&EPA
EPA 600/R-11/084 | August 2011 ] www.epa.gov/ord
United States
Environmental Protection
Agency
Technology Evaluation Report
CBI Polymers
DeconGel® 1101 and 1108 for
Radiological Decontamination
Office of Research and Development
National Homeland Security Research Center

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EPA 600-R-11-084
June 2011
Technology Evaluation Report
CBI Polymers
DeconGel® 1101 and 1108 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. NHSRC, through TTEP, 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
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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
Lukas Oudejans
Eletha Brady-Roberts
Lyndsey Kelly
Terry Stilman
University of Tennessee
Dr. Howard Hall
United States Department of Energy's Idaho National Laboratories
Battelle Memorial Institute

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Contents
Disclaimer	i
Foreword	ii
Acknowledgments	iii
Abbreviations/Acronyms	vi
Executive Summary	vii
1.0 Introduction	1
2.0 Technology Description	3
3.0 Experimental Details	4
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	9
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	16
6.1	Decontamination Efficacy	16
6.2	Deployment and Operational Factors	16
7.0 References	18
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Figures
Figure 2-1. DeconGel® 1101 and DeconGel® 1108	3
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. Concrete coupon during coating removal	14
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	9
Table 5-1. Decontamination Efficacy Results for DG-1101	12
Table 5-2. Decontamination Efficacy Results for DG-1108	12
Table 5-3. Operational Factors Gathered from the Evaluation	15
v

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Abbreviations/Acronyms
ANSI	American National Standards Institute
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
cm3	cubic centimeter
DARPA	Defense Advanced Research Projects Agency
DG	DeconGel®
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
g	gram
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
vi

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Executive Summary
The U.S. Environmental Protection Agency's (EPA's) 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 its Technology Testing and Evaluation
Program (TTEP), NHSRC recently evaluated the performance of DeconGel® (DG) 1101
and DG 1108 strippable coatings from CBI Polymers (Honolulu, HI). The objective of
evaluating DG 1101 and DG 1108 was to test their ability to remove radioactive cesium
(Cs)-137 from the surface of unpainted concrete.
Experimental Procedures. DG 1101 and DG 1108 were applied as paint-like coatings
and then cured in order to bind the Cs-137 so the cured coating containing CS-137 could
be removed from the surface causing little or no surface damage. Prior to the evaluation,
eight 15 centimeter (cm) x 15 cm unpainted concrete coupons were contaminated with
Cs-137 at a level of approximately 1 microcurie (jaCi, measured by 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. Following manufacturer's
recommendations, both DG 1101 and DG 1108 coatings were applied and removed twice
for each coupon (four coupons total for each technology) before the residual activity of
the contaminated coupons was measured. 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 percent removal and decontamination
factor attained by the DG 1101 and DG 1108 was evaluated for each concrete coupon
used during the evaluation. When the decontamination efficacy metrics (%R and DF) of
the four contaminated coupons were averaged together, the average %R for DG 1101 was
45 ± 7% and the average DF was 1.9 ± 0.24. The average %R for DG 1108 was 67 ± 9%
and the average DF was 3.2 ± 0.87.
Both the DG 1101 and DG 1108 were painted onto the concrete coupons with a 4 inch
paint brush. The time required to apply each coating to a coupon was an average of 30
seconds for each coat that was applied. During this evaluation, two coats were applied to
each coupon and then the coupons were allowed to dry overnight and the coatings were
removed. That cycle was repeated once.
The dry coatings were removed by first scoring the surface of the coupons (covered with
dried coatings) into four sections with a utility knife and using the tip of the knife to free
corners of the dried coating so they could be pulled off the surface by hand. The dry
coatings were removed from each coupon in an average of 1 minute 24 seconds. The
technician who did the removal became more adept at the removal task during the second
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removal as the average time required to remove the dry coatings from one coupon
decreased between the first and second removals. These application and removal times
are specific to the experimental scenario used during this evaluation. If these coatings
were applied to larger surfaces, larger paint application tools such as rollers or sprayers
may be used which would likely impact the application rate. In addition, larger sections
of dry coating could likely be removed in a similar amount of time as for the small
coupons. No utilities were required for use of DG 1101 and DG 1108 making them
decontamination options that are amenable to use in remote settings. The only limitation
on the portability of DG 1101 and DG 1108 is the ability to transport an adequate amount
of the wet material to the contaminated site. Minimal training would be required for
technicians using DG1101 and DG 1108, and the surface of the concrete was not
damaged during application and removal of the DG 1101 and DG 1108.

