| Abstract |
At the Uenotai geothermal power station, the cooling waste water had been reinjected into underground through the reinjection Well F-1. Reinjection into Well F-1 started in February, 1993. After one and a half years (June,1995), the production well T-44, which was originally producing only steam from the feed zone located 250 meters away from the reinjection zone of Well F-1, started producing steam-water mixtures as the fluid enthalpy decreased, and the injection capacity of Well F-1 coincidentally increased about four times. These phenomena suggest subsurface interference between the two wells. On the basis of monitoring of stable isotopic ratios, fluid chemistry, and production history of Well T-44, a quantitative interpretation was made. |