                       Separation Scheme and Timeline for 226Ra
  11.3.1 to 11.3.2
 Prepare and pre-
condition Diphonix
     column.
11.1.6
Reduce volume and
reconstitute with
with 100mL
of 1MHCL.


                            11.2.5.1 or 11.2.5.2
                            Equilibrate sample
                            with Mn02 resin for
                               30-90 min.
         11.2.1 to 11.2.4
        Add NaOH and filter
      to remove parti culates.
        Add calcium nitrate.
      Add indicator and adjust
          pHto neutral.
                                      11.2.6
                                  Transfer Mn02
                                 resin to a column.
                                    Rinse with
                                demineralized water.
                                  Discard eluent.
      11.3.3 to 11.3.4
Load solution fromtvln02 onto
   Diphonix column and
   allow to gravity drain.
 Elute with two more 5-mL
   all quants of 2M HCI.
          11.2.7
        Add 10 ml
     2M HCI/0.6% H202
   to strip Mn02 resin into
      centrifuge tube.
                                 11.3.5
                           Collect, load, and rinse
                            eluates containing
                                 radium.
                    11.4.1 to 11.4.6
                 Add ammonium sulfate,
                    isopropanol, and
                     ultrasonicate
                   topptRa/BaS04.
     1     2.5
4                  6
    Timeline (Hours)
   7.
30
34
37
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           Radium-226 in Water: Rapid Radiochemical Method for High-Activity Samples
Appendix A:
Composition of Atlanta Drinking Water Used for this Study
Metals by ICP-AES
Silicon
Aluminum
Barium
Calcium
Iron
Magnesium
Potassium
Sodium
Inorganic Anions
Chloride
Sulfate
Nitrogen, Nitrate (as N)
Carbon Dioxide
Bicarbonate Alkalinity
Carbonate Alkalinity
Radionuclide
Uranium 234, 235, 238
Plutonium 238, 239/240
Americium 24 1
Strontium 90
Radium 226***
Concentration (mg/L)*
3.18
<0.200
0.0133
9.38
<0.100
<0.500
<0.500
<0.500

12.7
15.6
1.19

23.8
<3.00
Concentration (pCi/L)**
<0.01,<0.01,<0.01
<0.02, <0.02
<0.02
<0.3
0.11 ±0.27
-0.30 ±0.45
           Note: Analyses conducted by independent laboratories.
           *   Values below the reporting level are presented as less than (<) values.
               No measurement uncertainty was reported with values greater than the "Reporting
               Level."
            **  Reported values represent the calculated minimum detectable concentration (MDC)
               for the radionuclide(s).
           *** Two samples analyzed. Expanded uncertainty (k=2) as reported by the laboratory.
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          Radium-226 in Water: Rapid Radiochemical Method for High-Activity Samples


                                      Appendix B:
     Preparation and Standardization of 225Ra Tracer Following Separation from 229Th

Bl. Summary Description of Procedure

This procedure describes a 225Ra generator to make tracer amounts of 225Ra using a 229Th
solution. Th-229 is separated from 225Ra using Y(OH)3 co-precipitation. Th-229 is carried in the
precipitate and most of the 225Ra remains in solution. Centrifugation to remove 229Th in the
precipitate and filtration of the supernate produces the 225Ra tracer solution. The 225Ra activity of
the tracer solution is standardized by counting sample test sources prepared from at least five
replicate aliquants of the 225Ra solution, each spiked with a known quantity of a 226Ra standard.
This standardized activity concentration, referenced to the date and time of the 225Ra separation
described in Step4.11.7 below, is then decay-corrected to the date and time of subsequent sample
analyses.

The Y[Th](OH)3 precipitate may be stored and re-used later to generate more 225Ra tracer
         T)S                  OOQ
solution.  Ra ingrows in the   Th fraction (Y(OH)3 precipitate) and after 50 days will be about
90% ingrown. After sufficient ingrowth time 225Ra may be harvested to make a fresh 225Ra tracer
solution by dissolving the precipitate and re-precipitating Y(OH)3to separate 229Th from 225Ra.
Multiple 225Ra generators may be prepared to ensure that 225Ra tracer will be continuously
available. The 225Ra tracer solution produced is usable for 2-3 half-lives (-30-45 days). To
minimize effort involved with standardization of the 225Ra solution, it is recommended that the
laboratory staff prepare an amount of 229Th sufficient to support the laboratory's expected
workload for 3-5 weeks. Since the 229Th solution is reused, and the half-life of 229Th is long
(7,342 years), the need to purchase a new certified 229Th solution is kept to a minimum.

B2. Equipment and Supplies
    B2.1.  Refer to Section 6 of the main procedure.

B3.Reagents and Standards
    B3.1.  Refer to Section 7 of the main procedure.

B4. Procedure
    B4.1.  Add a sufficient amount of 229Th solution (that which will yield at least 150-600
          dpm/mL of the 225Ra solution) to a 50-mL centrifuge tube.15
    B4.2.  Add 20 mg Y (2 mL of 10 mg/mL Y metals standard stock solution).
    B4.3.  Add 1 mg Ba (0.1 mL of 10 mg/mL Ba metals standard stock solution).
    B4.4.  Add 4 mL of concentrated ammonium hydroxide to form Y(OH)3 precipitate.
    B4.5.  Centrifuge and decant the supernatant into the open barrel of a 50-mL syringe, fitted
          with a 0.45-|im syringe filter. Hold the syringe barrel over a new 50-mL centrifuge
          tube while decanting. Insert the syringe plunger and filter the supernatant into the new
          centrifuge tube. Discard the filter as potentially contaminated rad waste.
15 For example, if 40 mL of a 229Th solution of 600 dpm/mL is used, the maximum final activity of 225Ra will be
~510 dpm/mL at Step B4.8. This solution would require about 1.4 mL for the standardization process and about 8
mL for a batch of 20 samples.


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          Radium-226 in Water: Rapid Radiochemical Method for High-Activity Samples


   B4.6.  Cap the centrifuge tube with the precipitate, label clearly with the standard ID,
          precipitation date, and the technician's initials and store for future use.
   B4.7.  Properly label the new centrifuge tube with the supernate. This is the 225Ra tracer
          solution.
   B4.8.  Add 3 mL of concentrated HC1 to 225Ra tracer solution. Cap centrifuge tube and mix
          well.
   B4.9.  Prepare the following solutions in 10 mL of 2-M HC1 for standardization of 225Ra
          tracer.

           Solution           Spike(s)
           Standardization    -80 dpm of the 225Ra tracer solution, and
           Replicates         ~8 dpm of a 226Ra standard traceable to NIST or
           (5 replicates)       equivalent

           Blank             -80 dpm of the 225Ra tracer solution (the blank
                             should be evaluated to confirm that 226Ra is not
                             detected in the 225Ra tracer solution at levels that
                             may compromise sample results when used in the
                             method)

           Standardization    -80 dpm of the 225Ra tracer solution, and
           Control Sample    -8 dpm of a second source independent traceable
                             226Ra standard (the Standardization Control Sample
                             should be evaluated to confirm that the standardiza-
                             tion process does not introduce significant bias into
                             the standardized value for the 225Ra tracer)

   B4.10. Add 75 |ig Ba (0.075 mL of 1000 |ig/mL Ba) to all solutions.
   B4.11. Process the solutions to prepare sources for alpha spectrometry as follows:
          B4.11.1.  Slurry -1.0 g of Diphonix® resin per column in water.
          B4.11.2.  Transfer the resin to 0.8 cm (ID.) x 4 cm columns to obtain a uniform
                    resin bed.
          B4.11.3.  Precondition the columns by passing 20 mL 2 M HC1 through the
                    columns. Discard the effluent.
          B4.11.4.  Place clean 50-mL centrifuge tubes under the columns.
          B4.11.5.  Load the solutions from Step B4.10 onto the columns. Collect the
                    effluents in the 50-mL centrifuge tubes. Allow the solutions to flow by
                    gravity.
          B4.11.6.  When the load solutions have  stopped flowing, rinse columns with two 5-
                    mL volumes of 2-M HC1. Collect the rinse solutions in the same 50-mL
                    centrifuge tubes (the total volume will be about 20 mL).
          B4.11.7.  Record the date and time of the last rinse as the date and time of
                    separation of radium (beginning of 225Ac ingrowth).
          B4.11.8.  Add -3.0 grams of (NH4)2SO4 to the solutions from Step B4.11.6. Mix
                    gently to dissolve.
          B4.11.9.  Add 5.0 mL of isopropanol and mix gently.
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          B4.11.10. Place in an ultrasonic bath filled with cold tap water for at least 20
                    minutes.
          B4.11.11. Filter the suspensions through pre-wetted (using methanol or ethanol) 0.1-
                    um filters.
          B4.11.12. Rinse the filters with three 2-mL portions of 20% isopropanol. Allow each
                    rinse to completely pass through filter before adding the next rinse.
          B4.ll.13. Rinse each filter with about 2 mL of methanol or ethanol.
          B4.11.14. Carefully place each filter face-side up on a labeled stainless steel
                    planchet, or other suitable source mount, which has previously been
                    prepared with an appropriate adhesive (e.g., double stick tape).
          B4.11.15. Dry under a heat lamp for a few minutes.
          B4.11.16. After allowing about 24-hours ingrowth, count the standardization sources
                    by alpha spectrometry.
   B4.12. Calculate the activity of 225Ra, in units of dpm/mL, in the standardization replicates,
          at the 225Ra time of separation as follows:
   where:
      Amn    =   Activity concentration of 225Ra, in dpm/mL [at the time of separation from
                  229Th, Step B4.11.7]
              =   Total counts beneath the 217At peak at 7.07 MeV
              =   Total counts beneath the 226Ra peak at 4.78 MeV
      Nb      =   Background count rate for the corresponding region of interest,
      4       =   Duration of the count for the sample test source, minutes
      tb       =   Duration of the background count, minutes
      A       =   Activity of 226Ra added to each aliquant, in dpm/mL
       226Ra
      F22g     =   volume of 226Ra solution taken for the analysis (mL)
      V       =   volume of 225Ra solution taken for the analysis (mL)
       225Ra
      d       =   Elapsed ingrowth time for 225Ac [and the progeny 217At], from separation to
                  the midpoint of the sample count, days
      Ai       =   0.04652 d"1 (decay constant for 225Ra - half-life = 14.9 days)
      A2       =   0.06931 d'1 (decay constant for 225Ac) - half-life = 10.0 days)
      /t       =   Fractional abundance for the 7.07 MeV alpha peak counted (= 0.9999)
      3.0408  =   X2dj(X2d - \d) [a good approximation as the half lives of 221Fr and 217At are
                  short enough so secular equilibrium with 225Ac is ensured]

   Note: The activity of the separated A22SRa will need to be decay corrected to the point of separation in the
   main procedure (Step 11.3.6) so that the results can be accurately determined.
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          Radium-226 in Water: Rapid Radiochemical Method for High-Activity Samples
                                                                  225T
   B4.13. Calculate the uncertainty of the activity concentration of the   Ra tracer at the
          reference date/time:
                      3.0408x/!17  x \e-^d-e-^d)\ xV2,
           
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                                         www.epa.gov
                                         February 2010
                                           Revision 0
     Rapid Radiochemical Method for
  Total Radiostrontium (Sr-90) In Water
for Environmental Restoration Following
         Homeland Security Events
            U.S. Environmental Protection Agency

               Office of Air and Radiation
             Office of Radiation and Indoor Air
       National Air and Radiation Environmental Laboratory
                 Montgomery, AL 36115

            Office of Research and Development
         National Homeland Security Research Center
                 Cincinnati, OH 45268

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                      TOTAL RADIOSTRONTIUM (SR-90) IN WATER:
                      RAPID METHOD FOR HIGH-ACTIVITY SAMPLES

1.  Scope and Application
   1.1.   The method will be applicable to samples where the source of the contamination is
         either from known or unknown origins. If any filtration of the sample is performed
         prior to starting the analysis, those solids should be analyzed separately. The results
         from the analysis of these solids should be reported separately (as a suspended activity
         concentration for the water volume filtered), but identified with the filtrate results.
   1.2.   The method provides a very rapid non-radioisotope-specific screen for total
         radiostrontium in drinking water and other aqueous samples.
   1.3.   This method uses rapid radiochemical separations techniques for the determination of
         beta-emitting strontium radioisotopes in water samples following a nuclear or
         radiological incident. Although this method can detect concentrations of 90Sr on the
         same order of magnitude as methods used for the Safe Drinking Water Act (SDWA),
         this method is not a substitute for SDWA-approved methods for radiostrontium.
   1.4.   The method is capable of satisfying a required method uncertainty for 90Sr (total as
         90Sr) of 1.0 pCi/L at an analytical action level of 8.0 pCi/L. To attain the stated
         measurement quality objectives (MQOs) (see Step 9.2), a sample volume of
         approximately 500 mL and a count time of approximately 1.25 hours are
         recommended. The sample turnaround time and throughput may vary based on
         additional project MQOs, the time for analysis of the final counting form  and initial
         sample volume. The method must be validated prior to use following the protocols
         provided in Method Validation Guide for Qualifying Methods Used by Radiological
         Laboratories Participating in Incident Response Activities (EPA 2009, reference  16.3).
   1.5.   This method is intended  to be used for water samples that are similar in composition to
         drinking water. The rapid 90Sr method was evaluated following the guidance presented
         for "Level E Method Validation: Adapted or Newly Developed Methods, Including
         Rapid Methods" in Method Validation Guide for Qualifying Methods Used by
         Radiological Laboratories Participating in Incident Response Activities (EPA 2009,
         reference 16.3) and Chapter 6 of Multi-Agency Radiological Laboratory Analytical
         Protocols Manual (MARLAP 2004, reference 16.4). The matrix used for the
         determination of 90Sr was drinking water from Atlanta, GA.  See Appendix C of this
         method for a listing of the chemical constituents of the water. Multi-radionuclide
         analysis using sequential separation may be possible.
   1.6.   This method is applicable to the determination of soluble radiostrontium.  This method
         is not applicable to the determination of strontium isotopes contained in highly
         insoluble particulate matter possibly present in water samples contaminated as a result
         of a radiological dispersal device (RDD) event.
   1.7.   Sequential, multi-radionuclide analysis may be possible by using this method in
         conjunction with other rapid methods.

2.  Summary of Method
   2.1.   Strontium is isolated from the matrix and purified from potentially interfering
         radionuclides and matrix constituents using a strontium-specific, rapid chemical
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          Total Radiostrontium (90Sr) in Water: Rapid Method for High-Activity Samples


         separation method. The sample is equilibrated with strontium carrier, and concentrated
         by Sr/BaCOs coprecipitation. If insoluble residues are noted during acid dissolution
         steps, the residue and precipitate mixture is digested in 8 M HNOs to solubilize
         strontium. The solution is passed through a Sr-Resin™ extraction chromatography
         column1 that selectively retains strontium while allowing most interfering radionuclides
         and matrix constituents to pass through to waste. If present in the sample, residual
         plutonium and several interfering tetravalent radionuclides are stripped from the
         column using an oxalic/nitric acid rinse. Strontium is eluted from the column with 0.05
         M HNOs and taken to dryness in a tared, stainless steel planchet. The planchet
         containing the strontium nitrate precipitate is weighed to determine the strontium yield.
    2.2.  The sample test source is promptly counted on a gas flow proportional counter to
         determine the beta emission rate, which is used to calculate the total radiostrontium
         activity.
         2.2.1.  This test assumes that it is reasonable to assume the absence of 89Sr in the
                sample. In such cases, a total radiostrontium analysis will provide for a specific
                determination of 90Sr in the sample. The same prepared sample test source can
                be recounted  after -1-21 days to verify the total radiostrontium activity. If the
                initial and second counts agree, this is an indication that 89Sr is not present in
                significant amounts relative to 90Sr (within the uncertainty of the measurement).
         2.2.2.  Computational methods are available for resolving the concentration of 89Sr and
                90Sr from two sequential counts of the sample. An example of an approach that
                has been used successfully at a number of laboratories is presented in Appendix
                B to this method.  It is the responsibility of the laboratory, however, to validate
                this approach prior to its use.

