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                        /A newsletter about soil, sediment, and ground-water characterization and remediation technologies
                                                                                                           September 2004
       Issue 14
       Wind Turbine Powers Ground-Water Circulation Well
Liitial findings from a study conducted by the
University of Missouri-Rolla (UMR) show that
wind turbines provide technically effective and
cost-efficient power for small remediation
systems such as ground-water circulation wells
(GCWs). Demonstration of this technology is
underway at the former Nebraska Ordnance
Plant Superfund site near Mead, NE. Analysis
of data collected over the first five months of
operation indicates  that the  technology is
generating more energy than consumed  by
principal components of the GCW. The wind
turbine operates in a utility grid "inter-tie" mode,
whereby both utility and wind energy are used
when wind energy is insufficient. When excess
wind energy is produced, the surplus returns to
the utility grid for other consumer use.

Data collected in 1995-1999 at a utility monitoring
station near the demonstration site indicated an
average wind speed of 6.4 m/s, a wind shear
exponent of 0.27, and a turbulence intensity of
0.17-0.21. Performance modeling using these data
indicated that a single 10-kW turbine installed
on a 100-foot tower would meet the treatment
system's anticipated energy demand. The turbine
was installed in December 2003 (Figure 1) and
connected to the facility's existing electrical
power  system the  following month for
preliminary testing.

The demonstration employs a  10-kW wind
turbine 53'stem providing energy to power a single
GCW. The well is equipped with an air stripper to
remove trichloroethene (TCE) present in ground
water at concentrations averaging 2,500 ug/L [see
October 2001 issue of Ground Water Currents,
available at www.cluin.org]. The site is underlain
by an unconfined and relatively prolific sand and
                            gravel aquifer with a saturated thickness of
                            approximately 90 feet.

                            The treatment system includes a 12-inch,
                            108-foot deep circulation well with two
                            hydraulically isolated screened  intervals
                            separated by a 19-foot unscreened interval. The
                            well operates at an average flow rate of 50 gpm
                            on a continuous basis, with the exception of
                            occasional but temporary shutdowns. Primary
                            electrical machinery of the system consists of a
                            1.5-hp submersible pump that extracts water from
                            the aquifer and delivers it to a 5-hp air stripper,
                            and a 1 -hp centrifugal pump that returns treated
                            water from the stripper sump to the well. Historical
                            data for the GCW, which has operated since July
                            2000, show little correlation between the amount
                            of purchased energy and the volume of treated
                            ground water. This is a result of environmental
                            control systems used to keep the principal GCW
                            components from overheating in the summer or
                            freezing in the winter.

                            Over the initial five months of the  study, the
                            average monthly electricity demand by principal
                            components of the GCW was 767 kW-hr. On
                            average, 817 kW-hr of electricity were generated
                            by the wind turbine each month. More than 4
                            million gallons of water were treated by the system
                            and an estimated 63 kg of TCE were removed
                            from ground water during the same time period.

                            Data analysis shows that the treatment system
                            is removing approximately 21 mg of TCE per
                            kW-hr of energy generated by the turbine.
                            Researchers estimate that the use of wind power,
                            coupled  with a well-designed climate control
                            system, may  result in a present-worth energy
                            cost savings of more than $40,000 over the 20
                                                [continued on page 2]
                                                                                   Contents
Wind Turbine Powers
Ground-Water
Circulation Well
page 1
EPA/ORD and Region 8
Evaluate In-Situ Treatment
of Acidic Mine Pit Lake     page 2

Defining a NAPL Source
Zone  Using Field Data     page 3

Superfund Document
Management System
Used  in Columbia Space
Shuttle Recovery          page 4

EPA/ORD/NRMRL
Publishes Study
on MNA Performance      page 6
    CLU-IN Resources
 The Federal Remediation Tech-
 nologies Roundtable (FRTR) is
 an interagency collaboration
 for actively sharing information
 on hazardous waste site clean-
 up technologies and the remed-
 iation marketplace. Updates on
 FRTR activities and recent pub-
 lications issued  by its member
 agencies are  continuously
 added to the FRTR web site
 (http://www.frtr.gov). Currently,
 online access is available for
 361 technology cost and
 performance reports, 144 site
 characterization  and monitoring
 case studies,  73 remediation
 process optimization case
 studies, and 54 remediation
 technology  assessment  reports.
                                                                                                        Recycled/Recyclable
                                                                                                        Printed with Soy'Canola Ink on paper thai
                                                                                                        contains al least 50% recycled fiber

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 [continued from page 1]
years of ground-water treatment anticipated
at this site.

