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Geothermal Project – Drillhead
Image by Kecko
With such a drillhead the amazing depth of 4450 m was reached. In the hope to find hot water of 150-200 degrees Celsius at a depth of 4000-4500 m. But instead of water, only gas was found, that almost has blown up the plant. St. Gallen, Switzerland, July 21, 2013.
Geothermal Project – Gas Alert
Image by Kecko
A gas leak resulted in a dangerous increase of the pressure in the wellbore. As a countermeasure, 650 cubic meters of water and heavy drilling fluid was pumped into the hole. This caused an earthquake of Saturday morning, with the strength of 3.6 magnitude. According to the Seismological Service, the earthquake was noticeable in a radius of 75 km. But the pressure was successfully reduced. St. Gallen, Switzerland, July 21, 2013.