The Tank Waste Remediation System (TWRS) includes many activities required to remediate the radioactive waste stored in underground waste storage tanks. These activities include routine monitoring of the waste, facilities maintenance, upgrades to existing equipment, and installation of new equipment necessary to manage, retrieve, process, and dispose of the waste. In order to ensure that these multiple activities are integrated, cost effective, and necessary, a sound technical baseline is required from which all activities can be traced and measured. The process by which this technical baseline is developed will consist of the identification of functions, requirements, architecture, and test (FRAT) methodology. This process must be completed for TWRS to a level that provides the technical basis for all facility/system/component maintenance, upgrades, or new equipment installation.