3.  Definitions, Abbreviations, and Acronyms
    3.1.  Analytical Protocol Specification (APS). The output of a directed planning process that
         contains the project's analytical data needs and requirements in an organized, concise
         form.
    3.2.  Analytical Action Level (AAL). The term analytical action level is used to denote the
         value of a quantity that will cause the decisionmaker to choose one of the alternative
         actions.
    3.3.  Analytical Decision Level (ADL). The analytical decision level refers to the value that
         is less than the AAL  based  on the acceptable error rate and the required method
         uncertainty.
    3.4.  Discrete Radioactive Particles (DRPs or "hot particles"). Particulate matter in a sample
         of any matrix where a high concentration of radioactive material is contained in a tiny
         particle (um range).
    3.5.  Multi-Agency Radiological Analytical Laboratory Protocol Manual (see Reference
         16.4.)
1 Sr-Resin™ is a proprietary extraction chromatography resin consisting of octanol solution of 4,4'(5')-bis (t-butyl-
cyclohexano)-18-crown-6-sorbed on an inert polymeric support. The resin can be employed in a traditional
chromatography column configuration (gravity or vacuum) or in a flow cartridge configuration designed for use
with vacuum box technology. Sr-Resin is available from Eichrom Technologies, Lisle, IL.
                                    90
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          Total Radiostrontium (90Sr) in Water: Rapid Method for High-Activity Samples
   3.6.  Measurement Quality Objective (MQO). MQOs are the analytical data requirements of
         the data quality objectives and are project- or program-specific. They can be
         quantitative or qualitative. MQOs serve as measurement performance criteria or
         objectives of the analytical process.
   3.7.  Radiological Dispersal Device (RDD), i.e., a "dirty bomb." This is an unconventional
         weapon constructed to distribute radioactive material(s) into the environment either by
         incorporating them into a conventional bomb or by using sprays, canisters, or manual
         dispersal.
   3.8.  Required Method Uncertainty (MMR). The required method uncertainty is a target value
         for the individual measurement uncertainties and is an estimate of uncertainty (of
         measurement) before the sample is actually measured. The required method uncertainty
         is applicable below an AAL.
   3.9.  Relative Required Method Uncertainty (^R). The relative required method uncertainty
         is the WMR divided by the AAL and is typically  expressed as a percentage. It is
         applicable above the action level.
   3.10. Sample Test Source (STS). This is the final form of the sample that is used for nuclear
         counting. This form is usually specific for the nuclear counting technique in the
         method, such  as a solid deposited on a filter for alpha spectrometry analysis.
   3.11. Total Radiostrontium (also called Total Strontium): A radiological measurement that
         does not differentiate between 89Sr and 90Sr. The assumption is that all  of the strontium
         is in the form  of 90Sr. When it is certain that no 89Sr is present, the total radiostrontium
         activity is equal to the 90Sr activity and may be reported as such.

4.  Interferences
   4.1.  Radiological
         4.1.1.   Count results should be  monitored for detectable alpha activity  and appropriate
                corrective actions taken when  observed. Failure to address the presence of alpha
                emitters in the sample test source may lead to high result bias due to alpha-to-
               beta crosstalk.
                4.1.1.1.  Elevated levels of radioisotopes of tetravalent plutonium, neptunium,
                        cerium, and ruthenium in the sample may hold up on the column and
                        co-elute with strontium. The method employs an oxalic acid rinse that
                        should address low to moderate levels of these interferences in
                        samples.
                4.1.1.2.  The resin has a higher affinity for polonium than strontium. Under the
                        conditions of the analysis, however, polonium is not expected to elute
                        from the column.
         4.1.2.   Significant levels of 89Sr in the sample will interfere with the total
               radiostrontium analysis.
                4.1.2.1.  The absence of higher levels of interfering 89Sr may be detected by
                        counting the sample test source quickly after initial  separation
                        (minimizing ingrowth of 90Y), and then recounting the sample test
                        source after 1-21 days to verify that the calculated activity does not
                        change significantly.  The presence of 89Sr may be indicated when the
                        calculated activity of the second count is less than that of the first
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          Total Radiostrontium (90Sr) in Water: Rapid Method for High-Activity Samples
                        count by an amount greater than that which can be attributed to
                        statistical variation in the two analyses.
                4.1.2.2.  Alternatively, Appendix B provides a numerical approach for the
                        isotopic determination 89Sr and 90Sr from two sequential counts of the
                        sample, one immediately following separation, and one after a delay to
                        allow for ingrowth of 90Y and decay of 89Sr. Note that the approach in
                        Appendix B must be validated prior to use.
        4.1.3.  High levels of 210Pb may interfere with low-level strontium analysis due to
               ingrowth of short-lived 210Bi during chemical separations.  If 210Pb is known to
               be present in samples, minimizing the time between the final rinse and the
               elution of strontium to less than 15  minutes will maintain levels of interfering
               210Bi to less than 0.1% of the 210Pb  activity present. The presence or absence of
               interfering 210Bi  may be determined by recounting the sample test source to
               verify the half-life of the nuclide present.
        4.1.4.  High levels of 228Th or its decay progeny 224Ra and 212Pb may interfere with
               low-level strontium determinations due to ingrowth of short-lived decay
               products during chemical separations. Monitoring count data for alpha activity
               may provide indications of interferences. Minimizing the time between the final
               rinse and the elution of strontium from the column to 5 minutes should maintain
               levels of interfering 212Pb and 208T1 to less than 2% of the parent nuclide
                                                01 0
               activity. The presence or absence of  Pb may be determined by recounting the
               sample test source to verify the half-life of the nuclide present.
        4.1.5.  Levels of radioactive cesium or cobalt in excess of approximately 103 times the
               activity of strontium being measured may not be completely removed and may
               interfere with final results.
   4.2.  Non-Radiological
        4.2.1.  Chemical yield results significantly greater than  100% may indicate the
               presence of non-radioactive strontium native to the sample. If the quantity of
               native strontium in the sample aliquant exceeds -5% of the expected strontium
               carrier mass, chemical yield measurements will be affected and chemical yield
               corrections lead to low result bias unless the native strontium is accounted for in
               the yield calculations. When problematic levels of strontium are encountered,
               the native strontium content of the sample can be determined by an independent
               spectrometric measurement (such as inductively coupled plasma atomic
               emission spectroscopy [ICP-AES] or atomic absorption spectroscopy [AAS],
               etc). If the laboratory does not have access to instrumentation processing a split
               of the sample without the addition of strontium carrier may be used to obtain an
               estimate of the native strontium content of the sample.
        4.2.2.  Sr-Resin™ has a greater affinity  for lead than for strontium. Lead will
               quantitatively displace strontium from the column when the two are present in
               combined amounts approaching or  exceeding the capacity  of the column. If the
               combined quantity of lead and strontium carrier in the sample exceeds the
               capacity of the column, decreased strontium yields will be observed. Decreasing
               the sample size will help address samples with elevated levels of lead.
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          Total Radiostrontium (90Sr) in Water: Rapid Method for High-Activity Samples
        4.2.3.  High levels of calcium, barium, magnesium, or potassium may compete with
               strontium for uptake on the resin leading to low chemical yield. One should
               consider that yield results will overestimate the true strontium yield and cause a
               low result bias if these interfering matrix constituents are present as significant
               contaminants in the final sample test source.

5.   Safety
    5.1. General
        5.1.1.  Refer to your safety manual for concerns of contamination control, personal
               exposure monitoring and radiation dose monitoring.
        5.1.2.  Refer to the laboratory chemical hygiene plan for general chemical safety rules
    5.2. Radiological
        5.2.1.  Hot Particles (DRPs)
               5.2.1.1.  Hot particles, also termed "discrete radioactive particles" (DRPs), will
                        be small, on the order of 1 mm or less. Typically, DRPs are not evenly
                        distributed in the media and their radiation emissions are not uniform
                        in all directions (anisotropic). Filtration using a 0.45-um or finer filter
                        will minimize the presence of these particles.
               5.2.1.2.  Care should be taken to provide suitable containment for filter media
                        used in the pretreatment of samples that may have DRPs, because the
                        particles become highly statically charged as they dry out and will
                        "jump" to other surfaces causing contamination.
               5.2.1.3.  Filter media should be individually surveyed for the presence of these
                        particles, and this information reported with the final sample results.
        5.2.2.  For samples with detectable activity concentrations of these radionuclides,
               labware should be used only once due to potential for cross contamination.
    5.3. Procedure-Specific Non-Radiological Hazards:
        None noted.

6.   Equipment and supplies
    6.1. Analytical balance with 0.0001-g readability or better.
    6.2. Centrifuge able to accommodate 250-mL flasks and 50-mL centrifuge tubes.
    6.3. Centrifuge flasks, 250 mL, disposable.
    6.4. Centrifuge tubes, 50 mL, disposable.
    6.5. Low background gas flow proportional counter.
    6.6. Stainless steel planchets or other sample mounts: ~2-inch diameter.
    6.7. Vacuum box may be procured commercially, or constructed. Setup and use should be
        consistent with manufacturer instructions or laboratory SOP.
    6.8. Vacuum pump or laboratory vacuum system.

7.   Reagents and  Standards:

    Note: All reagents are American Chemical Society (ACS) reagent grade or equivalent unless otherwise
    specified.
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          Total Radiostrontium (90Sr) in Water: Rapid Method for High-Activity Samples
   Note: Unless otherwise indicated, all references to water should be understood to mean Type I Reagent
   water (AS TMD1193).

   7.1. Barium carrier solution (10 mg Ba/mL, standardization not required): Dissolve 19 g
        Ba(NO3)2 in water add 20 mL concentrated HNO3 and dilute to 1 L with water.
   7.2. Ethanol, reagent 95% (C2HsOH), available commercially.
   7.3. Nitric Acid, HNO3 (15.8M), concentrated, available commercially.
        7.3.1. Nitric acid (8 M): Add 506 mL of concentrated HNO3 to 400 mL of water and
               dilute to 1 L  with water.
        7.3.2. Nitric acid (3 M): Add 190 mL of concentrated HNO3 to 800 mL of water and
               dilute to 1 L  with water.
        7.3.3. Nitric acid (0.1 M): Add 6.3 mL of concentrated HNO3 to 900 mL of water and
               dilute to 1 L  with water.
        7.3.4. Nitric acid (0.05 M): Add 3.2 mL  of concentrated HNO3 to 900 mL water.
               Dilute to 1 L with water.
   7.4. Nitric acid (3M)/oxalic acid solution (0.05 M): Add 190 mL of concentrated HNO3
        (7.3) and 6.3 grams  of oxalic acid dihydrate (C2H2O4-2H2O), to 800 mL of
        demineralized water and dilute to 1 L with de-ionized water.
   7.5. Sodium carbonate (2 M): Dissolve 212 g anhydrous Na2CO3 in 800 mL of water, then
        dilute to 1 L with water.
   7.6. Sodium hydroxide (12 M): Dissolve 480 g of sodium hydroxide (NaOH) in 500 mL of
        water and dilute the  solution to 1 L in water.

        Caution: The dissolution of NaOH is strongly exothermic. Take caution to prevent boiling when
        preparing this solution. Use of a magnetic stirrer is recommended. Allow to cool prior to use.

   7.7. Sr-Resin™ columns,2 -0.7 g resin, small particle size (50-100 |j,m), in appropriately
        sized column or pre-packed cartridge.
   7.8. Strontium carrier solution, 5.00 mg/mL in 0.1-M HNO3, traceable to a national
        standards body such as NIST or standardized at the laboratory by comparison to
        independent standards.
        7.8.1. Option 1: Dilute elemental strontium standard to a concentration of 5.00 mg/mL
               (or mg/g) in  0.1-M HNO3.
        7.8.2. Option 2: To 200 mL de-ionized water, add 6.3 mL HNO3 and approximately
               12.07 g of strontium nitrate (Sr(NO3)2 dried to constant mass and the mass
               being determined to at least 0.001  g). Dilute to 1000 mL  with water. Calculate
               the amount of strontium nitrate/mL actually present and verify per Step 7.8.3.
        7.8.3. Prior to use,  verify the strontium carrier solution concentration as by
               transferring at least five 1.00-mL portions of the carrier to tared stainless steel
               planchets. Evaporate to dryness on a hotplate or under a heat lamp using the
               same technique as that used for samples. Cool in a desiccator and weigh as the
               nitrate to the nearest 0.1 mg.  The relative standard deviation for replicates
2 Available from Eichrom Technologies, Inc., Lisle IL.


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          Total Radiostrontium (90Sr) in Water: Rapid Method for High-Activity Samples
               should be less than 5% and the average residue mass within 5% of the expected
               value.
   7.9.  90Sr standard solution (carrier free), traceable to a national standards body such as
        NIST, in 0.5 M HNO3 solution.

   Sample Collection, Preservation and Storage
   8.1.  Samples should be collected in 1-L plastic containers.
   8.2.  No sample preservation is required if sample analysis is initiated within 3 days of
        sampling date/time.
        If the sample is to be held for more than three days, HNOs shall be added until pH<2.
        If the dissolved concentration of strontium is sought, the insoluble fraction must be
        removed by filtration before preserving with acid.

9.  Quality Control
   9.1.  Batch quality control  results shall be evaluated and meet applicable Analytical Project
        Specifications (APS) prior to release of unqualified data. In the absence of project-
        defined APS or a project-specific quality assurance project plan (QAPP), the quality
        control sample acceptance criteria defined in the laboratory quality manual and
        procedures shall be used to determine acceptable performance for this method.
        9.1.1.  A laboratory control sample (LCS) shall be run with each batch of samples. The
               concentration  of the LCS should be at or near the action level or a level of
               interest for the project.
        9.1.2.  One method blank shall be run with each batch of samples. The laboratory
               blank should consist of laboratory water.
        9.1.3.  One laboratory duplicate shall be run with each batch of samples. The
               laboratory duplicate is prepared by removing an aliquant  from the original
               sample container.
        9.1.4.  A matrix spike sample may be included as a batch quality control sample if
               there is concern that matrix interferences, such as the presence of elemental
               strontium in the sample, may compromise chemical yield measurements,  or
               overall data quality.
   9.2.  This method is capable of achieving a Z/MR of 1.0 pCi/L at or below an action level of
        8.0 pCi/L. This may be adjusted if the event-specific MQOs are different.
   9.3.  This method is capable of achieving a ^MR 13% above 8 pCi/L. This may be adjusted if
        the event-specific MQOs are different.
   9.4.  This method is capable of achieving a required minimum detectable concentration
        (MDC)of l.OpCi/L.

10. Calibration  and Standardization
   10.1. The effective detection efficiency for total radiostrontium (referenced to 90Sr) is
        calculated as the weighted sum of the 90Sr and 90Y efficiencies that reflects the relative
        proportions of 90Y and 90Sr based on the 90Y ingrowth after 90Sr separation.
   10.2. Set up, operate, and perform quality control for gas-flow proportional counters (GPC)
        in accordance with the laboratory's quality manual and standard  operating procedures,
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          Total Radiostrontium (90Sr) in Water: Rapid Method for High-Activity Samples
         and consistent with ASTM Standard Practice D7282, Sections 7-13 (see reference
         16.5).
    10.3. See Appendix A for details on calibration/standardization of the GPC specific to 90Sr
         and90Y.

