I
\
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United States
Environmental Protection
Agency
Office of Radiation and Indoor Air
National Air and Radiation
Environmental Laboratory
EPA402-R-07-007
January 2008
www.epa.gov/narel
Radiological Laboratory Sample
Analysis Guide for Incidents
of National Significance -
Radionuclides in Water
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EPA 402-R-07-007
www.epa.gov
January 2008
Revision 0
Radiological Laboratory
Sample Analysis Guide for
Incidents of National Significance
Radionuclides in Water
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
Recycled/Recyclable
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Radiological Laboratory Sample Analysis Guide for Incidents of National Significance Radionuclides in Water
Preface
The document describes the likely analytical decision paths that would be required by personnel at
a radioanalytical laboratory following a radiological or nuclear incident, such as that caused by a
terrorist attack. EPA's responsibilities, as outlined in the National Response Plan Nuclear/
Radiological Incident Annex, include response and recovery actions to detect and identify radio-
active 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 (INS).
The need to ensure adequate laboratory infrastructure to support response and recovery actions
following an INS has been recognized by a number of federal agencies. The Integrated Consortium
of Laboratory Networks (ICLN), created through a memorandum of understanding in 2005 by ten
federal agencies, consists of existing and emerging laboratory networks across the Federal
Government. 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 and drinking water samples, EPA is
developing the Environmental Laboratory Response Network (eLRN). As an RFA for radiological
agents, eLRN will be responsible for monitoring, surveillance, and remediation, and will share
responsibility for incident response with the Department of Energy. As part of eLRN, EPA's Office
of Radiation and Indoor Air is leading an initiative to ensure that sufficient environmental
radioanalytical capability and competency exists across a core set of laboratories to carry out EPA's
designated RFA responsibilities.
Three radioanalytical scenarios, responding to two different public health questions, address the
immediate need to determine the concentration of known or unknown radionuclides in water. The
scenarios are based upon the radionuclides that probably would be released by a radiological
dispersion device or those that may be released intentionally into the drinking water supply. The first
analytical scenario assesses whether water samples pose immediate threats to human health and
warrant implementation of protective measures specific to radiation concerns. The second assesses
whether specific water sources (samples) are potable based on current national drinking water
standards. The third situation assumes that the radioactive contaminants are known, and a shortened
version of the first two analytical scenarios is used to help expedite the analysis process. Use of
established analytical schemes will increase the laboratory efficiency so that large numbers of
samples can be analyzed in a timely manner. The use of the analytical schemes and the associated
measurement quality objectives also will ensure that the radioanalytical data produced will be of
known quality appropriate for the intended incident response decisions.
As with any technical endeavor, actual radioanalytical projects may require particular methods or
techniques to meet specific measurement quality objectives. The document cannot address a
complete catalog of analytical methodologies or potential radionuclides. Radiochemical methods
to support response and recovery actions following a radiological or nuclear INS can be found in
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Radiological Laboratory Sample Analysis Guide for Incidents of National Significance Radionuclides in Water
Standardized Analytical Methods for Environmental Restoration following Homeland Security
Events, Revision 3 (EPA 600-R-07-015).
Detailed guidance on recommended radioanalytical practices may be found in current editions of
the Multi-Agency RadiologicalLaboratory AnalyticalProtocols Manual(MARLAP)andtheMwfe'-
Agency Radiation Survey and Site Investigation Manual (MARSSIM), both referenced in this
document. EPA is developing companion documents for air and soil samples. Familiarity with
Chapters 2 and 3 of MARLAP will be of significant benefit to the users of this guide.
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
This report was prepared for the National Air and Radiation Environmental Laboratory of the Office of Radiation
and Indoor Air, United States Environmental Protection Agency. It was prepared by Environmental Management
Support, Inc., of Silver Spring, Maryland, under contract 68-W-03-038, work assignments 21 and 35, managed
by David Carman. Mention of trade names or specific applications does not imply endorsement or acceptance
by EPA.
ii
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Radiological Laboratory Sample Analysis Guide for Incidents of National Significance Radionuclides in Water
Acknowledgments
This manual was developed by theNational Air and Radiation Environmental Laboratory (NAREL)
of EPA's Office of Radiation and Indoor Air (ORIA).
Dr. John Griggs served as 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 Dr. Keith McCroan, ORIA/NAREL; Ms. Lindsey Bender, ORIA/
Radiation Protection Division (RPD); Dr. Lowell Ralston and Mr. Edward Tupin, CHP, both of
ORIA/RPD; Ms. Schatzi Fitz-James, Office of Emergency Management, Homeland Security
Laboratory Response Center; and Mr. David Garman, ORIA/NAREL. Numerous other individuals
both inside and outside of EPA provided peer review of this document, and their suggestions
contributed greatly to the quality and consistency of the final document. Technical support was
provided by Dr. N. Jay Bassin, Dr. Anna Berne, Dr. Carl V. Gogolak, Dr. Robert Litman, Dr. David
McCurdy, and Mr. Robert Shannon of Environmental Management Support, Inc.
in
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Radiological Laboratory Sample Analysis Guide for Incidents of National Significance Radionuclides in Water
Contents
Acronyms, Abbreviations, Units, and Symbols vi
Radiometric and General Unit Conversions viii
I. INTRODUCTION 1
A. Objectives 2
B. Scope and Radiological Scenarios 3
C. Analytical Response Time 6
D. Implementation 7
E. References 7
II. RADIONUCLIDES 9
III. DISCUSSION 10
IV. CROSSWALK of Data Values 12
V. RADIO ANALYTICAL SCENARIO 1 (Identifying Samples with Highest Activities) .... 13
VI. RADIO ANALYTICAL SCENARIO 2 (Identifying Uncontaminated Drinking Water) ... 22
VII. RADIO ANALYTICAL SCENARIO 3 (Contaminating Radionuclides are Known) ... 28
Appendix I. Tables of Radioanalytical Parameters for Radionuclides of Concern 32
APPENDIX II. Example of High Radionuclide Concentration in Water (Radioanalytical Scenario
1) 38
Description 38
Event Sequence 38
Analysis Path 38
APPENDIX III. Example of Finding a Potable Water Source (Radioanalytical Scenario 2) ... 43
Description 43
Event Sequence 43
Analysis Path 43
APPENDIX IV. Radionuclide Contaminants are Known (Radioanalytical Scenario 3) 46
Description 46
Event Sequence 46
Analysis Path 47
APPENDIX V. Representative Analytical Processing Times 49
APPENDIX VI. Establishing DQOs and MQOs for Incident Response Analysis 52
APPENDIX VII. Glossary 63
IV
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Radiological Laboratory Sample Analysis Guide for Incidents of National Significance Radionuclides in Water
Figures
Figure 1 - Water Sample Scenarios and Response Phases 4
Figure 2 - Water Scenario 1 Analytical Flow 13
Figure 3 - Water Scenario 2 Analytical Flow 22
Figure 4 - Water Scenario 3 Analytical Flow 28
Figure 5 - Approximate Timeframe for Radiochemical Analyses (Radioanalytical Scenario 1) . 49
Figure 6 - Approximate Timeframe for Radiochemical Analyses (Radioanalytical Scenario 2) . 50
Figure 7 - Approximate Timeframe for Radiochemical Analyses (Radioanalytical Scenario 3) . 51
Figure 8 - A Decision Point in a Flowchart 52
Figure 9 - The Data Quality Objectives Process 53
Figure 10 - Example Illustrating Case (a). Baseline Condition (null hypothesis): Parameter Exceeds
the AAL 56
Figure 11 - Example Illustrating Case (b). Baseline Condition (null hypothesis): Parameter Does Not
Exceed the AAL 56
Tables
Table 1 - Radionuclides of Concern 9
Table 2 - Crosswalk of PAG, SDWA Limits, AAL, ADL, and «MR Values 12
Table 3 - Radionuclides with Low-Abundance Gamma Rays Not Usually Used For
Their Analysis 20
Table 4 - Beta "Only" Emitters 21
Table 5A - Analytical Decision Levels (ADL) 32
Table 5B - Analytical Decision Levels (ADL) For Gross Beta or Gamma Screening Analysis . 33
Table 6A - Required Method Uncertainties for Alpha-Emitting Radionuclides at 100-mrem AAL
When Using Radionuclide-Specific Methods 34
Table 6B -Required Method Uncertainties for Beta- or Gamma-Emitting Radionuclides at 100-mrem
AAL When Using Radionuclide-Specific Methods 35
Table 7A - Maximum Contaminant Levels (MCL) and Required Detection Levels (RDL) for Alpha-
Emitting Radionuclides in Water 36
Table 7B - Maximum Contaminant Levels (MCL) and Required Detection Levels (RDL) for
Beta/Gamma-Ray Emitting Radionuclides in Drinking Water 37
Table 8A - The DQO Process Applied to a Decision Point 54
Table 8B - Possible Decision Errors 54
Table 8C - The DQO Process Applied to a Decision Point 55
Table 8D - Values ofzj_a (or z,_^ for Some Commonly Used Values of a (or P) 56
Table 9A - DQOs and MQOs for Radioanalytical Scenario 1. Prioritization Decisions Based on
Screening 57
Table 9B - DQOs and MQOs for Scenario 1. Values Reported Externally Based on Radionuclide-
Specific Measurements 58
Table 10A - Derived Water Concentrations (DWC) Corresponding to a-Emitting Radionuclide
Analytical Action Levels 59
Table 10B - Derived Water Concentrations (DWC) Corresponding to p-Emitting
Radionuclide AALs 60
Table 11A - DQOs and MQOs for Scenario 2. Internal Lab Prioritization Decisions Based on
Screening 61
Table 1 IB - DQOs and MQOs for Scenario 2. Values Reported Externally Based on Radionuclide-
Specific Measurements 61
Table 12 - Minimum Detection Concentration Values for Various Counting Times and Sample
Volumes 62
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Radiological Laboratory Sample Analysis Guide for Incidents of National Significance Radionuclides in Water
Acronyms, Abbreviations, Units, and Symbols
(Excluding chemical symbols and formulas)
a .......
a .......
AAL
ADL
AS .....
P .......
P .......
Bq ......
CERCLA
CFR
cm ......
cpm .....
d .......
DL .....
DOE
DP .....
dpm
dps .....
DQO . . . .
DRP
DWC . . .
EDO
EPA .
Y
g
Ge
GM
GP
GPC .
GS
Gy
h
HO
H!
HPGe
1C
ICC
IND
INS
keV
L
alpha particle
probability of a Type I decision error
analytical action level
analytical decision level
alpha spectrometry
beta particle
probability of a Type II decision error
becquerel (1 dps)
Comprehensive Environmental Response, Compensation, and Liability Act of
1980 ("Superfund")
Code of Federal Regulations
centimeter
counts per minute
day
discrimination limit
United States Department of Energy
decay product(s)
disintegration per minute
disintegration per second
data quality objective
discrete radioactive particle
derived water concentration
electron
maximum energy of the beta-particle emission
electronic data deliverable
United States Environmental Protection Agency
gamma ray
gram
germanium semiconductor
Geiger-Muller detector
gas proportional
gas proportional counting/counter
gamma spectrometry
gray
hour
null hypothesis
alternate hypothesis
high-purity germanium [detector]
Incident Commander
Incident Command Center
improvised nuclear device (i.e., a nuclear bomb)
incident of national significance
thousand electron volts
liter
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Radiological Laboratory Sample Analysis Guide for Incidents of National Significance Radionuclides in Water
LBGR lower bound of the gray region
LEPD low-energy photon detector
LS liquid scintillation
LSC liquid scintillation counter/counting
MARLAP .... Multi-Agency Radiological Laboratory Analytical Protocols Manual
MARS SIM . . . Multi-Agency Radiation Survey and Site Investigation Manual
MCL maximum contaminant level
MeV million electron volts
mg milligram (1CT3 g)
mL milliliter(lCT3L)
mrem millirem (1CT3 rem)
|j,g microgram (1CT6 g)
|j,R microroengten
MDC minimum detectable concentration
min minute
MQO measurement quality objective
Nal(Tl) thallium-activated sodium iodide detector
(pUR relative required method uncertainty
PAG protective action guide
pCi picocurie (1CT12 Ci)
QA quality assurance
QC quality control
R roentgten
rad radiation absorbed dose
ROD radiological dispersion device (i.e., "dirty bomb")
RDL required detection limit
REGe reverse electrode germanium [detector]
rem roentgen equivalent man
s second
SDWA Safe Drinking Water Act
SOP standard operating procedure
Sv sievert
TEDA triethylenediamine
TEDE total effective dose equivalent
UBGR upper bound of the gray region
MMR required method uncertainty
y year
vn
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Radiological Laboratory Sample Analysis Guide for Incidents of National Significance 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
(liCi/mL)
disintegrations
per minute (dpm)
gallons (gal)
gray (Gy)
roentgen equiva-
lent 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
liters (L)
rad
si evert (Sv)
Multiply by
3.16 x 107
5.26 x 105
8.77 x 103
3.65 x 102
1
27.0
2.70 x 1Q-2
2.70 x 1Q-2
103
109
4.50 x 1Q-7
4.50 x 1Q-1
3.78
102
io-2
To Convert
s
min
h
d
Bq
pCi
pCi/g
pCi/L
Bq/L
pCi/L
pCi
L
rad
Sv
To
y
dps
Bq
Bq/kg
Bq/m3
Bq/m3
[iCi/mL
dpm
gal
Gy
rem
Multiply by
3.17x 1Q-8
1.90x 1Q-6
1.14x 1Q-4
2.74 x 1Q-3
1
3.70 x 1Q-2
37.0
37.0
io-3
io-9
2.22
0.264
io-2
IO2
Note: Traditional units are used throughout this document instead of SI units. Protective Action
Guides (PAGs) and their derived concentrations appear in official documents in the traditional units
and are in common usage. Conversion to SI units will be aided by the unit conversions in this table.
Conversions are exact to three significant figures, consistent with their intended application.
Vlll
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Radiological Laboratory Sample Analysis Guide for Incidents of National Significance Radionuclides in Water
I. INTRODUCTION
This guide deals with the analysis of water samples that may have been contaminated as the result
of a radiological or nuclear event, such as a radiological dispersion device (RDD), improvised
nuclear device (IND), or an intentional release of radioactive materials into a drinking water supply.
In the event of a maj or incident that releases radioactive materials to the environment, EPA will turn
to selected radioanalytical laboratories to support its response and recovery activities. In order to
expedite sample analyses and data feedback, the laboratories will need guidance on EPA's
expectations.
A response to a radiation release to the environment likely will occur in three phases: "early,"
"intermediate," and "recovery." Each phase of an incident response will require different and
distinct radioanalytical resources to address the different consequences, priorities, and requirements
of each phase. Some of the more important radioanalytical laboratory resources germane to incident
response and recovery consist of radionuclide identification and quantification capability, sample
load capacity, sample processing turnaround time, quality of analytical data, and data transfer
capability.
The early phase begins at the initial event and lasts for three or four days, during which data are
scarce, and pre-planned dispersion models are used. During this phase, responders are primarily
concerned with evacuating people, sheltering them in place, or restricting use of specific water
supplies. The purpose of the actions and evaluations taken during the early phase is to minimize
exposure and to prevent acute health effects. The Protective Action Guides (PAGs) for radiological
emergencies require evacuation of a population if the projected short-term total effective radiation
dose equivalent1 (TEDE) exceeds 5 rem.2 The nominal trigger for sheltering is 1-5 rem over four
days (projected avoided total effective dose). The radioanalytical resource requirements (field or
fixed laboratory) for this early phase may vary significantly depending on the timeframe, source
term radionuclide and the extent of the contamination.
The intermediate phase begins when no more radiation releases are expected, and the source term
contamination radionuclides have been qualitatively identified. In this phase, radionuclide concen-
trations, extent of the contaminated zone, and matrices (air, water, soil) required for analysis may
not be well defined. The radioanalytical resources needed will depend on the radionuclide analytical
action levels (AAL) developed for the various media important to human exposure. The AAL may
change depending upon the stage of the event, the appropriate PAGs, or risk values. The radionuc-
lide derived water concentrations (DWCs) are based on the PAGs or risk values. For the inter-
mediate phase, PAGs have been established to limit the projected radiation doses for different
exposure periods; not to exceed 2-rem TEDE over the first year, 500-mrem TEDE during the second
year, or 5 rem over the next 50 years (including the first and second years of the incident). In
addition, radionuclide concentration limits for food and water as regulated by the Food and Drug
Administration and EPA would be applicable.
'The sum of the effective dose equivalent (for external exposure) and the committed effective dose equivalent (for
internal exposure). TEDE is expressed in units of sievert (Sv) or rem.
2The common unit for the effective or "equivalent" dose of radiation received by a living organism, equal to the actual
dose (in rads) multiplied by a factor representing the danger of the radiation, "rem" stands for "roentgen equivalent man,"
meaning that it measures the biological effects of ionizing radiation in humans. One rem is equal to 0.01 Sv.
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Radiological Laboratory Sample Analysis Guide for Incidents of National Significance Radionuclides in Water
The final, or "recovery," phase occurs as part of a radiological incident site- or drinking-water-
supply remediation effort. During this final phase, when site- or drinking-water-supply characteri-
zation and remediation cleanup effectiveness is determined, there is a potential for more extensive
radiochemical analyses at the lowest radionuclide concentrations. Applicable drinking water
regulations for radionuclides (40 CFR Parts 9, 141, 142) may be used during this phase.
During all phases of an incident response, radioanalytical resources are needed for identifying the
radionuclide source terms, quantification of the radionuclides in a variety of media, and the gross
radiation screening of samples for prioritization of sample processing or for information related to
the general level of contamination. This guide has been developed to provide the Incident
Commander (1C) and the laboratories selected to analyze samples during an incident with a logical
processing scheme to prioritize sample processing in relation to the radionuclide derived water
concentrations corresponding to establishedPAGs or Maximum ContaminantLevels (MCLs)under
the Safe Drinking Water Act.
A. Objectives
This document is intended to assist those analytical laboratories that will be called upon to provide
rapid support to Agency personnel following a radiological or nuclear incident. Because EPA
recognizes that in the immediate and intermediate period following such a release, there may not
be sufficient time for the Incident Command Center (ICC) to coordinate and communicate complete
data quality objectives, measurement quality objectives, and analytical priorities to the laboratory,
this document will enable laboratories to proceed with a consistent approach to developing and
reporting appropriate data suitable for the anticipated use.
The ultimate purpose of the screening process described in this guide is to ensure that public health
is protected. The recommendations in this guide are based upon EPA's PAGs and applicable
drinking water regulations for radionuclides (40 CFR Parts 9, 141, and 142, National Primary
Drinking Water Regulations; Radionuclides; Final Rule. Federal Register 65:76707-76753,
December 7, 2000).
This document presents a series of three analytical scenarios to aid laboratories in establishing
priorities for analyzing samples received during the response to a radiological or nuclear incident.
The following table summarizes the relevant responsibilities of the 1C and the laboratory manager
during such a response.
Information Sample Method Miscellaneous Reporting Analyte Turnaround Time Procedure
Provided... Priority Uncertainty MQOs (Results and Anomalies) Selection Compliance Selection
By: 1C 1C 1C Lab 1C Lab Lab
To: Lab Lab Lab 1C Lab 1C 1C
One of the key objectives in this document is to explain the responsibilities indicated above in terms
of analytical processes. While the 1C should provide the necessary information (analytes, matrices,
measurement quality objectives) that define the scope of the laboratory's processing requirements
and results, the laboratory should ensure that the methods used have been validated and will meet
the required measurement quality obj ectives (MQOs) and the required turnaround time. It is possible
that immediately following such an event, especially when MQOs may not have been established
or provided, laboratories may receive samples without complete documentation or direction. In such
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Radiological Laboratory Sample Analysis Guide for Incidents of National Significance Radionuclides in Water
cases, laboratories may follow the procedures and examples in this document, and be confident that
their results should provide reasonable and consistent results.
This document is not meant to replace any field monitoring decisions on sample prioritization. It is
intended as a guide on how to establish priorities for samples received at the laboratory at different
times throughout the response, and it should provide to the 1C the basis for understanding the nature
and limitations of the data received from the laboratories. Familiarity with Chapters 2 and 3 of
MARLAP will be of significant benefit to the users of this guide.
B. Scope and Radiological Scenarios
Radiological incidents can be subdivided into three phases: early (onset of the event to about Day
4), intermediate (about Day 4 to about Day 30), and recovery (beyond about Day 30). This guide
concentrates on the time from the end of the early phase, through the intermediate phase and into
the recovery phase. During the early phase, analytical priorities need to address the protection of the
public and field personnel due to potentially high levels of radioactivity, and to provide for
qualitative identification of radionuclides. During the intermediate phase, the radionuclides and
matrices of concern are known qualitatively., and the quantitative levels suitable for making
decisions based on analytical action levels need to be rapidly determined. The phase of an incident
where this document will find its greatest utility is early in the intermediate phase through the end
of the recovery phase. Laboratories performing analyses must focus on rapid turnaround of sample
results and optimized sample analysis so thatthe initial qualitative aspects and concentrations related
to the appropriate AALs can be determined quickly. During the recovery phase, the screening
techniques used for samples will be of less significance because the radionuclides from the event
are likely to have been characterized already. This is represented by the lower portions of the flow-
charts, which address analyses of specific radionuclides. Potable water supplies will be evaluated
against MCLs during this recovery phase.
Three distinct radioanalytical scenarios are presented for water potentially contaminated with
radionuclides. The first two assume that the radionuclides are unknown.
The first scenario is a water supply, surface, or groundwater source highly contaminated with
an unknown quantity of yet unidentified radionuclides.
