Gas drillers pumped 8.3 million gallons of liquid under high pressure to fracture a gas-bearing Marcellus Shale formation near Canton, Ohio. About two dozen chemicals included in the fracking fluid were disclosed on a public website — but the identities of another four chemical ingredients were withheld on the claim that they were trade secrets.

EnergyWire's Peter Behr takes a long look at the controversy over disclosure of fracking fluid ingredients under Ohio's new rules. Similar partial-disclosure rules are at issue in other states as well.

• "NATURAL GAS: Fight Escalates Over Chemical Secrecy In Hydraulic Fracturing," [2] EnergyWire, June 25, 2012, by Peter Behr.