UH researchers eye doubling number of geothermal survey sites

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After obtaining permits in March to begin exploring for geothermal energy under the dormant Hualalai volcano, researchers with the University of Hawaii are looking to more than double the number of survey sites included in the project.

After obtaining permits in March to begin exploring for geothermal energy under the dormant Hualalai volcano, researchers with the University of Hawaii are looking to more than double the number of survey sites included in the project.

Donald Thomas, director of The Center for the Study of Active Volcanoes at UH-Hilo, said part of the rationale behind the request is to avoid costly environmental assessments.

Thomas said the state Department of Land and Natural Resources informed project researchers that some of the original nine parcels required the study. He said a decision was made to abandon certain sites and add others that would not require environmental assessments.

“We were provided a fixed amount of money to do the surveys,” Thomas said. “And we were not at all in a position to do an environmental assessment.”

The request would increase the number of locations permitted for non-invasive geophysical study along the Hualalai Rift Zone, just north of Kailua-Kona, from nine to 19.

The state Land Board is scheduled to consider the matter during its meeting Friday.

The project, the first exploration permit in an overall effort referred to as the “Geothermal Resources Exploration Plan for Hawaii,” is funded by the DLNR and U.S. Department of Energy.

Researchers plan to conduct their surveys on up to 19 parcels of land, all zoned agriculture. The landowners include the state, Kamehameha Schools, Makalei Golf Club, the Queen Lili‘uokalani Trust, Palani Ranch, the state Department of Hawaiian Homelands, Lanihau and others.

Researchers will use a standard technique called a magnetotelluric survey, which maps the electrical conductivity of rocks at depths from several hundred feet to as much as 20,000 feet below the surface.

“The vast majority of developed geothermal systems in the world are located in regions where water can flow naturally through the heated rock formations,” researcher Nicole Lautze, with the Hawaii Institute of Geophysics and Planetology, said in her original application. “Being able to identify the subsurface heat source and fractured zones allows us to begin to address some of the problems of geothermal exploration and development.”

The system uses antennas and electrodes to measure naturally occurring, very low-frequency electromagnetic waves. The apparatus does not generate electrical signals nor transmit energy.

Thomas said environmental assessments cost $100,000 or more — far more than the money set aside for the project. The project’s impact, however, he said, will be minimal.

While researchers plan to survey 1 million square meters of land, less than 3 square meters will be impacted by equipment, according to Thomson.

“I figured out my garden at home impacts more land than our entire survey would impact,” he said.

Thomas said work could commence as early as this summer, and he hopes the study will generate useful information, about geothermal energy and groundwater.

The Big Island’s geothermal production currently is limited to one 38-megawatt power plant, Puna Geothermal Venture, outside Pahoa.

Friday’s board meeting begins at 9 a.m. in Honolulu.

Email Chris D’Angelo at cdangelo@hawaiitribune-herald.com.