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Executive SummaryContaminant transport is traditionally modeled in a two-phase system: a mobile aqueous phase and an immobile solid phase. Over the last 15 years, there has been an increasing awareness of a third, mobile solid phase. This mobile solid phase, or mobile colloids, are organic or inorganic submicron-sized particles that move with groundwater flow. When colloids are present, the net effect on radionuclide transport is that radionuclides can move faster through the system. It is not known whether mobile colloids exist in the subsurface environment of the Hanford Site. Furthermore, it is not known if mobile colloids would likely exist in a plume emanating from a Low Level Waste (LLW) disposal site. No attempt was made in this study to ascertain whether colloids would form. Instead, experiments and calculations were conducted to evaluate the likelihood that colloids, if formed, would remain in suspension and move through saturated and unsaturated sediments.The objectives of this study were to evaluate three aspects of colloid-facilitated transport of radionuclides as they specifically relate to the LLW Performance Assessment. These objectives were: 1) determine if the chemical conditions likely to exist in the near and far field of the proposed disposal site are prone to induce flocculation (settling of colloids from suspension) or dispersion of naturally occurring Hanford colloids, 2) identify the important mechanisms likely involved in the removal of colloids from a Hanford sediment, and 3) determine if colloids can move through unsaturated porous media.Mobile colloid formation is commonly described as a three-step process: genesis, stabilization, and transport. Colloid genesis describes how the micron-sized particles are formed in groundwater. Stabilization describes how the colloids are brought into suspension, which is a function of the colloid and groundwater chemical composition and water flow (kinetic) forces. Transport describes how the suspended colloid move through the porous media or are retained by the porous media by physical forces (such as diffusion, straining, or gravitation settling) or physicochemical attraction of the colloid to the matrix.As the second step in mobile colloid formation indicates, colloids must remain in suspension, i.e., not flocculate, in order to be transported with groundwater flow. A series of batch experiments was conducted to identify the chemical conditions where dispersion and flocculation (settling out of suspension) of Hanford sediment colloids (

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In this article I compare a robotic gamelan sound installation (the gamelatron) and traditional gamelan, as performed in the American gamelan subculture, in order to specify the concept of atmosphere for use within ethnomusicology. I argue that at the level of affect the gamelatron and gamelan afford similar experiences that I call “atmospheres of felt-relation.” At the level of comprehension they are registered as divergent because of their differential alignment to several discursive binaries: live/recorded, human/machine, individual/group, subject/object and body/prosthesis.

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