Every other year, Section 304(m) of the Clean Water Act requires EPA to publish a plan establishing a schedule for the annual review and revision of effluent guidelines required by Section 304(b). Section 304(m) also requires EPA to take public comment on its plan prior to issuing a final plan. EPA published the latest biennial plan, the 2004 effluent guidelines program plan ('2004 Plan'), on September 2, 2004 (69 FR 53705). EPA selected the Steam Electric Point Source Category (40 CFR 423) for detailed investigation because it ranked second in terms of toxic and non-conventional toxic-weighted discharges in the 2005 annual review. During the development of the 2004 Plan, EPA identified data gaps and issues that may affect the Agency's estimate of the potential hazards caused by discharges from steam electric facilities. To fill these gaps, EPA is currently collecting information on the wastewater characteristics and treatment technologies used at facilities in the steam electric point source category, including electric utilities and nonutilities that use fossil fuels or nuclear fuel to generate electricity for distribution in commerce. As part of the detailed study, EPA will also investigate data on facilities that are not currently regulated under Part 423 but that use a steam cycle to generate electricity. EPA will evaluate whether the point source category should be revised to include these facilities. This report presents the preliminary results of EPA's evaluation and outlines the additional data collection that will be conducted for the development of the next biennial plan ('2006 Plan'). The report is organized into the following sections: Section 2.0 summarizes the existing regulations for this industry; Section 3.0 discusses the data sources used in this profile; Section 4.0 presents a profile of the industry; Section 5.0 discusses wastewater characteristics; Section 6.0 discusses the additional information needs and next steps in the detailed review; and Section 7.0 presents the references used to date for the detailed study.