The second scenario requires that the laboratory determine whether a water source from the
affected areas and unknown source term is safe to drink.
The third scenario, where the radionuclides have been identified, occurs later during the early
or intermediate phases, and the laboratory need not waste analytical processing time trying to
identify which radionuclides are present. The decision tree focuses on establishing the priority
for processing samples based on the gross concentration screening values for the specific
radionuclides.
In Radioanalytical Scenario 1, the identity of the radionuclides and potential concentrations are
unknown. This is most likely to occur during the early phase of the event. The laboratory's priority
is to identify all the radionuclides present and their concentrations in the water sources sampled.
The need to identify safe sources of drinking water (Radioanalytical Scenario 2) will occur later in
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Radiological Laboratory Sample Analysis Guide for Incidents of National Significance Radionuclides in Water
the intermediate phase and into the recovery phase. Once all the radionuclides are identified,
Radioanalytical Scenario 3 may be used for either scenario, depending upon the direction of the 1C.
These scenarios may be applicable in different phases of the event, although as was previously
indicated, Scenario 1 is usually the early phase and Scenario 2 is late-intermediate to recovery phase.
Figure 1 depicts how these three radioanalytical scenarios relate to the response team's needs for
sample prioritization.
In the third scenario, the radionuclides have been identified. This situation can arise during any of
the phases, so while Figure 1 depicts Scenario 3 occurring during the later intermediate phase,
Scenario 3 could occur earlier. The laboratory can save time by analyzing samples for its specific
radionuclides, after it has had a gross screen to determine sample-processing priority based on its
gross concentrations. Formal evaluation of other naturally occurring radionuclides may be necessary
when assessing the water as a potential drinking water source.
As introduced earlier, PAGs establish radiation dose limits applicable to different phases of an
incident response. The drinking water PAG (expressed as a numerical dose level) indicates a level
of exposure at which protective action should be taken to prevent, reduce, or limit a person's
radiation dose during a radiological incident. The derived water concentration (DWC) is the
concentration of a radionuclide in water corresponding to the PAG dose and is used to facilitate the
application of PAGs in the radioanalytical laboratory. For example, the concentration of 137Cs in
drinking water corresponding to the 500-mrem PAG is 5.8x 104 pCi/L.
Similarly, radionuclide DWCs corresponding to other specific dose or risk value may be calculated
and applied as required. The term "analytical action level" (AAL) will be used as a general term
denoting the radionuclide concentration at which action must be taken by incident responders.
Day 3 Following Event
Early Phase
Weeks to Months Following Event
Recovery Phase
Unknown Radionuclides
(Radioanalytical Scenario 1)
Known Radionuclides
(Radioanalytical Scenario 3)
Sample
priority based on
concentration
Low*
No,
but priority set
low* by OSC
High*
Gross
quantification
Radio-
analytical
Scenario 3
priority
No, but priority set
high* by OSC
Determination of
radionuclides for MCL
*Note: "High" and "Low"
refer to processing
priorities, not activity
Figure 1 -WaterSample Scenarios and Response Phases
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Radiological Laboratory Sample Analysis Guide for Incidents of National Significance Radionuclides in Water
Decisions related to the processing and prioritization of specific samples will be made by laboratory
personnel at the laboratory by comparing the results of radioanalytical measurements to "analytical
decision level" (ADL) concentrations. Whenever the measured analyte concentration equals or
exceeds the applicable ADL concentration, it will be concluded that the AAL (PAG or risk factor)
has been exceeded.
When applied to prioritizing samples for processing, the ADL concentrations are always less than
the corresponding AAL values by an interval calculated to provide statistical confidence when
deciding whether the corresponding AAL has or has not been exceeded. The magnitude of this
interval corresponds to the maximum uncertainty that would be consistent with acceptable decision
error rates established during the data quality objectives (DQO)/MQO process.1 In this process, the
MQO of greatest significance is the required method uncertainty, UUR. An example of a dose and its
corresponding AAL, ADL, and WMR is shown here for 226Ra (based on tolerable Type I and Type II
error rates; see details in Appendix VI):
Measurement Type Dose (mrem) AAL2 (pCi/L) ADL (pCi/U u^ (nCi/L)
Screening3 100 180 90 54
Radionuclide-specific4 100 180 130 22
Laboratories will perform both gross activity measurements and radionuclide-specific measurements
during an incident. Because different DQOs and MQOs are applicable to different types of measure-
ments, different um and corresponding ADL values are provided for screening and radionuclide-
specific analyses. The default values for um and corresponding ADL for screening and radionuclide-
specific determinations presented in Tables 5A, 5B, 6A, and 6B provide laboratories with a starting
point for developing protocols and systems for incident response activities. It is anticipated that in
the case of an incident, specific DQOs and MQOs may be developed by Agency personnel to reflect
the specific nature and concerns of the incident and provided to the laboratory.
Decisions related to water quality suitable for drinking are based on specific regulatory values based
on the Safe Drinking Water Act (SDWA). In this case, specific values for the Maximum
Contaminant Level (MCL) and the Required Detection Level (RDL) are applicable for each
radionuclide, as well as gross a and P (see Tables 7A and 7B). If more than one beta- or gamma-
emitting radionuclide is present, the "sum of fractions" rule applies. This is best illustrated in the
example found in Appendix II, Scenario 1, Step 15. The "sum of fractions" rule does not apply to
alpha-emitting radionuclides.
The flow diagrams and corresponding numbered notes and data tables depict the analytical
processing suggested for rapid response and consistency. In keeping with concepts of the Multi-
Agency Radiological Laboratory Analytical Protocols (MARLAP) Manual, this guide does not
specify analytical methods. A performance-based approach for the selection of appropriate analytical
methods by the laboratory will be used to achieve MQOs specified by this document and the 1C.
'Appendix VI provides the derivation and detailed discussion of MQOs, required method uncertainties, and ADLs.
2See Appendix VI, Table 10A.
3Tables 5A and 5B in Appendix I summarize default ADLs and um for screening measurements.
4Tables 6A and 6B in Appendix I summarize default ADLs and Mm for radionuclide-specific measurements.
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Radiological Laboratory Sample Analysis Guide for Incidents of National Significance Radionuclides in Water
Radiochemical methods to support response and recovery actions following a radiological or nuclear
INS can be found in Standardized Analytical Methods for Environmental Restoration following
Homeland Security Events, Revision 3 (EPA 600-R-07-015).
MQOs are statements of performance objectives or requirements for selected method performance
characteristics. Method performance characteristics include the method uncertainty, the method's
detection capability, the method's quantification capability, the method's range, the method's
specificity, and the method's ruggedness. An example MQO for the method uncertainty at a
specified concentration, such as the AAL, could be:
"A method uncertainty of 50 pCi/L or less is required for 241Am analysis at the 100-
mrem AAL of 400 pCi/L."
The MQOs and any other analytical requirements serve as the basis for the laboratory's selection
of a method under a performance-based approach. The laboratory should have performance data to
demonstrate the method's ability to achieve the project-specific MQOs. Method validation and
continued acceptable method performance assessments are essential to the performance-based
approach to method selection.
This document presents a default set of MQOs. Actual MQOs, however, always will depend upon
events and may need to be modified by the 1C to better address a particular event. However, in order
to have an analytical approach in place to address a variety of incident scenarios, the identified
decision points in the accompanying flow diagrams refer to the default MQOsprimarily in the
form of required method uncertaintiesfor analyzing the radionuclides of concern. For example,
at most decision points in the diagrams where a quantitative value is given, a z/MR at that AAL is
identified in the notes and the tables. The UMR values are identified in Tables 5A, 5B, 6A, and 6B of
Appendix I. Appendix VI describes the methodology used to establish the required method
uncertainties identified in these tables. It is important to note that the ADL values specified in
Appendix I are less than the PAGs or AALs stated in Appendix VI, Tables 10A and 10B, by the
statistical factors identified in Appendix VI. In a few cases, an MQO in the form of a Required
Detection Limit is used. These decision points have action limits (MCLs and RDLs) that are
specified by regulation (i.e., the Safe Drinking Water Act). These are specifically identified in
Tables 7A and 7B in Appendix I. In these instances, the measured value need only be less than the
MCL to be within the limits of the regulation, and the sample-specific detection limit need only be
less than or equal to the RDL.
Once the appropriate method has been selected, then based on the required method uncertainty or
required detection limit, the laboratory can select the proper aliquant size, counting time and other
parameters to meet the MQOs in the most efficient manner.
C. Analytical Response Time
Decisions regarding the extent of contamination in surface and groundwater supplies will need to
be made in a timely manner. Approximate times required for laboratory processing of these samples
and finalizing the sample results are shown in Appendix V. This identifies the workflow for making
qualitative and quantitative measurements of high-activity contaminated water samples (Radioana-
lytical Scenario 1). In addition, results of the sample radioanalytical measurements needs to be
communicated promptly by the laboratory to the 1C so that decisions regarding movement of
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Radiological Laboratory Sample Analysis Guide for Incidents of National Significance Radionuclides in Water
population, sheltering, and additional sampling can be made.
D. Implementation
It may be necessary for laboratories to incorporate key aspects of this document into their standard
operating procedures. For example, the gross screening process will require specific standards and
response factors for each of the instruments used by the laboratory. This could be a departure from
the laboratory's current screening practice because the activity levels, sample geometries, and
matrices may be significantly different from what the laboratory normally experiences.
Laboratories should become proficient with these procedures because they could be asked to
respond to analytical requests in hours rather than weeks. Thus, laboratory personnel should become
familiar with the recommendations and procedures, and laboratories should consider both training
and actual "drills" or exercises where analytical scenarios and samples are tested during a controlled
scenario. The frequency and depth of these exercises will be at the discretion of the laboratory
management.
Laboratory personnel also should be cross-trained in different areas of the incident response
functions. This will help to ensure sample analysis continuity throughout the length of the incident
response.
Certain values are identified in the tables in this document for presumptive AALs, which may be
relied upon in the absence of explicit action levels received from the Incident Command Center, so
that the laboratory may begin to process samples promptly. However, these values may change
based on the needs of the particular event. MQOs will be stipulated by the 1C and should be
communicated to the laboratory as early as possible so that analysis can meet project objectives.
E. References
American Public Health Association (APHA), American Waterworks Association (AWWA), and
Water Environment Federation (WEF). 2005. Standard Methods for the Examination of Water
and Wastewater, 21st Edition. Available for purchase from www.standardmethods.org/. (See
note following this list for additional information on approved standard methods.)
U.S. Environmental Protection Agency (EPA). 1992. Manual of Protective Action Guides and
Protective Actions for Nuclear Incidents. Washington, DC. EPA400-R-92-001, May. Available
at: www.epa.gov/rpdwebOO/rert/pags.html.
U.S. Environmental Protection Agency (EPA). 1999. Cancer Risk Coefficients for Environmental
Exposure to Radionuclides. Federal Guidance Report No. 13. EPA402-R-99-001, September.
Available at: www.epa.gov/radiation/assessment/pubs.html.
U.S. Environmental Protection Agency (EPA). 2000. "Radionuclides Notice of Data Availability
Technical Support Document." Available at: www.epa.gov/safewater/radionuclides/pdfs/
regulation_radionuclides_rulemaking_techsupportdoc.pdf
U.S. Environmental Protection Agency (EPA). 2000. 40 CFR Parts 9, 141, and 142, National
Primary Drinking Water Regulations; Radionuclides; Final Rule. Federal Register 65:76707-
7
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Radiological Laboratory Sample Analysis Guide for Incidents of National Significance Radionuclides in Water
76753, December 7. Available at: www.epa.gov/safewater/radionuclides/regulation.html.
U.S. Environmental Protection Agency (EPA). 2001. OSWER Directive 9283.1-14, Appendix B:
"Use of Uranium Drinking Water Standards under 40 CFR 141 and 40 CFR 192 as Remediation
Goals for Groundwater at CERCLA sites." November 6. Available at: www.epa.gov/superfund/
health/contaminants/radiation/pdfs/9283_l_14.pdf.
U.S. Environmental Protection Agency (EPA). 2002. "Final Implementation Guidance for Radio-
nuclides," EPA 816-F-00-002.40 CFR 141.26(a)(2)(iii). Available at: www.epa.gov/safewater/
radionuclides/compliancehelp.html.
U. S. Environmental Protection Agency (EPA). 2003. Response Protocol Toolbox: Planning for and
Responding to Drinking Water Contamination Threats and Incidents. Interim Final - December.
Office of Water. EPA817-D-03-001 through EPA-817-D-03-007. Available at: http://cfpub.epa.
gov/safewater/watersecurity/home.cfm?program_id=8#response_toolbox.
U.S. Environmental Protection Agency (EPA). 2006. Guidance on Systematic Planning Using the
Data Quality Objectives Process (EPA QA/G-4). EPA/240/B-06/001. Office of Environmental
Information, Washington, DC. Available at: www.epa.gov/quality/qs-docs/g4-fmal.pdf.
U.S. Environmental Protection Agency (EPA). 2007a. Standardized Analytical Methods for
Environmental Restoration following Homeland Security Events. Revision 3. EPA 600-R-07-
015. National Homeland Security Research Center, Office of Research and Development.
Available at: www.epa.gov/nhsrc/pubs/reportSAM030107.pdf.
U.S. Environmental Protection Agency (EPA). 2007b. Method Validation Requirements for
Qualifying Methods Used by Radioanalytical Laboratories Participating in Incident Response
Activities. Revision 0. Office of Radiation and Indoor Air. Unpublished; undergoing final
review.
U.S. Food and Drug Administration (FDA). 1998. "Accidental Radioactive Contamination of
Human Food and Animal Feeds: Recommendations for State and Local Agencies." 13 August.
Available at: www.fda.gov/cdrh/dmqrp/84.html.
U.S. Department of Health, Education and Welfare (HEW). 1970. Radiological Health Handbook,
p.123.
U.S. Department of Homeland Security (DHS). 2004. Nuclear/Radiological Incident Annex to the
National Response Plan. NUC-1. Available at: hps.org/documents/NRPNuclearAnnex.pdf.
Multi-Agency Radiological Laboratory Analytical Protocols Manual (MARLAP). 2004. EPA 402-B-
04-001A, July. Volume I, Chapters 3, 6, Volume II. Available at: www.epa.gov/radiation/
marlap.
Multi-Agency Radiation Survey and Site Investigation Manual (MARSSIM), Revision 1. 2000.
NUREG-1575 Rev 1, EPA 402-R-97-016 Revl, DOE/EH-0624 Revl. August. Available at:
www.epa.gov/radiation/marssim/.
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Radiological Laboratory Sample Analysis Guide for Incidents of National Significance Radionuclides in Water
Approved Standard Methods for the Examination of Water and Wastewater, required for analyses
under Radioanalytical Scenario 2, include the following. Analysis of the radionuclides discussed in
the following section with procedures from other standard organizations may be acceptable (see 40
CFR 141.25 for alternative methods).
7110 Gross Alpha and Gross Beta Radioactivity (Total, Suspended, and Dissolved) (3 methods)
7120 Gamma-Emitting Radionuclides (2 methods)
7500-3H Tritium (2 methods)
7500-Cs Radioactive Cesium (2 methods)
7500-1 Radioactive Iodine (2 methods)
7500-Ra Radium (5 methods)
7500-Sr Total Radioactive Strontium and Strontium-90 (2 methods)
7500-U Uranium (3 methods)
II. RADIONUCLIDES
Table 1 lists some of the radionuclides that are believed to be accessible and possibly could be used
in a radiological dispersion device (ROD)or "dirty bomb"or used to contaminate a drinking
water supply, and which are addressed in this report.
This list is specifically for a ROD event and the maj or (noninclusive) dose-related radionuclides that
might be formed from the detonation of an improvised nuclear device (IND). In the case of a IND,
numerous short- and long-lived fission product radionuclides will be present, requiring proper
identification and quantification. Several of the radionuclides on the list have progeny that will
coexist with the parents. Thus, if 228Th is found, 224Ra also would be present (although it is not
listed). Several different radionuclides may be present even if only one ROD is used.
TABLE 1 - Radionuclides of Concern
Radionuclides
Alpha Emitters
Am-241
Cm-242
Cm-243
Cm-244
Np-237
Po-210*
Pu-238
Pu-239
Pu-240
Ra-226
Th-228
Th-230
Th-232
U-234
U-235
U-238
U-Nat
Radionuclides
Beta/Gamma Emitters
Ac-227f
Ce-141*
Ce-144*
Co-57*
Co-60*
Cs-134*
Cs-137§
H-3*
1-125*
I-129f
1-131*
Ir-192*
Mo-99f
P-32*
Pd-103*
Pu-241
Ra-228
Ru-103f
Ru-106f
Se-75*
Sr-89*
Sr-90f
Tc-99*
* No radioactive progeny or progeny not analytically useful.
f Radioactive progeny with short half-lives, and the progeny may be used as
part of the detection method for the parent.
* Radioactive progeny not used for quantification, only screening.
§ Radioactive progeny used for quantification only, not screening.
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Radiological Laboratory Sample Analysis Guide for Incidents of National Significance Radionuclides in Water
III. DISCUSSION
In order to illustrate the typical decisions and actions to be taken by a laboratory for each scenario,
examples of the three scenarios using theoretical samples and measurement results are provided in
Appendices II, III, and IV. These examples represent only three of many different possible
permutations, however, and should not be construed as limiting. Each example is keyed back to the
steps in its respective diagram and notes.
These scenarios assume that the time period from taking the sample to the actual beginning of the
analysis by the laboratory will be short (under one day). Therefore, samples received by the
laboratory will not be preserved, nor will they have been filtered. Sample filtration generally should
not be performed until the extent of contamination and the radionuclide identity(ies) are known. The
final decision on this must be communicated to the laboratory by the 1C based on the project MQOs.
Should it be necessary to delay analysis for any sample for more than two days, the sample should
be preserved according to the analysis protocols to be determined.
For the three scenarios discussed in this guide, it is assumed that field personnel have performed
some type of radiation detection survey of the samples prior to sending them to the laboratory. If
appropriate, field personnel may determine which samples are to be submitted first to the laboratory
based on these survey results. The laboratory's surveys and analyses of the samples are not intended
to confirm the field survey results.
Only qualified laboratories using validated radioanalytical methods (see EPA 2007b and MARLAP,
Chapter 6) should be used in order to process samples in a timely and effective manner. These
laboratories will have the necessary radioanalytical capability and sample-processing capacity to
conduct the required gross screening and radionuclide-specific analyses defined for the radioanalyti-
cal scenarios. This guide recommends the following analytical process flow.
1. General screening based on total radiation emitted from the sample.
2. Screening based on type of radiation emitted (i.e., alpha, beta, or gamma).
3. Specific analytical techniques applied after screening indicates the most significant activities.
This sequence is used for screening in the diagrams for each radioanalytical scenario. Each decision
point in the flow diagram relates to an AAL (based on a PAGDWC, regulation, or risk-based DWC)
that is part of the overall analytical process. The flow diagrams for the three radioanalytical
scenarios (Figures 2, 3, and 4) use simplified process-control shapes: diamonds represent decision
choices, and rectangles are action or information steps. The numerical limits in the diamonds of the
flow diagrams are ADLs. Many of the flow diagram shapes have numbers keyed to the notes
immediately following the respective figures. Most shapes are color-coded to reflect the highest
priority analytical flow path (red), intermediate (next important) flow path (green), or the lowest
priority flow path (yellow) based on the time needed to return the required analytical results to the
1C. The accompanying numbered notes are color-coded in the same fashion, as are the examples in
Appendices II, III, and IV. Consequently, it is highly advisable to study the flow paths in color, as
a black-and-white version may be confusing or ambiguous.
The screening techniques outlined in the first steps of the flowcharts assume that the laboratory
maintains the necessary instrumentation and can perform the initial gross sample screening (at or
immediately subsequent to sample receipt) functions identified below:
10
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Radiological Laboratory Sample Analysis Guide for Incidents of National Significance Radionuclides in Water
Micro-R meters for evaluating radiation exposures and doses on low-activity samples.
Dose-rate meters capable of detecting gamma-beta exposures and doses.
Hand-held gross alpha frisker for assessing the alpha count rate on sample contact.
Survey meters with appropriate alpha, beta, and gamma detector probes can be used to determine
whether samples exceed the maximum dose rate that can be handled or analyzed at the
laboratory.
The instrument used for gross screening analysis (mostly for y radiation) should be calibrated
(pCi/net dose rate) with a 137Cs source of appropriate geometry.
The laboratory also should have the instrumentation to perform radionuclide-specific analyses (e.g.,
high-purity germanium [HPGe] detectors for gamma and ion implanted silicon detectors for alpha
spectrometry). Some of the radionuclides listed in Table 1 on page 9 (e.g., 103Pd) can be detected
only with a specific type of gamma-ray detector because of their low gamma-ray emission energy
(60 keV is the usual lower energy for many HPGe calibrations).
Each numbered box has associated with it a note that provides additional detail for that particular
part of the process. Clarification is also provided in these notes as to when parallel paths of analysis
should be followed to help expedite the processing of samples.
Table 12 (Appendix VI) provides estimated counting times for LSC and GPC and the minimum
detectable concentration (MDC) that can be achieved by screening a small sample aliquant for gross
alpha and beta activity. The values are based on typical detector efficiency and background values
for two methods, gas proportional and liquid scintillation counting. Laboratories should prepare their
own MDC tables using their preferred detection method as part of their standard operating
procedures (SOPs). Laboratories also should determine (in advance) whether their individual
analytical protocols will need to be revised to accommodate this process.
The number of samples that will be analyzed, and their level of contamination, will be significantly
higher than normal samples. Laboratories must also consider the following:
Separate sets of procedures for sample handling and storage.
