This study focuses on laboratory studies with related analytical and numerical models, as well as work with operators for field tests to enhance our understanding of and capabilities for more efficient enhanced oil recovery (EOR). Much of the work has been performed at reservoir conditions. This includes a bubble chamber and several core flood apparatus developed or modified to measure interfacial tension (IFT), critical micelle concentration (CMC), foam durability, surfactant sorption at reservoir conditions, and pressure and temperature effects on foam systems.Carbon dioxide and N{sub 2} systems have been considered, under both miscible and immiscible conditions. The injection of CO2 into brine-saturated sandstone and carbonate core results in brine saturation reduction in the range of 62 to 82% brine in the tests presented in this paper. In each test, over 90% of the reduction occurred with less than 0.5 PV of CO{sub 2} injected, with very little additional brine production after 0.5 PV of CO{sub 2} injected. Adsorption of all considered surfactant is a significant problem. Most of the effect is reversible, but the amount required for foaming is large in terms of volume and cost for all considered surfactants. Some foams increase resistance to the value beyond what is …

A letter report issued by the Government Accountability Office with an abstract that begins "This report is GAO's sixth annual assessment of selected weapon programs. Since 2000, the Department of Defense (DOD) has roughly doubled its planned investment in new systems from $790 billion to $1.6 trillion in 2007, but acquisition outcomes in terms of cost and schedule have not improved. Total acquisition costs for major defense programs in the fiscal year 2007 portfolio have increased 26 percent from first estimates, compared with 6 percent in 2000. Programs have also often failed to deliver capabilities when promised. DOD's acquisition outcomes appear increasingly suboptimal, a condition that needs to be corrected given the pressures faced by the department from other military and major nondiscretionary government demands. This report provides congressional and DOD decision makers with an independent, knowledge-based assessment of defense programs, identifying potential risks when a program's projected attainment of knowledge diverges from best practices. The programs assessed--most of which are considered major acquisitions by DOD--were selected using several factors: high dollar value, acquisition stage, and congressional interest. This report also highlights overall trends in DOD acquisition outcomes and issues raised by the cumulative experience of individual programs. GAO updates …