ABSTRACT
Soil contamination occurs every moment of our life. It happens when a hazardous solid or liquid substance mixes with the naturally occurring soil. In most cases, the contaminants are attached to the soil either physically or chemically. Sometimes they are trapped in between the particles of the soil. The contaminants usually come in contact with the soil by one of two ways; they are either spilled into the soil or are buried directly. One of the most common substances spilled into soil is oil (Figure 16.1). It often gets into the soil by leaking from tanks, being spilled during the transportation process, during loading/unloading, and leaks from pipelines. The severity of the contamination depends on the type of oil involved. The heavier the oil, the slower it is able to spread. However, if light oil is involved, it is able to seep through the top soil quite quickly. It then continues to move quickly through the layers of soil. The faster the cleanup operator responds to the spill/leak, the better the chance of stopping the contamination from spreading to the surrounding areas. Biological
16.1 Introduction .......................................................................................................................... 327 16.2 Type of Bioremediation ........................................................................................................ 329
16.2.1 Intrinsic In Situ Bioremediation ............................................................................... 329 16.2.2 Engineered In Situ Bioremediation .......................................................................... 330 16.2.3 Engineered Ex Situ Bioremediation ......................................................................... 334
16.3 Designing a Bioremediation Project ..................................................................................... 337 16.3.1 Site and Soil Characterization .................................................................................. 337
16.3.1.1 Contaminants Characteristics .................................................................... 337 16.3.1.2 Physicochemical Environmental Characteristics ...................................... 339
16.3.2 Selecting Remediation Method and Technology ...................................................... 339 16.3.3 Treatability Studies ...................................................................................................340
