In recent years, a large number of contaminated sites arose in the process of urbanization and industrial upgrading, which seriously threaten the environmental security. Since 1970s, the management and remediation of contaminated sites became an important research topic promoting the formation of technical standards and the development of integrated site management and decision-making system. According to the “Soil Pollution Prevention and Control Action Plan” issued by the State Council in 2016, the contaminated soil should be remediated at these sites.
The remediation of contaminated sites is a complex project including surveys, risk assessments, screenings of remediation technology and etc, where information management, multiple model applications and multi-attribute decision-making issues are involved. Decision-making assistance systems play an important role on contaminated site information management, pollutant risk assessment and restoration technology selection. The decision of contaminated site remediation technology is actually a multi-attribute decision-making process. Based on WebGIS and database technology, an online contaminated site remediation decision-making assistance system was designed and developed in this study. This system adopted the B/S mode so that all registered users could enjoy the online services such as data storage and management risk assessment, calculation models and geoprocessing without installing any client or configuring system environments. Furthermore, expert online consultation was also permitted for selecting the potential contaminated site restoration technologies. The main functions of the system include three aspects: 1) Contaminated site information management, including text information data, geospatial data, sampling point data, etc.; 2) Risk assessment and visualization of contaminated sites, where the risk assessment part includes the carcinogenic risk and non-carcinogenic risks of objective pollutants; 3) the selection of soil remediation technology for contaminated sites and on-line assessment of restoration techniques and programs. Finally, the developed decision-making assistance system was applied to the remediation of polluted site in an abandoned chemical factory as a case study. With this system, all related GIS information could be effectively managed in an integrated fashion, and the risk assessment as well as the remediation technology screening was effectively completed.
The system not only effectively manages contaminated site information, but also provides an auxiliary function for the preparation of contaminated site remediation technology plans. Additionally, the knowledge base of the system was open to public for the science communication purpose. In conclusion, the design and implementations of this decision-making assistance system is helpful to the promotion of the informatization and networking level of contaminated site management and remediation.