Similarly sized off-grid wind turbine sy stems,
including installation, cost approximately
$45,000. The cost effectiveness  of wind-
powered remediation technology is expected
to be higher in remote areas where installation
of utility lines  would  incur additional
expenses, on the order of $5,000-$ 10,000.
Beneficial use of this technology is enhanced
by its reliance on renewable resources, rather
than non-renewable fossil fuel, and the
absence of air emissions during deployment.

UMR  researchers determined  that the
technology is applicable to areas with Class 3
or more wind resources, as classified by the
U. S. Department of Energy scale of 1 -7. Class
3 wind power density is defined as 150-200
W/m2 at a height of 10 m and mean wind
speeds of  5.1-5.6 m/s. Other  limiting
application factors may include the proximity
of trees and buildings that could reduce
  Figure 1. The 10-kWwind turbine system
  erected at the former Nebraska Ordnance
  Plant is possibly the technology's "first-
  ever " application for remediation
  purposes.
effective wind speed at a turbine, and sensitive
land use areas where sound generated by the
rotating turbine blades may be intrusive.

This project was funded by the U.S. EPA's
Office  of Solid Waste and  Emergency
Response through its Innovation Work Group
grant program, with additional support from
UMR, the Kansas City District Corps of
Engineers, Sergey Wind Systems, and Ohio
Semitronics. Potential follow-on work involves
operation of the GC W intermittently using a
stand-alone wind turbine system that uses
batteries to store energy for use during periods
of low or no wind.

Contributed by Curt Elmore, P.E., Ph.D.,
University of Missouri-Rolla (573-341-6784
or elmoreac@umr.edu)
             EPA/ORD and Region 8 Evaluate In-Situ Treatment of Acidic Mine Pit Lake
Over the past three years, the Anchor Hill
Pit at the Gilt Edge  Mine NPL  site near
Deadwood, SD, has been the site  of a joint
effort by EPAs Region 8 Superfund Remedial
Program and the Office of Research and
Development's Mine Waste Technology
Program (through an interagency agreement
with the U.S. DOE).  The project aimed to
demonstrate and evaluate an innovative in-
situ process for treating approximately 70
million gallons of acidic mine water containing
high levels of dissolved metals, selenium,
nitrate, and sulfate. EPA estimates that in-situ
use of this technology avoided 20-50% of
the operational costs  associated with a
conventional water treatment plant. Full-scale
use is anticipated to help meet state standards
for discharge of treated water to surface water.

The first step of this  treatment process
involved neutralizing the pit water to a pH of
approximately 7. Neutralization was achieved
by dispersing lime through a Neutra-Mill, a
floating slaker similar to equipment commonly
used to mix and disperse reagents at water
treatment plants. The second step was to add
nutrients  such as methanol, feed-grade
molasses, and phosphoric acid to the pit using
Redox-Mediated Biotransformation (RMB™)
technology.   This  process  stimulated
indigenous   bacterial   activity   that
electrochemically reduced nitrate to nitrogen
gas and subsequently reduced selenium and
sulfate. Reduction of sulfate to  sulfide
decreased    dissolved-phase    metal
concentrations through formation of metal
sulfide precipitates. The  stability of metal
sulfides that settled to the bottom of the pit
was maintained in a permanent anoxic zone.

Neutralization of the pit occurred between
March and May 2001. After several weeks of
stabilization, four nutrient additions were made
at 5- to 6-month intervals. Sodium hydroxide
was included in the last two additions to
address an unanticipated but  significant
reduction in pH (from 7 to 5) during the post-
neutralization stabilization period.

Bacterial growth during redox treatment
proceeded more slowly than expected due to
below-optimum pH conditions at the process
onset. Incorporation of wood chips in the final
nutrient addition in September 2002 provided
a successful substrate for increased bacterial
growth. Raising the pH level also  helped
reduce die amount of dissolved aluminum in
solution, which  apparently  inhibited
denitrifying bacteria.