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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.
Under TTEP, NHSRC evaluated the
performance of two technologies from
CBI Polymers, LLC (Honolulu, HI),
DeconGel® 1101 and 1108 (hereafter
referred to as DG 1101 or DG 1108) 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 DG 1101 and DG 1108,
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 DG 1101 and DG
1108 took place October 25-27, 2010,
with the pre-evaluation activity
measurements occurring in September
2010 and the post-evaluation activity
measurements occurring in early
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 DG 1101 and DG 1108.
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 Technology Description
This technology evaluation report
provides results on the performance of
DG 1101 and DG 1108 under laboratory
conditions. The following is a
description of DG 1101 andDG 1108,
based on unverified information
provided by CB1 Polymers.
DG 1101 and DG 1108 are strippable
coatings designed for safely removing
radioactive contamination or as a
covering to contain contamination. DG
1101 and DG 1108 are sold as a paint-
like formulation. Application options
include use of a paint brush, roller, or
sprayer. The water-based wet coating
formula for T'
%ZnUc,ld<*. Heavy M
Contaminants
te""tified peelabl''
Figure 2-1. DeconGel 1101 and DeconGel" 1108
(hydrogel) can be applied to horizontal,
vertical or inverted surfaces and can be
applied to most surfaces including bare,
coated and painted concrete, aluminum,
steel, lead, rubber, plexiglas, herculite,
wood, porcelain, tile grout, and vinyl,
ceramic and linoleum floor tiles.
Following application, the coating
requires approximately 12 hours to cure
prior to removal. When dry, the product
binds the contaminants into a polymer
matrix. The dried coating containing the
encapsulated contamination can then be
peeled off the surface and di sposed of.
More information is available at
www. decongel. com.
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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
solution of cesium chloride, which
corresponded to an activity level of
approximately 1 |iCi over the 225 square
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2
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
constaicted 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
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 liter (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
contaminant solution is effectively
distributed across the surface of the
coupon.
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 DG 1101
and DG 1108. These measurements
were made using an intrinsic high purity
germanium detector (Canberra LEGe
Model GL 2825R/S, Meriden, CT).
After being pl aced 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 less than 2%. Gamma-ray
spectra acquired from Cs-137
contaminated coupons were analyzed
using INL Radiological Measurement
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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 m 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.
1
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 DG 1101 and DG
1108. DG 1101 was applied to the
coupons in positions I, 2, 4, and 7 while
DG 1108 was used on the coupons in
positions 3, 5, 6, 8 (blank coupon), and
9. Both DG 1101 and DG 1108 were
applied to the coupons in the order given
above 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 application of DG 1101 and DG
1108 was performed in the same way
using a standard four inch paint brush.
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The specifications of the paint brush
were not critical as a perfectly smooth
application was not required. The paint
brush was loaded with the wet coatings
by dipping the brush into a plastic
bucket containing the wet coatings and
then the wet coatings were applied
generously until the entire surface of the
coupon was covered. The paint brush
was then used to work the wet coatings
into the surfaces. Then the brush was
used to smooth the applied wet DG 1101
and DG 1108 on each concrete coupon.
If there were areas of the coupons that
were not covered completely, additional
wet DG 1101 or DG 1108 was added.
The first coat of the DG 1101 or DG
1108 was allowed to set for 2 hours and
a second coat was added on top of the
initial coat following the same method.
The coupons with the wet DG 1101 and
DG 1108 were allowed to dry overnight.
