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Slide 23

Again the driller pumps cement down the casing and up the annular space to the surface and waits 8 hours for it to dry.

The primary purpose of this casing is to protect the coal seam from pollution from fluids or from the gas.

Note that it is common for the freshwater and for the coal seam to be drilled, cased and cemented all at once,in one stop. We do not know if that makes for extra dangers.

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