A report of  leaks above the project was released in January 2011 by an advocacy group on behalf of owners of land above the project. They reported ponds fizzing with bubbles, dead animals found near those ponds, sounds of explosions which they attributed to gas blowing out holes in the walls of a quarry. The report said that carbon dioxide levels in the soil averaged about 23,000 parts per million, several times higher than is normal for the area. "The ... source of the high concentrations of CO2 in the soils of the Kerr property is clearly the anthropogenic CO2 injected into the Weyburn reservoir... The survey also demonstrates that the overlying thick cap rock of anhydrite over the Weyburn reservoir is not an impermeable barrier to the upward movement of light hydrocarbons and CO2 as is generally thought." said the report.
The PTRC posted an extensive rebuttal of the Petro-Find report, stating that the isotopic signatures of the , claimed by Mr. Lafleur to be indicative of the manmade  being injected into the reservoir, were in fact, according to studies of  conducted by the British Geological Survey and two other European Union geological groups prior to  being injected at Weyburn, occurring naturally in several locations near the Kerr farm. Subsequent soil surveys after injection in 2002 to 2005 found  levels dropped in these same regions.  In addition, prior to injection occurring into the oil field, these samplings were found to be as high as 125,000 parts per million and averaging 25,000 ppm  across the region, even more than the average and largest readings from the Kerrs property that were being claimed as unusually high. The report also questions, based on seismic imaging conducted over ten years, that any active faults exist or that the caprock is compromised to allow pathways for the  to reach the surface. The PTRC acknowledged that they do not monitor the entire site for leaks, rather primarily above the part of the Weyburn field where  is injected and key locations outside it, but the organization did monitor the Kerrs well between 2002 and 2006, finding no appreciable difference in water quality.  They have also acknowledged that PTRC is a research organisation rather than a regulator, and manage the IEA GHG Weyburn-Midale  Monitoring and Storage Project on behalf of the International Energy Agency's Greenhouse Gas R&D Programme, which includes some 30 international research groups.