Bioremediation of Chromium Contaminated and Harbor Dredged Soil

Abstract

Soil contamination is caused by the presence of manmade chemicals in the natural soil environment. It is often caused by some form of industrial activity, agricultural chemicals or the improper disposal of waste. The most common chemicals involved in soil pollution are petroleum hydrocarbons, pesticides and lead and other heavy metals. Heavy metals are among the major environmental pollutants and the accumulation of these metals is a great concern in agricultural production due to the toxic effects it has on crop growth. Remediation of soil is a challenging process but if done perfectly it can yield very good results. Firstly the physical and chemical properties of the soil are tested for understanding the properties of the soil. Test such as sieve analysis, liquid and plastic limit are done to understand the characteristics of the soil. The contaminants and their concentration in the soil can be identified using SEM ANALYSIS and EDAX. The soil is remediated using purpose which suits the nature of the soil. Remediation of soil can be done using either micro organism, chemicals, plants, by passing high voltage current or by other physical purposes. Use of micro organisms is one of the advanced methods of remediation. Micro organisms such as pseudomonas aeruginosa, pseudomonas alcaligenes, and pseudomonas hibisciola are used for remediating the heavy metals of the soil. The micro organisms are inoculated in the contaminated soil and tests such as pH, temperature, UV spectroscopy 620 nm are conducted to understand the effect of micro organisms on the soil. Atomic Absorption Spectroscopy is finally conducted for the 0th hour and 100th hour to understand the amount of heavy metal reduction in the soil samples.