Crew members work to contain a spill of hydraulic fracturing fluids at a well blowout on April 19 in Bradford County, PA. Photo courtesy of Protecting Our Waters.

Methane concentrations grew so strong following an April 19 blow-out at a natural gas well operated by Chesapeake Energy in northeastern Pennsylvania that the company cleared the area of crew members and equipment in case the facility exploded, according to documents detailing the incident obtained by NaturalGasWatch.org.

Following the April 19 blow-out, which sent tens of thousands of gallons of toxic fracking fluids coursing over Bradford County, Pennsylvania farmland and into a nearby creek, the federal Environmental Protection Agency (EPA) directed Chesapeake to disclose information related to the incident.

Much of that information has not been released by the EPA. The few documents that have been made public, though, detail an incident that quickly overwhelmed Chesapeake’s on-site personnel and could have resulted in a potentially lethal explosion.

From the Chesapeake response:

At approximately 7:00 PM on April 20, after consultation with the well control team, and to mitigate further risk to personnel and equipment, plans were finalized to mobilize the completions crew and all non-essential equipment off location. Equipment was removed, the primary containment was repaired, the location was cleared, and all ignition sources were removed from location. This work continued until 11:15 PM, when the Lower Explosive Limit (“LEL”) monitors registered low methane levels at the wellhead. At this time the location was cleared of personnel and equipment and secured until daylight.

After reviewing the documents, NaturalGasWatch.org has pieced together a timeline of the incident.

April 18, 2011 – Hydraulic fracturing operations begin at Chesapeake Energy Corp.’s Atgas 2H well.

April 19, 2011, 11:15 p.m. – Wellhead at Atgas 2H begins to leak.

April 20, 2011

• 12:30 a.m. – First well control team member arrives on scene.
• 1:03 a.m. – Chesapeake local manager arrives on site.
• 1:15 a.m. – Third well supervisor arrives on site.
• 6:47 a.m. – First plugging attempt. Reduces flow “only a small amount.”
• 8:00 a.m. – Fourth well control team member arrives on site.
• 10:00 a.m. – Second plugging attempt, reduces flow by 50 percent.
• 12:27 p.m. – Third plugging attempt.
• 1:00 p.m. – Fourth plugging attempt. Flow reduced by 70 percent.
• 7:00 p.m. – Chesapeake moves crew and “non-essential” equipment off site to “mitigate further risk.”
• 11:15 p.m. – Monitors register low methane levels, containment attempts cease until daybreak.

April 21, 2011

• 5:45 a.m. – Flow from well turns primarily to gas.
• 3:50 p.m. – Fifth well attempt to plug well. Flow successfully stemmed.

April 25, 2011, morning – Permanent control achieved.

The document released by the EPA also confirm that the primary mechanism Chesapeake had in place to deal with spill failed. Chespeake blamed heavy rains for the failure.

From Chespeake’s response:

Once on site at approximately 2:30 AM (2 hours 45 minutes after the initial call), Chesapeake’s support personnel, in coordination with the well control team, considered options to address the discharge at the point of discharge. Concerns for worker safety, however, precluded the movement of construction equipment to the pad to bolster the primary containment. In addition, saturated ground conditions precluded access to the base of the containment throughout the night.

The entire document can be found here:  Chesapeake_response_to_EPA