The dry coatings were removed by first
scoring the surface of the coupons (now
covered with dried coatings) into four
sections with a utility knife and using the
tip of the knife to free corners of the
dried coating so they could be pulled off
the surface by hand. This process was
repeated once. The overall
decontamination method for DG 1101
and DG 1108 included:
1.	Apply wet coating followed by
two hour drying time and apply a
second coat
2.	Dry overnight
3.	Remove dried coatings
4.	Apply wet coating followed by
two hour drying time and apply a
second coat
5.	Dry overnight
6.	Remove final dried coatings.
The temperature and relative humidity
(RH) were recorded at the application
and removal times. The temperature in
all four instances was between 19 °C (66
°F) and 21 °C (70 °F) and the RH was
always between 20% and 22%. Because
the room in which the evaluation was
performed was climate-controlled, these
conditions did not vary significantly
throughout the evaluation. According to
the vendor, these conditions were
acceptable for use of the DG 1101 and
DG 1108.
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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). 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 gives 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 11-16 -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 comprise 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 arrived at 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 2x10~4 |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 gives 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%.
Table 4-2. NIST-Traceable Eu-152 Activity Standard Check	
NIST Activity INL RML Relative Percent
Date	(BQ)	Result (BQ)	Difference
9-15-201	0	124,600	122,000	2%
10-13-201	0	124,600	123,100	1%
11-10-201	0	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.
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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 DG
1101 and DG 1108 was measured for
each contaminated coupon in terms of
percent removal (%R) and
decontamination factor (DF). Both of
these parameters 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 ofDG 1101 orDG 1108 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.
Tables 5-1 and 5-2 give the %R and DF
forDG 1101 andDG 1108, respectively.
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 1.10 |iCi ± 0.03 |iCi and
1.07 |iCi ± 0.02 |iCi for the coupons
used for DG 1101 and DG 1108,
respectively. The post-decontamination
coupon activities were less than the pre-
decontamination activities showing an
overall reduction in activity for both
technologies. For DG 1101, the %R
averaged 45 ± 7% and the DF averaged
1.9 ± 0.24. Overall, the %R ranged from
35% to 52% and the DF ranged from 1.5
to 2.1. For DG 1108, the %R averaged
67 ± 9% and the DF averaged 3.2 ± 0.87.
Overall, the %R ranged from 57% to
75% and the DF ranged from 2.3 to 4.0.
A t-test was performed on the two data
sets in order to determine the likelihood
of generating the observed %R data if
the data sets were not different. The
probability of generating these data sets
if the data sets were not significantly
different was 0.045 so at a 95%
confidence interval, the DG 1101 and
DG 1108 were considered significantly
different from one another.
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Table 5-1. Decontamination Efficacy Results for DG-1101
Coupon
Location in
Pre-Decon Activity
Post-Decon Activity


Test Stand
(jiCi / Coupon)
(jiCi / Coupon)
%R
DF
Top left
1.10
0.72
35%
1.5
Top middle
1.07
0.51
52%
2.1
Center left
1.13
0.61
46%
1.8
Bottom left
1.08
0.56
48%
1.9
Average
1.10
0.60
45%
1.9
Std. Dev
0.026
0.09
7%
0.24
Table 5-2. Decontamination Efficacy Results for DG-1108
Coupon




Location in
Pre-Decon Activity
Post-Decon Activity


Test Stand
(jiCi / Coupon)
(jiCi / Coupon)
%R
DF
Top right
1.07
0.28
74%
3.8
Center middle
1.09
0.27
75%
4.0
Center right
1.04
0.45
57%
2.3
Bottom right
1.08
0.42
61%
2.6
Average
1.07
0.36
67%
3.2
Std. Dev
0.022
0.09
9%
0.87
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 DG 1101 and DG 1108 on
wall locations above the placement of
the uncontaminated coupon. DG 1101
was applied to the contaminated coupon
in the top middle position and DG 1108
was applied to the contaminated coupon
in the center middle position. Upon
application of the DG 1108 to the
contaminated center middle coupon,
there was a small amount of wet DG
1108 that dripped onto the
uncontaminated coupon in the bottom
middle position. DG-1108 was then
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 0.0076 |iCi. This
value was five times greater than the
minimum detectable level, but more than
50 times less than the post-
decontamination activities of the
contaminated coupons. Therefore, this
detectable result suggested that cross-
contamination resulting from the
application/removal ofDG 1101 and
1108 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 DG 1101
and DG 1108. One of the factors was the
degree of difficulty in application and
removal. The application of both
technologies was described in Section
3.2. Both the DG 1101 and DG 1108
technologies were painted onto the
concrete coupons with a four inch paint
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brush. The time required to apply each
coating to a coupon was an average of
30 seconds for each coat that was
applied. The overall time required to
remove the coatings from each coupon
was an average of 1 minute and 24
seconds. However, it was clear that the
technician who did the removal became
more adept at the removal task during
the second removal as the average time
required to remove the dry coatings from
the concrete from one coupon dropped
from 1 minute 51 seconds for the first
removal to just 57 seconds for the
second removal. These application and
removal times are applicable only to the
experimental scenario including these
rather small concrete coupons. If these
coatings were applied to larger surfaces,
larger paint application tools such as
rollers or sprayers may be used which
would likely impact the application rate.
