Soil/Sediment Adsorption Constant Program uses the SMILES notation structural input to calculate the soil or sediment adsorption coefficient (Koc) from a correlation of the molecular connectivity indices and correction factors for certain chemical classes. This method was developed by the U.S. Environmental Protection Agency's (EPA) Office of Toxic Substances and is now available for use on any IBM (R) or IBM-compatible computer with 240K RAM. This powerful, user-friendly program provides reliable data that will benefit any environmental chemist or regulator, chemical companies, and analytical labs.