&EPA
EPA 600/R-11/081 | August 2011 iwww.epa.gov/ord
United States
Environmental Protection
Agency
Technology Evaluation Report
Argonne National Laboratory
Argonne SuperGel for
Radiological Decontamination
Office of Research and Development
National Homeland Security Research Center

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EPA 600-R-11-081
August 2011
Technology Evaluation Report
Argonne National Laboratory
Argonne SuperGel for Radiological
Decontamination

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Disclaimer
The U.S. Environmental Protection Agency (EPA), through its Office of Research and
Development's National Homeland Security Research Center, funded and managed this
technology evaluation through a Blanket Purchase Agreement under General Services
Administration contract number GS23F0011L-3 with Battelle. This report has been peer
and administratively reviewed and has been approved for publication as an EPA
document. Mention of trade names or commercial products does not constitute
endorsement or recommendation for use of a specific product.
Questions concerning this document or its application should be addressed to:
John Drake
National Homeland Security Research Center
Office of Research and Development
U.S. Environmental Protection Agency
26 West Martin Luther King Dr.
Cincinnati, OH 45268
513-569-7164
drake.john@epa.gov

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Foreword
The Environmental Protection Agency (EPA) holds responsibilities associated with
homeland security events: EPA is the primary federal agency responsible for
decontamination following a chemical, biological, and/or radiological (CBR) attack. The
National Homeland Security Research Center (NHSRC) was established to conduct
research and deliver scientific products that improve the capability of the Agency to carry
out these responsibilities.
An important goal of NHSRC's research is to develop and deliver information on
decontamination methods and technologies to clean up CBR contamination. When
directing such a recovery operation, EPA and other stakeholders must identify and
implement decontamination technologies that are appropriate for the given situation. The
NHSRC has created the Technology Testing and Evaluation Program (TTEP) in an effort
to provide reliable information regarding the performance of homeland security related
technologies. Through TTEP, NHSRC provides independent, quality assured
performance information that is useful to decision makers in purchasing or applying the
tested technologies. TTEP provides potential users with unbiased, third-party information
that can supplement vendor-provided information. Stakeholder involvement ensures that
user needs and perspectives are incorporated into the test design so that useful
performance information is produced for each of the tested technologies. The technology
categories of interest include detection and monitoring, water treatment, air purification,
decontamination, and computer modeling tools for use by those responsible for protecting
buildings, drinking water supplies and infrastructure, and for decontaminating structures
and the outdoor environment. Additionally, environmental persistence information is also
important for containment and decontamination decisions.
NHSRC is pleased to make this publication available to assist the response community to
prepare for and recover from disasters involving CBR contamination. This research is
intended to move EPA one step closer to achieving its homeland security goals and its
overall mission of protecting human health and the environment while providing
sustainable solutions to our environmental problems.
Jonathan G. Herrmann, Director
National Homeland Security Research Center
111

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Acknowledgments
Contributions of the following individuals and organizations to the development of this document
are gratefully acknowledged.
United States Environmental Protection Agency (EPA)
John Drake
Emily Snyder
Eletha Brady-Roberts
Nicholas Brescia
Jim Mitchell
University of Tennessee
Dr. Howard Hall
United States Department of Energy's Idaho National Laboratories
Battelle Memorial Institute
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Contents
Disclaimer	ii
Foreword	iii
Acknowledgments	iv
Abbreviations/Acronyms	vii
Executive Summary	viii
1.0 Introduction	1
2.0 Technology Description	3
3.0 Experimental Details	5
3.1	Experiment Preparation	4
3.1.1	Concrete Coupons	4
3.1.2	Coupon Contamination	4
3.1.3	Measurement of Activity on Coupon Surface	5
3.1.4	Surface Construction Using Test Stand	6
3.2	Evaluation Procedures	6
4.0 Quality Assurance/Quality Control	8
4.1	Intrinsic Germanium Detector	8
4.2	Audits	9
4.2.1	Performance Evaluation Audit	9
4.2.2	Technical Systems Audit	10
4.2.3	Data Quality Audit	10
4.3	QA/QC Reporting	10
5.0 Evaluation Results	11
5.1	Decontamination Efficacy	11
5.2	Deployment and Operational Factors	12
6.0 Performance Summary	15
6.1	Decontamination Efficacy	15
6.2	Deployment and Operational Factors	15
7.0 References	16
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Figures
Figure 3-1. Demonstration of contaminant application technique	5
Figure 3-2. Containment tent: outer view (left) and inner view with test stand
