| Atrazine was widely used in the world since 1959 when it was put into trade. Atrazine has a good solubility in soil, so it easily migrates to deep layer or transported to the surface water or groundwater by the river. It has a long lasting time in the above circumstance and is hard to degrade. Up to now, our limited groundwater is seriously contaminated by atrazine. Atrazine is one of Endocrine-disrupting chemicals (EDCs), which is associated with hermaphroditism, resulting in dysgenesis or cause cancer in human and wild creatures and so on. It was reported that frogs were demasculinized after being exposed to atrazine at low levels of 0.1 parts per billion. The endocrine-disrupting effects of atrazine are not only restricted to frogs. Atrazine reduced olfactory-mediated endocrine functions in salmon observed in polluted water. And it was proved that it might inhibit testosterone production in prepubertal rats. Atrazine may endanger the health of human conveyed by food chain, and it may cause serious health problems. Studies show that atrazine causes tumors and cancer, including breast, ovarian, and uterine cancer, which affect parts of the body that directly connect to the hormone system, as well as leukemia and lymphoma. In consequence, those effect on reproductive systems and normal growth processes are devastating.Research on remediation of groundwater contaminated by atrazine not only can insure the safety circumstance by obliterating pollution cases and improve our sustainable development of our social economy, but also can enhance the competitiveness of our agricultural products in world trade.In last decades, the developed western countries used the traditional pump and treat out situ methods to treat contaminated groundwater. These methods can only control the polluting source (area), and it cost extremely high to maintain the process and has no function on Non-Aqueous Phase Liquids, so it has been replaced by the in situ remediation methods in recent years.Biodegradation is a very promising clear method for remediation with low cost and high effect. And it is meaningful in removal and remediation of the soil and water contaminated by organic polluters. It has many advantages such as economical, effective, and its end products have no secondary contamination to environment. But according to the in situ attenuation of groundwater, the environmental conditions are so complex that the microbes' large population induced may block the apeture or the added electron acceptor has no effect on the original or added microbes, which lead to the instable and unideal results. And these disadvantages make it barely used to practical works.Permeable reactive barrier technology(PRB)has newly developed as a promising in situ remediation method of groundwater. It was invented and endowed a monopoly by Waterloo University, Canada. The principle is that polluters can be degraded, absorbed or precipitated by the chemical reaction such as oxidation-reduction reaction, and physical or microbial reactions. This method has many advantages such as low cost, simple and practical, strong persistence in application period. But it also has many defects, for example, the militated of side reaction and erosion of iron, the coated surface by precipitation of metal iron, which may detract the reaction activity of iron. And the reaction principle makes it impossible to degrade low oxide matters etc.The study refers to the principle of PRB in situ remediation technology and the advantages of the bioremediation technology, we hope to prepare a combined reactive barrier used both microbes and chemical reactive materials in order to remedy the groundwater contaminated by atrazine and found a new effective method for in situ remediation. First we devised a chemical reactive barrier (CRB), using zerovalent iron as major reaction material and adsorbent added as subsidiary degradation substance. The experiment results suggest that the CRB using cinder as subsidiary adsorbent has the most effective degradation rat...
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