"Chesapeake Energy Nomac Rig 17 Blowout Could Have Been Prevented" Oklahoma State Regulator Says

Blowout Could Have Been Prevented
State regulator says Chesapeake did not comply with rules

A natural gas blowout in Roger Mills County earlier this year could have been prevented, according to an incident report filed by state regulators.

An engineer with the Oklahoma Corporation Commission wrote that Chesapeake Energy never reported the failure of a well casing in a nearby well.

Chesapeake's own internal investigation concluded that the #17 Nomac rig four miles northwest of Sweetwater, OK unexpectedly drilled into a reservoir of natural gas that had escaped from a well about half a mile to the north.

The report states that the well casing, which keeps gas and materials inside the hole, had failed about six months before the January 5 blowout. Chesapeake knew about a problem then when they found drilling mud and shale in their equipment and lines, and their gauges experienced pressure changes.

That hole was shut in, according to the report, but "gas and possibly fluids" charged a previously dry zone of limestone about 925 feet below Earth's surface.

When drillers on #17 Nomac reached that depth, the pressure from the gas blew out the well and ignited gas, causing major structural damage to the rig. It took six days for the well to come back under control. It was only then that Chesapeake notified the OCC about problems with the other well to the north, according to the incident report.

Chesapeake is also accused of violating another OCC rule that requires a blowout preventer to be installed before drilling out of the surface casing.

The incident report notes that the creation of the shallow gas reservoir could have been prevented or mitigated if Chesapeake notified OCC and fixed the problem in the summer of 2011. It also states that the blowout could have been controlled if a blowout preventer had been installed earlier in the drilling process.

Chesapeake paid $75,000 to the OCC because of problems that led to the blowout, but is not admitting any wrongdoing.
The company reportedly has instituted "a new internal policy of checking data from wells offsetting any proposed new well in this area for indications of potential similar problems."

The Corporation Commission is expected to issue a final ruling on the matter Thursday.

Source: Daily Elk Citian