In March, 2019, the two new vertical wells for monitoring were completed. The shallow well (68-32) was drilled to 970 ft depth, penetrating alluvial sands and gravel. The deeper well (78-32) was drilled to about 3300 ft depth, having intersected the contact with granitic basement rock aroun d 2600 ft depth. Both wells were instrumented with state-of-the-art sensors. Two borehole seismometers were installed into the bottom of well 68-32, whereas an optoelectronic Distributed Acoustic Sensor (DAS) cable was installed into well 78-32.
During the drilling of 78-32, an aquifer test was performed, which proved production of 46°C water from about 700-900 ft depth at 200 gallons per minute. This warm water represents subsurface outflow from Roosevelt Hot Springs, and it is non-potable due to high TDS, making it ideal for future use at the Utah FORGE project.
In April the stimulation phase was completed with great success. Injection tests were run at three distinct depth intervals in the reservoir granite; the first was in the open-hole section, whereas the other two were at slightly higher level within the cased section of the well.
During these tests, fluid flow and fracture opening were detected by both the Schlumberger geophone string array and the DAS cable in well 78-32. Televiewer logs were run in the open-hole section of 58-32 to assess the injection test effects. All of the data are now being processed.