Development of the Integrated Physicochemical-Biological Technology for Remediation of Heavy Metal Contaminated Soils.

Recently, agricultural food and crop safety has been awarded because of heavy metal pollution in agricultural field. Ministry of Environment (MOE) in Korea established maximum criteria level (MCL) of heavy metals (Cd and Pb) for total of 13 crops in 2010. Therefore, minimizing heavy metal transfer from soil to crops is key issue in Korea. The main objective of this study was to develop integrated physicochemical and biological technology for remediation of heavy metal contaminated agricultural field. Total of 504 experimental plots at the size of 1m(L) x 1m(W) x 1m(D) were constructed and integrated remediation technologies were applied randomly in both paddy and upland field. Representative physical treatments were soil cover and soil dressing and total of 5 chemical stabilization materials, lime, steel slag, zeolite, dolomite, and compost, were chosen. As biological treatment technologies, phytoremediation and microbial stabilization were adapted. Once integrated remediation technologies were applied in the field, heavy metal concentration of each plot was continuously monitored along with soil pH. The result showed that soil pH was increased from 6.5 as initial soil pH to 7.5 after integrated treatments were applied. This result can be assumed that chemical amendments play an important role to increase soil pH. Also, heavy metal concentration in each plot was decreased at the range of 30-60% for Cu, 25-79% for Pb, and 15-41% for Zn depending on treatments and agricultural fields for 32weeks monitoring periods. Integrated physicochemical and biological remediation technology can be adapted to heavy metal contaminated agricultural field and might have synergetic effect compared to single remediation technology.

 

 Keywords: Heavy metal, Agricultural field, Remediation, Integrated technologies