Coalbed methane: Alaska's newest energy source.

• Author: Ehm, Arlen

With the present decline in oil and gas production, a new energy potential is emerging that could provide a new impetus in resource development for the state. Coalbed methane, or more properly, coalbed gas, is present in Alaska in enormous quantities.

For many years, attempts have been made in rural Alaska to create local energy sources that would preclude or diminish the dependence on diesel fuel in rural areas.

Geothermal energy was tried at one time, but the remoteness of the villages, the great expenses involved, and the usually poor location of the village with respect to the resource, have generally thwarted such efforts.

Coalbed methane may provide a solution. This gas can be developed from the state's vast coal deposits, and done so in an environmentally sound manner - without any surface or subsurface disturbance.

Wasilla's Testing Ground

Producing coalbed methane is not a new idea. In fact, coalbed methane operations are active in several areas of the Lower 48, notably the San Juan Basin of New Mexico - the world's most prolific coalbed methane basin with cumulative production exceeding one trillion cubic feet of gas.

Other areas with lesser potential include the Black Warrior Basin of Alabama and the Piceance, Greater Green River and Powder River Basins in the Rocky Mountain areas.

It was the Alaska Department of Natural Resources who led the state's efforts to create a coalbed methane program. In 1994, the Division of Oil and Gas, a division of the DNR, drilled Alaska's first coalbed methane well near Wasilla.

This well, AK-94CBM-1, was drilled and cored to a total depth of 1,245 feet using a rig owned by the U.S. Geological Survey. The well was continuously cored below a depth of 354 feet where a cumulative thickness of 41 feet of coal was present in beds up to 6.5 feet thick.

The cores were placed in canisters and later tested for gas content, the results proving the viability of coalbed methane exploration in the upper Cook Inlet Basin.

The first commercial activity was initiated by David Lappi who acquired a farm-out from Unocal near Houston. He later joined forces with Growth Resources Inc. of Australia and they drilled three wells last winter.

One of these wells is presently being "de-watered" by pumping the water from the coal seams and injecting the water into a lower permeable zone. This process may take several months or a few years, and it is necessary to remove the water in order for the gas to ultimately flow.

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