Cold can pose drilling pad plumbing problems
Cold weather brings litany of challenges to the gas fields
Every homeowner knows how the winter cold can test a property’s plumbing.
It turns out, energy companies face the same ordeal.
Frozen valves and other maladies, including operator errors trying to deal with cold-weather challenges, have resulted in at least a half-dozen leaks and spills at Garfield County natural gas sites in the past few months, and a few more in Rio Blanco County, according to Colorado Oil and Gas Conservation Commission records.
Such problems aren’t unusual this time of year, said Chris Canfield, an environmental protection specialist for the agency.
“Winter weather presents a challenge for the operators, and some of the equipment is susceptible to freezing,” Canfield said.
Most of the leaks and spills are small in volume, “measured in gallons rather than barrels,” he said. They’re generally contained within berms on a well pad, and companies try to learn from the incidents to try to prevent similar problems from occurring, he said.
Susan Alvillar, a spokeswoman for Williams Production RMT, agreed that freeze-related spills are one of the extra challenges created by wintertime natural gas operations. This is also the time of year when contractors often must use tire chains on their trucks, and drilling rigs sometimes are wrapped in tarps to help keep workers warm and prevent ice buildup on stairs, among other accommodations to winter, she said.
She said Williams takes numerous steps to try to prevent spills, such as using frost-free valves, locating valves inside buildings where possible, heating fluid lines, and installing berms so spills can be contained if they occur.
Fortunately, she said, when spills happen, they usually involve water rather than petroleum-type fluids, which are less prone to freezing.
Over the years, companies have increasingly shifted toward using tank-based, closed-loop drilling systems rather than open pits. But Alvillar said Williams tends to use more pits than tanks in its drilling operations in the highlands north of Parachute. Above-ground tanks in the wintertime require heating, and sometimes the heaters can have issues, she said. The challenges presented by tanks can be magnified at higher elevations, where temperatures are colder and well pads are more remote.
Drilling pits can pose their own problems. In mid-2008, the state imposed monitoring and other requirements for pits above the Parachute and Roan creek drainages following spills from pits above the town of Parachute the previous winter.
Alvillar said Williams uses monitoring systems for all of its higher-elevation pits, so any leaks can be detected from remote locations. She said the Bureau of Land Management’s White River Field Office in Meeker has nominated Williams for a best-management-practices award from the agency for the leak-detection systems and other pit-management methods it uses on area federal lands.
Canfield said no matter which way liquids are managed, it’s just a matter of managing them correctly. Despite the freeze concerns related to use of tanks, tank leaks tend to be discovered more quickly than pit leaks, because the leaks occur above ground, he said.
BLM spokesman David Boyd said the agency’s field office in Silt often prefers to see the closed-loop systems used, for reasons such as the fact they minimize a well pad’s footprint. But whether such systems or pits are the best approach can depend on the situation, and Williams’ award nomination reflects the fact that where it uses pits, it’s doing a good job with them, he said.