Explanation:

? Bioremediation is not only a process of removing the pollutant from the environment but also it an ecofriendly and more effective process.

? The pollutants can be removed or detoxified from the soil and water by the use of microorganism, known as bioremediation. The purpose of bioremediation is to make environment free from pollution with help of environmental friendly microbes. Bioremediation broadly can be divided in two category i.e In-situ bioremediation and ex-situ bioremediation.

? In situ bioremediation provide the treatment at contaminated sites and avoiding excavation and transport of contaminants, means there is no need to excavate the water or contaminated soil for remediation. This in-situ bioremediation further sub divided into following category.

? Bioventing: It is a technique to degrade any aerobically degradable compound. In bioventing the oxygen and nutrient like nitrogen and phosphorus is injected to the contaminated site. The distribution of these nutrient and oxygen in soil is dependent on soil texture. In bioventing enough oxygen is provided through low air flow rate for microbes. Bioventing is nothing but it is pumping of air into contaminated soil above the water table through well which sucked the air.

? Biosparging: In biosparging air is injected below the ground water under pressure to increase the concentration of oxygen. The oxygen is injected for microbial degradation of pollutant. Biosparging increase the aerobic degradation and volatilization. There must be control of pressure while injecting the oxygen at the contaminated site to prevent the transfer of volatile matter into the atmosphere.

? Bioagumentation: Microorganisms having specific metabolic capability are introduced to the contaminated site for enhancing the degradation of waste. ? Ex-Situ Bioremediation: The treatments are not given at site. In ex situ, the contaminated soil excavate and to treat it at another place. This can be further sub divided into following categories o Biopiling - It is a hybrid form of composting and land farming. The basic biopile system includes a treatment bed, an aeration system, an irrigation/nutrient system and a leachate collection system. o Landforming - In land forming make a sandwich layer of excavated soil between a clean soil and a clay and concrete. The clean soil at bottom and concrete layer should be the upper most layers. After this allow it for natural degradation. In it also provide oxygen, nutrition and moisture and pH should also maintain near the pH 7 by using lime. Land forming is useful mainly for pesticides. o Compositing: Compositing is a process in which microorganism degrades the waste at elevated temperature that is ranges from 55- 65.