Methodelogy And Case Study Of Enacting Benchmarks For Remediation Of Contaminated Soils And Its Effectivity Assessment

With the rapid development of remediation technology for contaminated soils in China in recent years, the remediation standard has become a choke point to judge the effectivity of the remediation of the contaminated soils. In this paper, we studied the remediation standards of the other countries and analyzed the disadvantages of Environmental quality standard for soils in China. It was emphasized that the choice of contaminations, rules of detection, classified contaminated soils, protection of groundwater and toxicological risk assessments should be fully considered in the enactment of remediation standards. We studied the Pb and acetochlor which were pollutions existed widely in northeastern China. It is the first attempt to enactment a remediation standards and assessment about remedial soil in area.By testing the inhibition of seed germination and root elongation of crops (Chinese cabbage (Brassica pekimensis), soybean (Glycine max), wheat (Triticum aestivum)), by test of the food quality standard and a maximum acceptable damage of wheat (Triticum aestivum), by testing the toxicological effects on earthworms, by testing the physiological mechanisms in wheat that stressed by Pb and acetochlor, and by testing the transfer of Pb in soil and by test the effect of soil enzyme activities, we got the remediation of standard of Pb and acetochlor were 3.98~793 mg·kg-1 and 0.4~12 mg·kg-1。They are the strictest standard for agriculture soil. There is no distinct effect on all the part of the soil system.On the basis of investigation of heavy metals pollution in the Shenyang smeltery site, we assessed the human health risk by using the United States Environmental Protection Agency methodologies for human health risk assessment. For the defined future land use patterns, the industrial (I) and recreational (II) exposure scenarios were assumed and evaluated. The results of the human health risk assessment indicated that the soil was serious pollution and the potential health risks at Shenyang smeltery soil were mainly associated with the exposure to copper (industrial and recreational scenarios). The risk-based remedial goals calculated under the industrial scenario were lower than environment quality risk assessment criteria for soil at manufacturing facilities of China. The human health risk assessment only can not completely express the potential risk of soil. But the test of seed germination, crop growth, and the toxicological effects on earthworms can demonstrate the holistic characteristic of soil quality.