Valiant ‘Zero-Valent’ Effort Restores Contaminated
Grounds
Environment and Resource
Management
Originating Technology/ NASA Contribution
Dense non-aqueous phase liquids (DNAPLs) are chemical
compounds that can contaminate soil and groundwater
to the point of irreparability. These substances
are only slightly soluble in water, and are much
denser than water. Because of their solubility,
DNAPLs form separate liquid phases in groundwater,
and because of their density, DNAPLs sink in aquifers
instead of floating at the water table, making
it extremely difficult to detect their presence.
If left untreated in the ground, they can taint
fresh water sources.
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The Merritt Island
National Wildlife Refuge, which shares a boundary
with Kennedy Space Center, is home to diverse
habitats and endangered animals, including the
bald eagles pictured above. This eagle nest is
1 of 12 active nests on the premises. It is important
for Kennedy to dechlorinate dense non-aqueous
phase liquid sources in polluted water to protect
these animals and area habitats. |
Common DNAPLs include chlorinated hydrocarbon
compounds such as carbon tetrachloride, chloroform,
tetrachloroethylene, and trichloroethylene. Trichloroethylene
was used during the early days of the Space Program,
as a solvent for flushing rocket engines, and for
metal cleaning and degreasing of equipment, electronics,
and heavy machinery. As a result, areas of Cape
Canaveral’s Launch Complex 34—the site of several
historic Saturn rocket launches occurring from
1959 to 1968—were polluted with chlorinated DNAPLs.
Through the direction and guidance of Dr. Jacqueline
Quinn, an environmental engineer in the Spaceport
Engineering and Technology Directorate at NASA’s
Kennedy Space Center, a biodegradable environmental
cleanup technology was developed to reductively
dechlorinate DNAPL sources in polluted water at
Launch Complex 34. It was important for Kennedy
to nip this problem in the bud, in light of the
fact that the Space Center is also a National Wildlife
Refuge, home to thousands of shorebirds, endangered
sea turtles and eagles, manatees, alligators, and
diverse habitats that include brackish marshes
and salt water estuaries.
The success in remediating this historic launch
site has led to numerous commercial applications
that are restoring the health of our environmental
surroundings.
Partnership
Quinn and three University of Central Florida professors
developed the Emulsified Zero-Valent Iron (EZVI)
technology, with collaborative support from the
U.S. Department of Energy, the U.S. Department
of Defense, the U.S. Environmental Protection Agency
(EPA), GeoSyntec, Inc., and NASA’s Small
Business Technology Transfer (STTR) Program
at Kennedy. EZVI uses iron particles in an environmentally
friendly oil and water base to neutralize toxic
chemicals.
When speaking of the remediation work, Quinn noted,
“What makes this new technology so attractive is
that it is relatively affordable and easy to implement.
Spinoff [companies] could help clean up polluted
areas across the Nation and the world.”
To set such a cleanup effort into motion, Kennedy’s
Technology Transfer Office issued non-exclusive
licenses for EZVI to several companies, including
Weston Solutions,
Inc., and Toxicological
and Environmental Associates, Inc.
Product Outcome
Headquartered in West Chester, Pennsylvania, Weston
Solutions is a leading environmental and redevelopment
firm, dedicated to developing and implementing
solutions that safely and cost-effectively address
complex remediation challenges. Interestingly,
the company was the lead environmental contractor
for the Space Shuttle
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Weston Solutions, Inc.’s Emulsified Zero-Valent
Iron remediation technology in process at a client
site. |
Columbia recovery effort,
the largest emergency response ever conducted by
the EPA.
Following consummation of the Kennedy licensing
agreement, Weston Solutions personnel were trained
by NASA, with regard to the techniques for preparing
EZVI and applying the patented emulsion technology
in
the field.
The company and one of its industrial clients recently
evaluated the EZVI technology for application at
one of that client’s sites in Tennessee that was
impacted by high concentrations of chlorinated
solvents that could not
be remediated using conventional technology. Upon
scrupulous assessment of site conditions and endorsement
from associated regulatory agencies, EZVI was applied
to treat a zone of soil located approximately 30
feet below ground surface.
The EZVI emulsion was injected under pressure into
the target zone. Field work was conducted with
strict attention to operating pressures, the amount
applied, and the zone of injection. Further, an
application array was established onsite to position
the injection and assure even coverage over the
contaminated “footprint.”
Immediately after treatment and at subsequent intervals
thereafter, groundwater monitoring and soil-sample
analysis were conducted to track the concentration
trends and treatment effectiveness. Concentrations
of the targeted contaminant dropped dramatically
following the EZVI injection. Concurrently, concentrations
of chloride increased, showing the dechlorination
of the contaminant. According to Mike Corbin, technical
director of Weston Solutions, “the regulators and
the industrial client are very excited about the
results so far.”
Weston Solutions is currently evaluating other
sites—nationwide and in Canada—which contain DNAPLs
or near-DNAPL concentrations. The company applied
EZVI at a site in North Carolina over the past
summer. Through the company’s applications of EZVI,
additional knowledge is being gained on the performance
of the technology in different types of soil and
various other hydrogeologic environments. This
experience will provide valuable feedback to the
NASA inventors. The company has maintained open
communication with the NASA team as commercial
treatments progress.
Another licensee, Toxicological and Environmental
Associates, also received NASA training and insight
for creating a stable and reactive EZVI emulsion.
The Baton Rouge, Louisiana-based company is facilitating
the commercial application of the NASA technology
through a spinoff company it formed, called Applied
Science & Advanced Technologies, Inc. This
will be done in place of traditional pump-and-treat
methods, which can require decades of treatment
time and operational costs, and steam injection
and radio-frequency heating, which are very expensive
and can trigger contaminant mobilization. According
to the spinoff company, EZVI overcomes these limitations
by providing a method that is quick, effective,
and cost-competitive.
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This graph depicts dense non-aqueous phase
liquid concentrations before and after treatment
was applied to a contaminated site by Weston
Solutions, Inc. Concentrations of the contaminant
dropped dramatically following injection of the
treatment, and, though not depicted here, chloride
levels increased, showing that the dechlorination
was successful. |
Applied Science & Advanced Technologies
invested approximately 1 year in the commercialization
of the manufacturing process to create the emulsion.
It is currently capable of producing 2,500 gallons
per day and can efficiently expand this ability
as product demand increases. Additionally, the
company has secured an exclusive agreement with
an iron powder manufacturer. This will enable it
to control costs associated with the production
of the EZVI technology, which, in turn, should
bolster its marketability in the remediation industry.
Throughout 2005, Applied Science & Advanced
Technologies is scheduled to implement EZVI treatments
at contaminated sites in Arkansas, California,
Florida, North Carolina, and Texas.
DNAPL contamination sites may include, but are
not limited to, those created by dye and paint
manufacturers, dry cleaners, chemical manufacturers,
metal cleaning and degreasing facilities, leather-tanning
facilities, pharmaceutical manufacturers, adhesive
and aerosol manufacturers, and government facilities.
It should be noted that DNAPLs are present at 60
to 70 percent of all sites on the EPA’s Superfund
National Priorities List, a registry of national
priorities among the known or threatened releases
of hazardous substances, pollutants, or contaminants
throughout the United States and its territories.
The EZVI technology represents a major step forward
in preserving the vitality of our home planet and
its inhabitants.
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