containing contaminated coupons (right)	6
Figure 5-1. ASG in container prior to application (top left), after application to concrete
coupon (bottom left), and during vacuum removal (right)	13
Tables
Table 3-1. Characteristics of Portland Cement Clinker Used to Make Concrete
Coupons	4
Table 4-1. Calibration Results - Difference from Th-228 Calibration Energies	8
Table 4-2. NIST-Traceable Eu-152 Activity Standard Check	10
Table 5-1. Decontamination Efficacy Results for Argonne SuperGel	12
Table 5-2. Operational Factors Gathered from the Evaluation	14
vi

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Abbreviations/Acronyms
ANSI
American National Standards Institute
ANL
Argonne National Laboratory
ASG
Argonne SuperGel
ASTM
ASTM International
BQ
Becquerel
°C
degrees Celsius
CBRNIAC
Chemical, Biological, Radiological and Nuclear Defense Information Analysis

Center
CC
cross-contamination
Cs
cesium
cm
centimeter
cm2
square centimeter
DARPA
Defense Advanced Research Projects Agency
DF
decontamination factor
DHS
U.S. Department of Homeland Security
DOD
Department of Defense
EPA
U.S. Environmental Protection Agency
Eu
Europium
°F
degrees Fahrenheit
hr
hour
IEEE
Institute of Electrical and Electronics Engineers
INL
Idaho National Laboratory
keV
kilo electron volts
mL
milliliter(s)
L
liter
m
meter
m2
square meter
jj.Ci
microCurie
NHSRC
National Homeland Security Research Center
NIST
National Institute of Standards and Technology
ORD
Office of Research and Development
PE
performance evaluation
PPE
personal protective equipment
%R
percent removal
QA
quality assurance
QC
quality control
QMP
quality management plan
RDD
radiological dispersion device
RH
relative humidity
RML
Radiological Measurement Laboratory
RSD
relative standard deviation
Th
thorium
TSA
technical systems audit
TTEP
Technology Testing and Evaluation Program

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Executive Summary
The U.S. Environmental Protection Agency's (EPA) National Homeland Security
Research Center (NHSRC) is helping to protect human health and the environment from
adverse impacts resulting from acts of terror by carrying out performance tests on
homeland security technologies. Through the Technology Testing and Evaluation
Program (TTEP), NHSRC evaluated the Argonne National Laboratory (ANL) SuperGel
(hereafter referred to as ASG) and its ability to remove radioactive cesium (Cs)-137 from
the surface of unpainted concrete.
Experimental Procedures. The ASG is a system of superabsorbing polymers containing
solid sequestering agents dissolved in a nonhazardous ionic wash solution. The resulting
hydrogel is applied to a contaminated surface and provides exchangeable ions to the
substrate to promote the desorption of radioactive cesium and other radionuclides. Eight
15 centimeter (cm) x 15 cm unpainted concrete coupons were contaminated with
approximately 1 microCurie (|iCi) of Cs-137 per coupon. The amount of contamination
deposited on each coupon was measured using gamma spectroscopy. The eight
contaminated coupons were placed in a test stand (along with one uncontaminated blank
coupon) that was designed to hold nine concrete coupons in a vertical orientation to
simulate the wall of a building. Each coupon was decontaminated with ASG and the
decontamination efficacy was determined by calculating both a decontamination factor
(DF) and percent removal (%R). Important deployment and operational factors were also
documented and reported.
Results. The decontamination efficacy (in terms of %R) attained for decontamination
with ASG was evaluated for each concrete coupon used during the evaluation. When the
decontamination efficacy metrics (%R and DF) of the eight contaminated coupons were
averaged together, the average %R for the ASG was 71% ± 4% and the average DF was
3.6 + 0.62.
The ASG had to be prepared from two powders combined with water. When fully
mixed, the mixture had the look of cooked oatmeal, but was very "slippery" as it tended
to slide off tools that were used to get the ASG onto the concrete coupons. The ASG was
applied to the concrete coupons using a paint brush to transport the ASG and a spackling
knife to smooth the ASG across the surface. After a 90 minute dwell time, a wet vacuum
was used to remove the ASG. Use of the ASG was very straight forward. Minimal
training would be required for technicians using the ASG, and the surface of the concrete
was not visibly damaged during decontamination with the ASG.

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1.0 Introduction
The U.S. Environmental Protection
Agency's (EPA) National Homeland
Security Research Center (NHSRC) is
helping to protect human health and the
environment from adverse effects
resulting from acts of terror. NHSRC is
emphasizing decontamination and
consequence management, water
infrastructure protection, and threat and
consequence assessment. In doing so,
NHRSC is working to develop tools and
information that will improve the ability
of operational personnel to detect the
intentional introduction of chemical,
biological, or radiological contaminants
on or into buildings or water systems, to
contain or mitigate these contaminants,
to decontaminate affected buildings
and/or water systems, and to dispose of
contaminated materials resulting from
cleanups.