11.  Procedure
    11.1.  For each sample in the batch, aliquant 0.5 L of raw or filtered water into a beaker.
          Add concentrated HNOs with mixing to bring the solution to a pH less than 2.0.

          Note: Smaller or larger aliquants may be used if elevated sample activity is present or as needed
          to meet detection requirements or MQOs. Method validations must be conducted using a volume
          equivalent in size to the sample size to be usedr

    11.2.  Add 1.00 mL (using a volumetric pipette) of 5 mg/mL strontium carrier and 0.5 mL
          barium carrier. Record the volume of strontium carrier added and the associated
          uncertainty of the mass of strontium added.
    11.3.  Place the beaker on a hotplate (for aliquants of 0.2 L a centrifuge cone in a hot water
          bath may also be used) and heat the solution to near boiling with occasional stirring.
    11.4.  Add -0.4-0.5 mL (8 -10 drops) 0.1% phenolphthalein indicator solution per 200 mL
          of sample. Add 12 M NaOH slowly with occasional stirring until a persistent pink
          color is obtained.

          Note: Additional phenolphthalein solution may be used if needed to provide a clear indication
          that the pH is above ~8.3. A slight excess of NaOH may be added.

    11.5.  Add 30 mL of 2-M Na2CC>3 to the sample and digest for 15 minutes with occasional
          stirring. Remove the sample from the hot plate and allow the solution to cool and the
          precipitate to settle.

          Note: Samples may be placed in an ice bath to expedite the cooling process.

          Note: If greater than a 0.2-L aliquant is used, the supernatant solution is decanted or an
          aspirator line used to remove as much supernatant solution as possible prior to transfer to a
          centrifuge tube.

    11.6.  Transfer the sample to a centrifuge tube and centrifuge for 3 to 5 minutes at 1500-
          2000 rpm. Discard supernatant solution.
    11.7.  Add 5 mL of 8-M HNOs to the centrifuge tube and vortex to dissolve the precipitate
          containing Sr.
    11.8.  If there are no undissolved solids visible in the sample and the sample is not from an
          ROD, or there is no reason to possibly suspect highly intractable material to be
          present (e.g., insoluble ceramics), proceed with Step 11.11.
    11.9.  If the sample contains undissolved solids or may contain intractable material, cover
          the tube to minimize evaporation of the solution and digest the solution on a hot water
          bath for 30 minutes. Allow to cool.
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          Total Radiostrontium (90Sr) in Water: Rapid Method for High-Activity Samples
     11.10.  If solids persist, remove by filtering solution through a glass fiber filter (1 urn or
            finer). The filter containing the solids should be analyzed separately for gross beta
            activity (90Sr efficiency) to determine whether the AAL may be exceeded
            (screening ADLs apply). The solution containing soluble strontium is retained as
            load solution for Step 11.13.

            Note: See Section 12.3.2 for reporting results when liquid and solid fractions are analyzed
            separately.

     11.11.  Set up a vacuum box for Sr-Resin™ columns or cartridges with minimum 10-15
            mL reservoirs according the manufacturer's instructions or laboratory SOP. The
            initial configuration should permit column effluents during the preconditioning,
            sample loading and rinses (Steps  11.12- 11.16) to be discarded to waste.
     11.12.  Add 5 mL of 8-M HNOs to precondition the column. Adjust the vacuum as
            necessary to maintain flow rates at < 3 mL/min. Discard preconditioning solution
            effluent.

            Note: Unless otherwise specified in the procedure, use a flow rate of ~ 1 mL/min for load and
            strip solutions and ~ 3 mL/min for rinse solutions.

     11.13.  Decrease the vacuum to obtain flow rates of < 1 mL/min. Load the sample from
            Step 11.8 or 11.10 into the column reservoir. When the solution reaches the top
            surface of the resin proceed with the next step. Discard column effluent.
     11.14.  Adjust the vacuum as necessary to maintain flow rates at < 3 mL/min. Rinse
            centrifuge tube with three successive 3 mL portions of 8-M HNCh adding the next
            one after the previous one reaches the top of the resin column. Discard column
            effluent.
     11.15.  If plutonium, neptunium, or radioisotopes of ruthenium or cerium may be present in
            the sample, add 10 mL 3-M HNOs - 0.05-M oxalic acid solution to each column.
            Allow the solution to completely  pass through the column prior to proceeding.
            Adjust the vacuum as necessary to maintain flow rates at < 3 mL/min. Discard
            column effluent.
     11.16.  Remove residual nitric/oxalic  acid solution with two 3 mL  rinses of 8-M HNCh,
            allowing each rinse solution to drain before adding the next one. Adjust the vacuum
            as  necessary to maintain flow  rates at < 3 mL/min. Record time and date of the end
            of last rinse to the nearest 15 minutes as t\,  "time of strontium separation." Discard
            column effluent.
     11.17.  Place clean 50 mL centrifuge tubes beneath the  columns to catch the strontium
            eluate before proceeding to the next step.
     11.18.  Decrease the vacuum as necessary to maintain flow  rates at < 1 mL/min. Elute
            strontium from the columns by adding 10 mL of 0.05-M HNOs.
     11.19.  Preparation of the STS and determination of chemical yield
            11.19.1. Clean and label a stainless steel planchet for each STS.
            11.19.2. Weigh and record the tare mass of each planchet to the nearest 0.1 mg.
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            11.19.3. Transfer the strontium eluate from Step 11.18 to the planchet and take to
                     dryness on a hotplate or under a heat lamp to produce a uniformly distributed
                     residue across the bottom of the planchet.
            11.19.4. When dry, place the sample in an oven at  105-110 °C until shortly before
                     sample test sources are ready for weighing. At that point, remove the STS
                     from the oven and allow it to cool in a desiccator before weighing.
            11.19.5. Weigh and record the gross  mass of each planchet to the nearest 0.1 mg.

                     Note: If the laboratory cannot operationally ensure that the precipitate has been
                     dried to constant mass, the mass stability of the precipitate should be demonstrated
                     by reheating the precipitate in an oven at 105-110 °C and reweighing. Since sample
                     self-attenuation is not a significant factor in the detection efficiency, the sample may
                     be counted prior to completion of this step if desired.

            11.19.6. Calculate  the chemical yield as presented in Section 12 of this method.
     11.20. Counting the Sample Test Source
            11.20.1. On a calibrated gas-flow proportional detector that has passed all required
                     daily performance and background checks, count the STS for a period as
                     needed to satisfy MQOs.
                     11.20.1.1.  If the presence of 89Sr cannot be excluded, and total
                                radiostrontium is being determined as a screen for the presence
                                of 89Sr or 90Sr, count the STS as soon as  practicable after
                                preparation to minimize the ingrowth of 90Y into the STS.
                     11.20.1.2.  If the presence of 89Sr can be excluded, total radiostrontium
                                will provide isotopic 90Sr results and the STS may be counted
                                at any time after  preparation.
            11.20.2. Calculate  the total  radiostrontium (90Sr) sample results using calculations
                     presented in Section 12.

12.  Data Analysis and Calculations
     12.1.  Calculation of Total Radiostrontium
            12.1.1.   When a sample is analyzed for total radiostrontium  (equivalent 90Sr), the
                     effective efficiency is calculated as follows:
                          Sr ~ &Sr90 ' V   ^        /~ £Y90                              (1)

              where

                 £xotai sr =  effective detection efficiency for total radiostrontium
                 £sr9o   =  final 90Sr detection efficiency
                 £Y9o   =  final 90Y detection efficiency
                 AY9o   =  decay constant for 90Y, 3.008x 10~6 s"1
                 t\     =  date and time of the Sr/Y separation
                 h     =  date and time of the midpoint of the count

                     Note: The elapsed time between the sample count and the reference date must be
                     calculated using the same time units as the decay constant.
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             12.1 .2.  The standard uncertainty of the effective efficiency is calculated as
                     follows:
            al Sr) =   '(^o) + l - e-^O?™) + 2l - e-^u(ssi90^90)       (2)

              where

                     ^ (.** Sr90 3 ^ Y90 )~  ^ \^ Sr90 ' ^ Y90 / ^ V^ Sr90 / ^ \^ Y90 /

                     Note: This term is derived during calibrations in Appendix A, Section 4.
90Sr is calculated as follows:
             12.1.3.  The total radiostrontium activity concentration (^Ciotai sr) equivalent to
                                        follows
                                         7? — 7?
                         Total Sr

                     where

                         £)F = e"^90^1"'^                                              (4)
                     and where
                         RH       =  beta gross count rate for the sample (cpm)
                         Rb       =  beta background count rate (cpm)
                         stotai sr   =  effective efficiency of the detector for total strontium
                                     referenced to 90Sr
                         Y        =  fractional chemical yield for strontium
                         V        =  volume of the sample aliquant (L)
                         DF      =  correction factor for decay of the sample from its
                                     reference date until the midpoint of the total strontium
                                     count
                         Asr9o      =   decay constant for 90Sr, 7.642x 1(T10 s"1
                         t0        =  reference date and time for the sample
                         h        =  date and time of the Sr/Y separation

                     Note: The elapsed time between the sample count and the reference date must be
                     calculated using the same time units as the decay constant

             12.1 .4.  The standard counting uncertainty of the total radiostrontium activity
                     concentration, WccC^Cxotai sr) is calculated as follows:
                     McC \AL Total Sr) ~
                                              t,    ^
                                     2.22xsTotalSlxYxVxDF
                                                                (5)
              where:
                         4        =  Duration of the sample count (min)
                         t\,        =  Duration of the background subtraction count (min)
                                    90
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          Total Radiostrontium (90Sr) in Water: Rapid Method for High-Activity Samples
            12.1.5.  The combined standard uncertainty (CSU) for the total radiostrontium
                    activity concentration, z/cC^Crotai sr), is calculated as follows:
              U(AC    } ~   2 (AC    } + AC2     1*™*
              Mc^UTotalSr^ ~, PcC ^U Total Sr J + ^U Total Sr     2       +
                                                      ^Total Sr
             where:
                 w(Y)   =  standard uncertainty of fractional chemical yield for strontium
                        =  standard uncertainty of the volume of the sample aliquant (L)
            12.1.6.  If the critical level concentration (Sc) or the minimum detectable
                    concentration (MDC) are requested (at an error rate of 5%), they can be
                    calculated using the following equations:3
             0.4 x p- -1 + 0.677 x  1 + ^ +1.645 x  l(Rb tb + 0.4)x ^- x  1 + ^
                  Vb    j         (.   lb)         V             tb   (.   tb.
                               tsx2.22xsTotalSlxYxVxDF
                    MDC =
                                                  rrt
                                 tsx2.22xsTotalSlxYxVxDF
(8)
     12.2.   Chemical Yield for Strontium
            12.2.1.   Calculate the chemical yield for strontium using the gravimetric data
                    collected in Step 11.18:


                    Y=7v"TcV                                               (9)
                    where:
                        Y       =   strontium yield, expressed as a fraction
                        ms      =   mass of Sr(NC>3)2 recovered from the sample (g)
                        ^sr(No3)2 =   gravimetric factor for strontium weighed as the nitrate,
                                    414.0mgSr/gSr(NO3)2
                        cc       =   Sr mass concentration in the strontium carrier solution
                                    (mg/mL)
                        FC      =   volume of strontium carrier added to the sample (mL)
                        cn       =   Sr mass concentration native to the sample - if
                                    determined (mg/L)
                        V       =   volume of sample aliquant (L)
            12.2.2. Calculate the standard uncertainty of the yield as follows:
3 The formulations for the critical level and minimum detectable concentration are based on the Stapleton
Approximation as recommended in MARLAP Section 20A.2.2, Equations 20.54 and 20A.3.2, and Equation 20.74,
respectively. The formulations presented assume a = 0.05, ft = 0.05 (with Z!_a = Z!_P = 1.645), and d = 0.4.


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          Total Radiostrontium (90Sr) in Water: Rapid Method for High-Activity Samples
                                                                     (10)
                                  f,+c»
where
       u(-)     =    standard uncertainty of the quantity in parentheses,
                                                                      eses.
                     u(-)     =    standard uncertainty of the quantity in parentheses,
                     Mr(-)     =    relative standard uncertainty of the quantity in parenthe
     12.3.   Results Reporting
            12.3.1.  Unless otherwise specified in the APS, the following items should be
                    reported for each result:
                    12.3.1.1.   Result for total radiostrontium (Step 12. 1 .3) in scientific
                               notation ± 1 combined standard uncertainty.
                    12.3.1.2.   Volume of sample aliquant and any dilutions used.
                    12.3.1.3.   Yield of tracer and its uncertainty.
                    12.3.1.4.   Case narrative
                    12.3.1.5.   The APS may specify reporting requirements for samples
                               originating from an RDD or other event where intractable
                               material (e.g., strontium titanate) may be present. If specific
                               guidance is not provided, but intractable materials are likely
                               present in samples, the results for soluble strontium (from the
                               aqueous phase) should be reported per Step  12.3.2.
            12.3.2.  If solid material was filtered from the solution and analyzed separately, the
                    gross beta results from the direct count of filtered solids should be
                    calculated as "gross beta (90Sr)" or "gross beta equivalent 90Sr" and
                    reported separately in terms of pCi/L of the original volume of sample.
                    For Example:
                    90Sr for Sample 12-1-99:
                        Filtrate result:                       (1.28 ± 0.15)xl01pCi/L
                        Gross beta (90Sr) filtered residue result: (2.50 ± 0.30)xlO° pCi/L

  13. Method Performance
     13.1.   Results of method validation performance are to be archived and available for
            reporting purposes.
     13.2.   Expected turnaround time per sample or per batch (See Figure 17.4 for typical
            processing times (assumes samples are not from RDD).
            13.2.1. Preparation and chemical separations for a batch of 20 samples can be
                    performed by using two vacuum box systems (12 ports each).
                    simultaneously, assuming 24 detectors are available. For an analysis of a
                    500 mL sample aliquant, sample preparation and digestion should take
                    -3-4 h.
            13.2.2. Purification and separation of the strontium fraction using cartridges and
                    vacuum box system should take -0.5-1.2 h.
            13.2.3. Sample test source preparation takes -0.75 - 1.5 h.
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            13.2.4. A 100-minute counting time is sufficient to meet the MQO listed in Step
                    9.2, assuming 0.5 L aliquant, a background of 1 cpm, detector efficiency
                    of 0.3-0.4, and radiochemical yield of at least 0.5.
     13.3.  Total radiostrontium (90Sr) data reduction should be achievable between 6  and 9
            hours after the beginning of the analysis.
     13.4.  The sample may be recounted following a delay of 1-21 days to verify the
            radiochemical purity of 90Sr. If the source contains pure 90Sr, the total
            radiostrontium activity calculated from the two counts should agree within the
            uncertainty of the measurements. Minimizing the time between the chemical
            separation of Sr and the initial count, longer count times, and increasing the delay
            between the two counts, will minimize the overall uncertainty of the data and
            provide more sensitive and reliable measures of the radiochemical purity of the
            STS.

            Note: The 89Sr and 90Sr may be determined from two consecutive counts of the source -
            calculations are presented in Appendix B. This approach must be validated prior to use.

14.  Pollution Prevention
     14.1.  The use of Sr-Resin™ reduces the amount of acids and hazardous metals that would
            otherwise be needed to co-precipitate and purify the sample and prepare the final
            counting form.

