Hanford Site National Environmental Policy Act (NEPA) characterization. Revision 6

This sixth revision of the Hanford Site National Environmental Policy (NEPA) Characterization presents current environmental data regarding the Hanford Site and its immediate environs. This information is intended for use in preparing Site-related NEPA documentation. Chapter 4.0 summarizes up-to-date information on climate and meteorology, geology and hydrology, ecology, history and archaeology, socioeconomics, land use, and noise levels prepared by Pacific Northwest Laboratory (PNL) staff. More detailed data are available from reference sources cited or from the authors; Chapter 5.0 has been significantly updated from the fifth revision. It describes models, including their principal underlying assumptions, that are to be used in simulating realized or potential impacts from nuclear materials at the Hanford Site. Included are models of radionuclide transport in groundwater and atmospheric pathways, and of radiation dose to populations via all known pathways from known initial conditions; The updated Chapter 6.0 provides the preparer with the federal and state regulations, DOE orders and permits, and environmental standards directly applicable to the NEPA documents on the Hanford Site, following the structure of Chapter 4.0. No conclusions or recommendations are given in this report. Rather, it is a compilation of information on the Hanford Site environment that can be utilized directly by Site contractors. This information can also be used by any interested individual seeking baseline data on the Hanford Site and its past activities by which to evaluate projected activities and their impacts