Wyoming's Powder River Basin - treated CSG water ...

Excerpt from Casper Star Tribune:

Industry treats more water

6 May 2008

CHEYENNE - More groundwater extracted by coal-bed methane operators in the Powder River Basin is being cleaned so it can be discharged into river drainages, and the trend should continue as operators move into areas of the basin where water quality worsens.

Last year, gas companies treated about 56 million barrels of coal-bed methane water in Wyoming, according to the Wyoming Oil and Gas Conservation Commission. That represents about 8.8 percent of the 638 million barrels of water pumped to the surface by operators in order to extract the gas trapped by water in underground coal seams.

In 2006, 45 million barrels of water, or 6.6 percent, was treated out of 680 million barrels extracted in the state. A barrel of water holds about 42 gallons.

Don Likwartz, supervisor of the Oil and Gas Conservation Commission, said most of the 4.784 billion barrels of coal-bed methane water produced in Wyoming since the late 1980s was clean enough that it didn't need to be treated before being released into drainages and stock ponds.

However, Likwartz said drilling activity is now moving into more areas of the basin where the water quality is not as good because it contains more sodium, barium and other chemicals that make it unsuitable for discharging directly into drainages.

"I do see the treated portion going up both in volume and percentage-wise," he said.

The Powder River Basin extends into southeast Montana, where gas companies removed about 39.4 million barrels of water in 2007, according to the Montana Board of Oil and Gas. The Montana Department of Environmental Quality reports that about 13.7 million barrels of coal-bed methane water, or 35 percent of the total produced, was treated in that state last year.

Treatment is one of several methods of disposing of the water that isn't clean enough to simply dump into nearby waterways. Other methods include using it to irrigate fields in conjunction with soil amendments that counter the high sodium, storing it in large pits or reinjecting the water into the ground.

When conditions don't allow for other methods of disposal, companies must have the water cleaned through processes such as ion exchange and reverse osmosis.

"There's a lot of different technologies, and in all honesty, they are existing technologies that are being reoriented to this specific area," said Dennis Lamb, who oversees coal-bed methane water treatment for the Wyoming Department of Environmental Quality.

The technology also is used in some industrial processes and to produce drinking water in some places, Lamb said.

DEQ recently permitted a new plant near Gillette that can treat up to 30,000 barrels of coal-bed methane water a day.

The drawback to treating the water is the cost.

"Very little has been treated because of the cost," Likwartz said. "They keep saying they hope they can do it for 20 cents a barrel. I don't know of any that have achieved that. Most of them have been more than 30 to 50 cents (a barrel) and higher."

Likwartz said 50 cents a barrel may not sound like much, but it makes a huge difference because of the quantity of water being extracted for the amount of gas recovered. In addition, Wyoming coal-bed methane usually sells for less than methane produced elsewhere, he said.

See - Industry treats more water.