If approved the quarry would release five million tonnes of new sand and gravel reserves.

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About 25, 000 wells a year are being fracked, a process in which water, chemicals and sand are injected at high pressure underground to release trapped natural gas.

NPR: Report: Flaws In EPA Drilling Pollution Data

Fracking involves drilling horizontally into the rock, forcing sand and water underground to cause tiny fractures that release gas from the shale.

BBC: NI shale gas deposits 'could be worth ?80bn' says report

Fracking uses high-pressure mixtures of water, sand or gravel and chemicals to crack rock formations and release oil and natural gas deep underground.

NPR: Scenic, Struggling S. Illinois Braces For Oil Rush

This year he completed what is believed to be the first ever fracture stimulation procedure in Turkey: injecting a mixture of water and sand at high pressure down the wells to break up rock and release gas.

FORBES: Magazine Article