Abstract: A power plant operating on geothermal steam containing more than about 5% non-condensable gases includes a topping steam turbine for expanding the steam to produce power and from which exhaust steam is extracted at a pressure above atmospheric pressure, and an indirect contact heat exchanger containing clean water for condensing the exhaust steam at a pressure above atmospheric pressure to produce geothermal steam condensate, and for consequently vaporizing the clean water to produce clean steam. The non-condensable gases contained in the geothermal steam are extracted from the heat exchanger and, being at a pressure above atmospheric pressure, can be injected, without being further pressurized, directly into the ground. The clean steam produced by the heat exchanger is applied to a bottoming steam turbine which expands the clean steam to produce power and from which clean exhaust steam is extracted.