Increasing the frequency of detector background analyses.
Increasing the frequency of QC checks.
Consider adjusting the QC check activity level to more closely align with the activity of the
anticipated samples.
Increasingthe frequency of contamination assessments (i.e., smears/swipes) on working surfaces
in the laboratory.
Separate protocols for personnel protective equipment.
Separate protocols for personnel and sample radiation monitoring.
Separate storage location for high-activity samples or a large group of samples, which would
increase laboratory background for detectors or personnel. This storage location may need
additional shielding or be sited so as not to affect operations.
It should be noted that modern radioanalytical procedures in the United States address low ambient
concentrations of environmental radionuclides normally encountered during the past 30 years. With
the detonation of an RDD or IND involving radionuclides with radioactive progeny, it is possible
that the radioactive equilibria involved with these progeny may have been established (depending
11
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Radiological Laboratory Sample Analysis Guide for Incidents of National Significance Radionuclides in Water
on the time between creation of the radionuclide source to detonation or the time of detonation to
sampling, or both). This means that not only will there be considerably higher concentration of the
parent but of each of the progeny. Furthermore, if multiple radionuclides are involved, the cross-
contamination factor during separations must be minimized, a phenomenon that current day analysts
may not have previously experienced. A specific example of such a phenomenon would be the
elimination of 140Ba during the 90Sr separation process. Many processing schemes in today's
laboratories do not account for this step because many samples are collected over a period of weeks
to months and provided to laboratories as composites. Routine turnaround time for 90Sr analysis is
30 days. Thus, even if the 12-day 140Ba radionuclide is present, it would have decayed significantly
by the time the laboratory receives the sample for analysis.
IV. CROSSWALK of Data Values
The values corresponding to different terms referred to in this document are located in the tables
listed below:
TABLE 2 - Crosswalk of PAG, SDWA Limits, AAL, ADL, and u^ Values
500 mrem/100 mrem
(Screening)
100 mrem
(Radionuclide Specific)
SDWA MCL Values
SDWA RDL Values
DQO and MQO
Derivations
Estimated Counting
time for MDC (based on
screening analysis)
SDWA Required
Limits
Tables lOAand
10B (PAGs)
Tables 7A and 7B
Tables 7A and 7B
Table 12
AAL
Tables 10A
and 10B
(PAGs)
ADL
Tables 5A and 5B
Tables 6A and 6B
Tables 9A, 9B,
11A, and 1 IB
"MR
Tables 5A and 5B
Tables 6A and 6B
Tables 9A, 9B,
HAand 11B
EPA's Response Protocol Toolbox (EPA, 2003) provides additional recommendations concerning
planning and threat management, site characterization and sampling, and sample analysis to assist
utilities and state and local agencies. If laboratory protocols for normal or routine situations cannot
ensure that the DQOs and MQOs are achievable with the laboratory's SOPs under emergency
conditions, then a separate set of SOPs for emergency conditions will need to be developed.
12
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Radiological Laboratory Sample Analysis Guide for Incidents of National Significance Radionuclides in Water
V. RADIOANALYTICAL SCENARIO 1 (Identifying Samples with Highest Activities)
Water Sample Scenario 1
Unknown radionuclides
Priority to those samples with highest activities
1. Perform rapid sample scan
using gross (3/y instrument
Rapid lab
''scan of sample>N
2.9x104pCi/L?
(Appendix VI
Table 9a)
No
2. Rapid analysis (5 mL)
for gamma spectrometry
and gross alpha & beta
7. Rapid analysis (5
for gamma spectrometry
and gross alpha & beta
mL)"]
letry
sta |
Key
Highest priority
Second priority
Lowest priority
End result
See accompanying tables
for alpha and beta/gamma
concentrations, and
numbered notes
* Gross radioactivity
concentration for Box 1
corresponds to 137Cs
based on instrument
calibration.
3. &8.
Concentration >
1.0x103pCi/La, or
6.0x103pCi/l_p, or
0.71 xAAL for Y, or
3.9x1063H?
Appendix I
Concentration >
2.0x102 pCi/Laor
1.2x103pCi/l_p, or
7.1x AALfory, or
7.5x1053H?
Appendix I
11.
P/y ratio >
2.5?
10. Routine specific gamma
alpha, and beta analyses:
intermediate-level activity
eturn to
Step 2 or 7
12. Gross a and (3 using
250-mL aliquants by GPC
13.
Gross alpha
<15 and
gross beta
50 pCi/L
14. Routine, specific
Y, a, and (3 analyses:
Low-level activity
15.
Compares
to gross
analyses
16. Archive sample
residuals for long-
term assessment.
Contact 1C.
Analysis completed
and reviewed.
17. Archive
samples for drinking
water analyses.
Figure 2 - Water Scenario 1 Analytical Flow
13
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Radiological Laboratory Sample Analysis Guide for Incidents of National Significance Radionuclides in Water
Notes to Scenario 1: Contaminating Radionuclides Unknown
Purpose: Priority to Those Samples with Highest Activities
Highest priority samples are all analyzed first. Only after an analytical step or procedure
has been completed for the highest priority samples should lower priority samples be
addressed. The samples may arrive over several days; those with the highest priority are
always to be analyzed first. Lower priority samples (those following the green and yellow
flow paths on this chart) may need to be stored for several days until the highest priority
samples have been analyzed.
Many of the flow diagram shapes are color-coded to reflect the highest priority analytical
flow path (red), intermediate (next important) flow path (green), or the lowest priority flow
path (yellow) based on the time needed to return the required analytical results to the 1C.
The accompanying numbered notes are color-coded in the same fashion, as are the
examples in Appendix II. It is highly advisable to study the flow paths in color, as a black-
and-white printing may be confusing or ambiguous.
Analysis at this point is to assess if the 500-mrem AAL1 values are exceeded by
measurement of the sample's total gross radioactivity (concentration) with hand-held survey
instruments. These might include a survey meter or Geiger-Muller (GM) counter with
appropriately calibrated beta and gamma detector probes or a micro-roentgen meter (gamma
only).2 This step would most likely be performed with the sample container, unopened,
leaving the determination of a ADLs to the next step. Unless the identification of the
radionuclide contamination is known, the hand-held survey instrument should be calibrated
using a 137Cs source that would replicate the sample container geometry. The subsequent
measurement should be capable of identifying a concentration from zero to 5.8x 104 pCi/L,
which is the 500-mrem AAL for 137Cs. The ADL for this screening analysis is 2.9x 104 pCi/L
when applied to unknown radionuclides (see Appendix VI, Table 9A, on page 57). If the
identification of the radionuclide(s) is known, the Analytical Detection Level (based on the
AAL for the radionuclide listed for the 500-mrem value) is to be used (see Appendix I,
Tables 5 A and 5B). For survey instruments having an exposure rate readout, the instruments
should be calibrated in terms of pCi/L per exposure unit readout for each container geometry
expected and for the nuclide of interest, if known (137Cs for unidentified nuclides).
Some laboratories may also use a calibrated Nal(Tl) detector to assess gross y activity level
(using an integrated spectrum technique) and relate this measurement to a gross or
radionuclide-specific y ADL.
Some gamma-emitting nuclides may not be detected at their ADLs if the sensitivity of the
instrument used is inadequate. Tritium will not be detected, and beta-emitting radionuclides
1 Depending on the time of the response, a 2-rem PAG may be applicable. If so, values for this may be obtained by
scaling the PAGs and the ADLs by multiplying their corresponding 100-mrem values by 20. Thus the 2-rem PAG and
ADL for 137Cs would be 2.4 xlO5 and 1.2xl05, respectively.
2 Some manufacturers have developed kits that include the survey meter plus an alpha-beta-gamma pancake GM
detector and a Nal gamma detector.
14
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Radiological Laboratory Sample Analysis Guide for Incidents of National Significance Radionuclides in Water
that do not emit y- or X-rays may not be detected depending on the window thickness of the
detector.
The initial results of these measurements need to be checked against the information in the
chain-of-custody form. Communication of preliminary findings to the 1C may be very
valuable in helping the 1C determine the areas that may need additional samples. This
feedback also will reinforce the priorities assigned to each sample and further enhance
decision making.
If the gross activity scan yields a value greater than 2.9* 104 pCi/L, go to Step 2 (red path).
Otherwise, go to Step 7 (green path).
NOTE: The gross radioactivity measurements under Note 2 are evaluated against the ADLs listed
in Table 5B for 241Am, 90Sr and 60Co, respectively, at the 500-mrem level. These are not the lowest
ADL values for all radionuclides. Thus, no conclusions about the presence or absence of other
radionuclides should be made at this point in the analytical process.
If the gross a, p, or y activities of these samples indicate that an AAL may have been
exceeded (i.e., the sample activity is greater than one of these ADL values: l.OxlO3 alpha,
or 6.0><103 P, or [0.71> 10 minutes should be satisfactory for achieving the required
method uncertainties for the y-emitting radionuclides in Table 5B (counting time will meet
both the 500- and 100-mrem ADL values).
Tritium, a potential contaminant, will not be detected by either of the gross analysis scans
unless LSC is used to determine gross beta. If GPC is used for gross beta analysis, a separate
aliquant of the sample will need to be analyzed for tritium. Tritium analysis should be
'These values are based on the ADL values for241 Am and 90Sr, respectively. The assumption is that the detection device
is calibrated with 137Cs and will yield the most representative gross activity measurement at this point in the screening
process. The gamma ADL is 0.71 x AAL value for any individual gamma ray emitter.
2 LSC screening of samples typically is preferred over GPC because sample preparation of a 5-mL aliquant is much
simpler, less time-consuming, and minimizes the risk of contamination. In addition, for the same counting time, LSC
screening for this AAL has a better detection capability compared to GPC.
15
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Radiological Laboratory Sample Analysis Guide for Incidents of National Significance Radionuclides in Water
performed during this stage of the analytical process. The ADL for tritium at this stage is
3.9xl06pCi/L.
Once the rapid analyses have been performed, the data should be reviewed to verify that the
screening ADL concentrations have or have not been exceeded:
1.0 x 103 a pCi/L corresponding to 241 Am
6.0x 103 p pCi/L corresponding to 90Sr
the y-specific concentrations listed
3.9xl06for3H
(See the pCi/L values for other individual a- and p-emitting radionuclides listed in Tables
5A and 5B).
This is particularly important for a emitters, because the previous step was the first
measurement of alpha radioactivity. Note that if exceeding the ADLs is not confirmed by
at least one of the three analyses, the sample analysis reverts to the second priority analysis
path.
Sample analysis prioritization will be based upon which ADL is exceeded. The y analysis
may help to assess which of the specific radionuclide analyses needs to be pursued with the
highest priority. For example, if gross a activity exceeds the ADL and the y radionuclides
identified account for the observed gross P activity, for which no individual P- or y-emitting
radionuclide ADL has been exceeded, priority would then shift to specific a emitters. Note
in Table 5B that 57Co, 75Se,103Pd, and 125I are y-emitting nuclides only (these radionuclides
decay via electron capture) and have no contribution to the results of a gross P analysis.
In a different example, the gross P indicates an ADL has been exceeded, but the gross a
ADL was not exceeded. In this case, the P emitter analyses would take priority along with
gamma spectrometry analysis. These together would identify the specific P components of
the sample. The a analysis could be relegated to a lower priority flow path.
Some additional information may be obtained from the y-ray analysis of those radionuclides
that are principally a or p emitters and have very low abundance y rays. These types of
radionuclides may be qualitatively identified in a short count (see Table 3, page 20). Qualita-
tive identification of y rays from those types of radionuclides may aid the laboratory in
sample analysis prioritization.
High levels of P activity with no significant specific y component may warrant an additional
GPC screening technique by using mass absorbers1 to assess the p-particle energy. A sample
volume greater than 5 mL may be required to effectively assess the range of the particles by
'A technique that has been used successfully to determine the energy of beta-only emitters is to measure the range of
the beta particles in a pure material ("Feather analysis"). The ranges of beta particles in several pure materials (such as
aluminum) have already been established. The units of thickness are expressed as area! density, or mg/cm2. A set of
aluminum absorbers of varying thickness is used, and the activity versus the absorber thickness is plotted on a semi-log
scale. The linear portion of this curve is then extrapolated to find the "zero" activity thickness. This is then related to
the Epmax of the beta particle, which will be characteristic for a particular radionuclide. A discussion of this technique
can be found in Principles of Radioisotope Methodology, 3rd Edition, G.D. Chase and J.L. Rabinowitz, Burgess
(Minneapolis) 1967.
16
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Radiological Laboratory Sample Analysis Guide for Incidents of National Significance Radionuclides in Water
this method. This could minimize time spent on searching for the radionuclide (see Table
4, page 21).
Following Step 3, the highest activity samples that exceed the l.OxlO3 or 6.0><103 pCi/L
ADL screening levels (gross a or P), 3H, or specific ADL y-emitting radionuclide concentra-
tions, respectively, should be analyzed through Steps 4, 5, and 6 as quickly as possible. This
will enable the laboratory to recalibrate its gross screening methods for those radionuclides
actually found in the sample, which in turn will improve the accuracy of the gross screening
techniques in assessing whether ADLs have been exceeded for subsequent samples. This
also means that subsequent samples from the same location may be able to follow
Radioanalytical Scenario 3 (page 28).
The existence of samples exceeding the 500-mrem ADLs should be communicated to the
1C as soon as possible.
NOTE: Steps 4, 5, and 6 may be done concurrently based on the gross analysis results.
Chemical separation for specific a radionuclides commences if the gross a concentration
exceeds the ADL (see Table 5A, page 32). Certain a emitters also emit y rays or have y-
emitting decay products that may be identified in Step 3. The y results can be used to
determine which a emitter analyses need not be performed immediately. For example, lack
of a significant 59 keV peak in the y spectrum would indicate that an analysis for241 Am does
not have to be performed. If the project manager does not specify the sequence of analyses,
laboratory personnel should use their best professional judgment, based on the characteristics
of the samples, to determine the order of processing the samples so that the results are
obtained in the most efficient manner.
Chemical separations to be performed for specific P radionuclides, not identifiable via
gamma spectrometry, include 3H, 32P, 241Pu, 90Sr, and 89Sr. If the project manager does not
specify the sequence of analyses, laboratory personnel should use their best professional
judgment, based on the characteristics of the samples, to determine the order of processing
the samples so that the results are obtained in the most efficient manner.
The initial gamma spectrometry results will have identified high activity samples that may
provide insight as to which a- or p-only emitters are present. This longer count (compared
to Step 7) and optional larger sample size should focus on lower-intensity y-ray lines from
additional radionuclides. When counting is completed, the analyst should ensure that newly
identified y-rays are from different radionuclides and not just low intensity lines from the
predominant y emitters.
NOTE: Once radionuclides have been identified, gross screening methods should be recalibrated
to the radionuclides of interest, and the laboratory may follow the flowchart for Radioanalytical
Scenario 3.
7. If the initial gross screening method (Step 1) does not indicate a radioactivity greater than
the ADLs, gross a and P analyses using a 5-mL sample and a counting time of about 30
minutes should be performed to verify that these ADLs have not been exceeded. The y
17
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Radiological Laboratory Sample Analysis Guide for Incidents of National Significance Radionuclides in Water
isotopic analysis (original sample container or 5-mL aliquant) of Steps 2 and 7 using a HPGe
detector and a counting time less than 60 minutes may have a detection limit needed to
quantify radionuclides at concentrations corresponding to the 500- or 100-mrem ADLs. If
not, the sample should be counted longer.
Tritium is a potential contaminant that will not be detected by either of the gross analysis
screens unless LSC is used to determine gross beta. If GPC is used for gross beta analysis,
a separate aliquant of the sample will need to be analyzed for tritium by LSC. Tritium
analysis shouldbe performed during this stage of the analytical process. The ADL for tritium
at this stage in the analytical process is 7.5xl05 pCi/L.
8. Here the results from screening analyses performed in Step 7 are compared to the 500-mrem
ADLs from Tables 5A and 5B (a l.QxlO3 or P 6.0><103), or specific y-emitting radionuclide
ADL concentrations, respectively. If the screening concentrations are greater than these
ADLs, a high priority would be established to analyze the samples for specific radionuclides
in Steps 4, 5, or 6. If the screening results of Step 7 do not exceed the ADLs, then the
question in Step 9 is evaluated.
9. Does the gross or specific radionuclide concentration exceed the corresponding (a 200 or
P 1.2xl03)* or specific y-emitting (3.3xl03 for 60Co) radionuclide 100-mrem ADL
concentrations, respectively? If "yes," proceed immediately with subsequent analyses. The
status of samples exceeding the 100-mrem ADLs should be communicated to the 1C. If "no,"
go to Step 11.
NOTE: "*" gross concentrations noted above correspond to the 100-mrem ADL values for 241Am
and 90Sr, respectively, listed in Tables 5A and 5B. These are not the lowest concentrations for all
radionuclides, and decisions about the presence of other radionuclides should not be made until
radionuclide-specific analyses have been performed.
10. Use a routine method that can provide analytical results within about one day. Sample size
and counting time will need to be increased to verify screening levels and to quantify those
radionuclides whose individual concentrations are below their corresponding 100-mrem
ADL values listed in Tables 5A and 5B on pages 32 and 33 (see notes for Steps 4, 5, and 6
for other information on specific radionuclide analyses).
Calculate the sum of the ratios (individual nuclide concentration/100-mrem AAL are in
Tables lOAand 10B, page 59) of all radionuclide concentrations above their respective RDL
values (Tables 7A and 7B, page 36). If the summed value exceeds unity, then the 100-mrem
AAL has been exceeded even though an individual value does not exceed the ADL (see
example calculation in footnote 2 on page 41).
If the 1C does not specify the sequence of analyses, laboratory personnel should use their
best professional judgment, based on the radiological characteristics of the samples and in
order of highest to lowest concentration, to determine the order to process the samples to
produce expeditious results.
11. A P/Y ratio >2.5 (i.e., ratio of gross P to gross y) indicates that 90Sr or 89Sr may be a signifi-
18
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Radiological Laboratory Sample Analysis Guide for Incidents of National Significance Radionuclides in Water
cant contaminant. Although this decision falls into the low-priority path, this analysis should
be done first for the low-priority samples because of the dose significance of 90Sr and the
time required to do this analysis. Note that for the higher priority flow path, determination
of strontium would be done in parallel with other analyses, so the urgency of its analysis
does not need to be emphasized. Sufficient activity of the sample is necessary to have a
statistically significant P/y ratio. The summed individual y activities obtained from the
HPGe detector from the printout would need to be applied for this calculation.
12. A GPC gross a and P analysis of a larger sample (250 mL) and a longer counting time is
warranted. These analyses will determine if either of the MCL values for drinking water (15
a pCi/L or 50 P pCi/L) has been exceeded. Range determination of p-particle energy (see
footnote on page 16) may be very effective with this 250-mL sample residue. This would
help to further refine which p-only emitter is present at the highest concentration and
deserves the priority analysis.
13. Determine if any gross a, P, or y sample concentration exceeds the concentration correspon-
ding to the screening MCL. For alpha emitters, this is 15 pCi/L and for beta emitters, this
is 50 pCi/L. The status of any samples exceeding Safe Drinking Water Act standards should
be communicated to the field coordinator.
14. Routine low-level analyses including total radiostrontium should be performed if not already
done. If total radiostrontium results are greater than the ADL, use classical techniques to
identify activities of 89Sr and 90Sr separately. A longer count time y isotopic analysis should
be completed first. This will assist in the identification of a or P emitters, which may have
low abundance gamma rays. Additionally, if the y emitters are parent isotopes for other
radionuclides, this will direct the analyst on which other analyses should be performed first.
Sample size, counting time, and turnaround times shall be adjusted based on the laboratory' s
SOPs for water-compliance monitoring (see notes for Steps 4, 5, and 6 for other information
on specific radionuclide analyses).
If the gross a concentration is between 5 and 15 pCi/L, a-specific radionuclide analysis is
required to identify the radionuclides, including 226Ra. If the gross a concentration is less
than 5 pCi/L, the sample should be analyzed for 228Ra and 226Ra, and by gamma spectrometry
to verify that there are no low-activity y emitters present.
15. When the high and intermediate priority radionuclide-specific analyses are completed, verify
that no major nuclide has been missed: the sum of the individual nuclide concentrations
(excluding tritium if screening measurement was made by GPC) is approximately equivalent
to the gross activity concentration (a rule of thumb is within a range of about half to twice
the gross value). This check will ensure that the sum of the measurements compares
reasonably to the total measured gross activity. Activity concentrations due to decay
products should be included in the verification. If not yet verified, the sum of the ratios
(individual P- and y-emitter radionuclide concentration/100-mrem AAL are in Table 10B)
of all radionuclide concentrations above their corresponding RDL value (Table 7B) must be
calculated. If the summed value exceeds unity, then the 500-mrem or 100-mrem AAL has
been exceeded, even though an individual radionuclide activity value does not exceed the
respective ADL (see example calculation in Appendix II, Scenario I, Step 15).
19
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Radiological Laboratory Sample Analysis Guide for Incidents of National Significance Radionuclides in Water
16. All samples should be archived for long-term or follow-up analyses. Those samples having
radionuclide concentrations exceeding concentrations for the 100-mrem ADLs should be
checked for preservation and stored for potential future analysis.
The 1C should be notified with specific results for samples and radionuclide concentrations.
17. Archive samples for drinking water analyses. See Tables 7A and 7B for drinking water
MCLs and their required detection limits (RDLs).
Additional Points:
Analysts should recognize that when performing gross a or gross P analysis by evaporation of a
sample, a significant loss of volatile radionuclides (such as tritium and iodine) will occur. Following
this initial screening technique, the absence of any volatile radionuclides may need to be verified,
depending upon the nature of the event.