15.  Waste Management
     15.1.  Nitric acid  and hydrochloric acid wastes should be neutralized before disposal and
            then disposed in accordance with prevailing laboratory, local, state and federal
            requirements.
     15.2.  Initial column effluents contain mg/mL levels of barium and should be disposed in
            accordance with prevailing laboratory, local, state and federal requirements.
     15.3.  Final precipitated materials may contain radiostrontium and should be treated as
            radioactive waste and disposed in accordance with the restrictions provided in the
            facility's radioactive materials  license and any prevailing local restrictions.
     15.4.  Used resins and columns should be considered radioactive waste and disposed of in
            accordance with restriction provided in the facility's radioactive materials license
            and any prevailing local restrictions.

16.  References
     16.1.  SRW04-11, "Strontium 89, 90  in Water," Eichrom Technologies, Inc., Lisle,
            Illinois (February 2003).
     16.2.  "Rapid Column Extraction Method for Actinides and  89/90Sr in Water Samples,"
            S.L. Maxwell III. Journal of Radioanalytical and Nuclear Chemistry 267(3):  537-
            543 (Mar 2006).
     16.3.  U.S. Environmental Protection Agency (EPA). 2009. Method Validation Guide for
            Radiological Laboratories Participating in Incident Response Activities. Revision
            0. Office of Air and Radiation, Washington, DC. EPA 402-R-09-006, June.
            Available at:www.epa.gov/narel/incident  guides.html.
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         Total Radiostrontium (90Sr) in Water: Rapid Method for High-Activity Samples
     16.4.  Multi-Agency Radiological Laboratory Analytical Protocols Manual (MARLAP).
           2004. EPA 402-B-1304 04-001A, July. Volume I, Chapters 6, 7, 20, Glossary;
           Volume II and Volume III, Appendix G. Available  at: www.epa.gov/radiation/
           marlap/index.html.
     16.5.  ASTM D7282 "Standard Practice for Set-Up, Calibration, and Quality Control of
           Instruments Used for Radioactivity Measurements," ASTM Book of Standards
           11.02, current version, ASTM International, West Conshohocken, PA.
     16.6.  SR-04, "Radiochemical Determination of Radiostrontium in Water,  Sea Water, and
           Other Aqueous Media," Eastern Environmental Radiation Facility (EERF)
           Radiochemistry Procedures Manual, Montgomery,  AL, EPA 520/5-84-006 (August
           1984).
     16.7.  ASTM Dl 193, "Standard Specification for Reagent Water," ASTM Book of
           Standards 11.02, current version, ASTM International, West Conshohocken, PA
     16.8.  Nuclear data from NUDAT 2.3 and the National Nuclear Data Center at
           Brookhaven National Laboratory; available at www.nndc.bnl.gov/nudat2/indx_
           dec.isp, database version of 6/30/2009.
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          Total Radiostrontium ( Sr) in Water: Rapid Method for High-Activity Samples
17.  Tables, Diagrams, Flow Charts and Validation Data
     17.1.   Validation Data

            This section intentionally left blank.

     17.2.   Nuclide Decay and Radiation Data

       Table 17.1. Decay and Radiation Data
Nuclide
90Sr
90y
89Sr
Half-life
(days)
1.052E+04
2.6667
50.53
X
(s-1)
7.642xlO"10
3.005xlO"6
1.587X10'7
Abundance
1.00
1.00
1.00
Pmax
(MeV)
0.546 MeV
2.280 MeV
1.495 MeV
ftavg
(MeV)
0.196 MeV
0.934 MeV
0.585 MeV
     17.3.   Ingrowth and Decay Curves and Factors

                             In-Growth Curve for 90Y in 90Sr
                         100
 200        300        400        500
 Time Elapsed After Sr-90 Separation (h)
^^^—Y-90 	Sr-90 • • • Beta Activity
600
700
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           Total Radiostrontium (  Sr) in Water: Rapid Method for High-Activity Samples
Table 17.2. Total Beta Activity Ingrowth Factors for 90Y in 90Sr
Ingrowth time elapsed (hours)
Factor
Ingrowth time elapsed (hours)
Factor
0.25
0.003
^mmmimsfffi
144
0.790
2
0.021
>if|f:if{i|i«i««|
192
0.875
4
0.042
240
0.926
12
0.122
320
0.969
24
0.229
400
0.987
48
0.405
480
0.994
72
0.541
560
0.998
96
0.646
640
0.999
Factor = (  Y activity/ Sr activity at zero hours of ingrowth)
       o  0.5 -
                                                       89r
                                     Decay Curve for  Sr
                       100        200        300       400
                                       Time Elapsed since collection (h)
                                             — Sr-89 Activity
                           500
600
700
                                                              89r
                               Table 17.3. Decay Factors for aySr
Decay time elapsed (hours)      0.25       2
Factor                       1.000    0.999
Decay time elapsed (hours)      144      192
Factor                       0.921    0.896
        4        12       24       48       72       96
       0.998    0.993    0.986    0.973    0.960     0.947
       240      320      400      480      560     640
       0.872    0.833    0.796    0.760    0.726     0.694
Factor = (89Sr activity/89Sr activity at zero hours of ingrowth)
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         Total Radiostrontium ( Sr) in Water: Rapid Method for High-Activity Samples
                             89C	j 90C
     17.4.  Decay Schemes for sySr and yuSr
                            "Sr and 9°Sr Decay Scheme
                      t,,= 50.53 d
                                                       p = 0.55 MeV
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             Total Radiostrontium (  Sr) in Water: Rapid Method for High-Activity Samples
       17.5.    Process Flow with Typical Processing Times (assumes no filtration necessary)
     Elapsed
      Time
       Hrs

       1.0


       3.0



       3.5




       4.0
       4.5
       5.5
       6.0
       8.7
      27-90
Aliquant sample, add HN03 to pH <2; Add Sr
       and Ba carriers (11.1 -11.2)
                                                       Heat sample (11.3)
                                            Add indicator and adjust to phenolphthalem
                                                   endpoint with NaOH (11.4)
Add Na2CQ3 to precipitate; Digest and allow to
      cool; Settle/centrifuge (11.5-11.6)
                                       May
                                   intractable Sr
                                    be present?
                                       (11.8)
                                                            ndissolved
                                                             residue
                                                            present?
                                                             (11.10)
                Cover and digest
                 sample for 30
                    minutes
               Continue with 11.10
                    (11.8)
                        Load sample onto prepared
                          column at £1 rnUmin.
                                (11.13)
                                Prepare and
                             precondition column
                             with 5 ml_8M HN03
                                (11.11-11.12)
                 Analyze filter for
                   gross beta.
                 Evaluate results
                   against 9DSr
                 Screening ADLs.
                     (11.10)
                                 Sr Resin
                                 Column
                                                                       Adjust flow to S3 rnL/min. Rinse
                                                                    centrifuge tube with three 3-mL rinses of
                                                                   8 M HN03 adding each to column (11.14)
                                                   If Ce, Ru, Pu.or Np may be present, strip
                                                   with 10 mLHN03/oxalic reagent (11.15)
                                                                    twoSM HN03 rinses. Record t, (11.16)
                                                   Replace tube to retain eluate. Adjust flow
                                                    to £1 mUmin. Elute Sr with two 5 ml
                                                    portions of0.05MHN03 (11.17-11.18)
                                         Retain Sr eluate (11.17-11.18)
                                                         Discard precondition (11.12),
                                                        load (11.13) and strip and rinse
                                                           (11.14-11.16) effluents
               Quantitatively transfer and evaporate Sr eluate onto clean, tared planchet (11.19.1-11.19.4)
                     Dry to constant mass and weigh to determine chemical yield (11.19.5-11.19.6)
     Beta Count with Gas Flow Proportional Counter to determine Total Sr activity
                              (11.20.1-11.20.2)
                                   Recount to verify for MSr if required by APS
                                               (11.20.1-11.20.2)
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          Total Radiostrontium (90Sr) in Water: Rapid Method for High-Activity Samples
                                       Appendix A
                     Method and Calculations for Detector Calibration
                                                                        90C
Al .The effective detection efficiency for total radiostrontium (referenced to  Sr) is calculated as
   the weighted sum of the 90Sr and 90Y efficiencies that reflects the relative proportions of 90Y
   and 90Sr based on the 90Y ingrowth after strontium separation.

   Note: While 89Sr efficiency calibration is not needed unless 89Sr analysis will be performed, instructions
   for preparation are provided to support the two count approach should this option be desired.

     ALL  Due to the low mass of carrier used for this method, self-absorption effects may be
            assumed to be constant. Calibrate each detector used to count samples according to
            ASTM  Standard Practice D7282, Section 16, "Single Point Efficiency or Constant
            Test Mass for a Specific Radionuclide" and the instructions below.
     A1.2.  Prepare a blank and at least three working calibration sources (WCS) for 90Sr and
            90Y, and 89Sr (if needed) as follows:
            Al .2.1.  The 90Sr and 89Sr radioactive standard solutions used to prepare WCSs
                     shall be traceable to a national standards body such as NIST and shall
                     originate from a standards supplier (or lot) different from standards used
                     for calibration verification and batch quality controls. The standards
                     should be diluted in nitric acid.
            Al.2.2.  The planchets used for the sources shall be of the same size, materials and
                     type as those used for the analysis of STSs.
            Al.2.3.  Preparation of 89Sr WCSs (if needed): 89Sr standard solution (in 0.5-M
                     HNOs) is evaporated to dryness in a stainless steel planchet as follows:
                     Al.2.3.1. For each 89Sr WCS to be prepared, and for the associated
                               blank, add a strontium carrier to 10 mL of 0.05-M HNOs in a
                               disposable 50-mL centrifuge tube. The amount of carrier
                               should be adjusted to approximate the amount expected to be
                               recovered from routine samples.

                               Note: If the average recovery has not been determined, the laboratory
                               may assume 85% chemical yield for determining the amount of carrier
                               to use in Step 1.2.3.1.

                               Note: If the 89Sr standard contains residual chloride, it will attack the
                               surface of the planchet and compromise the quality of the calibration
                               standard. In such cases, convert the aliquant of standard solution to a
                               nitrate system by adding 1 mL concentrated HNO3 and taking to
                               dryness 2 times prior to quantitatively transferring the solution to the
                               planchet.

                     Al.2.3.2. For each WCS, add a precisely known amount of traceable 89Sr
                               solution to a 50-mL centrifuge tube. Sufficient activity must be
                               present at the point of the count to permit accumulation of
                               greater than  10,000 net counts  in a counting period deemed to
                               be reasonable by the laboratory. The minimum activity used,
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          Total Radiostrontium (90Sr) in Water: Rapid Method for High-Activity Samples
                               however, should produce WCS count rates at least 20 times the
                               background signal but not greater than 5000 cps.
                    Al .2.3.3.   Mix the solution and quantitatively transfer each WCS and the
                               blank to respective clean stainless steel counting planchets
                               using three rinses of 0.05-M HNOs.
                    Al .2.3.4.   Evaporate to dryness using the same techniques used for
                               sample test sources.
                    Al.2.3.5.   For each detector to be calibrated, count three 89Sr WCSs for
                               sufficient time to accumulate at least 10,000 net counts.

   Al .3.  Preparation of 90Sr and 90Y WCSs:  Separate WCSs for 90Sr and 90Y are prepared by
          chemically separating 90Y from a standard solution of 90Sr.
          Al .3.1.   For each 90Sr WCS to be prepared, and for the associated blank, add 1 mL of
                   5 mg/mL strontium carrier to a disposable 50-mL centrifuge tube. The
                   amount of carrier added should correspond to that expected to be recovered
                   from a routine sample.

                   Note: If the average recovery has not been determined, the laboratory may assume
                   85% chemical yield for determining the amount of carrier to use for Step 1.3.1.

          Al.3.2.   For each 90Sr WCS, add a precisely known amount of traceable 90Sr solution
                   to a 50-mL centrifuge tube. Sufficient activity should be present at the point
                   of the count to permit accumulation of greater than 10,000 90Sr and  10,000
                   90Y net counts in the respective sources in a counting period deemed to be
                   reasonable by the laboratory. The minimum activity used, however  should
                   produce WCS count rates at least 20 times the background signal but not
                   greater than 5000 cps.
          Al .3.3.   Set up one Sr Resin column for each 90Sr WCS and for the associated blank.
                   Condition each column with 5 mL  of 3-M FINOs. Column effluents are
                   discarded to waste.
          Al .3.4.   Place a clean centrifuge tube under each column to catch all combined 90Y
                   effluents.

                   Note: Unless otherwise specified in the procedure, use a flow rate of ~ 1 mL/min for
                   load and strip  solutions and ~ 3 mL/min for rinse solutions.

          Al.3.5.   Load the 90Sr solution onto the column. The load solution effluent
                   containing 90Y is retained.
          Al .3.6.   Rinse the centrifuge tube with three successive 2-mL portions of 3-M FINOs
                   adding each of the rinses to the column after the previous rinse has reached
                   the upper surface of the resin. These effluents also contain 90Y and are
                   retained.
          Al .3.7.   Rinse the column with 5 mL of 3 M FINOs  and retain the column  effluents
                   containing 90Y. Record the date and time that the final rinse solution leaves
                   the column to the nearest 5 minutes as ti, "Time of 90Y Separation." Remove
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          Total Radiostrontium (90Sr) in Water: Rapid Method for High-Activity Samples


                   the centrifuge tube that has the combined 90Y effluents. Place a clean tube
                   under the column to catch the strontium eluate in subsequent steps.

                   NOTE: From this point, 90Sr must be eluted, and the 90Sr WCS must be prepared and
                   counted as expeditiously as possible to minimize 90Y ingrowth and necessary
                   corrections to the efficiency. Counting of the 90Sr WCS should be completed, if
                   possible, within 3-5 hours but no longer than 10 hours from the time of 90Y
                   separation. If processing or counting capacity is limited, concentrate resources on 90Sr
                   WCS and counting first. The 90Y WCS are not compromised by ingrowth but must
                   only be counted promptly enough to minimize decay and optimize counting statistics.

          Al.3.8.  Strip strontium from each column by adding 10  mL of 0.05-M HNOs to
                   each column, catching the effluents containing 90Sr in the centrifuge tube.
          Al .3.9.  Quantitatively transfer 90Sr and 90Y fractions to respective tared planchets
                   using three portions of 0.05-M HNOs.
          Al.3.10. Evaporate to dryness using the same techniques used for sample test
                   sources.

                   Note: Gravimetric measurements may be performed following the counting to
                   minimize elapsed time between separation and counting.

   Al .4.  Weigh the 90Sr and 90Y WCS sources and calculate the net residue mass.
          Al .4.1.  The net mass of the strontium nitrate precipitate shall indicate near
                   quantitative yield of strontium of 95-103%. If strontium yield falls outside
                   this range, determine and address the cause for the losses and repeat the
                   process. The known activity  of 90Sr in the standard is corrected for losses
                   based on the measured chemical yields of the strontium carrier.

                   Note that no correction shall be applied for values greater than 100% because this will
                   produce a negative bias in the calibrated efficiency.

