The quakes prompted state officials in January to order four fluid injection wells in the eastern part of the state to be "indefinitely" prohibited from opening.

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Further, although thousands of CBM wells are fractured annually, EPA did not find confirmed evidence that drinking water wells have been contaminated by hydraulic fracturing fluid injection into CBM wells.

FORBES: EPA's Fracking Hysteria

In its review of incidents of drinking water well contamination believed to be associated with hydraulic fracturing, EPA found no confirmed cases that are linked to fracturing fluid injection into CBM wells or subsequent underground movement of fracturing fluids.

FORBES: EPA's Fracking Hysteria

Hydraulic fracturing involves the injection of fluid consisting of approximately 99.5% water and sand (the rest consists of common industrial or even household chemicals or materials) through wells constructed with protective casing and cement, into producing shale formations.

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