In addition, larger sections of dry
coating could likely be removed in a
similar amount of time as the small
coupons.
DG 1101 and DG 1108 coatings behaved
very similarly during application and
removal. The DG 1101 was a rather
viscous gel when wet and therefore
tended to stay on the coupon very well
upon application. Removal of the DG
1101 was very easy as it was easily
pulled from the concrete surface once a
corner was freed by a knife.
The DG 1108 was less viscous and
tended to run down the coupon upon
application with some of the wet DG
1108 running off of the coupon, leaving
what appeared to be a thin layer of wet
coating. While DG 1108 may have been
less viscous than DG 1101 when wet, the
DG 1108 was removed in a fashion
similar to DG 1101 after drying. While
the removal method was practically
similar, the DG 1108 required some
additional effort to remove the dry
coating from the surface of the concrete
as the DG 1108 seemed to be adsorbed
more strongly.
Figure 5-1 shows a photograph of an
uncontaminated coupon during removal
of the DG 1101 during a dry run outside
the radiological containment tent. In this
instance, the dry coating was able to be
removed as one large piece. When using
the DG 1101 and DG 1108 within the
test stand, the technician scored the
coupons into four sections and removed
each section separately. The coupon
surfaces were left undamaged by the DG
1101 and DG 1108. The personal
protective equipment (PPE) used by the
technicians (including respirators and
full anti-contaminatino PPE) 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 and any waste (from removal of
DG 1101 and DG1108) will be
considered low level radioactive waste
(and will need to be deposed of
accordingly). The PPE was not driven
by the use of DG 1101 and DG 1108
(which are not hazardous), rather the
interaction with surfaces contaminated
with Cs-137.
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Figure 5-1. Concrete coupon during coating removal.
Table 5-3 summarizes qualitative and quantitative practical information gained by the
technician during the evaluation of DG 1101 and DG 1108. All of the operational
information was gathered during use of DG 1101 and DG 1108 on the concrete coupons
inserted into the test stand. Some of the information given in Table 5-3 could differ if the
DG 1101 and DG 1108 were 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.
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Table 5-3. Operational Factors Gathered from the Evaluation
Parameter
Description/Information
Decontamination
rate
Technology Preparation: No preparation was required as wet DG 1101 and DG
1108 was poured out of a bottle ready to use.
Application: Average of 30 seconds to apply each coat of wet coating to each
coupon for both DG 1101 and DG 1108. Two hours were allowed to elapse and
then a second coat was added. Then an overnight drying time was required before
removal of the dry coating. The limiting factor of decontamination rate is the
surface area covered before the overnight drying time. Larger surfaces would
require larger roller brushes or paint sprayer application.
Approximately 125 mL total of each wet coating was used for each application to
the concrete coupons. That volume corresponds to approximately 25-30 mL per
coupon for a loading of 1.2 L/square meter (m2).
Applicability to
irregular surfaces
Application to irregular surfaces would not seem to be problematic as the wet
coatings can be painted or sprayed into hard to reach locations. Removal of the
dry coating may take longer if the dry coating fractures on jagged edges or gaps in
surfaces.
