FAQ #4: Will any water that you inject or produce enter the local or regional aquifers?
No. Water injected into the well will not connect to local groundwater resources. The existing demonstration well is cased and cemented into the ground for the first 6,500 feet below the surface with multiple layers of steel and cement as required by the highest standards of groundwater protection. The planned EGS reservoir will be created 6,500 to 11,000 feet below the ground surface, a vertical mile below the shallow groundwater aquifer in a thick section of impermeable rock.
An extensive array of seismometers and a temperature sensing fiber optic cable installed in the well will help monitor EGS reservoir growth and movement in the subsurface (see FAQ #6). If too much upward growth is observed, the stimulation will be halted in that zone and started at a deeper zone. An independent review of potential hydrologic impacts can be found here.
Previous FAQ: How much water will be used and where will you get it?