NHSRC's Technology Testing and
Evaluation Program (TTEP) works in
partnership with recognized testing
organizations; stakeholder groups
consisting of buyers, vendor
organizations, and permitters; and
through the participation of individual
technology developers in carrying out
performance tests on homeland security
technologies. The program evaluates the
performance of homeland security
technologies by developing evaluation
plans that are responsive to the needs of
stakeholders, conducting tests, collecting
and analyzing data, and preparing peer-
reviewed reports. All evaluations are
conducted in accordance with rigorous
quality assurance (QA) protocols to
ensure that data of known and high
quality are generated and that the results
are defensible. Through TTEP, NHSRC
provides high-quality information that is
useful to decision makers in purchasing
or applying the evaluated technologies,
and in planning cleanup operations. The
evaluations generated through TTEP
provide potential users with unbiased,
third-party information that can
supplement vendor-provided
information. Stakeholder involvement
ensures that user needs and perspectives
are incorporated into the evaluation
design so that useful performance
information is produced for each of the
evaluated technologies.
Through TTEP, NHSRC evaluated the
performance of Argonne SuperGel
(hereafter referred to as ASG) from
Argonne National Laboratory (Argonne,
IL), in removing radioactive isotope
cesium (Cs)-137 from unpainted
concrete. A peer-reviewed test/QA plan
was followed, entitled, "The
Performance of Selected Radiological
Decontamination Processes on Urban
Substrates", Version 1.0, Amendment 1
dated July 14, 2010. This document will
be referred to as the test/QA plan and
was developed according to the
requirements of the Quality Management
Plan (QMP) for the Technology Testing
and Evaluation Program, Version 3.0
dated January 2008. The evaluation
generated the following performance
information:
• Decontamination efficacy,
defined as the extent of
radionuclide removal following
use of the ASG, and the
possibility of cross-
contamination (CC)
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• Deployment and operational
factors, including the
approximate rate of surface area
decontamination, applicability to
irregular surfaces, skilled labor
requirement, utility requirements,
portability, secondary waste
management, and technology
cost.
The evaluation of the ASG took place
November 2, 2010, with the pre-
evaluation activity measurements
occurring in September 2010 and the
post-evaluation activity measurements
also occurring in November 2010. All
of the experimental work took place in a
radiological contamination area at the
U.S. Department of Energy's Idaho
National Laboratory (INL). This report
describes the quantitative results and
qualitative observations gathered during
the evaluation of the ASG. The
contractor and EPA were responsible for
QA oversight. A technical systems audit
(TSA) was conducted during the
evaluation as well as a data quality audit
of the evaluation data.
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2.0 Technc
This technology evaluation report
provides results on the performance of
ASG under laboratory conditions. The
following description of the ASG is
based on information provided by the
vendor and was not verified during this
evaluation.
The ASG is a system of super absorbing
polymers containing solid sequestering
agents dissolved in a nonhazardous ionic
wash solution. The resulting hydrogel is
applied to a contaminated surface and
provides exchangeable ions to the
substrate to promote the desorption of
radioactive cesium and other
radionuclides. The solid sequestering
agent provides strong sorption of the
target radionuclides within the gel.
After removing the radionuclide-loaded
hydrogel by conventional wet-vacuum,
the hydrogel can be dehydrated or
incinerated to minimize waste volume
without loss of volatilized contaminants.
To summarize, the goals of this
approach are:
In situ dissolution of bound
contaminants without dissolving or
corroding contaminated structural
components.
Controlled extraction of water and
dissolved radionuclides from the
surface and pore/microcrack
structures into a super-absorbing
hydrogel.
Rapid stabilization of the
solubilized radionuclides with high-
affinity and high-specificity
sequestering agents immobilized in
the hydrogel layer.
Low toxicity reagents and low
volume radioactive waste.
The superabsorbing polymers consist of
an anionic mixture of polyacrylamide
and polyacrylate in both linear and
cross-linked form. The solid
sequestering agent is mixed into the dry
polymer (10% by mass). The ionic wash
solution is composed of a single
component salt at 1 mole/liter (L)
concentration (no strong acid or base is
used). The reconstituted hydrogel (19-20
gram ionic wash solution per gram of
dry polymer mix) is applied by hand for
small applications or sprayed on for
larger applications. The hydrogel is
allowed to react with the contaminated
surface for at least 30-60 minutes to
maximize the ionic exchange of
radionuclides and diffusion/absorption
into the hydrogel. The hydrogel is
designed to adhere to vertical surfaces
without slipping and maintain hydration
in direct sunlight for more than an hour.
