Operable Unit (OU)

A discrete portion of a DOE installation identified as a group of release sites placed together for the purpose of remediation as a single project. OUs may represent geographical portions of an installation, or they may represent a specific installation problem, such as surface/subsurface groundwater contamination. Cleanup of an installation may be divided into a number of OUs, depending on the complexity of the problems associated with the installation. An OU may represent all or part of discrete locations such as Waste Area Groups (WAGs) and Solid Waste Management Units (SWMUs). OUs usually contain more than one release site, may be in close geographic proximity to other OUs, and may exhibit similar waste characteristics and types of releases. Release sites do not have to be contiguous to be included in a specific OU.