The city of Aspen is giving up on the geothermal test well it’s been drilling since the fall of 2011 and digging another hole 20 feet away.
The city’s contracted driller, Dan’s Water Well and Pump Service, resumed the drilling project in mid-April, working on the hole it had capped and plugged with concrete nearly two years ago. They had reached more than 1,000 feet below the surface, but had not hit water.
According to city utility efficiency manager Jeff Rice, the new round of drilling was plagued by instability after reaching about 500 feet, where alluvial soil was crumbling and filling in the hole.
“The alluvial [layer] is caving in,” Rice said. “So we’re moving over 20 feet and starting fresh.”
Rice said the move will not impact the city’s $273,260 budget for the project.
Last year in the spring, and again in the fall, the city planned to resume work on the project in the Prockter Open Space across Neale Avenue from Herron Park, but could not come to an agreement with the drillers. The work has been limited to the off-seasons — and to an eight- to 10-hour schedule six days per week — as part of a deal between the city and neighbors.
City officials and drillers made the decision this week to start over, and Dan’s California-based team has taken a break from the project, leaving the equipment in place this weekend. They are scheduled to resume drilling on Monday. Though the project is starting over, its end date remains the same. The deadline for completing this phase of drilling is Monday, May 27.
Chris Council/Aspen Daily News
The geothermal test site at the Prockter Open Space parking lot was quiet on Friday morning due to the project being temporarily halted. Work is expected to resume on Monday when drillers start a new hole 20 feet away.
The drilling project is part of a city initiative launched in 2008 that aims to tap geothermal energy to heat or cool buildings. Historical mining accounts indicate there is geothermal potential below the city. The Prockter hole would be the first of multiple test wells before energy could be generated, if the water is hot enough.
The second attempt will use a different process that involves installing casing in the hole as they drill — theoretically protecting it against caving in on itself as the initial well did.
“I said, ‘Please, tell me, if you’re moving over, that you’re not drilling the same way,’” Rice explained.
The city has spent $179,000 on the project so far, which includes a $50,000 state grant.
The project has spawned controversy on two fronts over the last two years. Neighbors initially complained they hadn’t been notified that the project, along with its industrial noise and heavy equipment, was coming. All households within 350 feet of the drill site were notified before this spring’s work began. Also, some city critics have balked at the six-figure budget for a project with uncertain results.
But the project has received continued support from Aspen City Council, which has a stated goal of making the city’s energy profile 100 percent renewable by 2015.
City officials are hoping for some of the geothermal success enjoyed by Pagosa Springs, where geothermal energy heats 34 buildings, including private businesses, government buildings and some homes. There, it took two years from its first test well — in 1980 — to successfully heating buildings in 1982.
Rice said he and the team from Dan’s believe starting over is a successful strategy for hitting hot water.
“We are confident and they are confident,” said Rice.