          Al .4.2.  The net residue mass of the 90Y should be equivalent to that of the
                   associated blank (i.e., -0.0 mg). Higher residue mass may indicate the
                   breakthrough of strontium and will result in high bias in the 90Y efficiency.
                   If blank corrected net residue mass exceeds 3%  of the strontium carrier
                   added, determine and address the cause for the elevated mass and repeat the
                   process.
          Al .4.3.  Count three 90Sr WCS on each detector to be calibrated, for sufficient time
                   to accumulate at least 10,000 net  counts.
          Al .4.4.  Count three 90Y WCS on each detector to be calibrated, for sufficient time to
                   accumulate at least 10,000 net counts.
          Al .4.5.  Count the associated blanks as a gross contamination check on the process.
                   If indications of contamination are noted, take appropriate corrective actions
                   to minimize spread and prevent cross-contamination of other samples in the
                   laboratory.
   Al .5.  Verify the calibration of each detector according to ASTM Standard Practice D7282,
          Section 16, and the laboratory quality  manual and standard operating procedures.


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          Total Radiostrontium (90Sr) in Water: Rapid Method for High-Activity Samples


   Al .6.   Calculations and data reduction for 90Sr and 90Y calibrations and calibration
           verifications are presented in Sections A2, A3, and A4. Calculations for total
           radiostrontium are in Section 12.

A2. Calculation of Detection Efficiency for 90Sr
   A2. 1 .   Calculate the following decay and ingrowth factors for each WCS:

              DFs = e-**90^                                                       (Al)
              JFY90=l-e-A™fe-'l)                                                      (A2)

              where
                 DFS   =   decay factor for decay of the90 Sr standard from its reference date
                            until the 90Sr/90Y separation
                 7FY90  =   ingrowth factor for ingrowth of 90Y after the 90Sr/90Y separation
                 ASr9o   =   decay constant for 90Sr, 7.642x 1(T10 s"1
                 AY9o   =   decay constant for 90Y, 3.005x 10~6 s"1
                 to     =   reference date and time for the 90Sr standard
                 t\     =   date and time of the Sr/Y separation
                 h     =   date and time of the midpoint of the 90Sr count

              Note: The elapsed time between the sample count and the reference date must be calculated
              using the same time units as the decay constant

   A2.2.   Calculate the 90Sr detection efficiency for each WCS:
                     K   — K                              K
       f,    - _ s->    b __ 777    y?   - _ li __ 7/7    yp
       6Sr90,i ~~ ,^>       T^    ^.^    il Y90,z A 6Y90 ~ A ^       T^   7-.^    •" Y90,z A 6Y90
                              .          ,
                  r0 std X   X    .,,                    Sr90 ,td X  ,

              where
                 esr9o,!      =   9°Sr detection efficiency for the 7th WCS
                  eY90       =   average 90Y detection efficiency (from Step A3. 2)
                 Rs,i        =   beta gross count rate for the /'th WCS (in cpm)
                 R\,        =   background count rate, in cpm
                 Rn,t        =   beta net count rate for the 7th WCS (cpm)
                 ACsr9o std  =      activity concentration of the 90Sr standard solution on its
                                reference date (cpm/mL or cpm/g)
                  FS;;        =   amount (volume or mass) of the standard  solution added to the
                                7th WCS
   A2.3.  Average the efficiencies determined in Step A2.2 for all the WCSs to obtain the final
          detection efficiency for 90Sr.
               Sr90 ~  Sr90
                           1  "
                         = -Ye
                           wZ-i  sr90,i

              where
                 eSr9o,/-      =  9°Sr detection efficiency determined for the 7th WCS in A2.2,
                 77         =  number of WCSs prepared and counted.


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          Total Radiostrontium (90Sr) in Water: Rapid Method for High-Activity Samples
   A2.4.  Calculate the standard uncertainty of the average 90Sr detection efficiency as follows


                                                    0 std)
            where

                   = — Y /FY90 , = average value of  Y ingrowth factors                 (A6)
                     n ,=i
            and
              u(-}     =    standard uncertainty of the value in parentheses,
              z/r(-)    =    relative standard uncertainty of the value in parentheses.

A3. Detection Efficiency for 90Y
   A3 . 1 .  Calculate the 90Y detection efficiency, 6^90,;, for each WCS,
               Y90,!
                        Sr90 std S,i    !,,i      Sr90 std
       where
              DFsi = e^r9o(^o) e"^90^"^                                             (A8)
       and
            £y9o,i       =  9°Y detection efficiency determined for the WCS
            Rs,i        =  beta gross count rate for the /'th WCS (cpm)
            Rb         =  background count rate, in cpm
            Rn,t        =  beta net count rate for the / WCS (cpm)
            ACsr90std   =  activity concentration of the 90Sr standard solution on its reference
                          date (dpm/mL or dpm/g)
            V^i        =  amount of the standard solution added to the /th WCS (mL or g)
            DFSj       =  combined correction factor for decay of the 90Sr standard in the /'th
                          WCS from its reference date until 90Y separation, and for the decay
                          of 90Y from its separation until the midpoint of the count
            Asr9o       =  decay constant for 90Sr, 7.642x 1(T10 s"1
            AY9o        =  decay constant for 90Y, 3 .005 x 1 (T6 s"1
            to          =  reference date and time for the 90Sr standard
            t\          =  date and time of the90 Y separation
                                                            on
            h          =  date and time at the midpoint of the  Y count

       Note: The elapsed time between the sample count and the reference date must be calculated using the
       same time units as the decay constant

   A3. 2.  Average the efficiencies determined  in Step A3.1 to obtain the final detection
          efficiency for 90Y.
                                         _     1
                                  £Y90  ~  S Y90  ~
where

     n          = number of WCS prepared and counted
                       = 9°Y detection efficiency determined for the /'th WCS in Step A3. 1
                                   90
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          Total Radiostrontium (Sr) in Water: Rapid Method for High-Activity Samples
   A3 .3 .  The combined standard uncertainty of the average efficiency for 90Y including
          uncertainty associated with the preparation of the calibration standards is calculated
          as follows:
                                                                                   (A10)
              where
              u(-)
                            standard uncertainty of the value in parentheses,
                            relative standard uncertainty of the value in parentheses.
                                                           90
                                                                                90
A4. Calculate the covariance and correlation coefficient for the  Sr efficiency and the  Y
   efficiency:

              «(%90^Y9o) = SsmeYgo

       and
                                                                                   (Al 1)
       where
              u(-,-)
              r(-,-)

              u(-)
              ur(-)
                          u(esm)u(eY90)


                            estimated covariance of the two quantities in parentheses,
                            estimated correlation coefficient of the two quantities in
                            parentheses,
                            standard uncertainty of the quantity in parentheses,
                            relative standard uncertainly of the quantity in parentheses.
A5. Detection Efficiency for 89Sr (if needed for Appendix B Calculations)
   A5. 1.  Calculate the detection efficiency, esr89,;, for each WCS as follows:
                                                                                   (A13)
       where
       and
              DF  =
                                          (A14)
                                                          'th
                    std
              t0
                             Sr detection efficiency for the /'t WCS
                            beta gross count rate for the /'th WCS (cpm)
                            background count rate, in cpm
                            activity concentration of the 89Sr standard solution on the reference
                            date (dpm/mL or dpm/g)
                            am ount (volume or mass) of the standard solution added to the /th
                            WCS (mL or g)
                            correction factor for decay of the 89Sr standard for the /'th WCS
                            from its reference date until the midpoint of the sample count
                            decay constant for 89Sr, 1 .372x 10"2 d"1
                            reference date and time for the 89Sr standard
                            date and time at the midpoint of the 89Sr count
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          Total Radiostrontium (90Sr) in Water: Rapid Method for High-Activity Samples
       A5.1.1. Average the efficiencies determined in Step A5.1 to obtain the final detection
              efficiency for 89Sr.
                                                i  n


              where
                 £sr89,/ =    89Sr detection efficiency determined for the /'th WCS in Step A5.1,
                 n    =    number of WCSs prepared and counted.

       A5.1.2.The combined standard uncertainty of the average efficiency for 89Sr including
              uncertainty associated with the preparation of the calibration standards is
              calculated as follows:
                                             + 489«r2(^C'sr89std)                        (Al6)
              where
                 u(-)  =    standard uncertainty of the value in parentheses,
                 wr(-)  =    relative standard uncertainly of the value in parentheses.
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          Total Radiostrontium (90Sr) in Water: Rapid Method for High-Activity Samples
                                      Appendix B:
                      Calculations for Isotopic 89Sr and 90Sr Results

A numerical approach for determining 89Sr and 90Sr activity from a single sample is performed
by a number of laboratories. This presentation, however, allows a more rigorous evaluation of
uncertainties than commonly employed. Lacking this treatment, many labs have found that the
traditional approach (evaluating counting uncertainty for a single count only) has led to
overestimation of the quality of results, and to poor decisions regarding the presence or absence
of low activities of one radioisotope of strontium in the presence of elevated activities of the
second.

These calculations may be valuable to laboratories who wish to determine isotopic 89Sr and 90Sr
in a large number of samples with a minimum of additional effort beyond the initial preparation
and counting of total radiostrontium. Specifically, it involves performing a second count of the
same radiostrontium sample test source (STS) and mathematically resolving the activity of the
two isotopes. Although the STS may be recounted as soon as 1-2 days after the initial count,
resolution is optimized if the two counts span as large a range of the 90Y ingrowth as practicable.
The time elapsed between the chemical separation and the first count should be minimized, while
the second count should optimally proceed as 90Y approaches secular equilibrium with 90Sr but
before significant decay of 89Sr has occurred, for example, after 3-5 half-lives of 90Y have
elapsed (1-2 weeks).

This section may not be employed without complete validation of the approach by the
laboratory, including testing with samples containing ratios of 90Sr relative to 89Sr varying from
pure 90Sr to pure  89Sr.

Bl.The equations in this section are used to calculate the 90Sr and 89Sr activity  of a sample from
   data generated from two successive counts of the same radiostrontium sample test source.
   B 1 . 1 .  For each of the two counting measurements (/' = 1 , 2), calculate the following decay
          and ingrowth factors:

                       e-^'-^                                                  (Bl)
                       e-"-w                                                  (B2)
              77    _
              /Y90,z ~

          where:
              DFsrs9,i  =    decay factor for decay of 89Sr from the collection date to the
                           midpoint of the /th count of the STS
              DFSr9o,i  =    decay factor for decay of 90Sr from the collection date to the
                           midpoint of the /'th count of the STS
                      =    combined decay and ingrowth factor for decay of 90Sr from the
                           collection date to the Sr/Y separation and ingrowth of 90Y from the
                           separation to the midpoint of the /'th count of the STS
                       =   decay constant for 89Sr = 1.58?x 1(T7 s"1
                       =   decay constant for 90Sr = 7.642x 1(T10 s"1
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          Total Radiostrontium (90Sr) in Water: Rapid Method for High-Activity Samples
              t0        =   collection date and time for the sample
              4eP      =   date and time of the Sr/Y separation
              tj        =   date and time of the midpoint of the /'th count of the STS

          Note: The elapsed time between the sample count and the reference date must be calculated
          using the same time units as the decay constant

   B1.2.  For / = 1,2, use the results from Section A5.1 in Appendix A to calculate the
          following sensitivity factors:
                         sSim                                                      (B4)
          where
                at        =  sensitivity of the count rate in the 7th measurement to 89Sr activity,
                bt        =  sensitivity of the count rate in the /'th measurement to 90Sr activity.
                SY9o,i     =  90Y efficiency of the detector for the /'th count of the STS,
                esr9o,z     =  9°Sr efficiency of the detector for the /'th count of the STS.
   B1.3.  Calculate the standard uncertainties of the sensitivity factors using the equations:
                            u(sSl^                                                (B6)
                                                                                    (B7)
          where the estimated covariance of the 90Sr and 90Y efficiencies is calculated as
          follows:
                f          \    f          \f\f\                          /T> O \

          and where the estimated correlation coefficient r(eSr9o,z, £Y9o,0 was determined during
          the calibration.

   B1.4.  Calculate the covariances u(ai,a2) and u(b\^>^) as follows:

                       u(a^ )u(a2),        if only one detector is used


                       ala2 wr2 G4CSr89 std),  if two detectors are used
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          Total Radiostrontium (Sr) in Water: Rapid Method for High-Activity Samples
 u(bl,b2} =
            Sr90,r Y90.2 ~*~ ^^Sr90,r ¥-90,1/^(^90,1' S Y90,l)
                                      ,^9o,2u2(s^o,il   usingonly one detector    (BIO)
                                                      usingtwo detectors
              2 wr2 G4CSr90std),
                                                      89
   where
                     =  activity concentration of the 5ySr standard used for calibration
                     =  activity concentration of the 90Sr standard used for calibration
            Mr(-)     =  relative standard uncertainty of the quantity in parentheses
B1.5.  For / = 1,2, calculate the net beta count rates, Rn^ and their standard uncertainties:

                                                                                   (B12)
       where:
            Ra
                        =   net beta count rate for the /th count of the STS (cpm)
                        =   beta gross count rate for the /'th count of the STS (cpm)
                        =   beta background count rate for the /'th count of the STS (cpm)
                        =   sample count time for the 7th count of the STS (min)
                        =   background count time for the /'th count of the STS (min)
                                                               89
                                                                       90
B1.6.  Using the values calculated in A5.1 - A5.5, calculate the  Sr and  Sr activity
       concentrations:

           AC=        ~
              SIS9
              Sr89
                   2.22xXxVxY
                   2.22xXxVxY
   where:
             = alb2-a2bl
                                                                                   (B13)
                                                                                   V    }

                                                                                   (B 14)


                                                                                   (B15)
       and where:
                2.22     =   conversion factor from dpm to pCi
                Y       =   chemical yield for strontium
                V       =   sample volume (L)
B2. The standard counting uncertainties for 89Sr (ueC(AC^9) ) and 90Sr (wcC(y4CSr90) ) are
    calculated in units of pCi/L as follows:
    urC (A CSrSq ) =
     ccv    Sr897
                        222xXxVxY
                                                                                   (B 1 6)
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                             ,90
          Total Radiostrontium (  Sr) in Water: Rapid Method for High-Activity Samples
                        2.22xXxVxY
                                                                                 (B17)
                                                       90C
B3.The combined standard uncertainties (CSU) for  Sr and  Sr are calculated as follows:
                               u\V)   u2(Y}  b22u2(al) + b2u2(a2)-
                                                                                 (B18)
                           2
                       ' -^l^Q
                           2
                                       y (b2 ) - 2b1b2 u(b, , b2
                                                            1/2
                           2  a22u2 (aj) + afw2 (a2) - 2ala2 u(^, a2
                             9               7^2
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   Total Radiostrontium (Sr-90) in Water: Rapid Radiochemical Method for High-Activity Samples
Appendix C:
Composition of Atlanta Drinking Water Used for this Study
Metals by ICP-AES
Silicon
Aluminum
Barium
Calcium
Iron
Magnesium
Potassium
Sodium
Inorganic Anions
Chloride
Sulfate
Nitrogen, Nitrate (as N)
Carbon Dioxide
Bicarbonate Alkalinity
Carbonate Alkalinity
Radionuclide
Uranium 234, 235, 238
Plutonium 238, 239/240
Americium 24 1
Strontium 90
Radium 226***
Concentration (mg/L)*
3.18
<0.200
0.0133
9.38
<0.100
<0.500
<0.500
<0.500

12.7
15.6
1.19

23.8
<3.00
Concentration (pCi/L)**
<0.01,<0.01,<0.01
<0.02, <0.02
<0.02
<0.3
0.11 ±0.27
-0.30 ±0.45
           Note: Analyses conducted by independent laboratories.
           *   Values below the reporting level are presented as less than (<) values.
               No measurement uncertainty was reported with values greater than the "Reporting
               Level."
            **  Reported values represent the calculated minimum detectable concentration (MDC)
               for the radionuclide(s).
           *** Two samples analyzed. Expanded uncertainty (k=2) as reported by the laboratory.
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                                          www.epa.gov
                                         February 2010
                                            Revision 0
     Rapid Radiochemical Method for
         Isotopic Uranium in Water
for Environmental Restoration Following
         Homeland Security Events
            U.S. Environmental Protection Agency

