HSEQ
FEATURE
WASTE MANAGEMENT
Management of oil
contaminated sites: Is
it attainable in Africa?
T
By Daniel Kiige
Principal
Consultant
Hiagro Leeway (K)
Ltd.
E-mail: dkiige@
hiagroleeway.com
Website: www.
hiagroleeway.com
(Consultants in
Environmental
Impact
Assessments
& Audits,
Environmental
Management
& Planning and
Occupational
Health & Safety)
he Oil sector is one of the largest and
most profitable industries in the world.
Last year, in Fortune magazine’s annual
rank of the 500 largest companies in the
world, oil companies held seven of the top
ten positions. The products of oil refineries
are extremely useful and have become necessities in modern society. However, when oil
is improperly handled, it can be extremely
hazardous to the environment and dangerous to human health. Oil spills and careless
waste management of toxic byproducts from
the refining process lead to extreme health
problems for humans and animals and
contaminates the environment. Oil spills
are often unintentional and in most cases
difficult to prevent. On the other hand, careless waste management is controllable, but
sometimes oil companies choose not to take
preventive measures because it may be costly
and time-consuming to do so.
To limit environmental impacts, governments need to enforce tighter restrictions
on oil waste management and, more importantly, any sites containing oil pollution need
immediate remediation.
Remediation has not been strictly enforced
by governments in Africa. Since most countries lack strict oil development regulations
and enforcement, the polluting effects of careless oil development are far more apparent.
However, most oil companies in Africa are
multi-nationals and are internationally pressured by their mother companies to enhance
environmental sustainability in the oil sector.
What is remediation?
In this context, it is the removal of pollutant/
contaminant (hydrocarbons) from an environmental media – soil, air or water.
18
Process of remediation
1. Site Assessment - this is the determination of the extent of pollution or contamination. It will help you in determining the
remediation technique to apply.
2. Choosing a remediation technique.
Cleaning contaminated soil is usually a
lengthy and intensive process. A couple of
factors determine the type of remediation
technique used at a specific site. The first
factor is the type of contamination that
is present. Soil contamination and water
contamination can require different remedial
techniques. Furthermore, it is important to
discern whether the problem strictly relates
to surface water contamination or if the
pollutants have seeped into the groundwater.
Also, the weight and other physical properties
of the contaminant greatly affect the technique chosen. The second factor in choosing
a remediation technique is the location of the
contaminated site. This will greatly affect the
type of remediation chosen because remediation techniques are only feasible if the site can
be reached by the needed equipment. If the
contaminated area is easily accessed by
remediation technology, an onsite technique
may be preformed. If the site is hard to reach,
offsite remediation techniques must be used
and the contaminants must be transported to
another location.
A combination of methods may be appropriate if effective techniques can be identified
and the decision is made to implement them.
For example, some mechanical tilling may be
necessary to enhance biodegradation.
The most appropriate technique is obtained
through evaluation of these methods against
factors for effectiveness, implementability
and operations.
.
Lubezine Magazine | January-March 2012