Tech Drilling Mountain In Search Of Hot Water

SOCORRO – Drilling is underway in a search for an inexpensive renewable energy source to heat the buildings of New Mexico Tech.

After months of boring several previous exploratory sites along the base of ‘M’ Mountain, technicians began drilling in earnest November 17 in a search for hot water to provide geothermal energy.

Geoscientists at Tech believe there is a reliable source of geo-thermal energy that can provide the university with an efficient, inexpensive heating and cooling system, as well as reduced energy bills.

In 2004, U.S. Department of Energy’s Geothermal Resource Exploration and Division awarded Tech geochemistry professor David Norman and geophysics professor Harold J. Tobin a $503,172 grant. The purpose was to conduct research and exploratory drilling to accurately evaluate the geothermal potential in the previously designated “Known Geothermal Resource Area,” which surrounds ‘M’ Mountain.

Norman is working with James C. Witcher of Witcher and Associates, a geothermal consulting firm in Las Cruces.

“Water heated by geothermal waters through a heat exchanger will circulate around campus through a pre-existing hot-water loop, providing space heating for most of the university’s buildings,” Norman said. “This would require geothermal waters of at least 150 degrees Fahrenheit.”

Although the water Norman and Witcher are drilling for is separate from Socorro Springs, the area is geologically active.

“There are springs and anomalies all along the base of Socorro Peak,” Norman said. “We looked for evidence of fractures in the bedrock.”

A site was chosen above a large fracture on the front of ‘M’ Mountain at an elevation several hundred feet above Socorro. The light generated by powerful halogen lamps can be seen every night in Socorro as the drilling goes on night and day.

“The first 80 feet was all gravel, which makes the going slow. When you drill in gravel, it tends to fill in as you go,” Witcher said. “It’s unstable, so it’s good to get past that. Now we’re hitting rocks and things are going smoother, but we’re still working through broken rock and we still have to be careful. When we get closer to 300 feet we’ll be getting an idea of the heat of the water below. We’ll get good answers at about 1,500 feet.”

As of Wednesday the drill had reached a depth of about 200 feet.

“If we’re lucky and we hit boiling water then we’ll be able to generate electricity by installing turbines,” he said. “That electricity would be used to heat the boilers that are now heated with natural gas. This could reflect an annual savings of $1.2 million for Tech.”

The drilling is a 24-hour-a-day operation with a driller and two helpers always present. In addition there’s a drilling foreman, and geologists from Tech.

Geology post-graduate students Amber McIntosh and Lara Owens each work eight hour shifts at the site.

“We log the cores, looking at the geology of the samples, and evidence of fractures. That’s what carries the water,” McIntosh said.

Witcher said the drilling is done with a diamond bit, “which cuts instead of grinds. Core tools are not the same as rotary tools.”

Once hot water is found, the next step is to circulate it through pre-existing pipes.

According to Norman, around 1980 there was a study looking at the potential for using geothermal water as a heat source, but it was decided that drilling for hot water would be costlier and riskier than installing solar collectors atop buildings to heat water for the campus hot-water loop. That solar-generated water heating system never worked as planned and it eventually fell into disrepair.

The hot-water loop still circulates hot water to buildings throughout the New Mexico Tech campus, but the water is heated by natural gas heaters at a significant expense to the university.

Norman, Tobin, and Witcher are confident that the current drilling will result in a reliable renewable source of energy that can be used to heat, as well as cool, all buildings on the New Mexico Tech campus.