Recent studies have shown an increase in the percentage of wells affected by sustained casing pressure, over time. Both the oil and gas industry, and governments, are studying the causes of sustained casing pressure, and methods to help prevent undesired flow that can, potentially, result in the loss of wellbore integrity and environmental problems. In northern Colombia, natural gas fields have been developed for decades. However, as a result of mechanical problems, or low economic return rates, some producing wells have been abandoned. Some of the wells were abandoned using conventional cementing techniques without success, resulting in gas communication, through the annulus, to the surface. In some cases, this even has been observed where the primary top of cement (TOC) was planned to surface.

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