A four-year multidisciplinary study released in 2004 concluded that carbon dioxide - a greenhouse gas - can be stored safely underground in geological formations such as the Weyburn oil fields in southeastern Saskatchewan. The Petroleum Technology Research Centre (PTRC) in Regina conducted the study under the auspices of the International Energy Agency Greenhouse Gas (IEA GHG) Research and Development Programme and in close collaboration with EnCana Corporation of Calgary, which operates the 50-year-old Weyburn oil field. This was the first large-scale study ever conducted of geological storage of carbon dioxide in a partially depleted oil field. The Weyburn oil field was selected for the study because detailed geological records and core samples, as well as almost 50 years of production history, were readily available; some 380 million barrels of oil have been produced from the field since it was discovered in 1954.
About 5 million tonnes of carbon dioxide were stored in the Weyburn oil field over the life of the study - the equivalent to taking about one million cars off the road for one year. The carbon dioxide was supplied for the experiment via a 325-km pipeline from the Dakota Gasification Company's coal-gasification plant at Beulah, North Dakota. During the study, researchers conducted a long-term risk assessment, completed geological and seismic studies, matched reservoir modeling against actual results, and performed frequent sampling to understand chemical reactions occurring in the reservoir. Utilizing seismic equipment, they were able to “see” the carbon dioxide mix with oil and follow the flow through the ground into nearby pump jacks. The $40 million funding for the Weyburn project came from Natural Resources Canada, the United States Department of Energy, Saskatchewan Industry and Resources, Alberta Energy Research Institute, and the European community. Altogether, the project involved 24 research and consulting organizations in Canada, the United States, and Europe.