Because no component of the hydrogel
is hazardous, there are no special
precautions required to deal with
hazardous materials. The hydrogel is
also compliant with disposal as low-
level radioactive waste.
Conventional wet-vacuum technology is
sufficient to remove the hydrogel from
the contaminated surface. For small-
scale applications, the head of a standard
wet vacuum is adequate, while for larger
scale applications, a squeegee
attachment is recommended.
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3.0 Experimental Details
3.1 Experiment Preparation
3.1.1 Concrete Coupons
The concrete coupons were prepared
from a single batch of concrete made
from Type II Portland cement. The
ready-mix company (Burns Brothers
Redi-Mix, Idaho Falls, ID) that supplied
the concrete for this evaluation provided
the data which describe the cement
clinker used in the concrete mix. For
Type II Portland cement, the ASTM
International (ASTM) Standard C 150-71
specifies that tricalcium aluminate
accounts for less than 8% of the overall
cement clinker (by weight). The cement
clinker used for the concrete coupons
was 4.5% tricalcium aluminate (Table 3-
1). For Type I Portland cement the
tricalcium aluminate content should be
less than 15%. Because Type I and II
Portland cements differ only in
tricalcium aluminate content, the cement
used during this evaluation meets the
specifications for both Type I and II
Portland cements. The apparent porosity
of the concrete from the prepared
coupons ranged from 15-30%).
Table 3-1. Characteristics of Portland Cement Clinker
	Used to Make Concrete Coupons	
Cement Constituent	Percent of Mixture
Tricalcium Silicate	57.6
Dicalcium Silicate	21.1
Tricalcium Aluminate	4.5
Tetracalcium Aluminoferrite	8.7
Minor Constituents	8.1
The concrete was representative of
exterior concrete commonly found in
urban environments in the United States
as shown by INL under a previous
project entitled, "Radionuclide Detection
and Decontamination Program. Broad
Agency Announcement 03-013"
sponsored by the U.S. Department of
Defense (DOD), Defense Advanced
Research Projects Agency (DARPA) and
U.S. Department of Homeland Security
(DHS). The wet concrete was poured
into 0.9 meter (m) square plywood forms
with the exposed surface "floated" to
allow the smaller aggregate and cement
paste to float to the top, and the concrete
was then cured for 21 days. Following
curing, the squares were cut to the
desired size with a laser-guided rock
saw. For this evaluation, the "floated"
surface of the concrete coupons was
used. The coupons were approximately 4
centimeters (cm) thick, 15 cm x 15 cm
square, and had a surface finish that was
consistent across all the coupons.
3.1.2 Coupon Contamination
Eight coupons were contaminated by
spiking individually with 2.5 milliliters
(mL) of aqueous solution that contained
0.4 microCurie (|iCi)/mL Cs-137 as a
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solution of cesium chloride, which
corresponded to an activity level of
approximately 1 jaCi over the 225 square
centimeters (cm') surface. Application
of the Cs-137 in an aqueous solution was
justified because even if Cs-137 were
dispersed in a particle form following a
radiological dispersion device (RDD) or
"dirty bomb" event, morning dew or
rainfall would likely occur before the
surfaces could be decontaminated. In
addition, from an experimental
standpoint, it is much easier to apply
liquids, rather than particles,
homogeneously across the surface of the
concrete coupons. The liquid spike was
delivered to each coupon using an
aerosolization technique developed by
INL (under a DARPA/DHS project).
The aerosol delivery device was
constructed of two syringes. The plunger
and needle were removed from the first
syringe and discarded. Then a
compressed air line was attached to the
rear of the syringe. The second syringe
nt solution is effectively distributed
across the surface of the coupon.
contained the contaminant solution and
was equipped with a 27 gauge needle,
which penetrated through the plastic
housing near the tip of the first syringe.