Nitrate concentrations continued to decrease
through the winter of 2002-2003, with
nondetectable levels observed by  March
2003. Efforts were undertaken at that time to
expedite sulfate reduction. Strings  of porous
bags filled with wood chips were suspended
throughout the pit water column. In addition,
porous bags of wood chips were placed on the
                  [continued on page 3]

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[continued from page 2]
ice surface and allowed to sink to the bottom
upon melting. Consideration was also given to
developing an inoculum of sulfate-reducing
bacteria in adjacent tanks. During installation
of the porous bags of wood chips, however,
observation of black precipitates and a slight
hydrogen sulfide odor suggested that sulfate
reduction had slowly begun prior to these
efforts.

Chemical analysis confirmed sulfate reduction
in the pit and significantly  decreased
concentrations of dissolved-phase metals in
the treated water  (Figure 2).  Treatment
effectively   reduced   dissolved-phase
concentrations of copper from 43.3 to 0.008
mg/L, cadmium from 14.1 to 0.0.003 mg/L, and
zinc from 14.1 to  0.044 mg/L.  Similarly,
concentrations of selenium decreased from 26
to 12 mg/L, nitrate/nitrite dropped from 82.9 to
0.4 mg/L, and sulfate dropped from 3,270 to
2,175  mg/L. An  alkalinity increase to
approximately 400 mg/L in the deeper water
provided indirect evidence that biological nitrate
and sulfate reduction had occurred. Monitoring
of the pit over the pastyear indicated continued,
slow settling of the suspended metal sulfides.

Recent efforts have focused on transitioning to
an operational mode involving possible use of
the pit to treat acid mine water across the entire
Gilt Edge site. Over the course of treatment, the
pit lake has become permanently  stratified
whereby a strong  density gradient  (or
"chemocline") at a depth of approximately 25-30
feet separates the upper layer from the lower
layer. Acid rock drainage will be added with
nutrients to the pit at depths below the
chemocline, where the water column is expected
to maintain anoxic conditions. Following
treatment, water below the chemocline will be
removed from the pit, filtered, and aerated to
meet state ambient water quality requirements
for discharge to surface water.
                                    Figure 2. Dissolved-phase concentrations
                                    of metals in acid mine water at the Gilt
                                    Edge Mine fell more than 99% following
                                    denitrification with the onset ofsulfate
                                    reduction.
                Modifications to this technology are required
                prior to beginning the operational mode. Fine
                suspended metal sulfide precipitates in the
                deep-pit water, for example, require improved
                methods for filtering. Similarly,  improved
                methods are needed for aerating filtered water,
                which contained fine particles of elemental
                sulfur due to oxidation of excess dissolved
                sulfide. High concentrations of dissolved
                hydrogen sulfide in the deep water also will
                need resolution to ensure no health and safety
                issues exist during aeration.  Future plans
                include development of a real-time monitoring
                system in the pit for continuous observation
                of water  column  hydrodynamics  and
                geochemistry, particularly when feeding
                contaminated water to the deep portion of the
                pit.
                Contributed by Ken Wangerud,
                EPA/Region 8 (303-312-6703 or
                wangerudken@epa.gov), Norma Lewis,
                EPA/National Risk Management
                Research Laboratory (513-569-7665 or
                lewis.nortna@epa.gov), and Brian Park,
                MSE Technology Applications, Inc.
                (406-494-7415 or brian.park@jrise-ta.com)
                               Defining a NAPL Source Zone Using Field Data
      s Region 1 and Office of Research
 and Development (ORD) are working with
 a group of  PRPs to  address  dense
 nonaqueous phase liquid (DNAPL) at the
 Solvents Recovery Services (SRS) site in
 Southington, CT. Differences between the
 conceptual site models (CSMs) developed
 by the two organizations prompted an
 intensive field program in November 2003
 to delineate the DNAPL source zone and
 refine the estimated volume of overburden
 contaminated  with  DNAPL. Earlier
evaluations, which potentially supported a
technical impracticability (If) waiver based
on drinking water standards, estimated that
more  than  200,000 yd3 of DNAPL-
contaminated soil existed in addition to
800,000 yd3 of residual DNAPL zones in the
overburden aquifer. Based on the results of
a follow-on field investigation, however, the
combined volume of residual and pooled
DNAPL-contaminated overburden to be
evaluated for treatment is now estimated at
45,000yd3.
                Between 1955 and  1991, 60-100 million
                gallons of spent solvents were processed
                on a 4-acre parcel at the SRS site. Liquid
                waste was brought to the site in steel drums
                and tank trucks, and  other wastes were
                managed in aboveground tanks.  Still
                bottoms and sludge were placed in two
                unlined lagoons  that  occasionally
                overflowed and discharged into the nearby
                Quinnipiac River via an unlined drainage
                ditch. A12-acre ground-water contaminant
                                 [continued on page 4]

