category includes the chemicals that constitute propellants,
explosives, and pyrotechnics, and refers to issues associated with
category includes gasoline, jet fuel, grease and other petroleum
hydrocarbons, as well as fuel additives such as MTBE (methyl tertiary
Organic Compounds (VOC)
includes solvents that easily change phases, or evaporate. This
attribute often makes the compound easier to detect and remove. Very
frequently, these compounds are chlorinated. Typical contaminants of
this type are Trichloroethene (TCE) and its daughter products such as
|Semi-volatile Organic Compounds (SVOC)
category includes contaminants that are more difficult to remove
because they do not easily change phases, and often adsorb onto soil
particles. Typical contaminants of this type are Polychlorinated
Biphenyls (PCB), and polynuclear aromatic hydrocarbons (PAHs), such as
coal tars and creosote.
and Herbicides (Pe)
includes contaminants that by design are very toxic or damaging to the
category includes metals such as lead, chromium and arsenic, but does
not include radioactive metals.
includes contaminants that are radioactive. Typical contaminants
include tritium (radioactive hydrogen) and uranium.
|Unexploded Ordnance (UXO)
category includes unexploded bombs and shells. as well as discarded
military munitions, that may be found
at impact ranges and disposal site, as well as randomly in the
environment. Contaminants in this category present hazards due to
||This category covers
any situation for which the selection of the technology does not depend
upon the contaminant type.
category consists of the vapors that are emitted from extraction and
treatment systems. For example, typical pump-and-treat systems extract
groundwater and strip it of contaminants. These contaminants are
usually vaporized, and can either be discharged directly to the
atmosphere or captured or destroyed.
and Leachate (GW)
environment consists of layers of granular materials, clay and rock.
When all the void spaces in these materials all filled with water, the
material is saturated. The water flowing in these spaces is called
groundwater. In landfills, liquids that run through the fill material
and collect in pockets in or below the landfill is called leachate.
|Surface Water and Sediment (SW)
category consists of waters that flow on top of the ground surface
(surface waters) and the sediments that lie underneath this water.
Often, surface waters carry a large variety of contaminants that have
been carried off from the land surface and are deposited in sediments.
||This category is the
zone either at or below the ground surface that is above saturated
zones. This is referred to as the unsaturated subsurface or the vadose
|Landfill Materials (L)
category contains the diverse materials found in solid and hazardous
waste landfills. Wastes may still be in containers. Landfills are
man-made and deliberate locations where a variety of wastes may be
includes building surfaces and pipes. Contaminants may range from
asbestos to lead paint.
|Indoor Air/Soil Gas
|This refers to contaminant vapors found inside structures, in
the vadose zone (between groundwater and the surface), and at times the
ambient (outdoor) air.
|Advanced Analytical Methods, Characterization, and
during and after a site is remediated, contaminants are continually
analyzed, and the site must be characterized and monitored. Typical
technologies in this category are the cone pentrometer and advanced
sensors. To reduce costs, innovative analytical methods that can be
performed in the field have been developed and are included in this
||After it is decided
that contamination is present, one of the first questions that is asked
is whether the contaminants can be treated in place (i.e., in-situ).
Treatment could include destruction, or reduction in mobility or mass.
Typical in-situ methods range from phytoremediation (absorption and
metabolism by plants) to permeable barrier walls (walls of material
that react with an agent to render it harmless).
contaminants cannot be successfully treated or destroyed in place, they
have to be removed and treated, contained, or disposed of. This
category includes removal enhancements such as directional drilling and
contaminants must be treated or destroyed. A typical technology in this
category is an incinerator.
is remediation strategy that is selected when treatment is impractical.
It is often used, or in combination with in-situ treatment. The most
common containment measures are capping landfills and placing barriers
in the subsurface to impede migration. Some technologies apply to more
than one contaminant or media. For example, if a technology addresses
two contaminant types, it may be found by checking either of the
appropriate boxes. In some cases, technologies are not specific to
contaminant or media. In this case there is a box in each column that
addresses these technologies. Also, some technologies are a combination
of technology types. In this case, the technology can be found in
either appropriate category.
generally refers to a remedial response that eliminates or reduces an
exposure pathway without removing or treating the source.