Certain a- and p-emitting radionuclides have y rays that are not used normally for analysis of those
radionuclides, and may not necessarily be identified in gamma spectrometry software. The
combination of gamma-ray abundance and half-life makes the gamma ray of little utility unless there
is a significant mass of the material or the sample is counted for a long time. It is recommended that
a separate library for incident response samples be created that has these y rays. Table 3 provides
some examples.
TABLE 3 - Radionuclides with Low-Abundance Gamma Rays Not Usually Used For Their Analysis
Radionuclide
Principal Decay
Gamma, keV
Abundance, %
Radionuclide
Principal Decay
Gamma, keV
Abundance, %
Radionuclide
Principal Decay
Gamma, KeV
Abundance, %
89Sr
P"
909
9.5 x!0~4
232Th
a
911
(from 228Ac)
27.2
241pu
P"
149
1.9xlO~4
90y
P"
1761
l.lxlO"2
235U
a
185.7
54
242pu
a
44.9
4.2xlO~2
129T
P"
40 (32 X-ray)*
7.5 (92.5)*
237Np
a
86.5
12.6
243Cm
a
278
14
2iopo
a
80.3
l.lxlQ-3
238pu
a
55.3
4.7xlO~2
226Ra
a
186 (262)*
3.3(5xlO~3)*
239pu 240pu
a a
112.9 54.3
4.8xlO~2 5.2xlO~2
228Th
a
84
1.21
241Am
a
59.5
35.7
Values in parentheses represent the next most abundant gamma ray.
These gamma rays can be used for qualitative identification of these radionuclides. Their presence
in the gamma-ray spectrum should direct the analyst to perform chemical separations followed by
alpha- or beta-specific detection.
Aluminum absorbers can be used to qualitatively identify the presence of radionuclides based on
penetrating ability. Thus, if an aluminum absorber of 6.5 mg/cm2 is used, and the measured activity
is reduced to background, one could qualitatively state that the beta particle energy of the
radionuclide is < 0.067 MeV. Conversely, if the absorber has little effect on the count rate, it can
20
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Radiological Laboratory Sample Analysis Guide for Incidents of National Significance Radionuclides in Water
be stated that the beta particle energy is >0.067 MeV. Table 4 identifies some beta-only emitters
with their energies and range in aluminum absorbers.
TABLE 4 - Beta "Only" Emitters
Radionuclide
Maximum Beta Energy, MeV
Range [2] in Aluminum,
mg/cm2 for EBmax
241Pu
0.021
0.8
63Ni
0.067
6.5
129j
0.150
27
35S
0.167
32
"Tc
0.294
75
32p
1.711
800
90Sr/90Y
(0.546)72.28 [1]
1,100
Notes:
[1] It may be assumed that 90Sr/90Y will be in secular equilibrium by the time any analysis is started. Thus,
the 2.28 MeV beta particle of 90Y will be present.
[2] U.S. Department of Health, Education and Welfare (HEW). 1970. Radiological HealthHandbook, p. 123.
21
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Radiological Laboratory Sample Analysis Guide for Incidents of National Significance Radionuclides in Water
VI. RADIOANALYTICAL SCENARIO 2 (Identifying Uncontaminated Drinking Water)
Water Sample Scenario 2
Unknown radionuclides
Priority to identifying uncontaminated drinking water
Survey meter
measures (3/y
<6.0x103
pCi/L
14a. Gross o/p analysis
of 5- or 10-mL aliquant
2a. Gross o/p analysis
of 5- or 10-mL aliquant
13. Store samples for
analysis in near future
4a. 3H analysis
Key
Highest priority
Second priority
Lowest priority
End result
See accompanying tables
for alpha and beta/gamma
concentrations, and
numbered notes
15. Store samples for
analysis much later.
May not be potable.
4a. 3H analysis
Proceed at Step 3 if
necessary.
No
No
16. Not potable-
Notify 1C
Yes
3. Analyze by GPC
with longer counting
time
P/y emitters
>15 pCi/L/Gross
results
< 5 pCi/L
13. Store samples for
analysis in near future.
Yes
7. Begin analyte-specific p analyses.
9. Gamma spectrometry
8. Begin analyte-specific
Ra and a analyses
10. Check values against MCLs
(see Tables 7A-B in Appendix I)
for specific radionuclides (Steps
4,7, 8, 9).
J 12a. Analyze for
\ total uranium
Yes
16. Not potable:
Notify 1C
Figure 3 - Water Scenario 2 Analytical Flow
22
17. Potential potable
water source: Notify 1C
-------
Radiological Laboratory Sample Analysis Guide for Incidents of National Significance Radionuclides in Water
Notes for Scenario 2: Contaminating Radionuclides Unknown
Purpose: Rapid Identification of a Potable Water Source
Highest priority samples are all analyzed first. Only after an analytical step or procedure
has been completed for the highest priority samples should lower priority samples be
addressed, he samples may arrive over several days; analysis for those with the highest
priority are always started first. Lower priority samples (those following the green and
yellow flow paths on this chart) may need to be stored for several days until the highest
priority samples have been analyzed. The samples with the highest priority in this instance
will be the ones with the lowest activity. Gross a and P, and all analyses done to assess
MCL values, must use standard methods approved for drinking water (page 9). This
scenario assumes that the sources being analyzed have already been used as potable water
sources.
Many of the flow diagram shapes are color-coded to reflect the highest priority analytical
flow path (green), intermediate (next important) flow path (yellow), or the lowest priority
flow path (olive brown) based on the time needed to return the required analytical results
to the 1C. The accompanying numbered notes are color-coded in the same fashion, as are
the examples in Appendix III. It is highly advisable to study the flow paths in color, as a
black-and-white printing may be confusing or ambiguous.
Screening with a hand-held survey instrument is to be performed as a contact reading on the
outside of the sample container. The purpose of this screen is to eliminate quickly those
samples that are obviously contaminated and thus may not be used as a drinking water
source. Appropriate instruments might include a survey meter or Geiger-Muller counter with
calibrated beta and gamma detector probes or a micro-roentgen meter (gamma only),1 using
a 137Cs source geometry that would replicate the sample container geometry. The calibration
measurement shouldbe capable of identifying a concentration down to 6.Ox 103 pCi/L, which
is half of the 100-mrem AAL for 137Cs. Laboratories will need to develop instrument-specific
calibration SOPs, which include the use of a mock sample container with a radionuclide
source.
NOTE: The next steps use screening techniques. The MDCs are used as AALs. These values are
based on those routinely achievable using the count times and volumes noted in Table 12 of
Appendix VI.
Gross alpha and gross beta screening measurements may be performed using a liquid
scintillation counter (LSC)2 or a gas proportional counter (GPC). For LSC, a 5- to 10-mL
sample is mixed with a liquid scintillation cocktail in a LSC vial and counted for
approximately 10 minutes. For GPC, a 5- to 10-mL sample is deposited on a planchet,
1 Some manufacturers have developed kits that include the survey meter plus an alpha-beta-gamma pancake GM
detector and a Nal gamma detector.
2 LSC screening of samples typically is preferred over GPC because sample preparation of a 5-mL aliquant is much
simpler, less time-consuming, and avoids possible contamination.
23
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Radiological Laboratory Sample Analysis Guide for Incidents of National Significance Radionuclides in Water
evaporated, and then counted for approximately 30 minutes. Note that, dependent upon the
type of instrument used, the count time for some analyses may be shorter with LSC than
with GPC. The total mass of evaporated residue for GPC analysis may prevent processing
a full 500 mL aliquant. In these cases, a smaller volume and longer count time will be
required.
The ADLs for this part of the analysis are based on the AAL being considered MDC values.
The ADL values are 110 pCi/L gross a and 410 pCi/L gross P concentration (see Table 11A
in Appendix VI). Table 12 in Appendix VI shows that the MDC values (210 pCi/L and 820
pCi/L) can be achieved with a 10-minute count of a 5-mL sample. Volumes and count times
may be adjusted based on laboratory-specific instrumentation.
Screening for radionuclides such as 125/129/131i will not be able to be performed by GPC unless
the samples are carefully prepared to prevent loss of radioiodines due to volatilization.
Furthermore, radionuclides that decay by electron capture (such as 57Co, 75Se, 103Pd) may not
be able to be screened using GPC. If any of these electron-capture radionuclides are present,
analysis using a low-energy photon detector (LEPD) or a specific separation scheme for each
will be required.
Tritium cannot be screened using GPC techniques, because it will most likely be present as
a tritiated water molecule. LSC should be used routinely for tritium analysis because of
tritium's very low electron energy and its likely presence as part of a water molecule. For
these reasons, tritium has a special status. If GPC analysis, and both alpha and beta analyses
are less than the ADLs, Steps 4a and 4b must be performed. If LSC analysis is used and both
alpha and beta analyses are less than the ADLs, proceed directly with Step 3.
A concentration less than the ADL for this part of the analysis110 pCi/L gross a and 410
pCi/L gross Pwill identify the samples most likely to have radionuclide concentrations that
are below the Maximum Contaminant Levels (MCLs) for natural radionuclides, as well as
anthropogenic radionuclides.
In subsequent steps, it will be necessary to show that gross a < 15 pCi/L and gross P < 50
pCi/L (40 CFR Parts 9, 141, and 142, National Primary Drinking Water Regulations;
Radionuclides; Final Rule. Federal Register 65:76707-76753, December 7, 2000).
If the results of either the gross alpha or beta analysis are greater than the ADLs for this step
(which are based on the MDCs in Table 12), the sample should be checked for preservation
and stored for analysis at a later time, to assess the presence of other radionuclides.
The gross alpha and beta results should be compared to specific limits from the Safe
Drinking Water Act (Steps 5 and 6). The analyses for gross alpha and beta at these levels
will require a larger sample volume and longer counting times. Gross a and P analysis by
GPC is a requirement of the SDWA.
NOTE: Steps 3 and 4a (4a only required when GPC analysis is done) should be done in parallel
to expedite the decision for further analyses.
24
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Radiological Laboratory Sample Analysis Guide for Incidents of National Significance Radionuclides in Water
Samples for tritium analysis may need to be either distilled or passed through an ion
exchange resin if the gross beta results indicate significant counts above background (this
could be due to naturally occurring radionuclides and still be less than MCLs). If tritium is
present above the MCL of 20,000 pCi/L, the water source is not suitable for long-term use
as drinking water.
If the high priority sample tritium result is <20,000 pCi/L, a fresh sample aliquant (~ 4 L,
portions of which will be used for separate analyses) should be analyzed for gamma, beta,
and alpha emitting radionuclides (Steps 7, 8, and 9). If tritium concentration is > 20,000
pCi/L, the water is not a suitable drinking water source (Step 16).
4C. If tritium concentration of the low priority sample is >20,000 pCi/L, the water supply is not
suitable as a drinking water source (Step 16). If tritium concentration is < 20,000 pCi/L,
preserve the sample for future analyses (Step 13).
Analysis for specific beta emitters (Step 7) will be performed if the gross beta activity is less
than 50 pCi/L. Methods used for specific beta emitters should be able to distinguish among
the various isotopes of a specific element. Gross beta activity greater than 50 pCi/L means
the source may not be suitable as a long-term drinking water supply. The sample should be
checked for preservation and stored for analysis at a later date (Step 13).
Gross alpha analysis will need to distinguish among three different levels. Gross alpha
activity between 15 and 35 pCi/L shall be analyzed for uranium contributions (Step 12). The
uranium result is subtracted from the gross alpha result to determine gross alpha exclusive
of uranium.
If gross alpha is between 5 and 15 pCi/L, alpha-specific radionuclide analysis is required to
identify the radionuclides, with 228Ra and 226Ra taking priority. After or at the same time as
these analyses, gamma spectrometry should be performed to assess presence of any gamma
emitters.
Finally, if the gross alpha is less than 5 pCi/L, the sample should be analyzed for 228Ra and
226Ra, and by gamma spectrometry to verify that there are no low-activity gamma emitters
present. The proj ect manager may request additional radionuclide-specific analysis for man-
made alpha emitters.
Chemical separation to be performed for pure p-emitting radionuclides not identifiable using
gamma spectrometry includebut are not limited to 3H (Step 4), 90Sr, 89Sr, "Tc, 241Pu, and
32P. Sr-90 and 89Sr would have the highest priority if project management guidance is not
provided. This step is done in parallel with Step 9.
Gross alpha activity between the detection limit and 15 pCi/L may indicate presence of
anthropogenic alpha emitters or naturally occurring radium radionuclides. The exact nature
of the activity should be verified, because these samples are the result of contamination.
Samples should be analyzed for 228Ra and 226Ra.
Samples for gamma spectrometry analysis should be counted long enough to meet the 134Cs
RDL of 10 pCi/L. The count time is dependent on the sample size, background, and detector
25
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Radiological Laboratory Sample Analysis Guide for Incidents of National Significance Radionuclides in Water
efficiency (this will be a laboratory-specific counting time; 1-3 hours is an approximate
value). The software library should include lines for the predominant gammas of all products
in the U and Th natural decay series as well as any anthropogenic radionuclide with a half-
life of greater than 1 day. The purpose of including these naturally occurring gamma-ray
peaks in the library is to ensure complete identification of all gamma rays. Due to
differential solubilities of the progeny of U, Th, and Ra, no assumptions or predictions can
be made regarding the presence of the parents unless specific radiochemical separations are
performed. Gamma analyses should be performed in parallel with the alpha- and beta-
specific analyses. This step is done in parallel with Step 7.
Here the results from analyses performed in Steps 4a, 7, 8, and 9 are compared to their
respective MCLs (Tables 7A and 7B, Appendix I).
If any radionuclide exceeds its MCL, the source should not be considered potable (Step 16).
For beta emitters, the sum of the ratios (individual nuclide concentration/MCL value) of all
concentrations greater than the RDL values must be calculated. If the sum of the fractions
of all P and y-emitting radionuclides present exceeds 1.0, the water source is not potable.
If gross alpha analysis in Step 6 is greater than 15 pCi/L, then perform analysis for total
uranium (i.e, total uranium present on a mass basis).
If the total uranium concentration is less than 20 pCi/L (30 [ig/L or 30 ppb), and the
corrected gross alpha activity (Gross alpha - total uranium) > 15 pCi/L, go to Step 8 and
begin 226Ra and 228Ra analyses and any other alpha analyses requested by the 1C. If the total
uranium concentration is greater than 20 pCi/L, the water source cannot be used as a potable
water supply (Step 16).
It is possible that the source may be acceptable for drinking water once radionuclide-specific
analyses are performed. This path has a secondary priority. These samples should be
checked to assess whether or not preservation, using acids or other appropriate chemical, has
been performed. If not preserved, preservation appropriate to the analyte(s) should be made
and the sample stored for potential analysis. Any decision to conduct further analyses or to
dispose sample(s) should be made by the 1C.
NOTE: The values in Step 14b correspond to the ADL values in Table 11A of Appendix VI.
14b.
14a. Samples that are greater than 6.Ox 103 pCi/L using the survey meter screening method may
contain naturally occurring radionuclides but will not be potable. Analyze an aliquant of the
sample by gross alpha and beta analysis.
If the results of either the gross alpha or beta analysis1 are greater than the ADLs, the sample
should be preserved for analysis at a later time. It will not be acceptable as a drinking water
source, but more detailed analysis may subsequently be required. If the gross alpha and gross
beta analyses are both less than 110 pCi/L gross a and 410 pCi/L gross P, tritium analysis
1 LSC screening of samples typically is preferred over GPC because sample preparation of a 5-mL aliquant is much
simpler, less time-consuming, and avoids possible contamination.
26
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Radiological Laboratory Sample Analysis Guide for Incidents of National Significance Radionuclides in Water
should be performed later (Step 4a of the yellow path).
Those samples that exceed the ADLs established for Steps 2a and 2b should be checked for
preservation and stored until all other water sources have been analyzed and found
acceptable or not acceptable. Specific radionuclide analyses may determine that the water
source is acceptable.
The water supply is not suitable as a drinking water source. At least one analysis or the sum
of the fractions of the beta emitters has exceeded the MCL for drinking water for that
radionuclide.
27
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Radiological Laboratory Sample Analysis Guide for Incidents of National Significance Radionuclides in Water
VII. RADIOANALYTICAL SCENARIO 3 (Contaminating Radionuclides are Known)
Key
p emissions only
a emissions only
u Multiple emissions
End result
See accompanying tables
for alpha and beta/gamma
concentrations, and
numbered notes
Water Sample Scenario 3
Known rad ion ucl ides
Priorities established by Incident Commander
What particle(s)
are emitted by the
sample
emission modes
3P.
No / Gross p
screen activity
high?
Perform nuchde-specific
analysis
Perform a-specific
analysis
specific analyses
>MCL
specific analyses
>ADL
Perform p-specific analysis
5P2.
Other analyses
as required
5oc1.
All other SDWA
radionuclide
analyses
5a2.
Other analyses
as required
spi
All other SDWA
radionuclide
analyses
All other SDWA
Other analyses
6P2. MQOs-
Scale using
Table 6B
Scale MQOs using
Tables 7A and 7B
Scale MQOs using
Tables 6A and 6B
9. Report results to 1C
7.
Final results
agree with screen! n
analyses
10. Verify all radionuchdes have
been accounted for; re-evaluate
results, or re-perform
analyses
Sum of fractions
9. Report results
to 1C
Figure 4 - Water Scenario 3 Analytical Flow
28
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Radiological Laboratory Sample Analysis Guide for Incidents of National Significance Radionuclides in Water
Notes for Scenario 3: Contaminating Radionuclides Known
Purpose: Support the Specific Needs of the 1C
For this scenario, "a" and "P" designate paths to be followed (and their associated notes)
when samples received from the field contain radionuclides that emit only alpha or beta
particles, respectively, and "|i" (indicating a mixture of a-, P-, or y-emitting radionuclides)
designates samples that contain either a gamma emitter or multiple emitters (alpha plus
beta).
Scenario 3 takes place when the radioactive contaminants have been well characterized.
Detailed analyses are required for the radionuclide(s) known to be in the samples, and at
the direction of the 1C. Thus, the radioanalytical process chart becomes much more
streamlined, and sample priority is based upon what is needed by the Incident Commander
at the time the samples are taken. Either high- or low-activity samples may take priority.
Because the radionuclides are known, the gross screening instruments should be calibrated
for the radionuclides of interest. This allows rapid and more accurate assessment of the
activity before the analytical separations are performed.
Many of the flow diagram shapes are color-coded to reflect the analytical flow path for
various combinations of decay modes (green for alpha, gray for beta, or brown for any two
emitters). The accompanying numbered notes are color-coded in the same fashion, as are
the examples in Appendix IV. It is highly advisable to study the flow paths in color, as a
black-and-white printing may be confusing or ambiguous.
The event that has taken place is now characterized, and the radionuclide(s) of concern have
been identified. The flowchart is trimmed to deciding which of the three different
radionuclide emissions are present. The emission mode generally determines the final
radioanalytical method(s) that will be used to assess the concentration. Generally, p-only
emitters will be analyzed by GPC or LSC, a-only emitters by either GPC or AS, and P- and
Y-emitters by gamma spectrometry. The choice is determined by what is known about the
event. If more than one type of radionuclide emitter is present, the choice is to follow the (a,
or P, or y) path.
This path is selected only if all the radionuclides from the event are a emitters. The samples
still should be screened to distinguish high from low-activity samples. The instrument used
to perform the screening analysis should be calibrated with the radionuclide of interest.
This path is selected only if all the radionuclides from the event are P emitters. The samples
still should be screened to distinguish high from low-activity samples. The instrument used
to perform the screening analysis should be calibrated with the radionuclide of interest. If
more than one radionuclide is present, the screening instrument should be calibrated with
the radionuclide that is expected to produce the lowest response. This will provide screening
results that are a more conservative estimate of the activity present for that radionuclide.
This path is selected only if the radionuclides from the event emit a combination of a, or P,
or Y emitters. The samples still should be screened to distinguish high from low-activity
29
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Radiological Laboratory Sample Analysis Guide for Incidents of National Significance Radionuclides in Water
samples. The instrument used to perform the screening analysis should be calibrated with
the radionuclide of interest.
The purpose of this step is to distinguish high-activity samples from low-activity
samples and to rank the samples in order of their activity level. The subsequent flow
paths would be selected based on the priority from the 1C. Thus, it is important that
this screening method is able to distinguish high-activity samples from low-activity
samples in a reasonably short time. Using a 1-hour count time as the maximum and
a 10-mL aliquant as the minimum, Table 12 in Appendix VI demonstrates the
capability for MDC and critical-level values that can be achieved routinely using
LSC or GPC analytical methods. Although these MDCs are not equivalent and do
not relate to a specific DWC, they are low enough to be used for screening purposes.
The samples should be numerically ranked based on their gross concentration and
processed according to the priority specified by the 1C.
NOTE: The flow of priority splits here. Either of the paths for the suffixes 1 or 2 may get
the priority. The difference is that suffix 1 is for SDWA requirements, and that suffix 2
flow path would be for IC-determined MQOs. Flow path 2 would be scaled to the
appropriate ADL based on the 100-mrem values.
The first analytical priority when this path is chosen is for the known contaminant(s)
from the event. This should use a radionuclide-specific method, and the RDL should
be less than or equal to that shown in Table 7A or 7B. This path would be chosen if
the intent was to look for potable water sources. If the event-specific contaminant is
less than its respective MCL in Table 7A or 7B, then analysis for all other SDWA
contaminants should proceed. If the event-specific contaminant concentration is
greater than its respective MCL in Table 7A or 7B, notify the 1C that this is not a
potential potable water source.
