Supercritical CO2 viscosified by two orders of magnitude using a commercial silicon polymer and toluene as cosolvent, was used in the laboratory corefloods and the results reported previously. More corefloods in Berea cores with pressure taps along the core were conducted to investigate the transport of chemicals in the core. In an attempt to reduce the chemical costs, different silicon polymers and hydrocarbon cosolvents were tried. The effect of methane on the solubility of polymers was also investigated. Scoping economic runs were made by modifying an actual economic analysis of a field CO2 project, which showed that chemical costs have to be reduced significantly for the process to be economic.