Treating and revitalizing Superfund sites can be a time consuming and
costly business. However, the flooding in Texas caused by Hurricane Harvey, and the subsequent extreme weather events in September, shows that
ignoring them is not an option if we are to safeguard the surrounding population. Storm damage – and the resulting threat of the rising waters stirring
and releasing dangerous sediment – mean it’s time to take advantage of
new systems which mean cost-effective remediation is no longer out of
reach, says Ryan O’Loan from waste management specialist CDEnviro.
Land is plentiful in the USA and treating brownfield land can seem a low
priority when there are easier and cheaper development opportunities
available. Surely the pollutants contained in the Superfund sites are locked
away underground, so what is there to worry about? Even if that was true
and there wasn’t the risk of contaminants leaching into waterways,
surrounding land or the air, the increasing incidents of extreme weather
and potential to release pollutants more widely have brought the issue into
The contaminants left behind from industrial activity, including mining,
manufacturing orpetrochemical processes include heavy metals, such as
cadmium, chromium, copper, leadand zinc. In large concentrations, they
are likely to be hazardous to health and can’t berelied on to stay hidden out
of harm’s way.
The health risks range from the relatively minor physical symptoms, such
as skin rashes, tolife-threatening diseases. People can be affected by the
pollution through direct contact,including ingestion through the food chain
or by toxins leaching into the water table. Anadded danger of leaving land
untreated is the risk of inhalation of airborne contaminants such as anthrax
spores or small pox.
Exposure of these materials through floods mean the danger becomes more
immediate, but even without extreme weather events there’s a danger of
long-term contamination affecting generations.
Solutions are available :
It doesn’t have to be that way. Systems are now available that can treat
contaminated soil, making the land suitable for safe reuse.
One of the reasons people have been reluctant to invest in remediating
these sites in the past is the time and expense involved, largely due to the
presence of heavy metals and difficult to manage large rocks.
Both are treatable, but traditionally it’s taken different machinery and processes adding to the time and expense required to bring the land back into
use. Now though that problem has been solved.
Systems are available that can
treat both issues simultaneously, making remediation a much
more practical and cost-effective solution. Using a combination of high-tech screening,
sorting and scrubbing approaches, the material is broken
up, cleaned and recovered all in
one go. The combined approach
speeds up projects saving time
Systems can be customized
for the likely contaminants on
a site and the space there is to
work in. Ideally the systems
will have the option of between being modular and portable when they’re
required on several sites, or fixed turnkey installations for longer-term
projects, where you just want to turn them on and go. This gives the operator the required flexibility to choose the appropriate system.
For heavy metals, material scrubbing and recovery processes are used. Tertiary water treatment also allows the reuse of water that becomes heavily
contaminated in the recovery process.
These efficient mechanical washing and scrubbing systems are not reliant
on chemicals as has been the case in the past. They can now remove hydrocarbons from the surface of the contaminants and then isolate and remove
them from the washing water afterwards in a chemical-free way.
Traditionally, large machinery, such as a heavy-duty excavator mounted breaker has been required to deal with the hard rock as it can be big,
abrasive and difficult to process. These machines aren’t cheap, and the
processing takes its toll resulting in downtime and expensive repairs.
New systems avoid this, which can mean huge savings on operating costs
and potential environmental issues. The machines can also deal with
organic matter, and enable clean material, such as sand and gravel to be
recovered and recycled for use in construction.
Weather the storm When storms and floods hit they bring devastation
to people and property. By tackling Superfund sites, we have the opportu-
nity to ensure that the immediate impact is not compounded by unneces-
sary widespread contamination. www.cdenviro.com
Circle 127 on Card or http://pen.hotims.com/69825-127
Highlight by Recent Hurricanes