Anatomy of a Gas Well
Several layers of steel casing typically enclose a well bore. The empty spaces between can be sealed with cement.
The promise of abundant natural gas is colliding with fears about water contamination.
The Story So Far
The country’s push to find clean domestic energy has zeroed in on natural gas, but cases of water contamination have raised serious questions about the primary drilling method being used. Vast deposits of natural gas, large enough to supply the country for decades, have brought a drilling boom stretching across 31 states. The drilling technique being used, called hydraulic fracturing, shoots water, sand and toxic chemicals into the ground to break up rock and release the gas.