Subsurface simulation model continues the project for the development of the underground environment analysis model for contaminated sites in 2018, having completed the development of the module coupling with subsurface flow, thermal and chemical transport in our core model which is called HYDROGEOCHEM (i.e. HGC). A user-friendly operation interface has been built as well, playing a key supporting role in management and remediation practices of polluted sites. In order to make the subsurface simulation models more suitable for groundwater contaminated sites in Taiwan, four major work items were carried out : (1) Supplement the readability of the guidelines (draft) for the establishment of the hydrogeological conceptual model and the case analysis of domestic sites.(2) Improving the functionality of the modules in the subsurface simulation model and build 10 scenario templates. (3) To facilitate the user's operational needs, the user interface for hydrogeological information and the user interface for the fast assessment tool module are added, and the user interface of the newly added core module function has been revised. (4) Selection of one accelerated decommissioning site as a demonstration case to establish working hypotheses and arrange to carry out supplementary investigation work, providing feedback to guidelines based on the investigation results and establishing three remediation techniques to preliminarily evaluate simulation results. Another target of this project is to promote the Taiwan Subsurface Environmental Simulation Model Plateform (i.e. TWESMP) including conducting 14 interviews with model-concerned users during the project period. Based on a variety of users’ needs, 3 sessions of primary training course and 2 sessions of advanced training courses were conducted. Moreover, 4 sessions of seminar were held for model simulation according to the results of the verification and evaluation of a number of domestic sites established by TWESMP developed in this project. With concerns of the high professionality of model usage、evaluation and examination, it is recommended to assess the need of establishing a third-party dedicated unit to provide consulting review and services of educational promotion.