The tasks performed in the Remedial Investigation/Feasibility Study (RI/FS) work plan for each Hanford Site operable unit must meet the requirements of the Comprehensive Environmental Response, Compensation, and Liability Act of 1980 (CERCLA) and the Hanford Federal Facility Agreement and Consent Order (Tri-Party Agreement, Ecology et. al 1992). An extensive amount of data will be generated in the evaluation and remediation of hazardous waste sites at the Site. The data must be of sufficient quality, as they will be used to evaluate the need, select the method(s), and support the full remediation of the waste sites as stipulated in the Tri-Party Agreement. In particular, a data management plan (DMP) is to be included in an RI/FS work plan for managing the technical data obtained during the characterization of an operable unit, as well as other data related to the study of the operable unit. Resource Conservation and Recovery Act of 1976 (RCRA) sites are involved in the operable unit. Thus, the data management activities for the operable unit should be applied consistently to RCRA sites in the operable unit as well. This DMP provides common direction for managing-the environmental technical data of all defined operable units at the Hanford Site during the RI/FS activities. Details specific to an operable unit will be included in the actual work plan of that operable unit.