This report contains Contaminant Information Sheets for 561 chemical contaminants on the Preliminary Contaminant Candidate List (PCCL 3). These sheets summarize information about the chemicals that were considered during the analysis for the development of the final third Contaminant Candidate List (CCL 3). The sheets are in alphabetical order. The first 106 Information Sheets are for the chemicals on the final CCL 3. (Note: there are 104 chemical entries listed in the Federal Register Notice for the final CCL 3; cyanotoxins are listed as a group. In this file, there are information sheets on three individual cyanotoxins that were evaluated in the CCL 3 process (Anatoxin-a, Cylindrospermopsin, and Microcystin-LR)).