Compressed air flowing at a rate of
approximately 1 - 2 L per minute created
a turbulent flow through the first
syringe. When the contaminant solution
in the second syringe was introduced,
the contaminant solution became
nebulized by the turbulent air flow. A
fine aerosol was ejected from the tip of
the first syringe, creating a controlled
and uniform spray of fine liquid droplets
onto the coupon surface. The
contaminant spray was applied all the
way to the edges of the coupon, which
were taped (after having previously been
sealed with polyester resin) to ensure
that the contaminant was applied only to
the surfaces of the coupons. The
photographs in Figure 3-1 show this
procedure being performed using a
nonradioactive, nonhazardous aqueous
dye to demonstrate that the 2.5 mL of
contamina
Figure 3-1. Demonstration of contaminant application technique
3.1.3 Measurement of Activity on
Coupon Surface
Gamma radiation from the surface of
each concrete coupon was measured to
quantify contamination levels both
before and after evaluation of the ASG.
These measurements were made using
an intrinsic high purity germanium
detector (Canberra LEGe Model GL
2825R/S, Meriden, CT). After being
placed in the detector, each coupon was
measured until the average activity level
of Cs-137 from the surface stabilized to
a relative standard deviation (RSD) of
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less than 2%. Gamma-ray spectra
acquired from Cs-137 contaminated
coupons were analyzed using INL
Radiological Measurement Laboratory
(RML) data acquisition and spectral
analysis programs. Radionuclide
activities on coupons were calculated
based on efficiency, emission
probability, and half-life values. Decay
corrections were made based on the date
and the duration of the counting period.
Full RML gamma counting QA/quality
control (QC), as described in the test/QA
plan, was employed and certified results
were provided.
3.1.4 Surface Construction Using Test
Stand
To evaluate the decontamination
technologies on vertical surfaces
(simulating walls), a stainless steel test
stand that held three rows of three
concrete coupons was used. The test
stand, approximately 2.7 m x 2.7 m, was
erected within a containment tent. The
concrete coupons were placed into
holders so their surfaces extended just
beyond the surface of the stainless steel
face of the test stand. Eight of the nine
coupons placed in the test stand were
contaminated with Cs-137, which has a
half-life of 30 years. One
uncontaminated coupon was placed in
the bottom row of the test stand (position
8) and decontaminated in the same way
as the other coupons. This coupon,
referred to as the CC blank, was placed
there to observe possible CC caused by
the decontamination higher on the wall.
Figure 3-2 shows the containment tent
and the test stand loaded with the
concrete coupons.
Figure 3-2. Containment tent: outer view (left) and inner view with test stand
containing contaminated coupons with numbered coupon positions (right).
3.2 Evaluation Procedures
The eight concrete coupons in the test
stand which had been contaminated
approximately one month before were
decontaminated using the ASG. The
ASG was applied from top to bottom to
simulate an approach that would likely
be taken in an actual decontamination
event, where higher wall surfaces would
be decontaminated first because of the
possibility of secondary contamination
lower on the wall.
The ASG was prepared by mixing two
dry powders with water as directed by
the vendor. The mixture was then stirred
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with a drill equipped with a mixing tool
until the mixture was homogeneous.
The ASG was applied to the concrete
coupons using a four-inch paint brush to
transport the ASG and a spackling knife
to smooth the ASG across the surface.
The specifications of the paint brush
were not critical as a perfectly smooth
application was not required.
Altogether, the application of the ASG
took approximately 45 seconds per
coupon, the ASG was allowed to be on
the surface for 90 minutes, and then the
ASG was removed with a wet vacuum
(12 gallon, 4.5 horsepower, QSP® Quiet
Deluxe, Shop-Vac Corporation,
Williamsport, VA) which required
approximately one minute per concrete
coupon. The temperature and relative
humidity (RH) were recorded at the start
and finish. The temperature and RH
were 21°C (70 °F) and 22% at the start
and 22°C (72 °F) and 22% at the finish.
According to the vendor, these
conditions were acceptable for use of the
ASG.
The overall decontamination method for
the ASG included:
1.	Apply gel with paint brush and
smoothing with spackling knife
2.	Wait 90 minutes
3.	Remove with wet vacuum by
moving over the surface one time
with a 4 inch flat vacuum
attachment against the surface.
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4.0 Quality Assurance/Quality Control
QA/QC procedures were performed in
accordance with the program QMP and
the test/QA plan for this evaluation.
4.1 Intrinsic Germanium Detector
The germanium detector was calibrated
weekly during the overall project. The
calibration was performed in accordance
with standardized procedures from the
American National Standards Institute
(ANSI) and the Institute of Electrical
and Electronics Engineers (IEEE).3 In
brief, detector energy was calibrated
using thorium (Th)-228 daughter gamma
rays at 238.6, 583.2, 860.6, 1620.7, and
2614.5 kilo electron volts (keV). Table
4-1 shows the calibration results across
the duration of the project. Each row
gives the difference between the known
energy levels and those measured
following calibration (rolling average
across the six most recent calibrations).