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[continued from page 3]
plume is present in the overburden, which
consists of 15-50 feet of fluvio-glacial
sediment and till. A slightly larger plume
exists within the underlying fractured
bedrock-a  thickly-bedded, red,  arkosic
Triassic sandstone. The plume in the
overburden ground water has affected two
municipal water supply wells located 1,300
and 2,000 feet south of the site.

The initial estimate of 200,000 yd3 was based
on the  visual observation of DNAPL,
historical records, and indirect indicators,
such as ground-water samples exceeding
1 % of the DNAPL's effective solubility. The
field program assessed  whether  a
ground-water sample containing  10% of
the effective solubility indicated that a
DNAPL residual or  free-phase mass was
immediately upgradient or just "somewhere"
upgradient.

The field program involved advancing 39
borings over a one-week period. Two direct-
push rigs ran continuous cores to the point
of refusal, which was commonly at the top
of bedrock or till. Refusal was encountered
about 15 feet below ground surface on the
west  side  of the  site,  becoming
progressively deeper (30-35 feet) to the east.

DNAPL was judged to be present in a core
if it was directly observed or if a hy drophobic
dye indicated its presence in soil  samples.
The plastic  liners of each core were cut in
half lengthwise, visually inspected, and
Figure 3. Based on the results of field tests,
EPA now estimates that 45,000 yd3 of
DNAPL-contaminated overburden at the SRS
site require remediation.
                                       screened with a photoinonization detector
                                       (PTD). If the PID reading in any part of the
                                       core exceeded 100 ppm, the core was tested
                                       in a 40-mL vial containing equal portions of
                                       soil, water, and hy drophobic dye. The
                                       formation of a red "collar" around the top of
                                       the vial after vigorous shaking indicated the
                                       presence of residual DNAPL in soil.

                                       DNAPL was not observed in areas where
                                       previously its presence was implied only by
                                       indirect  indicators such as dissolved-phase
                                       concentrations. Data collected during the field
                                       program were integrated into an updated
                                       C SM that now reflects a much smaller source
                                       zone (Figure 3). Based on the results of this
                                       field investigation, which was estimated to
                                       cost less than $ 1OOK, a TI waiver for cleanup
                                       in the overburden is no longer probable.

                                       Updates to the CSM will continue as remedial
                                       alternatives for the overburden are evaluated
                                       and implemented. A feasibility  study is
                                       underway  to   evaluate   the   use  of
                                   bioremediation, enhanced bioremediation,
                                   thermal treatment, chemical oxidation,
                                   and hydraulic  flooding  in  treating
                                   the  overburden.  Pilot  testing   of
                                   phytotechnology  began in 2002 with the
                                   planting of poplar trees.

                                   A pump and treat system is in place to
                                   address contamination in the bedrock.
                                   In addition, the potential for natural
                                   attenuation  is being evaluated through
                                   analysis    of   native    microbial
                                   (Dehalococcoides)  populations   in
                                   Geoprobe® soil samples. Additional field
                                   tests will be conducted to evaluate the extent
                                   of DNAPL contamination in bedrock and to
                                   support any associated determination
                                   regarding a TI waiver.

