Study On Survey And Evaluation Of Heavy Metal And Polycyclic Aromatic Hydrocarbons In The Electrical Waste Contaminated Site

The inappropriate disposal of electronic waste could result in a large number of waste gas, waste water, and waste residue with toxic and harmful emissions. This is the main source of environmental pollution in the electronic waste dismantling area. In this paper, we choose a typical electronic dismantling area in the southern China as the research object. The soil type is sediments of the river and soil in farmland. The main purpose is to investigate and evaluate the pollution of Cu, Ni, Cd, Pb, and polycyclic aromatic hydrocarbons (PAHs).According to the analyse and evaluation of heavy metals of the soil in the farmland, about 10% of soil in the farmland has been moderately or heavily polluted by the heavy metals, especially Cu, Ni, and Cd. The soil of farmland close to the acid bath of heavy metals site, is subjected to very serious pollution of acid and heavy metals. The combination effect of acidification and heavy metal pollution make the high percent of activated heavy metal in the soil. Overall, the pollution of PAHs is not very serious in the farmland soil. With the depth of 0~10 cm, the pollution is obvious within 5m of the acid bath area. And when the depth is more than 10cm, the concentration of PAHs decreases obviously.The concentration of Cu in river sediment is up to 3000mg/kg in the most polluted area, because many small acid bath workshop is close to the bank of the river. The waste water and residue are discharged directly into the river and the waste could transmit into the river sediment. The concentration of heavy metal in the confluence of the dry streams and tributaries is very high. This is due to the concentration of tributary and acid bath workshop along the river. The PAHs concentration in the sediments of the tributary is 11 times more than the CK area, and the pollution is very serious. The source of pollutant is also very complicated, such as woods, coal, cracking of the petroleum and tail gas of the cars.The survey in the electrical waste disposal area shows that the pollution by heavy metal and PAHs in the soil and river sediment is heavier than the other area in where there is no electrical waste dismantling activities.