               Office of Air and Radiation
             Office of Radiation and Indoor Air
       National Air and Radiation Environmental Laboratory
                 Montgomery, AL 36115

            Office of Research and Development
         National Homeland Security Research Center
                 Cincinnati, OH 45268

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                             ISOTOPIC URANIUM IN WATER:
                      RAPID METHOD FOR HIGH-ACTIVITY SAMPLES

1.  Scope and Application
   1.1.   The method will be applicable to samples where the source of the contamination is
         either known or unknown sample sources. If any filtration of the sample is performed
         prior to starting the analysis, those solids should be analyzed separately. The results
         from the analysis of these solids should be reported separately (as a suspended activity
         concentration for the water volume filtered), but identified with the filtrate results.
   1.2.   The method is specific for 238U, 235U, and 234U in drinking water and other aqueous
         samples.
   1.3.   This method uses rapid radiochemical separations techniques for determining alpha-
         emitting uranium isotopes in water samples following a nuclear or radiological
                                                              0 IS   T\ S      T\ A
         incident. Although the method can detect concentrations of   U,   U, and   U on the
         same order of magnitude as methods used for  the Safe Drinking Water Act (SDWA),
         this method is not a substitute for SDWA-approved methods for isotopic uranium.
   1.4.   The method is capable of satisfying a required method uncertainty for 238U, 235U, or
         234U of 2.6 pCi/L at an analytical action level of 20 pCi/L. To attain the stated
         measurement quality objectives (MQOs) (see  Section 9.3 and 9.4), a sample volume of
         approximately 200 mL and count time of at least  1 hour are recommended. The sample
         turnaround time and throughput may vary based on additional project MQOs, the time
         for analysis of the final counting form, and initial sample volume. The method must be
         validated prior to use following the protocols provided in Method Validation Guide for
         Qualifying Methods Used by Radiological Laboratories Participating in Incident
         Response Activities (EPA 2009, reference 16.5).
   1.5.   The method is intended to be used for water samples that are similar in composition to
         drinking water. The rapid uranium method was evaluated following the guidance
         presented for "Level E Method Validation: Adapted or Newly Developed Methods,
         Including Rapid Methods" in Method Validation Guide for Qualifying Methods Used
         by Radiological Laboratories Participating in Incident Response Activities (EPA 2009,
         reference 16.5) and Chapter 6 of Multi-Agency Radiological Laboratory Analytical
         Protocols Manual (MARLAP 2004, reference 16.6). The matrix used for the
         determination of uranium was drinking water from Atlanta, GA. See the Appendix for a
         listing of the chemical constituents of the water.
   1.6.   Multi-radionuclide analysis using sequential separation may be possible using this
         method in conjunction with other rapid methods.
   1.7.   This method is applicable to the determination of soluble uranium. This method is not
         applicable to the determination of uranium isotopes contained in highly insoluble
         particulate matter possibly present in water  samples contaminated as a result of a
         radiological dispersion device (ROD) event.

2.  Summary of Method
   2.1.   This method is based on the sequential elution of interfering radionuclides as well as
         other components of the matrix by extraction chromatography to isolate and purify
         uranium in order to prepare  the uranium for counting by alpha spectrometry. The
         method utilizes vacuum assisted flow to improve  the speed of the separations. Prior to
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     Isotopic Uranium (238U, 235U, and 234U) in Water: Rapid Method for High-Activity Samples
        the use of the extraction resins, a water sample is filtered as necessary to remove any
        insoluble fractions, equilibrated with 232U tracer, and concentrated by either
        evaporation or calcium phosphate precipitation. The sample test source (STS) is
        prepared by microprecipitation with NdF3. Standard laboratory protocol for the use of
        an alpha spectrometer should be used when the sample is ready for counting.

3.  Definitions, Abbreviations and Acronyms
   3.1. Analytical Protocol Specification (APS). The output of a directed planning process that
        contains the project's analytical data needs and requirements in an organized, concise
        form.
   3.2. Analytical Action Level (AAL). The term "analytical action level" is used to denote the
        value of a quantity that will cause the decisionmaker to choose one of the alternative
        actions.
   3.3. Analytical Decision Level (ADL). The analytical decision level refers to the value that
        is less than the AAL based on the acceptable error rate and the required method
        uncertainty.
   3.4. Discrete Radioactive Particles (DRPs or "hot particles"). Particulate matter in a sample
        of any matrix where a high concentration of radioactive material is contained in a tiny
        particle (um range).
   3.5. Multi-Agency Radiological Analytical Laboratory Protocol Manual (M ARL AP) (see
        Reference 16.6.)
   3.6. Measurement Quality Objective (MQO). MQOs are the analytical data requirements of
        the data quality objectives and are project- or program-specific and can be quantitative
        or qualitative. These analytical data requirements serve as measurement performance
        criteria or objectives of the analytical process.
   3.7. Radiological Dispersal Device (RDD), i.e., a "dirty bomb." This is an unconventional
        weapon constructed to distribute radioactive material(s) into the environment either by
        incorporating them into a conventional bomb or by using sprays, canisters, or manual
        dispersal.
   3.8. Required Method Uncertainty (WMR). The required method uncertainty is a target value
        for the individual measurement uncertainties, and is an estimate of uncertainty (of
        measurement) before the sample is actually  measured. The required method uncertainty
        is applicable below an Analytical Action level.
   3.9. Relative Required Method Uncertainty (
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     Isotopic Uranium (238U, 235U, and 234U) in Water: Rapid Method for High-Activity Samples
                 to enable radionuclide-specific measurements. This method separates these
                 radionuclides effectively. The significance of peak overlap will be determined
                 by the individual detector's alpha energy resolution characteristics and the
                 quality of the final precipitate that is counted.
   4.2. Non-Radiological: Very high levels of competing higher valence anions (greater than
        divalent such as phosphates) will lead to lower yields when using the evaporation
        option due to competition with active sites on the resin. If higher valence anions are
        present, the phosphate precipitation option may need to be used initially in place of
        evaporation. If calcium phosphate coprecipitation is performed to collect uranium (and
        other potentially present actinides) from large-volume samples, the amount of
        phosphate added to coprecipitate the actinides (in Step 11.1.4.3) should be reduced to
        accommodate the sample's high phosphate concentration.

5.  Safety
   5.1. General
        5.1.1.    Refer to your safety manual for concerns of contamination control, personal
                 exposure monitoring and radiation dose monitoring.
        5.1.2.    Refer to the laboratory chemical hygiene plan (or equivalent) for general
                 safety rules regarding chemicals in the workplace.
   5.2. Radiological
        5.2.1.    Hot particles (DRPs)
                 5.2.1.1.  Hot particles, also termed "discrete radioactive particles" (DRPs),
                          will be small, on the order of 1 mm or less. Typically, DRPs are not
                          evenly distributed in the media and their radiation emissions are not
                          uniform in all directions (anisotropic). Filtration using a 0.45-um or
                          finer filter will minimize the presence of these particles.
                 5.2.1.2.  Care should be taken to provide suitable containment for filter media
                          used in the pretreatment of samples that may have DRPs, because
                          the particles become highly statically charged as they dry out and
                          will "jump" to other surfaces causing contamination.
                 5.2.1.3.  Filter media should be individually surveyed for the presence of
                          these particles, and this information reported with the final  sample
                          results.
        5.2.2.    For samples with detectable activity concentrations of these radionuclides,
                 labware should be used only once due to potential for cross contamination.
   5.3. Procedure-Specific Non-Radiological Hazards:
        5.3.1.    Particular attention should be paid to the discussion of hydrofluoric acid  (HF).
                 HF is an extremely dangerous chemical used in the preparation of some of the
                 reagents and in the microprecipitation procedure. Appropriate personal
                 protective equipment (PPE) must be obtained and used in strict accordance
                 with the laboratory safety program specification.

6.  Equipment and Supplies
   6.1. Analytical balance with 0.01-g readability or better.
   6.2. Cartridge reservoirs, 10- or 20-mL syringe style with locking device, or equivalent.
   6.3. Centrifuge able to accommodate 250-mL flasks.
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     Isotopic Uranium (238U, 235U, and 234U) in Water: Rapid Method for High-Activity Samples
   6.4.  Centrifuge flasks with 250-mL capacity.
   6.5.  Filter with 0.45-um membrane.
   6.6.  Filter apparatus with a 25-mm diameter, polysulfone, filtration chimney, stem support,
         and stainless steel support. A single-use (disposable) filter funnel/filter combination
         may be used, to avoid cross contamination.
   6.7.  25-mm polypropylene filter with 0.1-um pore size.
   6.8.  Stainless steel planchets or other sample mounts that are able to hold the 25-mm filter.
   6.9.  Tweezers.
   6.10. 100-uL pipette, or equivalent, and appropriate plastic tips.
   6.11. 10-mL plastic culture tubes with caps.
   6.12. Vacuum pump or laboratory vacuum system.
   6.13. Tips, white inner, Eichrom part number AC-1000-IT, or equivalent.
   6.14. Tips, yellow outer, Eichrom part number AC-1000-OT, or equivalent.
   6.15. Vacuum Box, such as Eichrom part number AC-24-BOX, or equivalent.
   6.16. Vortex mixer.
   6.17. Miscellaneous labware, plastic or glass, both 250 and 350 mL.

7.  Reagents and Standards

   Note: All reagents are American Chemical Society (ACS) reagent grade or equivalent unless otherwise
   specified.

   Note: Unless otherwise indicated, all references to water should be understood to mean Type I Reagent
   water. All solutions used in microprecipitation should be prepared with water filtered through a 0.45-um
   (or better) filter.

   7.1.  Ammonium hydrogen oxalate (0.1M): Dissolve 6.3 g of oxalic acid (H2C2O4-2H2O)
         and 7.1 g of ammonium oxalate ((NH4)2C2O4'H2O) in 900 mL of water, and dilute to 1
         L with water.
   7.2.  Ammonium hydrogen phosphate (3.2 M): Dissolve 106 g of (ML^HPC^ in 200 mL of
         water. Heat gently to dissolve and dilute to 250 mL with water.
   7.3.  Ammonium hydroxide (15 M): Concentrated NFLjOH,  available commercially.
   7.4.  Ammonium thiocyanate indicator (1 M): Dissolve 7.6 g of ammonium thiocyanate
         (NFLtSCN) in 90  mL of water and dilute to 100 mL with water. An appropriate quantity
         of sodium thiocyanate (8.1 g) or potassium thiocyanate (9.7  g) may be substituted for
         ammonium thiocyanate.
   7.5.  Ascorbic acid (1 M): Dissolve 17.6 g of ascorbic acid (CeHgOe) in 90 mL of water and
         dilute to 100 mL  with water. Prepare weekly.
   7.6.  Calcium nitrate (0.9 M): Dissolve 53 g of calcium nitrate tetrahydrate (Ca(NO3)2'4H2O)
         in 100 mL of water and dilute to 250 mL with water.
   7.7.  Ethanol, 100 %: Anhydrous  C2HsOH, available commercially.
         7.7.1.   Ethanol, (-80% v/v): Mix 80 mL 100% ethanol and 20 mL water.
   7.8.  Ferrous sulfamate (0.6 M): Add 57 g of sulfamic acid ( NF^SOsH) to 150 mL of water
         and heat to 70 °C. Slowly add 7 g of iron powder (< 100 mesh size) while heating and
         stirring (magnetic stirrer should be used) until dissolved (may take as long as two
         hours). Filter the  hot solution (using a qualitative filter), transfer to flask, and dilute to
         200 mL with water. Prepare  fresh weekly.
   7.9.  Hydrochloric acid (12 M): Concentrated HC1, available commercially.
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     Isotopic Uranium (238U, 235U, and 234U) in Water: Rapid Method for High-Activity Samples
        7.9.1.    Hydrochloric acid (9 M): Add 750 mL of concentrated HC1 to 100 mL of
                 water and dilute to 1 L with water.
        7.9.2.    Hydrochloric acid (4 M): Add 333 mL of concentrated HC1 to 500 mL of
                 water and dilute to 1 L with water.
        7.9.3.    Hydrochloric acid (1 M): Add 83 mL of concentrated HC1 to 500 mL of water
                 and dilute to 1 L with water.
   7.10. Hydrofluoric acid (28 M): Concentrated HF, available commercially.
        7.10.1.   Hydrofluoric acid (0.58 M): Add 20 mL of concentrated HF to 980 mL of
                 filtered demineralized water and mix. Store in a plastic bottle.
   7.11. Neodymium standard solution (1000 ug/mL): May be purchased from a supplier of
        standards for atomic spectroscopy.
   7.12. Neodymium carrier solution (0.50 mg/mL): Dilute 10 mL of the neodymium standard
        solution (7.11) to 20.0 mL with  filtered demineralized water. This solution is stable for
        up to six months.
   7.13. Neodymium fluoride substrate solution (10 jig/mL): Pipette 5.0 mL of neodymium
        standard solution (7.11) into a 500-mL plastic bottle. Add 460 mL of  1-M HC1 to the
        plastic bottle. Cap the bottle  and shake to mix. Measure 40 mL of concentrated HF in a
        plastic graduated cylinder and add to the bottle. Recap the bottle and shake to mix
        thoroughly.  This solution is stable for up to six months.
   7.14. Nitric acid (16M): Concentrated HNO3, available commercially.
        7.14.1.   Nitric acid (3 M): Add 191 mL of concentrated HNO3 to 700 mL of water and
                 dilute to 1 L with water.
        7.14.2.   Nitric acid (2 M): Add 127 mL of concentrated HNO3 to 800 mL of water and
                 dilute to 1 L with water.
        7.14.3.   Nitric acid (0.5 M): Add 32 mL of concentrated HNO3 to 900 mL of water
                 and dilute to 1 L with water.
   7.15. Nitric acid (3 M) - aluminum nitrate (1.0 M) solution: Dissolve 210 g of anhydrous
        aluminum nitrate (A1(NO3)3) in  700 mL of water. Add 190 mL of concentrated HNO3
        (7.14) and dilute to 1 L with water. An appropriate quantity of aluminum nitrate
        nonahydrate (375 g)  may be  substituted for anhydrous aluminum nitrate.
   7.16. Phenolphthalein solution: Dissolve 1 g phenolphthalein in 100 mL 95% isopropyl
        alcohol and  dilute with 100 mL  of water.
   7.17. Titanium chloride: 20 %  solution, stored in an air-tight  container and  away from light.
   7.18. Uranium-232 tracer solution: 6-10  dpm of 232U per aliquant, activity added known to at
        least 5 % (combined standard uncertainty of no more than 5 %).
   7.19. UTEVA Resin: 2-mL cartridge, 50-100 ng, Eichrom part number UT-R50-S and UT-
        R200-S, or equivalent.

