Growing awareness of geoenvironmental hazards has made clear the need to develop better technical knowledge of environmental issues. We are thus studying how to remediate soil and groundwater contaminated by heavy metals and organic chemical substances in natural and man-made disasters. Remediation technology includes containment and risk assessment of contaminated land, with permeable reactive barriers (PRBs) and monitored natural attenuation (MNA) presented as the passive and cost-effective techniques. A case study to assess the effectiveness of a containment facility as a remedial technique in reducing human health risks was introduced. Numerical analyzed results confirm that this significantly reduces potential human health risks from land contaminated by polychlorinated biphenyls (PCB) and dioxin. Risk assessment based on in situ monitored data indicated that no significant health risks were induced. The important projected role of the geoenvironment is developing a sustainable contamination-free society.