These operators also place an emphasis on appropriate casing designs and cementing practices to maintain wellbore integrity and protect the freshwater aquifers.

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Thus the industry has for decades relied on a dense mud system to keep the hydrocarbons in the reservoir and everything that is done to maintain wellbore integrity is tested, and where a wellbore integrity test fails, remedial action is taken.

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You could either do it separately if the integrity of the wellbore has been maintained through the explosion, and if not, it helps when the relief well intersects to the well in having a separate point of pressurization for mud and cement.

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