Pre-contamination measurements were
performed in late September and the
post-contamination results were
measured in late November. Each row
represents a six week rolling average of
calibration results. In addition, the
energies were compared to the previous
30 calibrations to confirm that the results
were within three standard deviations of
the previous calibration results. All the
calibrations fell within this requirement.
Table 4-1. Calibration Results - Difference from Th-228 Calibration Energies
	Calibration Energy Levels (keV)	
Date Range	Energy 1	Energy 2 Energy 3 Energy 4 Energy 5
(2010)	238.632	583.191 860.564	1620.735 2614.533
9-27	to 11-2 -0.003 0.010	-0.039 -0.121	0.017
10-5	to 11-8 -0.003 0.011	-0.029 -0.206	0.023
10-12 to 11-6 -0.004 0.015	-0.040 -0.245	0.031
10-19 to 11-24 -0.005 0.014	-0.001 -0.320	0.043
Gamma ray counting was continued on
each coupon until the activity level of
Cs-137 on the surface had an RSD of
less than 2%. This RSD was achieved
during the first hour of counting for all
the coupons measured during this
evaluation. The final activity assigned to
each coupon was a compilation of
information obtained from all
components of the electronic assemblage
that comprises the "gamma counter,"
including the raw data and the spectral
analysis described in Section 3.1.3. Final
spectra and all data that comprise the
spectra were sent to a data analyst who
independently confirmed the "activity"
number determined by the
spectroscopist. When both the
spectroscopist and an expert data analyst
independently arrived at the same value
the data were considered certified. This
process defines the full gamma counting
QA process for certified results.
The background activity of the concrete
coupons was determined by analyzing
four arbitrarily selected coupons from
the stock of concrete coupons used for
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this evaluation. The ambient activity
level of these coupons was measured for
at least two hours. No activity was
detected above the minimum detectable
level of 2xl0"4 |iCi on these coupons.
Because the background activity was not
detectable (and the detectable level was
more than 2,500 times lower than the
post-decontamination activity levels), no
background subtraction was required.
Throughout the evaluation, a second
measurement was taken on five coupons
in order to provide duplicate
measurements to evaluate the
repeatability of the instrument. Three of
the duplicate measurements were
performed after contamination prior to
application of the decontamination
technology and two were performed
after decontamination. All five of the
duplicate pairs showed difference in
activity levels of 2% or less, within the
acceptable difference of 5%.
4.2 Audits
4.2.1 Performance Evaluation Audit
RML performed regular checks of the
accuracy of the Th-228 daughter
calibration standards (during the time
when the detector was in use) by
measuring the activity of a National
Institute of Standards and Technology
(NIST)-traceable europium (Eu)-152
standard (in units of Becquerel, BQ) and
comparing it to the accepted NIST value.
Results within 7% of the NIST value are
considered (according to RML internal
quality control procedures) to be within
acceptable limits. The Eu-152 activity
comparison is a routine QC activity
performed by INL, but for the purposes
of this evaluation serves as the
performance evaluation (PE) audit. This
audit confirms the accuracy of the
calibration of the germanium detector
critical to the results of the evaluation.
Table 4-2 shows the results of each of
the audits applicable to the duration of
the evaluation including the pre-
decontamination measurements
performed in late September. All results
are below the acceptable difference of
7%.
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Table 4-2. NIST-Traceable Eu-152 Activity Standard Check

NIST Activity
INLRML
Relative Percent
Date
(BQ)
Result (BQ)
Difference
9-15-2010
124,600
122,000
2%
10-13-2010
124,600
123,100
1%
11-10-2010
124,600
121,600
2%
4.2.2	Technical Systems Audit
A TSA was conducted during testing at
INL to ensure that the evaluation was
performed in accordance with the
test/QA plan. As part of the audit, the
actual evaluation procedures were
compared with those specified in the
test/QA plan and the data acquisition and
handling procedures were reviewed. No
significant adverse findings were noted
in this audit. The records concerning the
TSA are stored indefinitely with the
Contractor QA Manager.
4.2.3	Data Quality Audit
At least 10% of the raw data acquired
during the evaluation and transcribed
into spreadsheets for use in the final
report was verified by the QA manager.
The data were traced from the initial raw
data collection, through reduction and
statistical analysis, to final reporting, to
ensure the integrity of the reported
results.
4.3 QA/QC Reporting
Each assessment and audit was
documented in accordance with the
test/QA plan. Draft assessment reports
were prepared and sent to the Test
Coordinator and Program Manager for
review and approval. Final assessment
reports were then sent to the EPA QA
Manager and contractor staff.
