DOE steps up on induced seismicity: New EGS safeguards in the works

In Washington, D.C., the Department of Energy will impose new safeguards on geothermal energy projects that include deep rock fracturing in order to mitigate earthquake risk, according to a recent report in the New York Times. The Times based the item on documents provided to it by the DOE.

Ground-motion sensors and other data will be monitored in accordance with the new requirements at all enhanced geothermal projects. In addition, an approved shut down plan will need to be in place in the event that earthquakes induced by fracturing processes are too powerful. Finally, according to the report, companies will have to file estimates of expected earthquake activity and submit project proposals for a review of the risks and the likelihood of success to outside experts.

The Times quoted Ernie Majer, a seismologist and deputy director of the Earth Science Division at Lawrence Berkeley National Laboratory in California, as saying the documents show that the department “is being ultra-careful about any induced seismicity.” The Department is clearly and properly trying to get in front of any potential hazards that might come with any enhanced geothermal systems projects.

The Times article continues to connect the closing of an AltaRock Energy project at The Geysers in California issues related to possible induced seismicity. But in December, AltaRock CEO Donald O’Shei told GD that the work on well E-7 at The Geysers associated with an earlier $6 million grant had been completed, thus it was stopped. The Times also said that “the company had refused to comment publicly” on the work stoppage at E-7, but you can see our interview with O’Shei and Chief Technology Officer Susan Petty on the topic here.

The new rules will clearly have an impact – albeit a minor one – on AltaRock’s upcoming project at the Newberry Volcano site in Oregon, for which the company received a new $25 million DOE grant. AltaRock will be required to monitor the site during its activities, which it intended to do anyway. There will likely be an increase in reporting to the DOE, as well as the submission of plans and expectations to outside experts. What is unclear is whether or not the last item will cause any delays in the work.

In our previous interview, Petty pointed out that volcanoes generally feature ring fractures around them, as is the case at the Newberry site. This localizes the regional stress field, which localizes any induced seismicity. That is, any populated areas outside the zone will face little to no risk of ground motion.

A final comment on the Times item. The newspaper continues to point to earthquakes caused by drilling. Drilling does not induce seismic activity. The fracturing process is what does this. It’s a rather small but important point and we believe that the Times is simply lumping all EGS work under the umbrella of drilling.