                                   Contributed by Karen Lumino, EPA'
                                   Region 1 (617-918-1348 or
                                   lumino.karen@epa.gov) and Steve
                                   Mangion EPA/ORD (617-918-1452 or
                                   mangion.steve@epa.gov)
                                                                  —,.,.-----N
                                                                         ,»•*                   i     i  '
                                                                      '**                      v    '
                                              ITENTIAL AREA FOR       ff                         \   / ?
POTENTIAL
SOURCE ZONE TREATMENT-^
                                               Ground-water samples exceeding 10% DNAPL effective solubility
                                               DNAPL presence indicated by visual observation or hydrophobia dye testing of soil
                                             + Other ground-water sampling locations
    Superfund Document Management System Used in Columbia Space Shuttle Recovery
On February 1, 2003, the STS-107 space
shuttle Columbia, traveling over 200,000 feet
in altitude, broke apart over central Texas
and eastern Louisiana. Response to the
accident was shared by the U.S. Federal
Emergency Management Agency (FEMA),
the National Aeronautics and Space
                                       Administration (NASA), and EPA, which was
                                       given authority to run field recovery
                                       operations. EPAs Region 6 coordinated the
                                       effort, using in large  part the  Superfund
                                       Document Management System (SDMS)
                                       already  employed by headquarters and
                                       regional offices.
                                   Field work immediately began with four-
                                   member crews walking at ami's length to
                                   survey the ground for any material related
                                   to the crash. Vegetation at that time of year
                                   was relatively bare, but eastern Texas pine

                                                    [continued on page 5]

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[continued from page 4]

forests and western Louisiana swamps and
lakes complicated  the task. As spring
approached,   increasing   vegetation,
venomous snakes, insects, and wild havilina
hogs added additional problems during the
search and recovery work. Over 10,000
volunteers representing or supplementing more
than 90 organizations, including EPA, the Texas
Forest Service, and the U.S. Forest Sendee,
joined the task of canvassing a debris field the
size of West Virginia.

Each search team carried into the field a hand-
held personal digital assistant (PDA) computer
with pre-loaded data forms, a  digital camera,
and a geographic information system (GIS)
transponder. When anything appearing to be
related to the shuttle was found, the GIS position
was documented on a PDA form. Digital
photographs of the item were taken and other
descriptive data were noted in the PDA.

Precautions were taken with each item of
evidence. Worker protection was a concern due
to the presence ofhydrazine, a highly toxic rocket
propellant coating much of the debris. Each item
or container was affixed an identification tag
and transferred to a collection facility where
NASAand the Federal Aviation Administration
worked to reconstruct a layout of the shuttle.
Each evening as the search crews returned to
one of five established field stations, the
PDAs were placed in a bank of cradles and
linked to a set of GIS servers. PDA data were
transferred to an existing emergency-response
computer application that was up-scaled to
collate the large volume of information coming
from the field. Debris points were plotted onto
maps of the search areas and used by EPAs
on-scene coordinators to plan the next day's
search activities.

Region 6 information management personnel
worked with emergency response staff to
develop methods for documenting the diverse
data produced in the field. Within one week of
the accident, a commercially -developed mobile
unit prototype called "SUREAIM" was
delivered to a Lufkin, TX, command post to
capture records. Contractors trained in its use
and in Region 6 electronic records operations
also arrived within days. In order to use minimal
amounts of paper documentation, SUREAIM
employed a paper scanning component, a high-
speed workstation, and remote access software
(AAA virtual private network extranet tokens
under pilot in Region 6).

SURE AIM records typically were converted in
the field to Adobe PDF files and transferred daily
through the Agency firewall to a Region 6
automated Domino  workflow tool called
"ExpressLink." Key metadata were assigned to
forms and associated documents and saved in
ExpressLink, which triggered placement of the
information in the SDMS.

Two years earlier Region 6 had re-engineered
the client-server SDMS into a fully web-based
form known  as SDMS2 in order to receive
electronic records and to provide a more textured
information management  environment for
Superfund staff, records managers, and support
contractors. The major procedural innovation
made possible by SDMS2, in tandem with the
PDA forms, was to move records management
from a relatively  passive "receipt of records"
mode to one  in which remediation staff was
involved in the early lifecycle  of data. This
allowed record providers to immediately transmit
items to the records program, while retaining
unlimited access, and provided multiple parties
joint and simultaneous record access.

