Planned drilling targets Baton Rouge – area shale deposits
Public hearing set on use of ‘fracking’ to extract oil
By AMY WOLD Advocate staff writer Published: May 2, 2011
An oil-rich shale beneath parts of the Baton Rouge area could soon be tapped on a large scale through hydraulic fracturing, a technique that has raised environmental concerns elsewhere.
High oil prices have made hydraulic fracturing, or “fracking,” an economically feasible way to extract oil and gas that in the past were too difficult to get at.
Environmentalists and some people living near such drilling contend fracking pollutes the air, contaminates water and overtaxes water resources — claims the industry argues are unfounded.
The state will hold a public hearing as early as June on whether to approve a drilling production unit in the Tuscaloosa Marine Shale near Ethel in East Feliciana Parish. Devon Energy, based in Oklahoma City, wants to use fracking, said James Welsh, commissioner of the Louisiana Office of Conservation.
“This will be Louisiana’s Eagle Ford,” Welsh said referring to a shale area in Texas that has seen a recent boom in production.
Devon Energy spokesman Tony Thornton said it’s too early for the company to talk about the permit application.
Fracking was employed on one of the four wells already drilled in the Tuscaloosa Marine Shale. But Devon Energy’s proposal marks the start of what is expected to be intensive fracking in the shale.
Madhurendu Kumar, director of the state Office of Conservation’s geological oil and gas division, said Devon Energy’s application for a production unit shows the company believes the area around the well contains multiple leases. It’s a first step toward greater development of the shale, he added.
Since 2008, “fracking” has occurred mainly in north Louisiana’s Haynesville Shale for extracting natural gas. In the Tuscaloosa Marine Shale, the target is oil.
The Tuscaloosa Marine Shale stretches about 200 miles east to west and is about 45 miles wide. A 1997 LSU study estimates there is 7 billion barrels of oil in the shale, Kumar said.
Hydraulic fracturing involves drilling down to the shale layer, then horizontally across the shale. The horizontal pipe is punctured so a high-pressure water/chemical mix can crack the shale, allowing oil or gas to be collected.
The liquid forced into the shale contains a propping agent that helps hold the fractures open, Welsh said. It also can include chemicals that kill bacteria in the water or prevent corrosion and deposits in the pipe. The formulas vary depending on what is needed at each well.
The chemicals that producers use are considered proprietary. The U.S. Environmental Protection Agency has started requesting that information as part of an upcoming study. Some companies have released the makeup of their fracking liquid, while others have resisted.
Barry Kohl, an adjunct professor of geology at Tulane University, said reports from across the country suggest that problems exist with hydraulic fracturing, including water contamination.
“The chemicals they use are secret formulas that they won’t release even to EPA,” said Kohl, who said he worked in the oil industry for 26 years.
Another concern is that the large volume of water needed for the fracking process will deplete underground aquifers or draw down lakes and streams, Kohl said.
Welsh said the state conservation office encourages companies to use surface water when possible, and 72 percent of the water used in the Haynesville Shale comes from such sources.
Some wells rely on the Red River alluvial aquifer, which is very mineralized and doesn’t make good drinking water, he added.
“But it makes wonderful ‘frack’ water,” Welsh said.
Other concerns include air pollution from production, management of the water that comes back out of the well, and noise and vibrations caused by the fracking process.
Welsh counters that hydraulic fracturing has been used in the state for decades without a problem. He said it’s impossible fracking would harm ground water in Louisiana because almost two miles of earth separates drinking water aquifers from fracking activities.
Underground water supplies lie about 2,500 feet below the surface, while the Tuscaloosa Marine Shale is 12,000 to 13,000 feet deep, he said.
When a well is drilled, several casings are installed to prevent any fracking liquid, oil or gas from migrating from the well itself, he said.
“So you have a seal of surface casings,” Welsh said. “It’s our job to see that the drilling that is done is safe. That’s our job. That’s what we do.”
Kohl said another concern is the fracturing process itself.
Fracking wells are similar to injection wells used by industry to dispose of hazardous materials deep underground, Kohl said. Those injection wells have leaked in the past, which means the same could happen with hydraulic fracturing wells.
Without careful planning, Kohl said, it’s possible some high-pressure wells could hit Louisiana’s geologic faults.
If that happens, he said, material pumped into the wells could migrate up through the faults and other cracks to the drinking-water level. Natural gas could seep to the surface, possibly contaminating small streams, he said.
“Those are the sorts of things, from a geologic perspective, that I can see that one has to be very cautious about,” Kohl said.
Kohl contends the push to extract natural gas and oil in marine shale deposits has accelerated so quickly — fueled in part by higher prices — that it’s been hard for states to stay ahead of the game by adopting more-stringent safety regulations.
The state’s argument that no water-contamination problems have stemmed from fracking in the past holds little comfort, he said.
A recent review of Louisiana’s hydraulic fracturing procedures contained both praise and recommendations for improvement.
The State Review of Oil and Natural Gas Environmental Regulations — a nonprofit group that helps states examine oil-and-gas environmental regulations — reported the strengths of Louisiana’s oversight include water-use monitoring requirements rule changes that let producers to reuse fracking liquid to reduce water use.
The group suggested that the Office of Conservation review casing and cementing standards with an eye toward protecting drinking water.
Another recommendation is having producers report to the state the amounts of all chemicals used in fracking.
The U.S. Environmental Protection Agency is conducting a study into the impacts of hydraulic fracturing. Preliminary results could be made public by the end of 2012.
ON THE INTERNET:
Louisiana Hydraulic Fracturing State Review, March 2011
Posted on May 2, 2011, in City - LA, Natural Gas, Oil & Gas - inland, Shale Gas, Shale Oil, United States and tagged City - LA, Devon Energy, Drilling, energy, Haynesville Shale, Hydraulic fracturing, Natural Gas, Oil & Gas - inland, Shale gas, Tony Thornton, Tulane University, United States, United States, United States Environmental Protection Agency. Bookmark the permalink. 1 Comment.