Hazardous waste sites: can lead
to groundwater contamination if
there are drums or other containers
Chemicals: can include chemical
products used on lawns and farm
fields to kill weeds and insects
and to fertilise plants, as well as
other products used in homes and
businesses. When it rains, these
chemicals can seep into the ground
and eventually into the water supply
under the ground. In countries where
it snows, road salts are used to melt
ice on roads to keep car tyres from
losing traction and sliding. When the
ice melts, the salt gets washed off the
roads and eventually ends up in the
water.
Atmospheric contaminants: can also
be a source of contamination. Since
groundwater is part of the hydrologic
cycle, contaminants in other parts of
the cycle, such as the atmosphere
or bodies of surface water, can
eventually be transferred into our
groundwater supplies. u
W
hile beneath the surface
lie vast aquifers that hold
millions of litres of water, all
groundwater is not the same and vital
treatment of this water is required,
as is cutting edge filtration systems
to make it potable. The demand for
these technologies, innovations,
and products is on the increase as a
result of the demand for an alternative
water source.
Over time, water filtration
technology has evolved
from the simple cloth
sieving method to acoustics
and nanotube technology,
offering a variety of options
from which to choose in
the ongoing search to make
water potable.
Septic systems: are designed to drain
away human waste underground at a
slow, harmless rate and are normally
part of an on-site wastewater disposal
system used by homes, offices, or
other buildings that are not connected
to a city sewer system. However,
an improperly designed, located,
constructed, or maintained septic
system can leak bacteria, viruses,
household chemicals, and other
contaminants into the groundwater
system.
Landfills: are the places that our
garbage is taken to be buried. While
landfills are supposed to have a
protective bottom layer to prevent
contaminants from getting into
the water, if there is no layer or if
it is cracked, contaminants from
the landfill (car battery acid, paint,
household cleaners, and the like) can
make their way through the soil, down
into the groundwater.
Nanotechnology
A few years ago, Nano Sun of
Singapore’s Nanyang Technological
University developed a multifunctional
water filtration membrane that uses
titanium dioxide nanotechnology
instead of the usual polymer-based
water filtration membranes. It kills
bacteria and breaks down organic
compounds using the ultraviolet rays
of the sun. In addition, it claims to be
environmentally friendly as it reduces
biofouling or the accumulation of
microorganisms that usually grow on
moist surfaces.
Acoustics nanotube
technology
Originally developed to purify
wastewater for reuse aboard
the International Space Station,
innovators at NASA’s Johnson Space
Centre developed a filtration system
to eliminate contaminants from
water supplies. The innovation is
applicable to numerous applications
where there is a need to collect
potable, medical-grade water from
a contaminated water supply. The
exceptional aspect of the technology
is its use of acoustics rather than
pressure to drive water through
small-diameter carbon nanotubes.
The invention requires less power
Water Sewage & Effluent July/August 2017
27
Storage tanks: may be above or below
ground and may contain residue
petrol, oil, chemicals, or other types of
liquids. Over time, tanks can corrode,
crack, and develop leaks. If the
contaminants leak out and get into the
groundwater, serious contamination
can occur.
Potable (filtration)
possibilities
technology
Potential sources of
groundwater contamination
lying around that contain hazardous
materials. If there is a leak, these
contaminants can eventually make
their way down through the soil and
seep into the groundwater.
Diseases such as hepatitis and
dysentery may be caused by
contamination from septic tank waste
leaking into a groundwater source,
while poisoning may be caused by
toxins that have leached into well
water supplies. Not only humans but
wildlife too can be harmed by polluted
groundwater, and other lasting
effects, including certain types of
cancer, may also result from exposure
to contaminated water.