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5.0 Evaluation Results
5.1 Decontamination Efficacy
The decontamination efficacy of the
ASG was measured for each
contaminated coupon in terms of percent
removal (%R) and decontamination
factor (DF). Both of these measurements
provide a means of representing the
extent of decontamination accomplished
by a technology. The %R gives the
extent as a percent relative to the activity
and the DF is the ratio of the initial
activity to the final activity or the factor
by which the activity was decreased.
These terms are defined by the following
equations:
%R = (1-Af/Ao) x 100%
DF = Ao/Af
where, A0 is the radiological activity
from the surface of the coupon before
application of ASG and Af is
radiological activity from the surface of
the coupon after treatment. While the
DFs are reported, the narrative
describing the results focuses on the %R.
Table 5-1 shows the %R and DF for
ASG. All coupons were oriented
vertically. The target activity for each of
the contaminated coupons (pre-
decontamination) was within the
acceptable range of 1 |iCi ± 0.5 |iCi. The
overall average (plus or minus one
standard deviation) of the contaminated
coupons was 1.06 |iCi ± 0.053 |iCi. The
post-decontamination coupon activities
were less than the pre-decontamination
activities showing an overall reduction
in activity. The %R averaged 71% ± 4%
and the DF averaged 3.6 + 0.62.
Overall, the %R ranged from 66% to
79% and the DF ranged from 3.0 to 4.8.
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Table 5-1. Decontamination Efficacy Results for Argonne SuperGel
Coupon
Location in Pre-Decon Activity Post-Decon Activity
Test Stand
(jiCi / Coupon)
(jiCi / Coupon)
%R
DF
Top left
1.12
0.38
66%
3.0
Top middle
1.16
0.29
75%
4.0
Top right
1.04
0.32
70%
3.3
Center left
1.03
0.33
68%
3.2
Center middle
1.01
0.32
69%
3.2
Center right
1.02
0.21
79%
4.8
Bottom left
1.07
0.32
70%
3.3
Bottom right
1.03
0.27
74%
3.8
Average
1.06
0.30
71%
3.6
Std. Dev
0.053
0.05
4%
0.62
As described above in Section 3.1, the
CC blank was included in the test stand
to evaluate the potential for CC due to
application of ASG on wall locations
above the placement of the
uncontaminated coupon. ASG was
applied to the CC blank using the same
method as for the other coupons. After
decontamination, the activity of the CC
blank was found to be 0.00216 |iCi.
This value was three times greater than
the minimum detectable level, but more
than 100 times less than the post-
decontamination activities of the
contaminated coupons. Therefore, this
detectable result suggested that cross-
contamination resulting from the
application/removal of the ASG on
coupons located above the CC blank is
possible, but that the extent of CC
observed here was minimal.
5.2 Deployment and Operational
Factors
A number of operational factors were
documented by the technician who
performed the testing with the ASG. One
of the factors was the degree of
difficulty in application. Once fully
mixed, the ASG had the look of cooked
oatmeal but was very "slippery" and
tended to slide off any plastic tools
(which is why the paint brush was used)
that were used to get the ASG onto the
concrete coupons. However, once on the
concrete, the ASG adhered rather well.
Altogether, the application of the ASG
took approximately 45 seconds per
coupon and removal with a wet vacuum
took approximately one minute per
concrete coupon. The ASG caused no
visible damage to the surface of the
coupons. Figure 5-1 shows a
photograph of ASG in the container
prior to application, ASG on a concrete
coupon and the vacuum removal of the
ASG. The personal protective
equipment (PPE) used by the technician
in the picture was required because the
work was performed in a radiological
contamination area using Cs-137 on the
concrete coupon surfaces. Whenever
radioactive contaminated material is
handled, anti-contamination PPE will be
required. The required PPE was not
driven by the use of ASG (which is non-
toxic), rather the interaction with
surfaces contaminated with Cs-137.
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Figure 5-1. ASG in container prior to application (top left), after application to
concrete coupon (bottom left), and during vacuum removal (right).
Table 5-2 summarizes qualitative and quantitative practical information gained by the
technician during the evaluation of the ASG. All of the operational information was
gathered during use of the ASG on the concrete coupons inserted into the test stand.
Some of the information given in Table 5-2 could differ if the ASG was applied to a
larger surface or to a surface that was smoother or more rough and jagged than the
concrete coupons used during this evaluation. For example, large scale mixing of ASG
for application to a city block could be performed using cement mixing trucks and
application made using viscous sprayers mounted on the mixing trucks.