The first analytical priority when this path is chosen is for the known contaminant
from the event. This should use a radionuclide-specific method, and the ADL
concentration plus corresponding WMR value should be a multiple of the value found
in Table 6A or 6B (these tables are for the 100-mrem ADLs; the multiple would be
based on the ratio of 100-mrem value to the maximum dose for the particular event).
This path would be chosen if the direction were to identify water sources that may
cause exposure in excess of the maximum dose allowed for the event. If the event-
specific contaminant is less than its respective ADL (based on scaling of concentra-
tions and in Tables 6A or 6B), then analysis for all other contaminants of concern
should proceed. If the event-specific contaminant concentration is greater than its
respective ADL for that event, notify the 1C that this sample has exceeded the event-
specific AAL.
5at SBj 5m Perform all other radionuclide SDWA required analyses.
;2 5P2 5m Perform all other event related or requested radionuclide analyses.
6at 6Ql 6m Select the MCL values from Tables 7A or 7B to be compared with the final
30
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Radiological Laboratory Sample Analysis Guide for Incidents of National Significance Radionuclides in Water
analytical concentrations for the water sample.
Select the ADL values from Tables 6A or 6B (scaled to the AAL for the event) to be
compared with the final analytical concentrations for the water sample.
9.
Compare the final results with the screening analysis and verify that no major nuclide has
been missed: the sum of the individual nuclide concentrations (excluding tritium if the
screening measurement was made by GPC) is approximately equivalent to the gross activity
concentration (a rule of thumb is within a range of about half to twice the gross value). This
check will ensure that the sum of the measurements compares reasonably to the total
measured gross activity. Activity concentrations due to decay products should be included
in the verification. If there is a discrepancy between the summed activity concentration of
all statistically significant individual nuclide concentrations (i.e., sum all results detected at
levels greater than the RDL or for drinking water), check for errors and resolve any
discrepancies prior to proceeding.
If the sum of the fractions of all P- and y-emitting radionuclides present exceeds 1.0, verify
analyses or calculations. The sample would have concentrations that exceed the 40 CFR
limits. If the individual results and the sum of the fractions are less than their respective
limits, report results to 1C.
Several actions lead to this step:
In steps 4al3 4px, and 4\i^ the result for the event-specific radionuclide exceeded the
MCL for the radionuclide in potable water.
From Step 8, all analyses indicated that the sample is within the limits of the MCLs from
the SDWA.
In steps 4a2, 4P2, and 4|_i2, the event-specific radionuclide exceeded the ADL for the
event.
From Step 10 if the sum of fractions is greater than 1.0.
From Step 10 if gross activity and sum of individual radionuclide activities in sample do
not match within 0.5 to 2.0.
Notify the 1C of the specific final results for all samples, with a description of any
unresolvable discrepancies. All sample residuals or final counting forms should be archived
until notification to dispose of them is received.
The results from the radionuclide-specific analysis and the gross measurement should match
to within a factor of 0.5 to 2.0. If they do not, re-analysis may be required starting with the
gross-activity measurement. It is possible that either a short-lived radionuclide activity has
decayed away prior to having been analyzed, or a radionuclide analysis was missed. In either
case, the discrepancy should be resolved, which may include specific correlations for the
radionuclides from this event.
If this step is arrived at as a result of the sum of fractions being greater than 1.0, verify the
data to ensure correctness and that the gross activity and sum of individual activities are
within a factor of 0.5 to 2.0. When this review is completed, notify the 1C of results per Step
9.
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Radiological Laboratory Sample Analysis Guide for Incidents of National Significance Radionuclides in Water
Appendix I. Tables of Radioanalytical Parameters for Radionuclides of Concern
TABLE 5A - Analytical Decision Levels (ADL) and Required Method Uncertainty
For Gross Alpha Screening Analysis
Radionuclide
Gross a Screen
Am-241[3]
Cm-242
Cm-243
Cm-244
Np-237
Po-210
Pu-238
Pu-239
Pu-240
Ra-226
Th-228
Th-230
Th-232
U-234
U-235
U-238
Half-Life [1]
432.2 y
162.8 d
29. ly
18.10y
2.144xl06y
138.4 d
87.7 y
2.411xl04y
6.564xl03y
1.600xl03y
1.912 y
7.538xl04y
1.41xl010y
2.455xl05y
7.038xl08y
4.468xl09y
Additional
Emissions
Y
Y
Y
yDP
yDP
yDP
yDP
yDP
YDP
pCi/L
500-mrem P1
ADL
l.OxlO3
l.OxlO3
7.0xl03
1.3xl03
l.SxlO3
2.0xl03
65
900
850
850
460
1.3xl03
900
800
3.2xl03
3.3xl03
3.5xl03
Required
Method
Uncertainty [4'51
(«MR)
6.1xl02
6.1xl02
4.3xl03
760
8.8xl02
1.2xl03
40
550
520
520
280
790
550
490
1.9xl03
2.0xl03
2.1xl03
100 mrem P1
ADL
200
200
1.4xl03
250
290
390
13
180
170
170
90
260
180
160
650
650
700
Required
Method
Uncertainty [4' 51
(«MR)
120
120
8.5xl02
150
1.8xl02
2.4xl02
7.9
110
100
100
55
160
110
97
400
400
430
Notes:
[1] The half-lives of the nuclides are given in years (y) or days (d). DP refers to "decay products." Radionuclide above
the gray bar is default for calibrating screening instrumentation.
[2] The values in this table correspond to the numbered rectangles 2 and 7 in Radioanalytical Scenario 1.
[3] The um and ADL for241 Am are used for gross alpha screening.
[4] The relative required method uncertainty (#v) for values greater than the AALs in Table 10A of Appendix VI can
be obtained by dividing the um value in this table by the corresponding AAL value in Table 10A.
[5] The individual required method uncertainty (MMR)values in this table apply up to the corresponding values for AALs
or 100-mrem values, respectively, identified in the tables in Appendix VI. Above the values noted in the Appendix
VI tables, the relative required method uncertainty (#v)\vould apply.
32
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Radiological Laboratory Sample Analysis Guide for Incidents of National Significance Radionuclides in Water
TABLE SB - Analytical Decision Levels (ADL) For Gross Beta or Gamma Screening Analysis
Radionuclide
Beta Gamma
Screen[2]
Sr-90[2]
Co-60[2]
Ac-227+DP
Ce-141
Ce-144
Co-57
Cs-134
Cs-137
H-3
1-125
1-129
1-131
IT- 192
Mo-99
P-32
Pd-103
Pu-241
Ra-228
Ru-103
Ru-106
Se-75
Sr-89
Tc-99
Emission
Type
PY
Half-Life111
30.07 y
pCi/L
500 mrem
ADL
2.9xl04
P(PDP)
28.79 y
6.0xl03
PY
5.270 y
1.7xl04
p (a DP)
PY
PY
Y
PY
PY
weak p
Y
PY
PY
PY
P Y (Y DP)
P
Y
P
P (Y DP)
PY
PY
Y
P
BY
21.77 y
32.51 d
284.9 d
271. Id
2.065 y
30.07 y
12.32 y
59.40 d
1.57xl07y
8.021 d
73.83d
65.94 h
14.26 d
16.99 d
14.29 y
5.75 y
39.26 d
373.6 d
119.8 d
50.53d
2.11xl05v
550
l.lxlO5
1.5xl04
3.2xl05
2.2xl04
2.9xl04
3.9xl06
6.5xl03
1.7xl03
2.7xl03
6.0xl04
1.6xl05
3.0xl04
3.9xl05
5.0xl04
80
1.2xl05
l.lxlO4
3.4xl04
3.2xl04
1.2xl05
Required
Method
Uncertainty13'61
(«MR)
l.SxlO4
100 mrem
ADL
6.0xl03
3.6xl03
1.2xl03
l.OxlO4
330
6.7xl04
8.8xl03
1.9xl05
1.3xl04
l.SxlO4
2.3 xlO6
4.0xl03
l.OxlO3
1.6xl03
3.6xl04
9.7xl04
l.SxlO4
2.4xl05
3.0xl04
49
7.0xl04
6.7xl03
2.0xl04
1.9xl04
7.3 xlO4
3.3xl03
110
2.2xl04
2.9xl03
6.5xl04
4.3xl03
6.0xl03
7.5xl05
1.3xl03
330
550
1.2xl04
3.2xl04
6.0xl03
S.OxlO4
l.OxlO4
16
2.3xl04
2.2xl03
6.5xl03
6.5xl03
2.4xl04
Required
Method
Uncertainty13'61
(«MR)
3.6xl03
730
2.0xl03
67
1.3xl04
l.SxlO3
4.0xl04
2.6xl03
3.6xl03
4.6xl05
790
200
330
7.3xl03
1.9xl04
3.6xl03
4.9xl04
6.1xl03
9.7
1.4xl04
1.3xl03
4.0xl03
4.0xl03
1.5xl04
Notes:
[ 1] The half-lives of the nuclides are given in years (y), days (d), or hours (h). DP refers to "decay products." Radionuclides
above the gray bar are the default radionuclides for calibrating screening instrumentation.
[2] The AAL and associated MMR and ADL values for 137Cs are used for initial beta gamma screening analysis on sample bottle
(Step 1 in Radioanalytical Scenarios 1 and 2). The AAL and associated MMR and ADL values for 60Co concentration are
used for gross gamma measurements thereafter (see text). The AAL and associated MMR and ADL values for 90Sr are the
defaults used gross beta screening.
[3] The relative required method uncertainty (0v) for values greater than the AAL values in Table 10B of Appendix VI can
be obtained by dividing the u^ value in this table by the corresponding AAL value in Table 10B.
[4] Several nuclides in Table 5B decay by electron capture. These radionuclides cannot be detected using gross P analysis.
The electron-capture decay leads to characteristic X-rays of the progeny nuclide. The most effective way to detect the X-
rays from these electron-capture-decay radionuclides is either with a low-energy photon detector (LEPD) or a reverse
electrode germanium detector (N-type semiconductor detector). The lower energy range of these detectors is about 10 ke V.
[5] If Y isotopic analysis versus gross y analysis is used for rectangles 2 and 7 in Radioanalytical Scenario 1, comparisons
should be made to the value specific for the radionuclide found in the y analysis listed in this table.
[6] The individual required method uncertainty (MMR) values in this table apply up to the corresponding values for AALs or
100-mrem AALs identified in the tables in Appendix VI. Above the values noted in the Appendix VI tables, the relative
required method uncertainty (#v) applies.
33
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Radiological Laboratory Sample Analysis Guide for Incidents of National Significance Radionuclides in Water
TABLE 6A - Required Method Uncertainties for Alpha-Emitting Radionuclides
at 100-mrem AAL When Using Radionuclide-Specific Methods
Radionuclide
Am-241
Cm-242
Cm-243
Cm-244
Np-237
Po-210
Pu-238
Pu-239
Pu-240
Ra-226
Th-228
Th-230
Th-232
U-234
U-235
U-238
pCi/L
100-mrem ADL [1]
280
2.0xl03
350
410
550
18
250
240
240
130
370
250
230
920
920
990
Required Method
Uncertainty at or Below
100-mrem AAL [2'3'41
"MR
50
350
63
73
98
3.3
45
43
43
23
65
45
40
160
160
180
Notes:
[1] Only the 100-mrem ADL and the associated required method uncertainty (um) are shown.
[2] See Appendix VI for the rationale and methodology used in determining these values.
[3] These method uncertainties are applicable to each radionuclide when a radionuclide-specific method is used to
determine the activity result.
[4] The values corresponding to an AAL of 100 mrem were chosen for these tables. These values can be used to
conveniently scale to other project-specific AALs. For example, if a specific project had AALs at 20 mrem (one-fifth
of 100 mrem), the table values can be scaled down simply by dividing the listed values by five. Thus, for an
analytical action level of 20 mrem, the respective values for 210Po would be one fifth the values listed in Table
10A and this table:
20-mrem AAL = [100-mrem AAL / 5] = [26/5] * 5.2 pCi/L,
20-mremM^ = [100-mrem um/ 5] = [3.3/5] ~ 0.66 pCi/L
and the corresponding 20-mrem ADL would be:
20-mrem ADL = [100-mrem ADL/5] = [18/5] = 3.6
See Appendix VI for details of these calculations.
34
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Radiological Laboratory Sample Analysis Guide for Incidents of National Significance Radionuclides in Water
TABLE 6B - Required Method Uncertainties for Beta- or Gamma-Emitting Radionuclides
at 100-mrem AAL When Using Radionuclide-Specific Methods
Radionuclide
Ac-227+DP
Ce-141
Ce-144
Co-57
Co-60
Cs-134
Cs-137
H-3
1-125
1-129
1-131
Ir-192
Mo-99
P-32
Pd-103
Pu-241
Ra-228
Ru-103
Ru-106
Se-75
Sr-89
Sr-90
Tc-99
pCi/L
100-mrem ADL [1]
160
3.1xl04
4.1xl03
9.2xl04
4.7xl03
6.1xl03
8.5xl03
l.lxlQ6
1.8xl03
470
780
1.7xl04
4.5xl04
8.5xlQ3
l.lxlQ5
1.4xl04
23
3.3xlQ4
3.1xl03
9.2xl03
9.2xl03
1.7xl03
3.4xl04
Required Method
Uncertainty at or Below
100-mrem AAL [2'3'41
"MR
28
5.5xl03
730
1.6xl04
830
l.lxlQ3
l.SxlO3
1.9xl05
330
83
140
3.0xl03
S.lxlO3
l.SxlO3
2.0xl04
2.5xl03
4.0
5.8xl03
550
1.6xl03
1.6xl03
300
6.0xl03
Notes:
[1] Only the ADL of 100 mrem and the associated required method uncertainty (») are shown.
[2] See Appendix VI for the rationale and methodology used in determining these values.
[3] These method uncertainties are applicable to each radionuclide when a radionuclide specific method is used to
determine the activity result.
[4] The values corresponding to an AAL of 100 mrem were chosen for these tables and can be used to conveniently
scale to other project-specific AALs. For example, if a specific project had AALs at 20 mrem (one-fifth of 100
mrem), the table values can be scaled down simply by dividing the listed values by five. Thus, for an AAL of 20
mrem, the value for 90Sr would be one-fifth the values listed in Table 10B and this table:
20 mrem AAL = 100 mrem AAL / 5 = [2400/5] = 480 pCi/L
20 mremu^ = 100 mremuMK/5 = [300/5] = 60 pCi/L
and its corresponding ADL would be:
20 mrem ADL = 100 mrem ADL / 5 = [1700 / 5] = 340 pCi/L
See Appendix VI for details of these calculations.
35
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Radiological Laboratory Sample Analysis Guide for Incidents of National Significance Radionuclides in Water
TABLE 7A - Maximum Contaminant Levels (MCL) and Required Detection Levels (RDL)
for Alpha-Emitting Radionuclides in Water
Radionuclide
Gross a Screen
Am-241
Cm-242
Cm-243
Cm-244
Np-237
Po-210
Pu-238
Pu-239
Pu-240
Ra-226 [3]
Th-228 [3]
Th-230
Th-232
U-234
U-235
U-238
U-Nat
Drinking Water
MCL [11
pCi/L (mg/L) [21
15
15(4.4xlQ-9)
15(4.5xlQ-12)
15(3.0xlO-10)
15(1.8xl(r10)
15(2.2xlQ-5)
15(3.3xlQ-12)
15(8.9xlO-10)
15(2.4xlQ-7)
15(6.6x10-*)
5(5.1xlO-10)
15(1.8x10-"
15(7.3xlQ-7)
ISfl^xlO-1)
20(3.0xl(T2)
20(3.0x10-2)
Drinking Water
RDL[S1
pCi/L (mg/L) [21
3 M
1.5(4.4xlO-10)
1.5(4.5xlO-13)
1.5(3.0x10-")
1.5(1.8x10-")
1.5(2.2xlQ-6)
1.5(3.3xlQ-13)
1.5(8.9x10-")
1.5(2.4xlQ-8)
1.5(6.6xlQ-9)
1.0(1.3xlO-10)
1.5(1.8xlO-12)
1.5(7.3xlQ-8)
1.5(1.4xlO-2)
2.0(3.0xlQ-3)
2.0(3.0x10-3)
Notes:
[1] Continuous intake.
[2] Value in parenthesis is mass concentration units, (ppm).
[3] Combined concentration of 228Ra and 226Ra not to exceed 5 pCi/L.
[4] Value for RDL taken from 40 CFR141.26(a)(2)(iii). See "Final Implementation Guidance for Radionuclides," EPA
816-F-00-002, March 2002. Available at: www.epa.gov/safewater/radionuclides/compliancehelp.html.
[5] RDL value taken as 1/10 of the MCL value if not otherwise specified in the regulations.
36
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Radiological Laboratory Sample Analysis Guide for Incidents of National Significance Radionuclides in Water
TABLE 7B - Maximum Contaminant Levels (MCL) and Required Detection Levels (RDL)
for Beta/Gamma-Ray Emitting Radionuclides in Drinking Water
Radionuclide
Gross P Screen
Ac-227+DP [4]
Ce-141
Ce-144
Co-57
Co-60
Cs-134
Cs-137
H-3
1-125
1-129
1-131
IT- 192
Mo-99
P-32
Pd-103
Pu-241
Ra-228 [3]
Ru-103
Ru-106
Se-75
Sr-89
Sr-90
Tc-99
Drinking Water
MCL [11
pCi/L (mg/L) [21
50
15
300(1.1x10-")
29, 30[4](9.4xlO-12)
1,000 (1.2xlO-10)
100(8.8x10-")
80(6.2x10-")
200(2.3xlQ-9)
2.0xl04(N/A)
30(1.7xlQ-12)
1(5.7x10^)
3(2.4xlQ-14)
100(1.1x10-")
600(1.2xlO-12)[5]
30(1.0xlO-13)[5]
900(1.2xlO-")[5]
300(2.9xlO-9)[5]
5(1.8x10-")
200(6.2xlQ-12)
30(9.1xlQ-12)
900(6.2x10-")
20(6.9xlQ-13)
8(5.8x10-")
900(5.3xlQ-5)
Drinking Water
RDL [6]
pCi/L (mg/L) [21
5.0
1.5
30(l.lxlQ-12)
2.9, 3.0(9.4xlQ-13)
100(1.2x10-")
10(8.8xlQ-12)
10(7.8xlQ-12)
20(2.3xlO-10)
1,000(N/A)[7]
3.0(1.7xlQ-13)
0.1(5.7xlQ-7)
1.0(8.0xlO-15)[7]
10(l.lxlO-12)
60(1.2xlQ-13)
3.0(1.0xlO-14)
90(1.2xlQ-12)
30(2.9xlO-10)
1.0(3.7xlO-12)[7]
20(6.2xlQ-13)
3.0(9.1xlQ-13)
90(6.2xlQ-12)
10(3.4xlO-13)[7]
2.0(1.4xlO-")[7]
90(5.3xlQ-6)
Notes:
[1] Continuous intake.
[2] Value in parenthesis is mass concentration units (ppm).
[3] Combined concentration of 228Ra and 226Ra not to exceed 5 pCi/L.
[4] Includes decay products originating from the 227Ac in the body. Used only to calculate the concentration (pCi/L) or
dose from 227Ac in the body. DP refers to "decay products."
[5] Value from OS WER Directive 9283.1 -14, Appendix B: "Use of Uranium Drinking Water Standards under 40 CFR
141 and 40 CFR 192 as Remediation Goals for Groundwater at CERCLA sites." November 6, 2001. Available at:
www.epa.gov/superfund/health/contaminants/radiation/pdfs79283_l_14.pdf..
[6] RDL value taken as 1/10 of the MCL value if not otherwise specified in the regulations.
[7] RDL value taken from "Radionuclides Notice of Data Availability Technical Support Document,"(March 2000).
Available at: www.epa.gov/safewater/rads/tsd.pdf. 40 CFR 141.26(a)(2)(iii). See "Final Implementation Guidance
for Radionuclides," EPA 816-F-00-002, March 2002. Available at: www.epa.gov/safewater/radionuclides/
compliancehelp. html.
37
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Radiological Laboratory Sample Analysis Guide for Incidents of National Significance Radionuclides in Water
APPENDIX II. Example of High Radionuclide Concentration in Water (Radioanalytical
Scenario 1)
Description
Surface water, storm water, drinking water, and estuaries have been impacted by an RDD. The
specific radionuclides causing the radiological incident have not yet been determined, nor has their
concentration in these samples. The event sequence in the laboratory assumes a single analyst
following the analytical process chart, under conditions of single process stream. Analysis at this
point is to assess if the 500-mrem AAL1 values are exceeded by measurement of the sample's total
gross radioactivity with hand-held survey instruments. These might include a survey meter or
Geiger-Muller counter with appropriately calibrated beta and gamma detector probes or a micro-
roentgen meter (gamma only).2 This step would most likely be performed with the sample container,
unopened, leaving the determination of a AAL values to the next step. Unless the identification of
the radionuclide contamination is known, the hand-held survey instrument should be calibrated to
respond to a gross screening P and y concentration of 5.8* 104 pCi/L; a 137Cs calibration source
should be used. If the identity of the radionuclide(s) is known, the ADL for the radionuclide listed
for the 500-mrem value is to be used (see Table 5B, page 33). For survey instruments having an
exposure rate readout, the instruments should be calibrated in terms of pCi/L per exposure unit
readout for each container geometry expected and for the nuclide of interest (137Cs for unidentified
nuclides).
Event Sequence
It is Day 1 of the event. The incident responders have established a field office for coordinating
response efforts, including a laboratory project manager. At 1200 hours of Day 1, the incident-
response team sends a laboratory three water samples taken from the affected area that they believed
to be significantly above background radiation levels. The samples arrive at the laboratory at Day
1, 1500 hours.
