SCICHEM is a reactive non-steady-state plume dispersion model that can be used to calculate single and multi-source emissions downwind as well as short and long-range calculations. AQcast: SCICHEM uses the latest version and updates automatically with no user action required. AQcast will download and process all necessary terrain and meteorological data files appropriate for the user specified scenario and run SCICHEM. ESRI GIS shapefiles of facility buildings and fence lines can be uploaded and input into the model or drawn on the map provided in the user interface. Following the successful completion of SCICHEM, various plots and summary files are displayed on the AQcast: SCICHEM access portal, and a link to download all modeling files is provided.