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Table 5-2. Operational Factors Gathered from the Evaluation
Parameter
Description/Information
Decontamination
rate
Technology Preparation: 15 minutes to measure and mix powder with water.
The ASG is able to be used for several days after mixing as long as the ASG is
kept moist as it will dry out if left exposed to air for several days.
Application: ASG was applied with a paint brush to each concrete coupon in
approximately 45 seconds (1.9 square meters (m2)/hour (hr)). After a 90
minute dwell time, the ASG was removed with a wet vacuum and the surface
was wiped with a paper towel at a rate of approximately 1.25 minutes per
coupon (1.1 m2/hr). Aside from the wait time (which is independent of the
surface area), the application and removal rate was approximately 0.7 m2/hr for
hand application and corresponding removal.
Estimated volumes used across all the concrete coupons included 1-2 L of
ASG. Overall that volume corresponds to a loading of 5-10 L/m2.
Applicability to
irregular surfaces
Application to irregular surfaces may be problematic as the ASG could slide
off jagged edges and be hard to apply to hard to reach locations.
Skilled labor
requirement
Adequate training would likely include a few minutes of orientation so the
technician is familiar with the application technique. Larger surfaces may
require more complex equipment such as sprayer application.
Utilities
requirement
As evaluated here, electricity was required to operate the wet vacuum.
Extent of portability
At a scale similar to that used for this evaluation, the only limitation on
portability would be the ability to provide vacuum removal in remote
locations. However, for larger scale applications, limiting factors would
include the ability to apply the ASG at scale applicable to an urban
contamination (area of city blocks or square miles).
Secondary waste
management
1-2 L of ASG was applied to the concrete coupons used during this evaluation.
That volume corresponds to a waste generation rate of approximately 5 -
10L/m2. The ASG was collected entirely by the wet vacuum. Because Cs-137
was used for this testing, all waste (in vacuum and paper towels) was disposed
of as low level radioactive waste.
Surface damage
Concrete surfaces appeared undamaged.
Cost (material)
The material cost is approximately $0.30/L for the ASG (depending on source
material costs). This cost corresponds to approximately $2/m2 if used in a
similar way as used during this evaluation. Labor costs were not calculated.
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6.0 Performance Summary
This section presents the findings from
the evaluation of ASG for each
performance parameter evaluated.
6.1	Decontamination Efficacy
The decontamination efficacy (in terms
of %R) attained for decontamination
with ASG was evaluated for each
concrete coupon used during the
evaluation. When the decontamination
efficacy metrics (%R and DF) of the
eight contaminated coupons were
averaged together, the average %R for
the ASG was 71% ± 4% and the average
DF was 3.6 ± 0.62.
6.2	Deployment and Operational
Factors
The ASG had to be prepared from two
powders combined with water. The
mixture was then stirred with a drill and
mixing tool until well mixed. When fully
mixed, the mixture had the look of
cooked oatmeal, but was very "slippery"
as it tended to slide off tools that were
used to get the ASG onto the concrete
coupons. The ASG was applied to the
concrete coupons using a paint brush and
a spackling knife to smooth the ASG
across the surface. Altogether, the
application of the ASG took
approximately 45 seconds per 225 cm2
coupon and removal with a wet vacuum
took approximately one minute per
concrete coupon.
The waste generated through use of the
ASG was estimated to be approximately
5-10 L/m2. As used for this evaluation,
electricity was used to operate the wet
vacuum. Scaled up applications in
remote locations may require additional
utilities to provide means for sprayer and
larger scale vacuum removal. Minimal
training would be required for
technicians using the ASG, and the
surface of the concrete was not visibly
damaged during use of the ASG. The
material cost for ASG is approximately
$0.30/L. This corresponds to $2/m2 if
used in a similar way as used during this
evaluation. Labor and waste
management costs would be dependent
on the particular physical characteristics
of the area being decontaminated and so
were not calculated.
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7.0 References
1.	ASTM Standard C 150-07,
"Standard Specification for Portland
Cement." ASTM International, West
Conshohocken, PA, www.astm.org.
2007.
2.	Calibration and Use of Germanium
Spectrometers for the Measurement
of Gamma Emission Rates of
Radionuclides. American National
Standards Institute. ANSI N42.14-
1999. IEEE New York, NY (Rev.
2004).
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SEPA
United States
Environmental Protection
Agency
PRESORTED STANDARD
POSTAGE & FEES PAID
EPA
PERMIT NO. G-35
Office of Research and Development (8101R)
Washington, DC 20460
Official Business
Penalty for Private Use
$300

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