Bioremediation is the treatment of contaminated material involving the natural degradation of contaminants by bacteria. This process is particularly suitable for hydrocarbon contaminants such as petrol and diesel range organics. The rate of decomposition can be greatly increased by the addition of nutrients and by controlling moisture, temperature, oxygen and pH levels.
Biopiles are engineered, bunded and covered systems. Depending on the contaminant type and level, various engineering methods are used to enhance the growth and viability of the microbes. Addition of warm air (providing warmth and oxygen), removal / addition of water and modification of the pH levels are all methods used to increase the microbial action and therefore enhance remediation.
Windrows are bunded piles of material, shaped to allow the maximum amount of oxygen into the pile. They require regular turning but can prove effective on certain sites.
Where it is uneconomical or not possible to remove material for bioremediation, in-situ methods are available. These methods are implemented through boreholes, forming trenches or in-situ bio piles and can prove very effective in the right circumstances.