This report is a planning tool which provides information on small water treatment systems. The content of this report is directed to the governing bodies responsible for the small water treatment systems so that they can better understand what is required of them by the National Interim Primary Drinking Water Regulations regarding treatment of their water and the related costs. It is directed to the water plant operator or city engineer to assist one in understanding what can be expected of various treatment processes with regard to meeting the maximum contaminant levels (MCL) specified in the regulations. Finally, the report is directed to consulting engineers to assist them in planning for new and/or improved water treatment systems. The report will provide the engineer with treatment techniques, design parameters and cost information in regard to meeting the various MCL's.