8.  Sample Collection, Preservation, and  Storage
   8.1.  No sample preservation is required if sample is delivered to the laboratory within 3
        days of sampling date/time.
   8.2.  If the dissolved concentration of uranium is sought, the insoluble fraction must be
        removed by filtration before  preserving with acid.
   8.3.  If the sample is to be held for more than three days, nitric acid shall be added until
        pH<2.
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     Isotopic Uranium (238U, 235U, and 234U) in Water: Rapid Method for High-Activity Samples
9.  Quality Control
   9.1.  Batch quality control results shall be evaluated and meet applicable Analytical Project
        Specifications (APS) prior to release of unqualified data. In the absence of project-
        defined APS or a project-specific quality assurance project plan (QAPP), the quality
        control  sample acceptance criteria defined in the laboratory quality manual and
        procedures shall be used to determine acceptable performance for this method.
        9.1.1.    A laboratory control sample (LCS) shall be run with each batch of samples.
                 The concentration of the LCS should be at or near the action level or level of
                 interest for the project.
        9.1.2.    One method blank shall be run with each batch of samples. The laboratory
                 blank should consist of laboratory water.
        9.1.3.    One laboratory duplicate shall be run with each batch of samples. The
                 laboratory duplicate is prepared by removing an aliquant from the original
                 sample container.
        9.1.4.    A matrix spike sample may be included as a batch quality control sample if
                 there is concern that matrix interferences, may compromise chemical yield
                 measurements, or overall data quality.
   9.2.  The source preparation method should produce a sample test source that produces a
        spectrum with the full width at half maximum (FWHM) of 50-100 keV for each peak
        in the spectrum (with the exception of 235U). Precipitate reprocessing should be
        considered if this range of FWHM cannot be achieved.
   9.3.  This method is capable of achieving a MMR of 2.6 pCi/L at or below an action level of
        20 pCi/L. This may be adjusted if the event-specific MQOs are different.
   9.4.  This method is capable of achieving a ^MR of 13 % above 20 pCi/L.  This may be
        adjusted if the event-specific MQOs are different.
   9.5. This method is  capable of achieving a required minimum detectable concentration
       (MDC)of 1.5pCi/L.

10. Calibration and Standardization
   10.1. Set up the alpha spectrometry system according to the manufacturer's
        recommendations. The energy  range of the spectrometry system should  at least include
        the region between 3-8 MeV.
   10.2. Calibrate each detector used to count samples according to ASTM Standard Practice
        D7282, Section 18, "Alpha Spectrometry Instrument Calibrations" (see reference  16.3).
   10.3. Continuing Instrument Quality Control Testing shall be performed according to ASTM
        Standard Practice D7282, Sections 20, 21, and 24.

11. Procedure
   11.1. Water Sample Preparation
        11.1.1.   As required, filter the 100-200 mL sample aliquant through a 0.45-um filter
                 and collect the sample in an appropriate size beaker.
        11.1.2.   Acidify the sample with concentrated HNOs. This usually requires adding
                 about 2 mL of concentrated HNOs per 1000 mL of sample.  However, samples
                 that are initially alkaline, or that may have high carbonate content, may require
                 substantially more acid. It is important that the pH be verified to be below 2.0,
                 ensuring that all carbonate (a uranium complexing agent) has been removed.
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     Isotopic Uranium (238U, 235U, and 234U) in Water: Rapid Method for High-Activity Samples
         11.1.3.  Following the laboratory protocol, add 6-10 dpm of 232U as a tracer.

                 Note: For a sample approximately 100 mL or less, the evaporation option is recommended.
                 Proceed to Step 11.1.5. Otherwise continue to Step 11.1.4.

         11.1.4.  Calcium phosphate coprecipitation option
                 11.1.4.1.   Add 0.5 mL of 0.9 M Ca(NO3)2 to each beaker. Place each beaker
                            on a hot plate, cover with a watch glass, and heat until boiling.
                 11.1.4.2.   Once the sample boils, take the watch glass off the beaker and
                            lower the heat.
                 11.1.4.3.   Add 2-3 drops of phenolphthalein indicator and 200 |iL of 3.2 M
                            (NH4)2HPO4 solution.
                 11.1.4.4.   Add enough concentrated NH4OH with a squeeze bottle to reach
                            the phenolphthalein end point (a persistent pink color) and form
                            Ca3(PO4)2 precipitate. NH4OH should be added very slowly. Stir
                            the solution with a glass rod. Allow the sample to heat gently to
                            digest the precipitate for another 20-30 minutes.

                            Note: The calcium phosphate precipitation should be completed promptly
                            following pH adjustment to the phenolphthalein endpoint to minimize
                            absorption of CO2 and formation of a soluble carbonate complex with U
                            that will lead to incomplete precipitation of U.

                 11.1.4.5.   If the sample volume is too large to centrifuge the entire sample,
                            allow precipitate to settle until solution can be decanted (30
                            minutes to 2 hours) and go to Step  11.1.4.7.
                 11.1.4.6.   If the volume is small enough to centrifuge go to Step 11.1.4.8.
                 11.1.4.7.   Decant supernatant solution and discard to waste.
                 11.1.4.8.   Transfer the precipitate to a 250-mL centrifuge tube, completing
                            the transfer with a few milliliters of water, and centrifuge the
                            precipitate for approximately 10 minutes at 2000 rpm.
                 11.1.4.9.   Decant supernatant solution and discard to waste.
                 11.1.4.10. Wash the precipitate with an amount of water approximately twice
                            the volume of the precipitate. Mix well using a stirring rod,
                            breaking up the precipitate if necessary. Centrifuge for 5-10
                            minutes at 2000 rpm. Discard the supernatant solution.
                 11.1.4.11. Dissolve precipitate in approximately 5 mL concentrated HNOs.
                            Transfer solution to a 100 mL beaker. Rinse centrifuge tube with
                            2-3 mL of concentrated HNOs and transfer to the same beaker.
                            Evaporate solution to dryness and go to Step 11.2.
         11.1.5.  Evaporation option to reduce volume and to digest organic components
                 11.1.5.1.   Evaporate sample to less than 50 mL and transfer to a 100 mL
                            beaker.

                            Note: For some water samples, CaSO4 formation may occur during
                            evaporation. If this occurs, use the calcium phosphate precipitation option
                            in Step 11.1.4.
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     Isotopic Uranium (238U, 235U, and 234U) in Water: Rapid Method for High-Activity Samples
                  11.1.5.2.   Gently evaporate the sample to dryness and redissolve in
                             approximately 5 mL of concentrated HNOs.
                  11.1.5.3.   Repeat Step 11.1.5.2 two more times, evaporate to dryness, and go
                             to Step 11.2.
    11.2. Actinide Separations using Eichrom Resins
         11.2.1.   Redissolve Ca3(PO4)2 residue or evaporated water sample
                  11.2.1.1.   Dissolve either residue with 10 mL of 3 M HNO3 - 1.0 M
                             A1(N03)3.

                             Note: An additional 5 mL may be necessary if the residue volume is large.

                  11.2.1.2.   Add 2 mL of 0.6 M ferrous sulfamate to each solution.  Swirl to
                             mix.

                             Note: If the additional 5 mL was used to dissolve the sample in Step
                             11.2.1.1, add a total of 3 mL of ferrous sulfamate solution.

                  11.2.1.3.   Add 1 drop of 1  M ammonium thiocyanate indicator to each
                             sample and mix.

                             Note: The color of the solution turns deep red, due to the formation of
                             soluble ferric thiocyanate complex.

                  11.2.1.4.   Add 1 mL of 1 M ascorbic acid to each solution, swirling to mix.
                             Wait for 2-3 minutes.

                             Note: The red color should disappear which indicates reduction of Fe+3 to
                             Fe+2. If the red color persists, then additional ascorbic acid solution is added
                             drop-wise with mixing until the red color disappears.

                             Note: If particles are observed suspended in the solution, centrifuge the
                             sample at 2000 rpm. The supernatant solution will be transferred to the
                             column in Step 11.2.3.1. The precipitates will be discarded.

         11.2.2.   Set up the vacuum box with UTEVA cartridges as follows:

                  Note: Steps 11.2.2.1 to 11.2.2.5 deal with a commercially available filtration system.
                  Other vacuum systems developed by individual laboratories may be substituted here as
                  long as the laboratory has provided guidance to analysts in their use.

                  11.2.2.1.   Place the inner tube rack (supplied with vacuum box) into the
                             vacuum box with the centrifuge tubes  in the rack. Fit the lid to the
                             vacuum system box.
                  11.2.2.2.   Place the yellow outer tips into all 24 openings of the lid of the
                             vacuum box. Fit in the inner white tip  into each yellow tip.
                  11.2.2.3.   For each sample solution, fit in the UTEVA cartridge on to the
                             inner white tip.
                  11.2.2.4.   Lock syringe barrels (funnels/reservoirs) to the top end of the
                             UTEVA cartridge.
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     Isotopic Uranium (238U, 235U, and 234U) in Water: Rapid Method for High-Activity Samples
                  11.2.2.5.  Connect the vacuum pump to the box. Turn the vacuum pump on
                            and ensure proper fitting of the lid.

                            IMPORTANT: The unused openings on the vacuum box should be sealed.
                            Yellow caps (included with the vacuum box) can be used to plug unused
                            white tips to achieve good seal during the separation.

                  11.2.2.6.  Add 5 mL of 3-M HNO3 to the funnel to precondition the UTEVA
                            cartridge.
                  11.2.2.7'.  Adjust the vacuum pressure to achieve a flow-rate of ~1 mL/min.

                            IMPORTANT: Unless otherwise specified in the procedure, use a flow rate
                            of ~ 1 mL/min for load and strip solutions and ~ 3 mL/min for rinse
                            solutions.

         11.23.   U separation from Pu, Am using UTEVA resin
                  11.2.3.1.  Transfer each solution from Step 11.2.1.4 into the appropriate
                            funnel by pouring or by using a plastic transfer pipette.  Allow
                            solution to pass through both the cartridges at a flow rate of ~1
                            mL/min.
                  11.2.3.2.  Add 5 mL of 3-M HNOs to each beaker as a rinse and transfer each
                            solution into the appropriate  funnel (the flow rate can be adjusted
                            to ~3 mL/min).
                  11.2.3.3.  Add 5 mL of 3-M HNOs into each funnel as second column rinse
                            (flow rate ~3 mL/min).

                            Note: Maintain the flow rate at <3 mL/min in the next several steps.

                            Note: If a high concentration of 210Po is present  in the sample an additional
                            3 M HNO3 rinse is necessary to eliminate 210Po. Add 30 mL of 3 M HNO3
                            rinse to each UTEVA cartridge in increments of 10 mL. Continue with Step
                            11.2.3.4.

                  11.2.3.4.  Pipette 5 mL of 9-M HC1 into each UTEVA cartridge and allow it
                            to drain. Discard this  rinse.

                            Note: This rinse converts the resin to the chloride system. Some Np may be
                            removed here.

                  11.2.3.5.  Pipette 20 mL of 5-M HC1 - 0.05 M oxalic acid into each UTEVA
                            cartridge and allow it to drain. Discard this rinse.

                            Note: This rinse removes neptunium and thorium from the cartridge. The
                            9-M HC1 and 5-M HC1 - 0.05 M oxalic acid rinses also remove any residual
                            ferrous ion that might interfere with micoprecipitation.

                  11.2.3.6.  Ensure that clean, labeled tubes are placed in the tube rack.
                  11.2.3.7.  Pipette  15 mL of 1-M HC1 into each cartridge to strip the uranium.
                            Allow to drain.
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     Isotopic Uranium (238U, 235U, and 234U) in Water: Rapid Method for High-Activity Samples
                  11.2.3.8.   Transfer the eluate containing uranium to a 50-mL beaker. Rinse
                            the tube with a few milliliters of water and add to the same beaker.
                  11.2.3.9.   Evaporate samples to near soft dryness. If a slight white residue
                            appears, wet-ash by adding a few mL of HNO3, heating till near
                            dryness and repeating the process 2-3 times. Once wet-ashing is
                            complete, convert the sample to the chloride form by treating it 2-
                            3 times with 1-2-mL portions of HC1 and evaporating to near
                            dryness.

                            Note: Do not bake the residue.

                  11.2.3.10.  Allow the beaker to cool slightly and then add a few drops of
                            concentrated HC1 followed by 1 mL of water.
                  11.2.3.11.  Transfer the solution to a 10-mL plastic culture tube.  Rinse the
                            original sample vessel twice with 1-mL washes of 1-M HC1,
                            transferring the rinses to a culture tube. Mix by gently swirling the
                            solution in the tube.
                  11.2.3.12.  Proceed to neodymium fluoride microprecipitation, Step 11.3.
                  11.2.3.13.  Discard the UTEVA cartridge.
    11.3. Preparation of the Sample Test Source

         Note: Instructions below describe preparation of a single Sample Test Source. Several STSs can be
         prepared simultaneously if a multi-channel vacuum box (whale apparatus) is available.

         11.3.1.   Add 100 jiL of the neodymium carrier solution to the culture tube with a
                 micropipette. Gently swirl the tube to mix the solution.
         11.3.2.   Add four drops of 20% TiCb solution to the tube and mix gently. A strong
                 permanent violet color should appear. If the color fails to appear, add a few
                 more drops of the TiCb solution to provide the permanent violet color.
         11.3.3.   Add 1 mL of concentrated HF to the tube and mix well by gently swirling.
         11.3.4.   Cap the tube and place it a cold-water ice bath for at least 30 minutes.
         11.3.5.   Insert the polysulfone filter stem in the 250-mL vacuum flask. Place the
                 stainless steel  screen on top of the fitted plastic filter stem.
         11.3.6.   Place a 25-mm polymeric filter face up on the stainless steel screen. Center
                 the filter on the stainless steel screen support and apply vacuum.  Wet the filter
                 with 100 % ethanol, followed by filtered Type I water.

                  Caution: There is no visible difference between the two sides of the filter. If the filter is
                  turned over accidentally, it is recommended that the filter be discarded and a fresh one
                  removed from the container.

         11.3.7.   Lock the filter chimney firmly in place on the filter screen and wash the filter
                 with additional filtered Type I water wash.
         11.3.8.   Pour 5.0 mL of neodymium substrate solution down the side of the filter
                 chimney, avoiding directing the stream at the filter. When the solution passes
                 through the filter, wait at least 15 seconds before the next step.
         11.3.9.   Repeat Step 11.3.8 with an additional 5.0 mL of the substrate solution.
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     Isotopic Uranium (238U, 235U, and 234U) in Water: Rapid Method for High-Activity Samples
         11.3.10. Pour the sample from Step 11.3.4 down the side of the filter chimney and
                 allow the vacuum to draw the solution through.
         11.3.11. Rinse the tube twice with 2 mL of 0.58-M HF, stirring each wash briefly using
                 a vortex mixer and pouring each wash down the  side of the filter chimney.
         11.3.12. Repeat rinse using 2-mL filtered Type I water once.
         11.3.13. Repeat rinse using 2-mL 80% ethyl alcohol once.
         11.3.14. Wash any drops remaining on the sides of the chimney down toward the filter
                 with a few mL 80% ethyl  alcohol.

                 Caution: Directing a stream of liquid onto the filter will disturb the distribution of the
                 precipitate on the filter and render the sample unsuitable for a-spectrometry resolution.

         11.3.15. Without turning off the vacuum, remove the filter chimney.
         11.3.16. Turn off the vacuum to remove the filter. Discard the filtrate to waste for
                 future disposal. If the filtrate is to be retained, it should be placed in a plastic
                 container to avoid dissolution of the glass vessel by dilute HF.
         11.3.17. Place the filter on a properly labeled mounting disc, secure with  a mounting
                 ring or other device that will render the filter flat for counting.
         11.3.18. Let the sample air dry for a few minutes and when dry, place in a container
                 suitable for transfer and submit for counting.
         11.3.19. Count the sample on an alpha spectrometer.

                 Note: Other methods for STS preparation, such  as electroplating or microprecipitation
                 with cerium fluoride, may be used in lieu of the neodymium fluoride microprecipitation,
                 but any such substitution must be validated as described in Section 1.4.

