A Web-based Simulation System for Transport and Retention of Dissolved Contaminants in Soil

The movement of contaminants through the soil matrix is primarily a liquid phase process in which the chemical partitions between sorbed and dissolved phases. These phenomena have been modeled extensively and several computer models were developed. The use of those computer programs requires installation of the software in the users machine. Usually, post-processing of the numerical output provided by the software is required. In this paper, a web-based simulation environment for retention and transport of dissolved organic and inorganic compounds in soils is presented. The system was developed using Java and is based on the Multi-reaction Transport Model of heavy metals in soil. The mathematical and numerical formulation of the model is briefly sketched. The core computing components of the simulation environment were written in C or fortran for their computational efficiency. The emerging Java Native Interface (JNI) technique and the Swing interface were used to design a user-friendly simulator. Java security problems (due to the use of applets calling native libraries) are discussed and a solution to avoid security restrictions is provided. The simulation system provides interactive user control and real time visualization through standard web browsers. The Java-based simulation code was used to analyze a hypothetical soil contamination problem. The almost instantaneous visualization of results provided by the Java-based interface resulted in efficient and easy analyses. Although a performance comparison was not in mind, the evaluation of the same scenario using the original fortran code took three times as much total time (program run, evaluation of results and post-processing) as that using the Java simulation system