Deep in Bedrock, Clean Energy and Quake Fears By JAMES GLANZ
New York Times: June 23, 2009
"BASEL, Switzerland — Markus O. Häring, a former oilman, was a hero in this city of medieval cathedrals and intense environmental passion three years ago, all because he had drilled a hole three miles deep near the corner of Neuhaus Street and Shafer Lane.
He was prospecting for a vast source of clean, renewable energy that seemed straight out of a Jules Verne novel: the heat simmering within the earth’s bedrock.
All seemed to be going well — until Dec. 8, 2006, when the project set off an earthquake, shaking and damaging buildings and terrifying many in a city that, as every schoolchild here learns, had been devastated exactly 650 years before by a quake that sent two steeples of the Münster Cathedral tumbling into the Rhine."
Hastily shut down, Mr. Häring’s project was soon forgotten by nearly everyone outside Switzerland.
As early as this week, though, an American start-up company, AltaRock Energy, will begin using nearly the same method to drill deep into ground laced with fault lines in an area two hours’ drive north of San Francisco.Residents of the region, which straddles Lake and Sonoma Counties, have already been protesting
swarms of smaller earthquakes set off by a less geologically invasive
set of energy projects there. AltaRock officials said that they chose the spot in part because the history of mostly small quakes reassured them that the risks were limited.
SNIP
But in a report on seismic impact that AltaRock was required to file,
the company failed to mention that the Basel program was shut down because of the earthquake it caused. AltaRock claimed it was uncertain that the project had caused the quake, even though Swiss government seismologists and officials on the Basel project agreed that it did.
Nor did AltaRock mention the thousands of smaller earthquakes induced by the Basel project that continued for months after it shut down.
The California project is the first of dozens that could be operating in the United States in the next several years, driven by a push to cut emissions of heat-trapping gases and the Obama administration’s support for renewable energy.
SNIP
Power companies have long produced limited amounts of geothermal energy by tapping shallow steam beds, often beneath geysers or vents called fumaroles.
Even those projects can induce earthquakes, although most are small. But for geothermal energy to be used more widely, engineers need to find a way to draw on the heat at deeper levels percolating in the earth’s core.
Some geothermal advocates believe the method used in Basel, and to be tried in California, could be that breakthrough.
But because large earthquakes tend to originate at great depths, breaking rock that far down carries more serious risk, seismologists say. Seismologists have long known that human activities can trigger quakes, but they say the science is not developed enough to say for certain what will or will not set off a major temblor.
SNIP
The tone is more urgent in Europe. “This was my main question to the experts:
Can you exclude that there is a major earthquake triggered by this man-made activity?” said Rudolf Braun, chairman of the project team that the City of Basel created to study the risks of resuming the project.
“I was quite surprised that all of them said: ‘No, we can’t. We can’t exclude it,’ “ said Mr. Braun, whose study is due this year.
“It would be just unfortunate if, in the United States, you rush ahead and don’t take into account what happened here,” he said.
Basel’s Big ShockBy the time people were getting off work amid rain squalls in Basel on Dec. 8, 2006, Mr. Häring’s problems had already begun.
His incision into the ground was setting off small earthquakes that people were starting to feel around the city.Mr. Häring knew that by its very nature, the technique created earthquakes because it requires injecting water at great pressure down drilled holes to fracture the deep bedrock. The opening of each fracture is, literally, a tiny earthquake in which subterranean stresses rip apart a weak vein, crack or fault in the rock. The high-pressure water can be thought of loosely as a lubricant that makes it easier for those forces to slide the earth along the weak points, creating a web or network of fractures.
Mr. Häring planned to use that network as the ultimate teapot, circulating water through the fractures and hoping it emerged as steam.
But what surprised him that afternoon was the intensity of the quakes because advocates of the method believe they can pull off a delicate balancing act, tearing the rock without creating larger earthquakes.Alarmed, Mr. Häring and other company officials decided to release all pressure in the well to try to halt the fracturing.
But as they stood a few miles from the drill site, giving the orders by speakerphone to workers atop the hole, a much bigger jolt shook the room.“I think that was us,” said one stunned official.
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Bracing for TremorsThere was a time when Anderson Springs, about two miles from the project site, had few earthquakes — no more than anywhere else in the hills of Northern California. Over cookies and tea in the cabin his family has owned since 1958, Tom Grant and his sister Cynthia Lora reminisced with their spouses over visiting the town, once famous for its mineral baths, in the 1940s and ’50s. “I never felt an earthquake up here,” Mr. Grant said .
Then came a frenzy of drilling for underground steam just to the west at The Geysers, a roughly 30-square-mile patch of wooded hills threaded with huge, curving tubes and squat power plants. The Geysers is the nation’s largest producer of traditional geothermal energy.
Government seismologists confirm that earthquakes were far less frequent in the past and that the geothermal project produces as many as 1,000 small earthquakes a year as the ground expands and contracts like an enormous sponge with the extraction of steam and the injection of water to replace it.
at just do not want to stay together.
SNIP
Residents have been fighting for years with California power companies over the earthquakes, occasionally winning modest financial compensation. But the obscure nature of earthquakes always gives the companies an out, says Douglas Bartlett, who works in marketing at Bay Area Rapid Transit in San Francisco, and with his wife, Susan, owns a bungalow in town.
“If they were creating tornadoes, they would be shut down immediately,” Mr. Bartlett said.
“But because it’s under the ground, where you can’t see it, and somewhat conjectural, they keep doing it.”Now, the residents are bracing for more...
SNIP
The steam is what originally drew the power companies here.
But the AltaRock project will, for the first time, drill deep into the felsite. Mr. Turner said that AltaRock, which will drill on federal land leased by the Northern California Power Agency, had calculated that the number of earthquakes felt by residents in Anderson Springs and local communities would not noticeably increase.
But many residents are skeptical.
“It’s terrifying,” said Susan Bartlett, who works as a new patient coordinator at the Pacific Fertility Center in San Francisco. “What’s happening to all these rocks that they’re busting into a million pieces?”
http://www.nytimes.com/2009/06/24/business/energy-environment/24geotherm.html 
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