This article provides a preview of the radionuclide regulations. While the regulations may be changed up until the rule is formally proposed, this information reflects current USEPA thinking on the rule's technical content. Presented are: background information, scope of the rule, health effects information, maximum contaminant levels, analytical methods, and best available technologies, monitoring, compliance determinations, vulnerability assessments, and administrative details. Some guidance for preparing for the new rule is given. Includes 3 references, tables.