Analysis Path
Laboratory personnel perform an initial scan of the three 1 -liter sample containers using a hand-held
survey meter with appropriate detector probe obtaining the data in the table below. The average beta
detection efficiency is 30%, and one may assume that the probe responds only to 10% of the decays
from the sample bottle. Thus, the overall beta-detection efficiency for this scanning technique is
3 %. The overall gamma survey instrument response (a Nal(Tl) detector) conversion factor for this
sample geometry (i.e., the one-liter sample bottle) is 53.6 pCi/(|J,R/h).
1 Depending on the time of the response, a 2-rem PAG may be applicable. If so, the radionuclide concentrations
corresponding to the 2-rem PAG D WC can be calculated by taking the values for the 100-mrem column in the table and
multiplying by 20.
2 Some manufacturers have developed kits that include the survey meter plus an alpha-beta-gamma pancake GM
detector and a Nal gamma detector.
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Radiological Laboratory Sample Analysis Guide for Incidents of National Significance Radionuclides in Water
Container ID
1
2
3
Background
Gross Beta, cpm
5,100
470
300
300
Gross Gamma, jiR/h
1,175
57
35
35
Alpha analysis has not yet been performed on these samples. The sample measurements from the
above table are converted to units comparable to those in Table 6A for Container 1 having a 1-L
volume as follows:
Gross Beta Activity =
(5100-3 00) cpm
= 72,070 pCi/L
and
(3.7x 10"2dps/pCi)x60s/min x 0.03
Gross Gamma Activity = (1,175-35 p,R/h) x ( 53.6 pCi / p,R/h) = 61,104 pCi/L.
The gross beta result exceeds the screening ADL of 2.9x 104 pCi/L, and the gamma value exceeds
the gross screening gamma ADL for 137Cs in Table 5B (4.1><104 pCi/L), which take the sample
priority to the ^| flow path for Container 1, Step 2, of Figure 2 (page 13).
A similar analysis for Container 2 yields 2,552 pCi/L beta and 1,179 pCi/L gamma. This takes us
to the green flow path for Container 2 because it is less than the gross screening value of 2.9* 104
pCi/L. Container 3 is measuring the equivalent of background dose rates, and at this point would be
relegated to the yellow flow path. The time is Day 1, 1600 hrs.
| A 5-mL aliquant of Container 1 is taken for gross alpha/beta analysis by liquid
scintillation counting and gross gamma by Na(I)Tl. The net 15-min count rate for beta is 9.25x 102
cpm (corrected for full open window efficiency of 0.60, yields 1.38><105 pCi/L), and for alpha is
1 14x1 o2 cpm (corrected for full open window efficiency of 0.10, yields 1.02><105). The laboratory
compares the pCi/L values with those in Tables 5 A and 5B. The laboratory personnel will find that
both alpha and beta values exceed the maximum ADL concentration listed (241 Am for alpha and 90Sr
for beta).
The laboratory notes that the liquid scintillation gross beta counts far exceed the survey instrument
gross beta counts. This indicates the presence of low energy beta emitters that would not be detected
by a survey instrument.
The gross gamma count of 2.65><102 cpm (corrected for 85% efficiency to 2.8><104 pCi/L) is also
greater than the ADL concentration in Table 5B (1.6xl04 for 60Co). The well Nal(Tl) detector
display indicates the presence of several gamma ray peaks in the spectrum. The sample stays on the
fast track |(red) for analysis.
The time is Day 1, 1700 hours.
Step 3, Container 1. The laboratory compares the results of the Step 2 screening analyses with the
500-mrem ADL concentrations for screening in Tables 5A and 5B and determines that ADL
concentrations have been exceeded for Container 1 for all three classes of analytes (a, p, and y).
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Radiological Laboratory Sample Analysis Guide for Incidents of National Significance Radionuclides in Water
The laboratory manager promptly notifies the 1C that initial screening indicates that the 500-mrem
AAL concentrations may have been exceeded for Container 1.
A sub-sample (aliquant) would be taken for each class of analysis (three total). While the digestions
of the sub-samples for alpha (Step 4) and beta (Step 5) specific analyses are being performed, the
third sample will be counted on an HPGe detector for about 1 hour (Step 6) for specific gamma ray
identification.
The gamma spectrum will show net activity in several gamma peaks: 186, 295, 352, 609, 1,120, and
1,764 keV. These gamma peaks will be significantly above detector backgrounds for these energies,
which correspond to 226Ra (and 214Pb/214Bi progeny of 222Rn and 226Ra). This suggests to the analyst
at least that 226Ra is present. Activity estimates for 226Ra can be made from the gamma-spectrometry
data for the 186-keV peak. Due to the diffusion of 222Rn from water, it is expected that equilibrium
between 226Ra and 222Rn (and decay progeny) in the water sample will not be attained. As such, the
226Ra activity estimates from the 226Ra/222Rn progeny photopeaks 295, 352, 609, 1,120, and 1,764
keV will be biased low. However, it will show that the total beta activity does not come from only
the contribution of the radium progeny. The time is Day 1, 1830 hours.
NOTE: No peak at 661 keV for 137Cs is found. The survey instruments used for screening analysis should
be recalibrated with a gamma emitter that more closely matches the gamma energies of the 214Pb/Bi
radionuclides.
It must be kept in mind that the gamma spectrum has eliminated the possibility of 131I and 137Cs, for
this sample. However, tritium must be analyzed specifically, as its presence cannot be detected with
the initial survey instruments and may be obscured during the gross liquid scintillation analysis due
to the presence of the other beta emitters in high concentrations (see caution about beta mismatch
in the preceding note about Step 2). Thus, an aliquant of the original sample or that used for the
gamma spectrometry should be distilled, and the distillate analyzed for tritium. Sample analysis for
tritium indicates 80,000 pCi/L tritium present at Day 1, 1930 hours.
When the alpha- and beta-specific analyses are completed, only 90Sr at 8,000 pCi/L, 226Ra at 28,000
pCi/L (and their respective progeny) and 3H at 80,000 pCi/L are found. It is important to note that
the total gamma activity from 226Ra and its decay products is only about 80% of the total beta
activity from these radionuclides. This is due to the low abundance of the gamma rays from this
group of radionuclides.
Step 15, Container 1. These values are reviewed and are within about 25% of predicted from the
gross analysis performed in Step 2. The value for 226Ra exceeds the 500-mrem ADL concentration
of 460 pCi/L, 90Sr value exceeds the 500-mrem ADL concentration of 6.Ox 103, and 3H exceeds the
20,000 pCi/L MCL from the SDWA. These results are transmitted to the Incident Command Post.
The time is Day 1, 2030 hours.
The remainder of the original sample is preserved, potentially for future analysis. The analysis of
the container with the next highest priority based on dose would now proceed.
Step 7, Container 2. This container has initial measurements of 470 cpm beta and 57 |aR/h gamma
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Radiological Laboratory Sample Analysis Guide for Incidents of National Significance Radionuclides in Water
corresponding to 2,552 pCi/L1 gross beta and 1,179 pCi/L gross gamma. It will follow the green
flow path from Step 1. The analysis of a 5-mL aliquant for a 15-minute gross alpha/beta count by
liquid scintillation will proceed.
Steps 8 and 9, Container 2. Step 7 yields a gross alpha value of 2.8x 1CT1 cpm (corrected for full
open window efficiency of 0.10, yields 2.52* 102pCi/L) and gross beta value of 17 cpm (corrected
for full open window efficiency of 0.60 , yields 2.55><103 pCi/L). These, when compared to the
values in Tables 5 A and 5B, verify that the 500-mrem ADL concentrations have not been exceeded,
but the 100-mrem ADL screening values of 2.Ox 102pCi/L (based on 241Am) and 1.2* 103 (based on
90Sr) have been exceeded. The time is Day 1, 2100 hours.
Step 10, Container 2. Analysis of alpha, beta, and gamma-specific radionuclides begins. Gamma
spectrometry indicates no gamma rays are present except for those from 226Ra progeny. The time is
Day 1, 2230 hours.
The aliquant from Container 2 is analyzed for tritium directly and found to contain 1800 pCi/L. The
time is Day 1, 2330 hours.
First results from the alpha- and beta-specific analyses are completed. The time is Day 2, 0300
hours.
All alpha- and beta-specific analyses are completed. Supervisory review of results is completed,
identifying the presence of 226Ra (6.3 x 101 pCi/L) and 90Sr (3. Ox 102 pCi/L). The time is Day 2, 1300
hours.
Steps 15 and 16, Container 2. Comparison of the gross alpha and gross beta to the sum of the
alpha- and beta-emitting radionuclides matches to within 30%. None of the individual values of the
identified radionuclides exceed their respective 100-mrem ADL concentration. Nor does the sum
of the fractions of the P- and y-emitting radionuclides (0.126) exceed the aggregate AAL (l.O).2
Thus neither exceeds the 100-mrem level. Results are reported to the Incident Commander. The
remainder of the original sample is preserved for future analysis. The analysis of the container with
the next highest priority (based on dose) would now proceed. The time is Day 2, 1500 hrs.
Step 11, Container 3. Initial micro-R or survey meter screening of this sample resulted in a dose
rate equivalent to background, and the sample aliquants analyzed by LSC also were equivalent to
1(470-300)/[(0.03)(2.22) = 2,552 pCi/L beta, (57-35)[53.6 pCi/ (|iR/h)] = 1,179 pCi/L gamma
2The sum of the fractions is calculated as follows using the values from Tables 10A and 10B (Appendix VI) under the
100-mrem level (green) columns (Note that the contribution from a emitters is not included as part of the sum of
fractions.):
Radionuclide
3H
90Sr
Sum
Table 10A
or 10B Value
(pCi/L)
1.5xl06
2.4xl03
Sample Concentration
From Radioanalytical Scenario
(pCi/L)
l.SxlO3
3.0xl02
Fraction
1.2X1Q-3
1.25X10"1
0.126
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Radiological Laboratory Sample Analysis Guide for Incidents of National Significance Radionuclides in Water
background in the short count. Following Step 9 on the decision tree, the gross beta-to-gamma ratio
(Step 11) is calculated for a 10-15-mL aliquant of the sample (dried onto a planchet) and counted
with a hand-held device. (It also would be possible to use the gross count data from the LSC and
gamma spectrometry analyses to compute this value if more convenient for the analyst.) If the ratio
is greater than 2.5, there is a strong possibility that 90Sr is present and that analysis should be
immediately initiated. Due to the low activity in this sample, it is unlikely that it has been affected
by the event, but it is prudent to determine whether if abnormal levels of 90Sr are present. Due to the
low activity in this sample, it is unlikely that it has been affected by the event. It is preserved, and,
if necessary, analysis may be resumed later at Step 12. The time is Day 2, 1600 hours.
Steps 12 and 13, Container 3. A 250-mL aliquant of the sample is counted by GPC to assess the
gross alpha and beta values with respect to the maximum contaminant level (MCL). If gross alpha
or gross beta is greater than 5 or 50 pCi/L, respectively, then the radionuclide-specific analyses
should be performed if deemed necessary by the 1C. If both are less than these values, the remainder
of the original sample should be archived for analysis at a later time (Step 17). If this sample is less
than both 5 and 50 pCi/L for alpha and beta, respectively, then it may be suitable as a drinking water
source, and further analysis would be required. The actual gross alpha and beta results are 2 and 5
pCi/L, respectively. The time is Day 2, 1800 hours.
Steps 14 and 15, Container 3. The sample analyses have been completed for all alpha, beta and
gamma emitters. Only traces of strontium above background (0.5 pCi/L) have been detected. The
results are reviewed and transmitted to the 1C. The time is Day 2, 2100 hours.
Elapsed time from receipt of samples at laboratory: 30 hours.
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Radiological Laboratory Sample Analysis Guide for Incidents of National Significance Radionuclides in Water
APPENDIX III. Example of Finding a Potable Water Source (Radioanalytical
Scenario 2)
Description1
During the intermediate phase following the detonation of an RDD, sources of potable water will
need to be evaluated for radioactive contamination. For this scenario, the priority switches from the
high priority for high-activity samples (clearly not potable) to high priority for low-activity samples.
Thus, all water samples are screened for gross alpha and beta radioactivity based on the MCL
screening levels, and those samples having gross radioactivity concentrations below the MCL have
priority for specific contaminant analyses. The radionuclide contaminants that initiated the incident
should have been completely characterized by now under "Radioanalytical Scenario 1," and their
results would lead into the specific radioanalytical processes. However, it is possible that the water
sources may have other radionuclide contaminants, either related to the initial incident or from
naturally occurring sources, which also will need to be characterized. It is important to note that the
priority flow path for this scenario is set up the opposite of Radioanalytical Scenario 1: the high
priority flow path is for those samples that have very low activity. Additionally the flow diagrams
are based on the concept of establishing the MDC as the AAL. Thus, the values for the ADLs are
calculated using Tables 11A and 12 in Appendix VI.
Event Sequence
It is Day 8 following an RDD event. The intermediate phase of the event is ongoing. The Incident
Command Center has dispatched three samples to be assessed for their potential as drinking water
sources for population areas where people will be returning to live.
The time frame for results is not as critical as in Radioanalytical Scenario 1, but prompt identifica-
tion of drinking water sources is important in rebuilding public confidence in the cleanup effort. The
only radionuclides that have been identified in any of the samples to date are 226Ra (and its progeny),
3H, and 90Sr. The beta survey meter has been calibrated with a 90Sr-specific source, and an overall
efficiency for a 1 liter sample geometry is found to be 8%. The response of the micro-R meter to a
radium source has been found to be 70 pCi/(|J,R/h).
The three samples arrive at the laboratory at 0800 on Day 8.
Analysis Path
The three samples are screened upon arrival using a micro-R meter and a beta survey meter, yielding
the following results based on the instrument specific calibrations:
Sample
Container
Gross Beta, cpm
|iR/h
Container
5
2,300
38
Gross
pCi/L
11,261
210
Container
6
300
36
Gross
pCi/L
0
70
Container
7
300
35
Gross
pCi/L
0
0
Instrument
Background
300
35
'The events and radionuclides for Radioanalytical Scenario 2 are unrelated to Radioanalytical Scenario 1.
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Radiological Laboratory Sample Analysis Guide for Incidents of National Significance Radionuclides in Water
Container 5 is greater than the 100-mrem ADL concentration for 90Sr (see Table 6B) and is set aside
for analysis at a later date. Containers 6 and 7 are less than any 100 mrem values except for 228Ra.
Steps 2a and 2b, Containers 6 and 7. The potential radionuclides are 226Ra, 3H, and 90Sr. An 8-mL
aliquant of each sample is counted for 100 minutes on a gas proportional counter (GPC) with the
following results. (See Appendix VI, Table 12, for approximate counting times. Laboratory
personnel should use specific correction factors from their instruments to determine these times).
Sample
Container
GPC cpm, alpha
GPC cpm, beta
Container
6
0.04
145
Container
7
0.02
12.3
Reagent Blank
Background
0.02
4.5
Container 6 gross beta result is greater than 10,000 pCi/L, and the high GPC result compared to the
beta screening result indicates a low energy beta emitter. Therefore, it is checked for preservation
requirements and stored for analysis in the near future (next day or two), continuing at Step 13.
Container 7 has a gross beta concentration of 84 pCi/L. This is possibly a potable water source
depending upon the specific radionuclides contained in the sample. An aliquant is removed for
tritium analysis (Step 4a), and will also be assessed using Steps 3,4b, and 6. It is Day 9, 0900 hours.
Step 4b, Container 7. This analysis from Step 4a should be started prior to taking any other steps.
An assessment of whether or not the ADL for tritium has been exceeded can be determined using
LSC in about 40 minutes. For this sample, the tritium concentration is determined to be 580 pCi/L
(the ADL for the analysis was determined to be 410 pCi/L). This confirms that Steps 3, 5, and 6
should proceed. It is Day 9, 1400 hours.
Steps 3, 5, and 6, Container 7. Due to the low reading on the micro-R or survey meter in Step 1,
a larger sample size was taken for the sample in Step 2b. In order to approximate the RDL values
in the SDWA, the lab selects a sample size commensurate with its normal water quality programs.
Looking ahead to Step 6, the sample follows the path "5-15 pCi/L" to the next step, "Begin
radionuclide-specific alpha analysis" (Step 8). Also, Step 5 divides at the 50 pCi/L level,
significantly above this sample, so the next step is "begin radionuclide-specific beta analyses" (Step
7). Beta-specific and gamma analyses should be performed in parallel.
The alpha- and beta-specific analyses are completed, yielding values for 226Ra of 3.6 pCi/L and for
90Sr of 1.2 pCi/L. It is Day 10, 1200 hours.
Step 9, Container 7. While beta- and alpha-specific analyses are being performed, gamma
spectrometry also should be performed on this sample. Dependent on detector efficiency and sample
size used, the count time will be between about 1 to 4 hours. No gamma-ray emitters are identified
in this sample, except for 214Pb/214Bi. Ra-228 analysis also is performed, and results are 1.1 pCi/L.
It is Day 8, 1800 hours.
Steps 10 and 11, Container 7. The results from Steps 4b, 7, 8, and 9 are checked against the MCL
and for Container 7. All are below the MCLs. The sum of the fractions of the MCLs for all beta-
gamma radionuclides determined (3H and 90Sr) is 0.179. The value for 226Ra + 228Ra is 4.7 and is less
than the MCL for drinking water. Because these values are less than their respective limits, the water
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Radiological Laboratory Sample Analysis Guide for Incidents of National Significance Radionuclides in Water
may be acceptable as a potable water source. However, the laboratory should continue with all
remaining samples because a single radiologically potable water supply may not be adequate. The
analysis results are sent to the Incident Command Center. It is Day 8, 2300 hours.
Step 13, Container 6. Although this sample had a low overall micro-R or survey meter reading,
it was preserved because of its statistically significant count rate above the reagent blank reading.
The process, based on a time priority, would now pick up with this sample at Steps 4a and 4b.
Step 4a, Container 6. Tritium analysis is started on this sample while preparations are begun for
specific alpha, beta, and gamma spectrometry analysis. Tritium in the sample is measured at 7,780
pCi/L. The time is Day 8, 2400 hours.
Step 3, Container 6. The gross beta value is -20 pCi/L (Step 5, the majority of the original LSC
response in Step 2 coming from tritium), and the gross alpha value is ~9 pCi/L (Step 8).
Step 5, Container 6. The gross beta concentration is less than 50 pCi/L, so beta-specific and
gamma analyses should be performed (Steps 7 and 9). Gamma spectrometry indicates no other
gamma emitters except for 214Pb/214Bi. Beta analyses indicate the presence of 90Sr at 6.0 pCi/L. The
time is Day 9, 0400 hours.
^Steps 6 and 12, Container 6. The gross alpha indicates that it is not necessary to determine if
uranium is present (Steps 12a and b). However, due to the nature of the event, uranium analysis by
inductively coupled plasma-mass spectrometry is performed and subsequently shows that total
uranium to be 2.7 pCi/L. The 1C has requested that additional alpha specific analyses should be
performed just to ensure that no other radionuclides are present (Step 8). It is Day 9, 0200 hours.
Step 8, Container 6. Alpha-specific analysis is performed for 226Ra and indicates <1.5 pCi/L.
Steps 10 and 11, Container 6. None of the MCLs for the identified radionuclides, or the gross
alpha or beta MCLs, has been exceeded. However, the sum of fractions is 1.139 form tritium and
strontium. Results reported to the Incident Command Center. The time is Day 9, 1000 hours.
Steps 14a and b, Container 5. A 10-mL aliquant is taken from Container 5 for gross alpha and
beta analysis by GPC. After counting, the values are gross alpha 3.88 pCi/L and gross beta 4.6* 104
pCi/L. The high LSC beta value compared to the screening analysis indicates a low energy beta
emitter is present. It is Day 9, 1800 hours.
Steps 4a and c, Container 5. LSC is performed on the sample for tritium and found to contain
35,000 pCi/L. As this is above the MCL for tritium, this sample is not suitable for drinking water.
The result is reported to the 1C. Other radiochemical analyses would be performed as necessary
based on the requests from the 1C.
The time is Day 9, 1900 hours.
Elapsed time from receipt of samples at laboratory: 35 hours.
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Radiological Laboratory Sample Analysis Guide for Incidents of National Significance Radionuclides in Water
APPENDIX IV. Radionuclide Contaminants are Known (Radioanalytical Scenario 3)
Description1
A public drinking water supply has been contaminated with a 90Sr source. Major portions of the
supply system have been isolated to prevent the spread of contamination into these portions of the
system. Unlike the two earlier scenarios, the radionuclide is known. For this reason, the screening
methods can be used with greater precision. For this scenario, the 1C has decided that the analytical
priority becomes low-activity samples because of a short-term need for reliable potable water
sources. Water samples are screened only for gross beta activity based on the MCL screening levels
for 90Sr. The laboratory has adjusted calibration2 of its screening survey equipment with 90Sr, making
the gross measurements more accurate. The efficiency with the open-end counter for 90Sr is 18% for
the sample geometry of a 1-L bottle. For this particular laboratory instrument, the 90Sr MCL of 8.0
pCi/L would yield a net (90Sr plus 90Y) beta screen value of (3.2 ± 0.4) cpm. (The uncertainty is for
illustrative purposes only.) Those samples having net beta activity below 3.2 cpm would be
suspected of being below the MCL for 90Sr concentration. The liquid scintillation instrument used
by this laboratory has an overall efficiency for 90Sr in aqueous samples of 86%, and a blank
background of (2.40 ± 0.06) cpm.