12. Data Analysis and Calculations
   12.1. Equations for determination of final result, combined standard uncertainty and
        radiochemical yield (if required).

        The activity concentration of an analyte and its combined standard uncertainty are
        calculated using the following equations:

                  AtxRaxDtxIt
                  FaxtftxZ)ax/a
          and
          where:
            ACn   =    activity concentration of the analyte at time of count, (pCi/L)
            At     =    activity of the tracer added to the sample aliquant at its reference date
                        and time, (pCi)
            Ra     =    net count rate of the analyte in the defined region of interest (ROI), in
                        counts per second
            Rt     =    net count rate of the tracer in the defined ROI, in counts per second
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     Isotopic Uranium (238U, 235U, and 234U) in Water: Rapid Method for High-Activity Samples
             Fa     =    volume of the sample aliquant, (L)
             DI     =    correction factor for decay of the tracer from its reference date and
                         time to the midpoint of the counting period
             Z)a     =    correction factor for decay of the analyte from the time of sample
                         collection (or other reference time) to the midpoint of the counting
                         period (if required)
             /t      =    probability of a emission in the defined ROI, per decay of the tracer
                         (Table 17.1)
             /a      =    probability of a emission in the defined ROI, per decay of the analyte
                         (Table 17.1)
             uc(ACa)     =   combined standard uncertainty of the activity concentration of the
                         analyte (pCi/L)
             u(Ai)   =    standard uncertainty of the activity of the tracer added to the sample
                         (pCi)
             w(Fa)   =    standard uncertainty of the volume of sample aliquant (L)
             u(Ra)   =    standard uncertainty of the net count rate of the analyte, in counts per
                         second
             u(Ri)   =    standard uncertainty of the net count rate of the tracer, in counts per
                         second

           Note: The uncertainties of the decay-correction factors and of the probability of decay
           factors are assumed to be negligible.

           Note: The equation for the combined standard uncertainty (uc(AC^)) calculation is arranged to
           eliminate the possibility of dividing by zero if Ra = 0.

           Note: The standard uncertainty of the activity of the tracer added to the sample must reflect that
           associated with the activity of the standard reference material and any other significant sources
           of uncertainty such as those introduced during the preparation of the tracer solution (e.g.,
           weighing or dilution factors) and during the process of adding the tracer to the sample.

           12.1.1.   The net count rate of an analyte or tracer and the associated standard
                    uncertainties are calculated using the following equations:

                    and
                            V   <
                    where:
              u(Rx)   =    standard uncertainty of the net count rate of tracer or analyte, in
                           counts per second1
1 For methods with very low counts, MARLAP Section 19.5.2.2 recommends adding one count each to the gross
counts and the background counts when estimating the uncertainty of the respective net counts. This minimizes


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     Isotopic Uranium (238U, 235U, and 234U) in Water: Rapid Method for High-Activity Samples
              Rx     =    net count rate of analyte or tracer, in counts per second
              Cx     =    sample counts in the analyte or the tracer peak
              4      =    sample count time (s)
              Cbx     =    background counts in the same region of interest (ROI) as for x
              tb      =    background count time (s)
           The radiochemical yield and the combined standard uncertainty can be estimated for
           each sample, when required, using the following equations:
           where:
              RY     =    radiochemical yield of the tracer, expressed as a fraction
              Rt      =    net count rate of the tracer, in counts per second
              At      =    activity of the tracer added to the sample (pCi)
              Dt      =    correction factor for decay of the tracer from its reference date and
                           time to the midpoint of the counting period
              /t      =    probability of a emission in the defined ROI per decay of the tracer
                           (Table 17.1)
              e       =    detector efficiency, expressed as a fraction
              uc(RY) =    combined standard uncertainty of the radiochemical yield
              u(Rt)   =    standard uncertainty of the net count rate of the tracer, in counts per
                           second
              u(At)   =    standard uncertainty of the activity of the tracer added to the sample
                           (pCi)
              u(e)    =    standard uncertainly of the detector efficiency

           12.1.2.   If the critical level concentration (Sc) or the minimum detectable
                    concentration (MDC) are requested (at an error rate of 5%), they can be
                    calculated using the following equations:2
negative bias in the estimate of uncertainty and protects against calculating zero uncertainty when zero total counts
are observed for the sample and background.
2 The formulations for the critical level and minimum detectable concentration are based on the Stapleton
Approximation as recommended in MARLAP Section 20A.2.2, Equations 20.54 and 20A.3.2, and Equation 20.74,
respectively. The formulations presented here assume an error rate of a = 0.05, ft = 0.05 (with z\-a = z^ = 1.645),
and d = 0.4. For methods with very low numbers of counts, these expressions provide better estimates than do the
traditional formulas for the critical level and MDC.


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     Isotopic Uranium (238U, 235U, and 234U) in Water: Rapid Method for High-Activity Samples
     S =
           0.4xp--l +0.677x 1 + ^-  +1.645 x \(Rhath + 0.4)x-^-x  1 + ^-
                \ f              \    f  I         -ivoao        //
                V'fe    J         V   lb J         \              lb   V   lb ;
                                             x At x Dt x It
                                        tsxVaxRtxDax!a
     MDC =

     where:
                                                          x Dt  x It
tsxVaxRtxDax!a
              =  background count rate for the analyte in the defined ROI, in counts per second
     12.2. Results Reporting
          12.2.1. The following data should be reported for each result: volume of sample used,
                 yield of tracer and its uncertainty, and FWHM of each peak used in the
                 analysis.
          12.2.2. The following conventions should be noted for each result:
                 12.2.2.1. Result in scientific notation ± combined standard uncertainty.
                 12.2.2.2. If solid material was filtered from the solution and analyzed
                         separately, the results of that analysis should be reported separately
                         as pCi/L of the original volume from which the solids were filtered if
                         no other guidance is provided on reporting of results for the solids.
                         For example:
                                 238U for Sample 12-1-99:
                                    Filtrate Result:           12.8 ± 1.5 pCi/L
                                    Filtered Residue Result:    2.5 ± 0.3 pCi/L

13.  Method Performance
     13.1. Method validation results are to be reported.
     13.2. Expected turnaround time per batch of 14 samples plus QC, assuming
          microprecipitations for the whole batch are performed simultaneously using a vacuum
          box system:
          13.2.1. For an analysis of a 200 mL sample  aliquant, sample preparation and
                 digestion should take -3.5 h.
          13.2.2. Purification and  separation of the uranium fraction using cartridges and
                 vacuum box system should take -1.5 h.
          13.2.3. The sample test source preparation takes -1 h (longer if wet-ashing is
                 necessary).
          13.2.4. A 1-h counting time should be sufficient to meet the MQOs listed in 9.3 and
                 9.4, assuming detector efficiency of 0.2-0.3, and radiochemical yield of at
                 least 0.5. A different counting time may be necessary to meet these MQOs if
                 any of the relevant parameters are significantly different.
          13.2.5. Data should be ready for reduction -6 h after beginning of analysis.
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     Isotopic Uranium (238U, 235U, and 234U) in Water: Rapid Method for High-Activity Samples
14.   Pollution Prevention: This method utilizes small volume (2 mL) extraction
     chromatographic resin columns. This approach leads to a significant reduction in the
     volumes of load, rinse and strip solutions, as compared to classical methods using ion
     exchange resins to separate and purify uranium.

15.   Waste Management
     15.1. Types of waste generated per sample analyzed
          15.1.1. If calcium phosphate coprecipitation is performed, 100-1000 mL of decanted
                 solution that is pH neutral is generated.
          15.1.2. Approximately 65 mL of acidic waste from loading and rinsing the extraction
                 column will be generated. The solution may contain unknown quantities of
                 radionuclides as may be present in the original sample. If presence of other
                 radionuclides in the sample is suspected, combined effluents should be
                 collected separately from other rinses to minimize quantity of mixed waste
                 generated.
          15.1.3. Approximately 45 mL of slightly acidic waste, containing 1 mL of HF  and ~ 8
                 mL ethanol are produced in the microprecipitation step.
          15.1.4. UTEVA cartridge - ready for appropriate disposal.
     15.2. Evaluate all waste streams to ensure that all local, state, and federal disposal
          requirements are met.

16.   References
     16.1. ACW02, Rev.  1.3, "Uranium in Water," Eichrom Technologies, Inc., Lisle, Illinois
          (April 2001).
     16.2. G-03, V.I  "Microprecipitation Source Preparation for Alpha Spectrometry," HASL-
          300, 28th Edition, (February 1997).
     16.3. ASTM D7282 "Standard Practice for Set-up, Calibration, and Quality Control  of
          Instruments Used for Radioactivity Measurements," ASTM Book of Standards 11.02,
          current version, ASTM International, West Conshohocken, PA.
     16.4. VBS01, "Setup and Operation Instructions for Eichrom's Vacuum Box System
          (VBS)," Eichrom Technologies, Inc., Lisle, Illinois (Rev. 1.3, January 30, 2004).
     16.5. U.S. Environmental Protection Agency (EPA). 2009. Method Validation Guide for
          Radiological Laboratories Participating in Incident Response Activities. Revision 0.
          Office of Air and Radiation, Washington, DC. EPA 402-R-09-006, June. Available
          at: www.epa.gov/narel/incident_guides.html.
     16.6. Multi-Agency Radiological Laboratory Analytical Protocols Manual (MARLAP).
          2004. EPA 402-B-1304 04-001A, July. Volume I, Chapters 6, 7, 20, Glossary;
          Volume II and Volume III, Appendix G. Available at: www.epa.gov/radiation/
          marlap/index.html.
     16.7. ASTM Dl 193, "Standard Specification for Reagent Water" ASTM Book of
          Standards  11.01, current version, ASTM International, West Conshohocken, PA.
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     Isotopic Uranium (238U, 235U, and 234U) in Water: Rapid Method for High-Activity Samples
17. Tables, Diagrams, Flow Charts, and Validation Data




   17.1. Nuclide Decay and Radiation Data




                          Table 17.1 - Decay and Radiation Data
Nuclide
238U
235U
234U
232U
Half-Life
(Years)
4.468xl09
7.038xl08
2.457xl05
68.9
>,
(s-1)
4.916xlO~18
3.121xlO~17
8.940xlO~14
3.19xlO~10
Abundance
0.79
0.21
0.050
0.042
0.0170
0.0070
0.0210
0.55
0.170
0.7138
0.2842
0.002
0.6815
0.3155
a Energy
(MeV)
4.198
4.151
4.596
4.556
4.502
4.435
4.414
4.398
4.366
4.775
4.722
4.604
5.320
5.263
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     Isotopic Uranium (238U, 235U, and 234U) in Water: Rapid Method for High-Activity Samples
17.2.  Ingrowth Curves and Ingrowth Factors

       This section intentionally left blank


17.3.  Spectrum from a Processed Sample
160-
150-
•
130-
120-
•
100-
90-
70-
60-
.

40-
30-
10-
0 •

















IJ




U-238
|
||
i



'
,


i -
i










lu-2!
J













5
J













l'
k









h
e

\f
{
\\
I •
_,\
'in
I







1-2;
\













4










/!
1
J
II
U-23
y














2

          3049  3349  3649  3949  4249  4549  4849  5149  5449  5749  6049  6349  6649  6949  7249  7549  7649
                                            Energy (keV)
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     Isotopic Uranium (238U, 235U, and 234U) in Water: Rapid Method for High-Activity Samples
17.4.   Decay Scheme: Ingrowth is not generally a large concern with this analysis unless one is
       running sequential analysis for uranium and plutonium with 236Pu tracer (due to ingrowth
       of 232U tracer) or sequential analyses for uranium and thorium (due to 228Th tracer
       ingrowth in the 232U tracer).
P
3.3x1 04 y
231 pa


1.1 d
P


235U
a
7.04x1 0B y
231 Th







23^
a
2.45x105y



a
230Th




li 1
u
6

7h
P
234pa



2381 1

4.47x103
P
24 d
234Th
i n

a
y
-
                                        7.5x104y
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      Isotopic Uranium (238U, 235U, and 234U) in Water: Rapid Method for High-Activity Samples
   17.5.  Flowchart
                        Separation Scheme and Timeline for Determination of
                                      U Isotopes in Water Samples
         Sample preparation (Step 11.1)
         1.  Digestion (Step 11.1.5)
                      or
         2.  Calcium phosphate coprecipitation
             (Step 11.1.4)
         3.  Add phenolphthalein (Step 11.1.4.3)
         (1-2 hours)
                        T
         Preparation of load solution (Step
            11.2.1)
         1. Dissolve phosphate.
         2. Add sulfamate, thiocyanate and
            ascorbic acid
         (5 min)
                         T
   Set-up of UTEVA cartridge
   using vacuum box (Step 11.2.2)
   1.  Assembly
   2.  Precondition with 5 ml 3 M HN03
   la) ~3 mL/min
                             Load sample: @ ~1 mL/min
                             Rinse: 5 mL3M HN03, @ ~3 mL/min
                             2nd rinse: 5 ml_3M HN03,@~3 mL/min
                             Additional 30 mL 3M HMO,, rinse for Po-210 if present
                             (Step 11.2.3)
                             (~ 25 min)
Discard effluents


I
J
                              Rinse: 5 mLof9 M HCI
                              20 mL of 5 M HCI - 0.05 M oxalic acid
                              (Step 11.2.3.4-11.2.3.5)
Discard
effluents


I

i
                                Elute U with 15 mL of 1 M HCI collecting eluent
                                (Step 11.2.3.7)
Discard UTEVA
Column
« I
* J
                              Transfer eluent to beaker and evaporate
                              Add drops of HCL and 1 mL H20 to dissolve
                              Transfer to culture tube w/2 1-mL rinses of 1M HCI.
                              (Step 11.2.3.8-11.2.3.11)
                              (15 min)
                                    Microprecipitation
                                    1. Add NdF3 carrier and wait 30 min
                                    2. Filter, dry, mount
                                    (Step 11.3)
                                    (1 hour 15 min)
       Discard filtrates and washes
                                      Count sample test source (STS)
                                           for at least one hour
                                            (Step 11.3.19)
                                               (1 hour)
                                            Elapsed Time
                                           1 -2 hours
                                                                                       1-1 V4 hours
                                           1 % hours
                                           11/4 hours
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     Isotopic Uranium (238U, 235U, and 234U) in Water: Rapid Method for High-Activity Samples
                                           Appendix
Table Al - Composition of Atlanta Drinking Water Used for this Study
Metals by ICP-AES
Silicon
Aluminum
Barium
Calcium
Iron
Magnesium
Potassium
Sodium
Inorganic Anions
Chloride
Sulfate
Nitrogen, Nitrate (as N)
Carbon Dioxide
Bicarbonate Alkalinity
Carbonate Alkalinity
Radionuclide
Uranium 234, 235, 238
Plutonium 238, 239/240
Americium 24 1
Strontium 90
***
Radium 226
Concentration (mg/L)*
3.18
<0.200
0.0133
9.38
<0.100
<0.500
<0.500
<0.500

12.7
15.6
1.19

23.8
<3.00
Concentration (pCi/L)**
<0.01,<0.01,<0.01
<0.02, <0.02
<0.02
<0.3
0.11 ±0.27
-0.30 ±0.45
           Note: Analyses conducted by independent laboratories.
           *   Values below the reporting level are presented as less than (<) values.
               No measurement uncertainty was reported with values greater than the "Reporting
               Level."
            **  Reported values represent the calculated minimum detectable concentration (MDC)
               for the radionuclide(s).
           *** Two samples analyzed.
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