The project evaluated the economic uncertainties for CO2 flooding of the Belridge Diatomite. Part of the project involved identification and demonstration of several systems to monitor CO2 flood movement within the reservoir and to image the CO2 migration. Implementation of the CO2 flood at Lost Hills field resulted in installation of a four- pattern, 2.5 acre pilot, upgrading facilities, reworking several injection wells and drilling two new injection wells, and construction of CO2 facilities and lines, and setting up a CO2 monitoring system. All construction was completed and CO2 injection began in August 2000. The study evaluated how injection of a very low viscosity gas differed from injection of water into the diatomite in terms of fracture azimuth, injectivity, and areal and vertical sweep.