The laboratory also has calibrated its gamma survey meter with a 137Cs source yielding 0.017
pCi/cpm for the 1-L bottle. The radionuclide contaminants that initiated the incident should have
been completely characterized using the "Radioanalytical Scenario 1" process. The water supplies
sampled are likely to have radionuclide concentrations over the entire range previously seen from
this event. Although the primary focus is on potable water supplies, it is of secondary importance
to know where the activity is distributed in the water system. Thus, lower-priority samples (i.e., high
activity) will need to be reported to the 1C early on and will need to be analyzed eventually.
Event Sequence
It is Day 3 following the dispersal of a large amount of 90Sr into a drinking water supply. The source
of the water in the pipeline is from a reservoir that has been analyzed and found to be
uncontaminated. The intermediate phase of the event is ongoing. The Incident Command Center has
dispatched three samples from different segments of the water distribution system to determine if
these segments have already been contaminated.
The timing for results is as critical as in Radioanalytical Scenario 1 because the public water supply
has been shut down temporarily. Rebuilding public confidence in the cleanup effort will be
enhanced tremendously if portions of the system can be released for use. The three samples arrive
at the laboratory at 0800 hours on Day 3. It is assumed that 90Y is in full equilibrium with the 90Sr
when the samples arrive at the laboratory.
'Radionuclide Scenario 3 is unrelated to either Scenarios 1 or 2.
2The instrumentation was calibrated previously with a 137Cs source. The new calibration is with a 90Sr source. Because
90Sr will be in equilibrium with its 90Y progeny, the instrument also will measure the 90Y. Any 90Sr dispersed into the
water supply can be assumed to be in equilibrium with its progeny 90Y (72 hours has already passed since the onset of
the event), so the direct beta measurement will be a good approximation of the 90Sr concentration.
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Radiological Laboratory Sample Analysis Guide for Incidents of National Significance Radionuclides in Water
Analysis Path
Step 1. The three samples are surveyed upon arrival using a survey meter that has a sliding metal
window. The measurements for the three samples yield the following results for gross beta-gamma:
Sample Number
Instrument reading P + y, cpm
Instrument reading y only, cpm
L271
26 ±3
26 ±2
L375
35 ±3
26 ±2
L446
85 ±4
29 ±3
Background
28 ±3
25 ±2
(Associated uncertainties are 1 sigma.)
The direction from the 1C is to assess samples for potential as a source for drinking water. Since the
event-specific radionuclide is known (90Sr, Step 2P), the laboratory personnel use flowchart for
Scenario 3 to get directly to Step 3p. It is Day 3, 0830 hours.
Step spl. Sample L271 indicates that it is close to background and apparently has no significant
beta emitters based on the gross screen. A 10-mL aliquot is counted for 60 minutes using the LSC
yielding a value of 100 pCi/L. Using Table 12 in Appendix VI, an MDC for a 10-mL sample and
60 minute count time is 210 pCi/L (this would be adjusted by the laboratory to its specific counting
systems). The ADL for this measurement is 110 pCi/L.1 Because this result is less than the ADL,
its value is less than the MDC. Proceed to Step 4P1. It is Day 3, 1000 hours.
Both L375 and L446 yield significant beta and gamma count rates, and after Step 4 should be
considered for other analyses if directed by the 1C (Step 4p2).
Step 4(J1. 90Sr analysis is performed according to Standard Methods Procedure 7500-Sr (see
reference on page 9). The final analytical value determined for 90Sr is (1.95 ± 0.38) pCi/L, with an
MDC of 0.84 pCi/L. Because this is less than the MCL, proceed to Step 5pl.2 It is Day 4, 1400
hours.
Step 5pl. All other SDWA analyses are performed. The only other radionuclide identified is 226Ra
at a concentration of (2.6 ± 0.56) pCi/L, with an MDC of 0.90 pCi/L. It is Day 4, 2300 hours.
Step 6pl. The RDL value is 2.0 pCi/L for 90Sr and 1.0 pCi/L for 226Ra. Because 90Sr has an MDC
of 0.84 pCi/L, and 226Ra has an MDC of 0.90 pCi/L, MQO requirements for both radionuclides have
been met, and the data are deemed validated.
Step 7. The screening results were basically background. The low concentrations of the two
radionuclides found are consistent with the background reading on the gross scan, and on the gross
LSC analysis (the sum of the 90Sr and 226Ra would yield less than the gross counts background of
28 cpm for the survey meter, and the sum of the 90Sr and 226Ra progeny would yield less than the 100
pCi/L measured with the LSC gross screen).
'UBGR - LBGR = 210 - 0. um = 210/3.29 = 64. ADL = MDC - 1.645 x 64 = 105 cpm.
2However, additional analyses will need to be done to ensure that MCLs for all radionuclides are met before the water
supply is approved for consumption.
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Radiological Laboratory Sample Analysis Guide for Incidents of National Significance Radionuclides in Water
Step 8. The sum of the fractions does not need calculation unless tritium or other p and y emitters
are found in the sample. Ra-228 analysis will need to be done also to ensure compliance with the
SDWA. [If previous results from this water source are available, this step may be omitted.]
Step 9. The 1C is notified that water sample L271 has met the radionuclide requirements of the
SDWA. Gross screening of samples L375 and L446 indicated that they contained high levels of
radionuclides. Request direction as to whether or not detailed analyses on these sources should be
performed.
The time is Day 5, 2400 hours.
Elapsed time from receipt of samples at laboratory: 40 hours.
48
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Radiological Laboratory Sample Analysis Guide for Incidents of National Significance Radionuclides in Water
APPENDIX V. Representative Analytical Processing Times
Samples arrive at lab
Assess survey meter dose rate against
PAGs and field measurements
Perform rapid scan analyses for gross
activities of gamma, beta, and alpha
Sample preservation/preparation for
analysis or temporary storage
Prioritize samples for detailed
analysis for specific radionuclides
High activity
Low activity
Perform radionuclide-
specific analysis
I
Assign timeframe, specific analysis,
and refined priority for samples
Assess specific
results against
gross analysis
Discrepancy
Report positive
results, maintain
focus on high-
priority samples
Perform radionuclide-
specific analysis
Comparison with
acceptable results
Assess specific results
against gross analysis
Acceptable
Report acceptable
results
Report positive results,
Investigate source(s) of
discrepancy
Time (Hours)
0
0.25
1.0
1.25
1.5
High
3.0
3.5
Low
6.0
10-20
4.0 21 -24
(plus time for
discrepancies)
25-30
(plus time for
discrepancies)
Figure 5 - Approximate Timeframe for Radiochemical Analyses (Radioanalytical Scenario 1)
49
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Radiological Laboratory Sample Analysis Guide for Incidents of National Significance Radionuclides in Water
Samples arrive at lab
Survey containers for
3x instrument background.
Priority to samples with lowest
activity above background.
Gross a and p
"> 10x reagent blank:
Low priority
Gross a and p
: 10x reagent blank:'
High priority
f |
| Preserve j
I and archive j
.1.
Note: Analytical priority from here
on to samples < SDWA limits (MCLs).
Work deferred on other samples.
Gamma spectrometry
complete
Uranium analysis
complete
Tritium analysis
complete
Beta "hard-to-detects"
analyses complete
(e.g., Sr-90)
Alpha "hard-to-detects"
analyses complete
(e.g., Ra-226)
1
Check specific results against SDWA limits/MCLs
Check specific results against gross analyses
Report satisfactory water sources
Report unsatisfactory water sources
Timeline (Hours)
0.0
1.0
5.0
6.0
7.0
8.5
26
38
39
41
43
46
Figure 6 - Approximate Timeframe for Radiochemical Analyses (Radioanalytical Scenario 2)
50
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Radiological Laboratory Sample Analysis Guide for Incidents of National Significance Radionuclides in Water
Samples arrive at laboratory
Gross screen completed
Timeline (Hours)
0.0
0.5
Gamma spectrometry
analysis screen completed
Gross screen by
LSC or GPC completed
Gamma spectrometry
analysis for SDWA
requirements
Check AALs > SDWA
requirements
1.25
2.5
3.5
4.0
24-30
30-36
Figure 7 - Approximate Timeframe for Radiochemical Analyses (Radioanalytical Scenario 3)
51
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Radiological Laboratory Sample Analysis Guide for Incidents of National Significance Radionuclides in Water
APPENDIX VI. Establishing DQOs and MQOs for Incident Response Analysis
Three distinct radioanalytical scenarios are presented for water potentially contaminated with
radionuclides. The first two assume that the mixture of radionuclides in the sample is unknown. In
each scenario there is special emphasis on the implementation of the decision trees presented within
that scenario for prioritizing sample processing by the laboratory. This is to support timely decision-
making by the 1C regarding actions to protect human health for the first two cases, and in the third
case to expedite analysis so that suitable drinking water may be used. Specific MQOs are not given
for the third radioanalytical scenario because the analytical action levels (AALs) and decision levels
(DLs) default to the SDWA requirements (see Tables 7A and 7B). The screening analyses in this
scenario are simply used for internal laboratory prioritization.
This appendix covers single-sample screening measurement decisions by the laboratory. The 1C may
need to make decisions based on the final radionuclide-specific concentrations based on the mean
of the set of samples taken from an area. Measurement quality objectives (MQOs) would need to
be developed separately for this case. The required method uncertainty (WMR) should be smaller in
this case compared to the laboratory's screening decisions, perhaps by a factor of three (See
MARLAP Appendix C).
Is the
' parameter of
interest greater
than the
action level
7
The flowcharts depicted in this document contain decision points.
There are three basic symbols on these flowcharts: Squares, which
represent activities or tasks; diamonds, which represent decision
points; and arrows, which represent flow of control. In these flow
diagrams, there are many diamond-shaped decision points. Most
often they are of the form shown in Figure 8. This is the general
form of a theoretical decision rule as discussed in Step 5 of the data Figure 8 - A Decision Point in
quality objectives (DQO) process. The parameter of interest usually a Flowchart
is the "measurand" of the radiochemical analysis being performed
(e.g., concentration of a radionuclide, total activity, etc.). The AALs will have been set according
to criteria involving the appropriate PAGs or MCLs. The arrows specify the alternative actions to
be taken.
The DQO process1 may be applied to all programs involving the collection of environmental data
with objectives that cover decisionmaking activities. When the goal of the study is to support
decisionmaking, the DQO process applies systematic planning and statistical hypothesis testing
methodology to decide between alternatives. Data quality objectives can be developed using the
Guidance in EPA (2006) Guidance on Systematic Planning Using the Data Quality Objectives
Process (EPA QA/G-4). The DQO process is summarized in Figure 9.
Table 8 summarizes the DQO process. From these, MQOs can be established using the guidance in
MARLAP. The information in this table should be sufficient to enable the decisionmaker and
laboratory to determine the appropriate MQOs. The output should include an AAL, discrimination
limit, gray region, null hypothesis, analytical decision level (referred to in MARLAP as "critical
1 For appropriate samples, AALs and required detection limits are established in Safe Drinking Water Act regulations
(see box 13 in Scenario 1 and boxes 4c, 5, 6, 11, and 12b in Scenario 2).
52
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Radiological Laboratory Sample Analysis Guide for Incidents of National Significance Radionuclides in Water
level"), and required method uncertainty at the AAL. A table summarizing DQO process for each
decision point diamond can be prepared in advance and summarized as shown in Table 9.
Note that the existence of a decision point diamond implies that Steps 1-4 already have been
determined.
Step 1. State the Problem.
Define the problem that necessitates the study;
identify the planning team, examine budget, schedule.
Step 2. Identify the Goal of the Study.
State how environmental data will be used in meeting objectives and
solving the problem, identify study questions, define alternative outcomes.
Step 3. Identify Information Inputs.
Identify data and information needed to answer study questions.
Step 4. Define the Boundaries of the Study.
Specify the target population and characteristics of interest,
define spatial and temporal limits, scale of inference.
Step 5. Develop the Analytic Approach.
Define the parameter of interest, specify the type of inference,
and develop the logic for drawing conclusions from findings.
I ;
Decisionmaking
(hypothesis testing)
1
Estimation and other
analytic approaches
I
Step 6. Specify Performance or Acceptance Criteria.
Specify the probability limits for
false rejection and false
acceptance decision errors.
Develop performance criteria for new data
being collected or acceptable criteria for
existing data being considered for use.
Step 7. Develop the Plan for Obtaining Data.
Select the resource-effective sampling and analysis plan
that meets the performance criteria.
Figure redrawn from EPA G-4 (2006).
Figure 9 - The Data Quality Objectives Process
53
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Radiological Laboratory Sample Analysis Guide for Incidents of National Significance Radionuclides in Water
TABLE 8A - The DQO Process Applied to a Decision Point
STEP
Step 1 . Define the problem
Step 2. Identify the decision
Step 3 . Identify information
needed for the
decision
Step 4. Define the boundaries
of the study
Step 5. Develop a decision rule
This defines the decision point
diamond.
OUTPUT
. . . with a preliminary determination of the type of data needed and how
it will be used; identify decisionmaker.
...among alternative outcomes or actions, and a list of decision
statements that address the problem.
Analytical action levels that will resolve the decision and potential
sources for these; information on the number of variables that will need
to be collected; the type of information needed to meet performance or
acceptance criteria; information on the performance of appropriate
sampling and analysis methods.
Definition of the target population with detailed descriptions of
geographic limits (spatial boundaries); detailed descriptions of what
constitutes a sampling unittimeframe appropriate for collecting data and
making the decision or estimate, together with any practical constraints
that may interfere with data collection; and the appropriate scale for
decisionmaking or estimation.
Identification of the population parameters most relevant for making
inferences and conclusions on the target population; for decision
problems, the "if.., then. ..else..." theoretical decision rule based upon a
chosen AAL.
The theoretical decision rule specified in Step 5 can be transformed into statistical hypothesis tests
that are applied to the data. Due to the inherent uncertainty with measurement data, there is some
likelihood that the outcome of statistical hypothesis tests will lead to an erroneous conclusion, i.e.,
a decision error. This is illustrated in Table 8B.
TABLE 8B - Possible Decision Errors
Decision Made
Decide that the parameter of interest is
greater than the analytical action level
Decide that the parameter of interest is
less than the analytical action level
True Value of the parameter of interest
Greater than the AAL
Correct decision
Decision Error
Less than the AAL
Decision Error
Correct decision
In order to choose an appropriate null hypothesis (or baseline condition), consider which decision
error should be more protected against. Choose the null hypothesis which if falsely rejected would
cause the greatest harm. Then the data will need to be convincingly inconsistent with the null
hypothesis before it will be rejected, and the probability of this happening (a Type I error) is more
easily controlled during the statistical design. Using values from Table 8D, Figures 10 and 11
illustrate these concepts for case (a) and case (b) respectively.
Failing to detect a sample that exceeds the AAL could have consequences to public health. But
screening additional samples will slow the overall process and therefore also may impact the public
health. The probability that such decision errors occur are defined as the parameters a and P in steps
6.1 and 6.2 in Table 8C. Values of alpha and beta should be set based on the consequences of
making an incorrect decision. How these are balanced will depend on the AAL, sample loads, and
other factors as specified by the 1C.
54
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Radiological Laboratory Sample Analysis Guide for Incidents of National Significance Radionuclides in Water
The most commonly used values of alpha and beta are 5%, although this is by tradition and has no
sound technical basis. These values may be used as a default, but should be optimized in Step 7 of
the DQO process according to the actual risk of the decision error being considered.
TABLE 8C - The DQO Process Applied to a Decision Point
STEP
OUTPUT
Step 6. Specify limits on
decision errors
Step 6.1 Determine analyti-
cal action level (AAL) on
the gray region boundary
and set baseline condition
(null hypothesis, H0)
Which is considered the worse: decision error (a) deciding that the parameter of
interest is less than the AAL when it actually is greater, or (b) deciding that the
parameter of interest is greater than the AAL when it actually is less? Case (a)
is usually considered to be a conservative choice by regulatory authorities, but
this may not be appropriate in every case.
If (a), the AAL defines the upper boundary of the gray region. The null
hypothesis is that the sample concentration is above the AAL. (All samples will
be assumed to be above the AAL unless the data are convincingly lower.) A
desired limit will be set on the probability (a) of incorrectly deciding the sample
is below the AAL when the sample concentration is actually equal to the AAL.
If (b), the AAL defines the lower boundary of the gray region. The null
hypothesis is that the sample concentration is below the AAL. (All samples will
be assumed to be below the AAL unless the data are convincingly higher.) A
desired limit will be set on the probability (a) of incorrectly deciding the sample
is above the AAL when the sample concentration is actually equal to the AAL.
6.2 Define the discrimina-
tion limit (DL)
If (a), the discrimination limit defines the lower boundary of the gray region.[1]
It will be a concentration below the AAL where the desired limit will be set on
the probability (J3) of incorrectly deciding the sample is above the AAL.
If (b), the discrimination limit defines the upper boundary of the gray region.[2]
It will be a concentration above the AAL where the desired limit will be set on
the probability (fJ) of incorrectly deciding the sample is below the AAL.
6.3 Define the required
method uncertainty at the
AAL
According to MARLAP Appendix C, under either case (a) or case (b) above, the
recommended required method uncertainty is:
UBGR - LBGR A
u
'MR -
where zl_a and z^ are the \-a and I-/? quantiles of the standard normal
distribution function.
Step 1'. Optimize the design
for obtaining data
Iterate steps 1-6 to define optimal values for each of the parameters and the
measurement method required.
NOTES:
[1] The DL is the point where it is important to be able to distinguish expected signal from the AAL. When one expects
background activity, then it might be zero. If one expects activity near the AAL, however, it might be at 90% of the
AAL.
[2] The DL is the point where it is important to be able to distinguish expected signal from the AAL. If the AAL is near
zero, the DL would define a concentration deemed to be too high to be undetected. Thus, the DL may be set equal
to the MDC. If one expects activity near the AAL, however, it might be at 110% of the AAL.
55
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Radiological Laboratory Sample Analysis Guide for Incidents of National Significance Radionuclides in Water
»> SK
DC
II
.11
!^
as
Gray Region
Relatively Large
Decision Error Rat
are Considered
Tola-able
20 40 60 80 100 120 140 160 180 200
Action Level
True Value of the Parameter (Mean Concentration, ppm)
S
Jil
i
0.9 -
0.8
0.7 -
0.6-
0.5-
0.4 -
0.3-
0.2-
0.1 -
0
0
Tolerable False
Rejection Decision
Err. "
Tola-able Mse
Acceptance Decision
En-oi- Kates
Gray Region
Relatively Large
Decision EITOF Rates
are Considered
Tolerable
20 40 60
100 120 140 160 180 200
Action Level
True Value of the Parameter (Mean Concentration, ppm)
Figure 10 - Example Illustrating Case (a). Figure 11 - Example Illustrating Case (b).
Baseline Condition (null hypothesis): Parameter Baseline Condition (null hypothesis): Parameter
Exceeds the AAL Does Not Exceed the AAL
Figures taken from EPA G-4 (2006)
In Figure 10, the AAL = 100, the DL = 80, A = 100-80 = 20 a = J3=Q.l and
A 20
UMR s'
l-a
1.282 +1.282
= 7.8.
In Figure 11, the AAL = 100, the DL = 120, A = 120-100 = 20 a=J3=Q.l and
A 20
UMR s'
1.282 +1.282
= 7.8.
Table 8D - Values of Zt.a (or z^) for
Some Commonly Used Values of dr(or
a or P
0.001
0.01
0.025
0.05
0.10
0.20
0.30
0.50
Zj.a (or Zj.0)
3.090
2.326
1.960
1.645
1.282
0.842
0.524
0.000
The concentration that indicates the division between values leading to rej ecting the null hypothesis
and those that do not is termed the "critical level." Possible values of the concentration can be
divided into two regions, the acceptance region and the rejection region. If the value of the
concentration comes out to be in the acceptance region, the null hypothesis being tested is not
rejected. If the concentration falls in the rejection region, the null hypothesis is rejected. The set of
values of a statistic that will lead to the rejection of the null hypothesis tested is called the critical
region. Critical region is a synonym for rejection region.
56
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Radiological Laboratory Sample Analysis Guide for Incidents of National Significance Radionuclides in Water
In the context of analyte detection, the critical value (see MARLAP Attachment 3B.2) is the
minimum measured value (e.g., of the instrument signal or the analyte concentration) required to
give confidence that a positive (nonzero) amount of analyte is present in the material analyzed. The
critical value is sometimes called the critical level.
In case (a), the critical value will be UBGR - z,_a WM, where UM is its combined standard uncertainty
of the measurement result, x. Only measurement results less than the critical value will result in
rejecting the null hypothesis that the true concentration is greater than the AAL.
In case (b), the critical value will be LBGR + z1_a WM, where UM is its combined standard uncertainty
of the measurement result, x. Only measurement results greater than the critical value will result in
rejecting the null hypothesis that the true concentration is less than the AAL. This process can be
completed for each diamond in each flowchart to fill in Table 12. In these tables, all values have
been rounded to 2 significant figures.
In the following tables, MQOs were determined for screening using a discrimination level of zero
and Type I and Type II error rates of alpha = beta = 0.05. These are the MQOs usually associated
with developing MDCs and result in a relative method uncertainty of 3 0% at the AAL, and an ADL
value of 0.5 times the AAL.
For radionuclide specific measurements, the requirements are more stringent, using a discrimination
level of one-half the AAL and Type I and Type II error rates of alpha = 0.01 with beta = 0.05. This
results in a relative method uncertainty of 13% at the AAL and an ADL value of 0.71 times the
AAL. Note that gamma spectrometric measurements using an HPGe are always radionuclide
specific, and therefore, have the more stringent MQOs.
