Silverton School officials say they are cautiously optimistic about results so far from exploratory drilling to test the feasibility of a geo-exchange heating system for the school.
A huge drill rig from Geo-Energy Services pulled into town last week and was parked on the school playground. On Friday, drilling began.
The drillers worked through one hole to 210 feet, said Sue Morris, owner’s representative for the school district’s massive renovation project.
That project of course includes a whole new heating system since the school’s old coal-fired boiler bit the dust last fall.
Morris said the goal of the first hole was to drill to 360 feet, but ground conditions prohibited further drilling.
Nonetheless, the drilling hit a constant water source pumping at 5 gallons per minute and approximately 47.5 degrees, Morris said.
“These conditions are good for geo-exchange,” she said.
The second hole at the southwest corner of the playground was halted at 70 feet until the drillers could obtain another drill bit. Drilling resumed Thursday, Sept. 17..
The president of Geo-Energy Services, Trey Austin, will conduct a thermal conductivity test after the second hole is completed.
Josh Druege, mechanical engineer for Geo-Energy Services, was on the playground last week as drilling began.
“What we’re anticipating here is finding ground with a temperature of about 45 degrees,” Druege said. “We can still extract heat from that.”
He said the process involves using “just a little bit of energy” to boost refrigerants to a level that is extractible to be converted to heat.
A system for the school and gym, he suggested, if it is found feasible, might involve 60 loops of small tubes each moving three or four gallons of refrigerant per minute deep below the playground.
“The thing I appreciate so much about this system is that while it seems very, very complicated, but it’s actually very simple,” Druege said.