*3.3.3 O2 availability and moisture content*

The availability of oxygen is a very important factor also, as it ensures the oxidative and reducing environment in both soil and water environment. The nature of soil affects the aeration of the bioremediating site. Soil rich in sand and gravel content helps to retain moisture as well as aerate the soil well. More heavy the clay form or soil rich in organic content reduce the availability of oxygen and thereby inhibiting the functioning of microbes.