Skilled labor
requirement
Adequate training would likely include a few minutes of orientation so the
technician is familiar with the application technique and the required drying time.
Utilities
requirement
No utilities were required to complete the experimental plan described in this
report. If sprayer was used to apply DG 1101 or DG 1108, applicable power
would be required.
Extent of portability
The limiting factors of portability for the DG 1101 and DG 1108 would include
the ability to transport adequate wet coating and application tools to the job
location.
Secondary waste
management
Amount of secondary waste generated was based on the dried coating from
coating applied to an uncontaminated coupon. The coating from one coupon
weighed 3.6 grams (g). Therefore, the dried coatings from all nine coupons for
two application and removal cycles would correspond to 65 g of waste with a
volume of approximately 51 cubic centimeters (cm3). Assuming two applications
of two coats and two corresponding removals, this procedure corresponds to a
waste generation of 319 g/m2 and a volumetric waste generation of 252 cm3/m2 of
surface. Because Cs-137 was used for this testing, all waste (liquid and solid gel)
was disposed of as low level radioactive waste.
Surface damage
Concrete surfaces appeared undamaged.
Cost (material)
The material cost is $40/L for DG 1101 and $40/L for DG 1108 which
corresponds to approximately $40/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 the DG 1101 and DG
1108 for each performance parameter
evaluated.
6.1	Decontamination Efficacy
The decontamination efficacy (in terms
of %R) attained by the DG 1101 and DG
1108 was evaluated for each concrete
coupon used during the evaluation.
When the decontamination efficacy
metrics (%R and DF) of the four
contaminated coupons were averaged
together the average %R for DG 1101
was 45 ± 7% and the average DF was
1.9 ± 0.24. The average %R for DG
1108 was 67 ± 9% and the average DF
was 3.2 ±0.87. These results were
determined to not be significantly
different from one another.
6.2	Deployment and Operational
Factors
Both the DG 1101 and DG 1108 were
painted onto the concrete coupons with a
4 inch paint brush. The time required to
apply each coating to a coupon was an
average of 30 seconds for each coat that
was applied. Overall, 125 mL of each
coating was used for each coat applied to
the coupons used during this evaluation.
This value corresponded to a coverage
rate of 0.83 m2/L. During this
evaluation, two coats were applied to
each coupon and then the coupons were
allowed to dry overnight and the
coatings were removed. That cycle was
repeated once.
The dry coatings were removed by first
scoring the surface of the coupons (now
covered with dried coatings) into four
sections with a utility knife and using the
tip of the knife to free corners of the
dried coating so they could be pulled off
the surface by hand. The dry coatings
were removed from each coupon in an
average of 1 minute 24 seconds. The
technician who did the removal became
more adept at the removal task during
the second removal as the average time
required to remove the dry coatings from
one coupon dropped from 1 minute 51
seconds for the first removal to just 57
seconds for the second removal. These
application and removal times are
specific to the experimental scenario
used during this evaluation. If these
coatings were applied to larger surfaces,
larger paint application tools such as
rollers or sprayers may be used which
would likely impact the application rate.
In addition, larger sections of the coating
could likely be removed in an amount of
time similar to the time required for
removal of coating from small coupons.
The waste generated through use of
DG1101 and DG 1108 was estimated to
be approximately 319 grams (g)/m and
a volumetric waste generation of 252
3 2
cubic centimeters (cm )/m of surface.
Because this technology evaluation
included Cs-137, all the waste was
disposed as low level radioactive waste.
No utilities were required for use of DG
1101 and DG 1108 making them
decontamination options that are
amenable to use in remote settings. If a
sprayer was used to apply DG 1101 or
DG 1108, applicable power would be
required. The only limitation on the
portability of DG 1101 and DG 1108 is
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the ability to transport an adequate
amount of the wet material to the job
site. Minimal training would be required
for technicians using DG1101 and DG
1108, and the surface of the concrete
was not damaged during application and
removal of the DG 1101 and DG 1108.
The material cost is $40 per L for DG
1101 or DG 1108 which corresponds to
approximately $40/m 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. ANSIN42.14-
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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