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State geologist advocates use of coalbed methane for rural villages Sixth year of research program, three remote sites in Alaska identified as high potential locations for alternative energy source Patricia Jones Contributing Writer Editor’s note: This fourth in a series of five articles about a remote energy conference held in Fairbanks in September. Government geologists have identified three rural Alaska villages with high potential for tapping coalbed methane gases as an alternative energy source and hope to land research funding to prove up this resource.
Wainwright, Fort Yukon and Chignik Lake are all communities high on the priority list for the state and federally funded coalbed methane research, designed to identify and hopefully drill a producing well that could replace diesel as a rural energy source.
“This is not to say any that other areas don’t have potential, but if you’re going go out and do drilling program and have some success, you want to go with an area with the most evidence,” said Jim Clough, energy section chief at the state Division of Geological and Geophysical Surveys.
During a remote energy conference held in Fairbanks in September, Clough gave a presentation on coalbed methane work completed by DGGS, the U.S. Geological Survey and the U.S. Bureau of Land Management.
He said the $1 million spent on coalbed methane research , which includes various field projects dating back to 1996, has produced promising finds that need to be proved up with drill work, contemplated for later this year and in 2003.
“The truth of the matter is that we really don’t know … villages can be right on or right next to it, but we don’t know if gas is at depth until we drill it,” he said.
Coalbed methane, which historically has been considered a mining hazard, has only been considered a potential energy resource in the last two decades, Clough said. It requires fractures within a coal seam and the presence of water to produce the usable gas.
Low rank coal tends to produce more gas, and Alaska is well endowed with that natural resource. Based on the 5.5 trillion short tons of coal known to be in Alaska, Clough’s group estimates that there could be 1,037 trillion cubic feet of coalbed methane gas locked up in the state’s underground formations. Chignik scheduled for November Clough and other coalbed methane researchers plan to observe a water well drilling project at Chignik Lake starting in early November. The community, located southwest on the Alaska Peninsula, obtained funding through the Alaska Native Tribal Health Consortium to create new water wells for the residents in the area.
Clough said the coalbed methane researchers will be on stand-by, to “see what comes up in these drill holes … see what the coals look like.”
The minerals research consortium also provided funds for some of the drilling effort, he said, in order to look at the results. That amount totaled $75,000, which includes expenses to participate in the early November drilling work, Clough said.
The Chignik area stood out in the early efforts of the coalbed methane research, he said, due to a number of factors.
Anecdotal talk included information about gases present in small coal mines in the area, he said. In addition, old geological information about a coal prospecting effort reported the presence of methane in the area.
Furthermore, some exploratory oil and gas wells drilled in the Bristol Bay area in the late 1970s and early 1980s reported gas kicks on the drill logs, Clough said.
Finally, the two communities, combined with fish processing facilities in the summer, would provide enough of an energy resource need to draw on coalbed methane, should it be produced, Clough said.
Fort Yukon work next year The next step is to actually drill for coalbed methane, Clough said. Fort Yukon is the site selected for that effort, based on several factors.
For starters, a drilling crew providing information for a pollen study hit gases when drilling at the Fort Yukon Air Force site in 1994, Clough said. That drilling work, which had gone 1,280 feet below the surface, stopped when hitting the unidentified gases.
“Apparently it was very gassy and they quit, concerned about a spark igniting the gas,” he said. “There’s no guarantee the gas was methane — it could be CO2 — but having it in coal, it’s very likely it’s methane.”
That group also identified a coal seam that was 28 feet thick, Clough said. That’s where the gas was coming out, “hissing and popping,” he said.
Unfortunately, the drilling crew didn’t encapsulate the gases in a canister with a valve, traditional method for determining the content and quantity of the material, Clough said.
“It could have also been just 28 feet of coal, a very small area, not enough to substantiate a program to go out and drill and test the coal,” he added.
Based on that past experience, Clough’s group opted to conduct a shallow seismic survey of the Fort Yukon area to better quantify the underground resources.
That work, completed in the spring of 2001, provided eight and one-half miles of seismic information, including an area surrounding the 1994 drill site, Clough said.
Seismic work revealed that the underground coal seam is much thicker, about 60 feet, he said. “The reflectors beneath it indicate another zone of coal — about 80 to 90 feet down — another zone up to 60 feet thick,” Clough said. “It’s very promising, extremely favorable … that’s where we want to go next.”
Depending on funding available for such a drill project, Clough said the group is considering re-opening the 1994 drill hole. “We could take a small drill rig out there … reenter the hole with a slim hole drill and get a coal from the coal seam,” he said.
The group would also measure gas content from the coal and collect water data from the well, necessary in providing an accurate analysis of production possibilities for the coalbed methane.
That small drill project would take anywhere from $200,000 to $400,000, he said.
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