During the high-pressure shuttle recovery, the
ability of field staff to drop records off at the
SUREAIM station with knowledge that the
information would be rapidly processed and
available for  on-demand access was a great
benefit. EPA currently is considering creation of
documentation teams that could perform the
same functions in emergency response centers
and field settings. GIS data management during
the recovery involved conversion of map layers
to scalable vector graphics and export of a
searchable database (with linked photos and
documents) into a new SDMS2 component.

Subsequent assessment of the field recovery
indicated that 99% of the documentation was
captured at or just after lifecycle creation. It also
was  determined that field  contractors had
successful access to site-specific information
and offsite discussions regularly. The effort
demonstrated that records can be transformed
from relatively restricted documentation of past
events into front-line decision-making tools.

EPA concluded its field operations in May 2003,
less than four months after the accident, with
significantly more of the spacecraft recovered
than expected. Within two weeks of closing
the field stations, full documentation of the
events was available in SDMS2 (with no paper
backlog),  and a hard drive containing the
records was provided to NASA soon thereafter.
SDMS2 and other tools used for the shuttle
recovery have since emerged in Region 6 as
instruments applicable to more routine field
operations. With more than 50 million pages of
national Superfund records, management of
SDMS2 was transferred to EPA headquarters
early this year.

Contributed by Steven Wyman, EPA/Office of
Superfund Remediation and Technology
Innovation (and formerly of Region 6
(703-603-8882  or wyman.steve@epa.gov)
              Contact Us
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       Technology News and Trends
      welcomes readers'  comments
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           Phone:703-603-7199
             Fax:703-603-9135

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                 Technology
              News and Trends
      Solid Waste and
      Emergency  Response
      (5102G)
EPA 542-N-04-005
September 2004
Issue  No.  14
 United States
 Environmental Protection Agency
 National Service Center for Environmental Publications
 P.O. Box 42419
 Cincinnati, OH 45242
Presorted Standard
Postage and Fees Paid
EPA
Permit No. G-35
Official Business
Penalty for Private Use $300
                         EPA/ORD/NRMRL Publishes Study on MNA Performance
L
  EPA's ORD/National Risk Management
  Research Laboratory' (NRMRL) recently
  completed a study on the performance
  monitoring of remedies that rely on natural
  attenuation of contaminants. The study's
  results are now available in the April 2004
  report entitled Performance Monitoring of
  MNA Remedies for VOCs in Ground Water.
  As part of this effort, NRMRL developed
  technical recommendations regarding the
  types of monitoring parameters and
  analyses that are useful  for evaluating
  monitored natural attenuation (MNA)
  during the design and implementation of
  MNA plans. NRMRL found that effective
  monitoring system designs need to be based
  on a  thorough  understanding of the
  migration and ultimate fate of contaminants
  in site-specific environments.
The study found that an effective monitoring
program includes routine evaluations of
institutional controls and measurements of
contaminant, geochemical, and hydrologic
parameters. These data are used to evaluate
changes  in  three-dimensional  plume
boundaries,   contaminant   mass   and
concentration,  and  hydrological  and
geochemical changes that may indicate
changes in remedy performance.

Continuation of an  MNA program is
appropriate when contaminant concentrations
behave according to remedial expectations,
and ground-water flow and geochemical
parameters remain within acceptable ranges.
Program modifications may include increases
or decreases in  monitoring parameters,
frequency, or locations to reflect changing
        conditions or an improved understanding
        of natural attenuation processes at a site.
        Implementation of a contingency or
        alternative remedy may be triggered by:
         > Increasing contaminant concentrations
           or unexpected trends;
         > Contaminant  migration beyond the
           established plume  or compliance
           boundaries;
         > Insufficient rates of contaminant reduc-
           tions;
         > Land or ground-water use changes with
           the potential to reduce protectiveness
           of the remedy; or
         > Unacceptable risks to receptors.
        The complete publication (EPA 600/R-04/
        027) is available  online  from  CLU-IN at
        http://www.cluin.org/publ .cfm.
                                                                              J
EPA is publishing this newsletter as a means of disseminating useful information regarding innovative and alternative treatment techniques and
technologies. The Agency does not endorse specific technology vendors.

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