TABLE 9A - DQOs and MQOs for Radioanalytical Scenario 1. Prioritization Decisions Based on Screening'71
(Gross a, P, or y Measurements)
03
03
d
IU
03
, .
d
03
03
to
03
^
2,7
2,7
2,7
2,7
2,7
2,7
12
12
d
o
E
Q
-»-^
'o
Q_
d
O
to
03
Q
la
3,8
9
3,8
9
3,8
9
n[4]
13
13
15[5]
b
CO.
s
to"
to
CD
d
5
03
^>
1
y[l]
a
a
P
P
Y
Y
a
P
^!
o
i
CD
O
-^
<
58,000
2,000
400
12,000
2,400
33,000
6,600
15
50
3 "
o V to
nf L- g
'to J o
03 <, -^
-d
03
CD
P
03
03
^>
1
0.05
0.05
0.05
0.05
0.05
0.05
0.05
a
a
18,000
610P,3]
120[3]
3,600[3]
720pl
4,100[3]
830pl
a;
^2
S-
0.30
0.30
0.30
0.30
0.30
0.13
0.13
o
Q
1
Q
D:
58,000
3
5
03
03 -~~
' r^
« s
f:> '
03 03
Q S
"CD ^
j. CC
-^ -^
C /N
29,000
1,000
200
6,000
1200
23,000
4,600
15
50
|
3
o
03
^
O
03
500 mrem 137Cs
500 mrem 241Am
100 mrem24 'Am
500 mrem 90Sr
100 mrem 90Sr
500 mrem 60Co
100 mrem 60Co
SDWA
SDWA
Notes:
[1] Using survey instrument calibrated to 137Cs on contact in the recommended geometry.
57
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Radiological Laboratory Sample Analysis Guide for Incidents of National Significance Radionuclides in Water
[2] «
2000
MR ~
2000
1.645+1.645 3.29
610
[3] Diamond 9 is the limiting decision criterion.
[4] Mathematically computed from data obtained earlier.
[5] Based onprofessional judgment from data obtained earlier. The comparison made is based on the MQOs established
for the screening analyses and the individual radionuclide analyses. The acceptability of this measurement will vary
widely based on the actual radionuclides in the sample and the radionuclides used to calibrate the screening
instruments. Thus it will be incumbent on the laboratory staff to assess the agreement of these numbers. Guidance
given in the document is a ratio range of approximately 0.5 to 2.0.
[6] The value for #v (relative required method uncertainty) is determined by dividing the value of MMR by the AAL
(fourth column in this table).
[7] Values for gamma analysis assume radionuclide-specific analyses using an HPGe. If a gamma detector of lower
resolution is used, the screening error rates for gamma analysis should be changed to that of the alpha and beta
analysis.
TABLE 9B - DQOs and MQOs for Scenario 1. Values Reported Externally Based on Radionuclide-Specific
Measurements
03
O3
d
CD
1
d
03
to
CD
03
S
4
5
6
10
10
14
14
~o
d
o
CD
Q
d
n°
o
'to
o
03
Q
b
CO.
S
to"
ID
s
Q.
1
a
P
Y
a
PY
a
PY
G
^
I
CD
d
CD
O
T3
CO
O
CO
_03
-------
Radiological Laboratory Sample Analysis Guide for Incidents of National Significance Radionuclides in Water
TABLE 10A - Derived Water Concentrations (DWC) Corresponding to a-Emitting Radionuclide
Analytical Action Levels
Radionuclide
Gross a Screen [5]
Am-241
Cm-242
Cm-243
Cm-244
Np-237 [4]
Po-210
Pu-238
Pu-239
Pu-240
Ra-226 [4]
Th-228 [4]
Th-230
Th-232
U-234
U-235
U-238
Half-Life
-
432.2 y
162.8 d
29. ly
18.10y
2.144xl06y
138.4 d
87.7 y
2.411xl04y
6.564xl03y
1.600xl03y
1.912 y
7.538xl04y
1.405xl010y
2.455xl05y
7.038xl08y
4.468xl09v
Additional
Emissions
-
Y
Y
Y
yDP
yDP
yDP
yDP
yDP
vDP
pCi/L
500-mrem
AAL
[1] PI
2.0xl03
2.0xl03
1.4xl04
2.5xl03
2.9xl03
3.9xl03
130
1.8xl03
1.7xl03
1.7xl03
910
2.6xl03
1.8xl03
1.6xl03
6.3xl03
6.6xl03
7.0xl03
100-mrem
AAL
[1] PI P]
400
400
2.8xl03
500
580
780
26
360
340
340
180
520
360
320
1300
1300
1.4xl03
Notes:
The half-lives of the nuclides are given in years (y) or days (d). DP refers to "decay products."
[1] Values are based on the dose conversion factors in Federal Guidance Report No. 13, CD Supplement, 5-year-old
child and the 50th percentile of water consumption.
[2] 365-day intake.
[3 ] The-100 mrem AAL values were obtained by dividing 500-mrem PAG DWC values by 5. AALs have been rounded
to 2 significant figures.
[4] Includes decay products originating from the 226Ra or 228Th in the body. Used only to calculate the concentration
(pCi/L) or dose from 226Ra or 228Th in the body.
[5] The AAL and associated MMR and ADL values for241Am are used as the default for gross alpha screening analysis.
59
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Radiological Laboratory Sample Analysis Guide for Incidents of National Significance Radionuclides in Water
TABLE 10B - Derived Water Concentrations (DWC) Corresponding to P-Emitting Radionuclide AALs
Radionuclide
Beta Gamma
Screen [4]
Ac-227DP
Ce-141
Ce-144
Co-57
Co-60
Cs-134
Cs-137
H-3
1-125
1-129
1-131
IT- 192
Mo-99
P-32
Pd-103
Pu-241
Ra-228
Ru-103
Ru-106
Se-75
Sr-89
Sr-90
Tc-99
Emission Type
P
P (a DP)
PY
PY
Y
PY
PY
PY
weak P
Y
PY
PY
PY
P Y (Y DP)
P
Y
P
P (Y DP)
PY
PY
Y
P
P
PY
Half-Life
-
21.77 y
32.51 d
284.9 d
271. Id
5.270y
2.065 y
30.07 y
12.32 y
59.40 d
1.57xl07y
8.021 d
73.83d
65.94h
14.26 d
16.99 d
14.29 y
5.75y
39.26 d
373.6 d
119.8 d
50.53d
28.79 y
2.11xl05y
pCi/L
500-mrem
AAL
[1] PI
5.8xl04
l.lxlO3
2.2xl05
2.9xl04
6.3xl05
3.3xl04
4.3xl04
5.8xl04
7.7xl06
1.3xl04
3.3xl03
5.4xl03
1.2xl05
3.2xl05
5.9xl04
7.8xl05
l.OxlO5
160
2.3xl05
2.2xl04
6.7xl04
6.3xl04
1.2xl04
2.4xl05
100-mrem
AAL
[1] PI [3]
1.2xl04
220
4.4xl04
5.8xl03
1.3xl05
6.6xl03
8.6xl03
1.2xl04
1.5xl06
2.6xl03
660
l.lxlO3
2.4xl04
6.4xl04
1.2xl04
1.6xl05
2.0xl04
32
4.6xl04
4.4xl03
1.3xl04
1.3xl04
2.4xl03
4.8xl04
Notes:
The half-lives of the nuclides are given in years (y), days (d), or hours (h). DP refers to "decay products."
[1] Values are based on the dose conversion factors in Federal Guidance Report No. 13, CD Supplement, 5-year-old
child and the 50th percentile of water consumption.
[2] 365-day intake.
[3] The 100-mrem AAL values were obtained by dividing 500-mrem PAG DWC values by 5. AALs have been rounded
to 2 significant figures.
[4] The AAL and associated UMR and ADL values for 137Cs are used as the defaults for initial beta gamma screening
analysis on sample bottle (Step 1 in Radioanalytical Scenarios 1 and 2). The AAL and associated um and ADL
values for 60Co concentration are used as defaults for gross gamma measurements thereafter (see text). The AAL
and associated Mm and ADL values for 90Sr are the defaults used for gross beta screening.
Several nuclides in Table 10B decay by electron capture. These radionuclides cannot be detected
using gross P analysis. The electron capture decay leads to characteristic X-rays of the progeny
nuclide. The most effective way to detect the X-rays from these electron-capture-decay radionuc-
lides is either with a low-energy photon detector (LEPD) or a reverse electrode germanium detector
(N-type semiconductor detector). The lower range of energy with these detectors is about 10 keV.
60
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Radiological Laboratory Sample Analysis Guide for Incidents of National Significance Radionuclides in Water
TABLE 11A - DQOs and MQOs for Scenario 2.
Internal Lab Prioritization Decisions Based on Screening
(Gross a, ft, or y Measurements)
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61
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Radiological Laboratory Sample Analysis Guide for Incidents of National Significance Radionuclides in Water
counting times. The MDCs were calculated using the working expressions provided by Currie1, assuming
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Radiological Laboratory Sample Analysis Guide for Incidents of National Significance Radionuclides in Water
APPENDIX VII. Glossary
accuracy: The closeness of a measured result to the true value of the quantity being measured.
Various recognized authorities have given the word "accuracy" different technical definitions,
expressed in terms of bias and imprecision. Following MARLAP, this document avoids all of
these technical definitions and uses the term "accuracy" in its common, ordinary sense.
aerosol. A suspension of fine solid or liquid particles within a gaseous matrix (usually air).
aliquant: A representative portion of a homogeneous sample removed for the purpose of analysis
or other chemical treatment. The quantity removed is not an evenly divisible part of the whole
sample. An aliquot, by contrast, is an evenly divisible part of the whole.
analyte: See target analyte.
analytical action level (AAL): The value of a quantity that will cause the decisionmaker to choose
one of the alternative actions. The analytical action level may be a derived concentration level
(such as the derived water concentration in this document), background level, release criteria,
regulatory decision limit, etc. The AAL is often associated with the type of media, target
analyte, and concentration limit. Some AALs, such as the release criteria for license termination,
are expressed in terms of dose or risk. MARLAP uses the term "action level." See total effective
dose equivalent (TEDE).
analytical decision level (ADL). The minimum measured value for the radionuclide concentration
in a sample that indicates the amount of radionuclide present is equal to or greater than the
analytical action level at a specified Type II error rate (assumes that method uncertainty
requirements have been met). Any measurement result equal to or greater than the applicable
ADL is considered to have exceeded the corresponding analytical action level. MARLAP uses
the term "critical level."
background (instrument): Radiation detected by an instrument when no source is present. The
background radiation that is detected may come from radionuclides in the materials of construc-
tion of the detector, its housing, its electronics, and the building, as well as the environment and
natural radiation.
background level: A term that usually refers to the presence of radioactivity or radiation in the
environment. From an analytical perspective, the presence of background radioactivity in
samples needs to be considered when clarifying the radioanalytical aspects of the decision or
study question. Many radionuclides are present in measurable quantities in the environment.
bias (of a measurement process): A persistent deviation of the mean measured result from the true
or accepted reference value of the quantity being measured, which does not vary if a measure-
ment is repeated.
blank (analytical or method): Asample that is assumed to be essentially free of the target analyte
(the "unknown"), which is carried through the radiochemical preparation, analysis, mounting,
and measurement process in the same manner as a routine sample of a given matrix.
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Radiological Laboratory Sample Analysis Guide for Incidents of National Significance Radionuclides in Water
calibration: The set of operations that establishes, under specified conditions, the relationship
between values indicated by a measuring instrument or measuring system, or values represented
by a material measure, and the corresponding known value of a parameter of interest.
calibration source: A prepared source, made from a certified reference material, that is used for
calibrating instruments.
certified reference material: A radioactive material, accompanied by an uncertainty at a stated level
of confidence, with one or more values certified by a procedure that establishes its traceability
to accepted standard values. A "standard reference material" is a certified reference material
issued by the National Institute of Standards and Technology (NIST) in the United States. NIST
certifies a standard reference material for specific chemical or physical properties and issues it
with a certificate that reports the results of the characterization and indicates the intended use of
the material.
chain of custody: Procedures that provide the means to trace the possession and handling of a
sample from collection to data reporting.
check source: A material used to validate the operability of a radiation measurement device,
sometimes used for instrument quality control. See source, radioactive.
critical level. Termed analytical decision level in this document in the context of evaluating sample
results relative to an analytical action level. In the context of analyte detection, critical level
means the minimum measured value (e.g., of the instrument signal or the radionuclide concentra-
tion) that indicates a positive (nonzero) amount of a radionuclide is present in the material within
a specified probable error. The critical level is sometimes called the critical value or decision
level.
data quality objective (DQO) Qualitative and quantitative statements that clarify the study
objectives, define the most appropriate type of data to collect, determine the most appropriate
conditions from which to collect the data, and specify tolerable limits on decision error rates.
Because DQOs will be used to establish the quality and quantity of data needed to support
decisions, they should encompass the total uncertainty resulting from all data collection
activities, including analytical and sampling activities.
derived radionuclide concentration (DRC): General application term used in discussions involving
both of the terms derived air concentration and derived water concentration.
derived water concentration (DWC). The concentration of a radionuclide, in pCi/L, that would
result in exposure to a specified dose level. Generally refers to ^protective action guide or other
specified dose- or risk-based factor related to an analytical action level. In this document, for
example, the "500-mrem DWC for 239Pu" is the concentration of 239Pu, in pCi/L, that would
result in an exposure of 500 mrem and would refer to the 500-mrem PAG. The DWC is
radionuclide-specific.
discrimination limit (DL). The DL is the point where it is important to be able to distinguish
expected signal from the analytical action level. The boundaries of the gray region.
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Radiological Laboratory Sample Analysis Guide for Incidents of National Significance Radionuclides in Water
dose equivalent. Quantity that expresses all radiations on a common scale for calculating the
effective absorbed dose. This quantity is the product of absorbed dose (grays (Gy) or rads)
multiplied by a quality factor and any other modifying factors (MARSSIM, 2000). The quality
factor adjusts the absorbed dose because not all types of ionizing radiation create the same effect
on human tissue. For example, a dose equivalent of one sievert (Sv) requires 1 Gy of beta or
gamma radiation, but only 0.05 Gy of alpha radiation or 0.1 Gy of neutron radiation. Because
the sievert is a large unit, radiation doses often are expressed in millisieverts (mSv). See total
effective dose equivalent and roentgen.
gray (Gy): The International System of Units (SI) unit for absorbed radiation dose. One gray is 1
joule of energy absorbed per kilogram of matter, equal to 100 rad. See sievert.
gray region: The range of possible values in which the consequences of decision errors are
relatively minor. Specifying a gray region is necessary because variability in the analyte in a
population and imprecision in the measurement system combine to produce variability in the
data such that the decision may be "too close to call" when the true value is very near the
analytical action level. The gray region establishes the minimum distance from the analytical
action level where it is most important to control Type II decision errors.
incident of national significance (INS): An actual or potential high-impact event that requires a
coordinated and effective response by and appropriate combination of federal, state, local, tribal,
nongovernmental, or private-sector entities in order to save lives and minimize damage, and
provide the basis for long-term community recovery and mitigation activities.
measurement quality objective (MQO): The analytical data requirements of the data quality
objectives, which 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. MARLAP refers to these performance objectives as MQOs. Examples of
quantitative MQOs include statements of required analyte detectability and the uncertainty of
the analytical protocol at a specified radionuclide concentration, such as the analytical action
level. Examples of qualitative MQOs include statements of the required specificity of the
analytical protocol (e.g., the ability to analyze for the radionuclide of interest (or target analyte}
given the presence of interferences).
method uncertainty: The predicted uncertainty of the result that would be measured if the method
were applied to a hypothetical laboratory sample with a specified analyte concentration.
Although individual measurement uncertainties will vary from one measured result to another,
the required method uncertainty is a target value for the individual measurement uncertainties
and is an estimate of uncertainty before the sample is actually measured. See also uncertainty,
required method uncertainty, and relative required method uncertainty.
method validation: The demonstration that the method selected for the analysis of a particular
analyte in a given matrix is capable of providing analytical results to meet the proj ect' s measure-
ment quality objectives and any other requirements in the analytical protocol specifications.
minimum detectable concentration (MDC): An estimate of the smallest true value of the analyte
concentration that gives a specified high probability of detection.
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Radiological Laboratory Sample Analysis Guide for Incidents of National Significance Radionuclides in Water
nuclide-specific analysis: Radiochemical analysis performed to isolate and measure a specific
radionuclide.
null hypothesis (H^: One of two mutually exclusive statements tested in a statistical hypothesis test
(compare with alternative hypothesis). The null hypothesis is presumed to be true unless the test
provides sufficient evidence to the contrary, in which case the null hypothesis is rejected and the
alternative hypothesis (Hj) is accepted.
performance evaluation (PE) program: A laboratory's participation in an internal or external
program of analyzing proficiency-testing samples appropriate for the analytes and matrices under
consideration (i.e.,PE program traceable to a national standards body, suchasNIST). Reference-
material samples used to evaluate the performance of the laboratory are called performance-
evaluation or proficiency-testing samples or materials. See certified reference material.
precision: The closeness of agreement between independent test results obtained by applying the
experimental procedure under stipulated conditions. Precision may be expressed as the standard
deviation. Conversely, imprecision is the variation of the results in a set of replicate measure-
ments.
protective action guide (PAG). The radiation dose to individuals in the general population that
warrants protective action following a radiological event. In this document, PAGs limit the
projected radiation doses for different exposure periods: not to exceed 2-rem total effective dose
equivalent (TEDE) during the first year, 500-mrem TEDE during the second year, or 5 rem over
the next 50 years (including the first and second years of the incident). See total derived water
concentration and analytical action level.
quality assurance (QA): An integrated system of management activities involving planning,
implementation, assessment, reporting, and quality improvement to ensure that a process, item,
or service is of the type and quality needed and expected. Quality assurance includes quality
control.
quality control (QC): The overall system of technical activities that measures the attributes and
performance of a process, item, or service against defined standards to verify that they meet the
stated requirements established by the proj ect; operational techniques and activities that are used
to fulfill requirements for quality. This system of activities and checks is used to ensure that
measurement systems are maintained within prescribed limits, providing protection against out-
of-control conditions and ensuring that the results are of acceptable quality.
reference material. See certified reference material.
rem: The common unit for the effective or equivalent dose of radiation received by a living
organism, equal to the actual dose (in rads) multiplied by a factor representing the danger of the
radiation. Rem is an abbreviation for "roentgen equivalent man," meaning that it measures the
biological effects of ionizing radiation in humans. One rem is equal to 0.01 Sv. See sievert and
dose equivalent.
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Radiological Laboratory Sample Analysis Guide for Incidents of National Significance Radionuclides in Water
relative required method uncertainty (ffMK): The required method uncertainty divided by the
analytical action level. The relative required method uncertainty is applied to radionuclide
concentrations above the analytical action level. A key measurement quality objective.
required method uncertainty («MR): Method uncertainty at a specified concentration. A key
measurement quality objective. See also relative required method uncertainty .
roentgen (R). A unit of exposure to ionizing radiation. It is that amount of gamma rays or X-rays
required to produce ions carrying one electrostatic unit of electrical charge in one cubic
centimeter of dry air under standard conditions. The unit of exposure rate is roentgens per hour
(R/h). For environmental exposures, the typical units are microroentgens per hour (|j,R/h), or 1 (T6
R/h. In SI units, 1 R = 2.58x10^ C/kg (coulombs per kilogram).
sample: (1) A portion of material selected from a larger quantity of material. (2) A set of individual
samples or measurements drawn from a population whose properties are studied to gain informa-
tion about the entire population.
screening method: An economical gross measurement (alpha, beta, gamma) used in a tiered
approach to method selection that can be applied to analyte concentrations below an analyte
level in the analytical protocol specifications or below a fraction of the specified action level.
sievert (Sv): The SI unit for the effective dose of radiation received by a living organism. It is the
actual dose received (grays in SI or rads in traditional units) times a factor that is larger for more
dangerous forms of radiation. One Sv is 100 rem. Radiation doses are often measured in mSv.
An effective dose of 1 Sv requires 1 gray of beta or gamma radiation, but only 0.05 Gy of alpha
radiation or 0.1 Gy of neutron radiation.
source, radioactive: A quantity of material configured for radiation measurement.
source term radionuclide: A radionuclide that is a significant contaminant in an environmental
sample and results in dose contributions that will be important in decisionmaking.
sum of fractions. A calculated value to determine whether the summed contributions to dose by all
radionuclides in a sample, divided by their respective dose limits, exceeds 1.0. For purposes of
this calculation, the actual analytical action level (derived water concentration or protective
action guide) is used rather than an analytical decision level.
swipes: A filter pad used to determine the level of general radioactive contamination when it is
wiped over a specific area, about 100 cm2 in area. Also called smears or wipes.
target analyte: A radionuclide on the list of radionuclides of interest or a radionuclide of concern
for a project.
total effective dose equivalent: The sum of the effective dose equivalent (for external exposure) and
the committed effective dose equivalent (for internal exposure), expressed in units of Sv or rem.
See dose equivalent.
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Radiological Laboratory Sample Analysis Guide for Incidents of National Significance Radionuclides in Water
Type I decision error: In a hypothesis test, the error made by rejecting the null hypothesis when it
is true. A Type I decision error is sometimes called a "false rejection" or a "false positive."
Type IIdecision error: In a hypothesis test, the error made by failing to reject the null hypothesis
when it is false. A Type II decision error is sometimes called a "false acceptance" or a "false
negative."
uncertainty: A parameter, associated with the result of a measurement, that characterizes the
dispersion of the values that could reasonably be attributed to the measurand. See method
uncertainty.
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