This report documents the activities performed and the results obtained from the arsenic removal treatment technology demonstration project at the Geneseo Hills Subdivision in Geneseo, IL. The main objective of the project was to evaluate the effectiveness of AdEdge Technologies (AdEdges) AD-33 adsorptive media (AM) system in removing arsenic to meet the new arsenic maximum contaminant level (MCL) of 10 ig/L. Additionally, this project evaluated (1) the reliability of the treatment system, (2) the required system operation and maintenance (O&M) and operator skill levels, and (3) the capital and O&M cost of the technology. The project also characterized the water in the distribution system and process residuals produced by the treatment process. The types of data collected included system operation, water quality (both across the treatment train and in the distribution system), process residuals, and capital and O&M cost. The water system at the Geneseo Hills Subdivision was supplied primarily by one well, i.e., Well No. 5, to meet an average daily demand of 40,600 gal/day (gpd). The well water contained 19.6 ig/L (on average) of total arsenic (with approximately 73% existing as soluble As(III)), 554 ig/L (on average) of total iron (with 65% existing as soluble iron), and 8.0 ig/L (on average) of total manganese (with 100% existing as soluble manganese). The water also contained 1.3 mg/L (on average) of ammonia (as N) and 1.9 mg/L (on average) of total organic carbon (TOC).