Three Wyoming County, PA, families near a malfunctioning natural gas well ended up evacuated Wednesday night and Thursday as thousands of gallons of fluid waste escaped from the well before crews could shut it down.
The Marcellus Shale well on Carrizo Oil and Gas’ Yarasavage pad off began malfunctioning during a fracking operation at 6 p.m. Wednesday, said Department of Environmental Protection spokeswoman Colleen Connolly.
The problem worsened overnight when natural gas was leaking from the well and the salty, chemically treated wastewater flowed out at a rate that peaked at 800 gallons per minute before subsiding, according to the company and regulators.
Gas company and specialty well control crews regained control of the well by early Thursday and had it capped by the afternoon.
About 5,400 barrels, or 227,000 gallons, of the fluid ended up captured in tanks and trucked off site, Connolly said. Some of the fluid ran off the pad but crews built a temporary catch basin across the road to contain it, she said.
Four families within 1,500 feet of the well site needed to evacuate Wednesday night because officials said there was concern as the fluid in the well released to the surface, gas would blow out behind it.
“Fortunately, we had the outcome we were looking for,” Connolly said. “There was no major gas buildup, no explosion, no large flare off. Now we need to find out why this happened and what can be done to prevent it from happening again.”
No was injured in the incident. The three families that evacuated to hotels were able to return by Thursday afternoon. A fourth landowner did not evacuate. Carrizo is offering bottled water to families within 1,500 feet of the well and will return to the homes to test their drinking water supplies, although there is no specific indication of contamination, Connolly said.
The problem started while crews were in the 23rd stage of fracking, or hydraulically fracturing, the Yarasavage 1H well, a process of injecting chemically treated water and sand underground at high pressure to crack the gas-bearing shale. The malfunction might have been a flange at the wellhead but the exact cause is unclear.
County EMA director Eugene Dziak said the public was not in any danger.
“We’ve been monitoring the air all night long,” he said. “There has been no release of gas to the atmosphere.”
DEP crews found no detections of volatile chemicals or methane in the air during a sweep of a mile-and-a-half-wide circle around the well. Officials also detected no or very low levels of radiation in the fluid that flowed out of the well, Connolly said.
“There have to be systems in place to collect the flow back water at a certain pace,” Connolly said. “Since this started to flow back so fast, they couldn’t get control of it until this morning.”