Bioremediation is defined as the process whereby organic wastes are biologically degraded under
controlled conditions to an innocuous state, or to levels below concentration limits established by regulatory
Living organisms like bacteria, fungi or plants are utilized for bioremediation.
There are two types of bioremediation strategies involved - In-situ and ex-situ.
In-situ bioremediation uses techniques like bioventing, biosparging and bioaugmentation to treat soil or groundwater at their site of occurance itself. Ex-situ bioremediation involves the removal of the contaminated water or soil from the site and uses techniques like landfarming, composting, biopiles and bioreactors.
With all these clean up strategies, bioremediation has several advantages over other clean up procedures. A few of the many are:
a) Bioremediation is a natural process with less side effects than other processes which involves the usage of harmful chemicals.
b) Very less amount of microbes is needed to be added to the waste to be degraded. They multiply in large numbers utilizing the nutrients. This is very unlike clean up strategies using chemicals, the quantity of which is proportional to the quantity of contaminants.
c) The byproducts formed are far less toxic or even harmless residues like carbon dioxide, water and cell biomass. Many other clean up procedures produce byproducts that require further treatments or methods of elimination.
d) It is useful for the complete degradation of a wide variety of hazardous contaminants which eliminates future liability of their disposal.
e) In-situ bioremediation achieves a greater advantage of degrading the contaminants without them being transported to other sites. This helps in warding off potential threats to human health and environment that can arise during transportation. It also prevents the spread of contamination from one realm to other. eg. from water to soil to air etc.
f) Bioremediation is a very cheap process as compared to other clean up strategies which are much expensive. The main thing of consideration is that the contaminants must be biodegradable.