H2s Dispersion Model at Cerro Prieto Geothermoelectric Power Plant

Abstract

The concentration levels of H2S in the atmosphere produced by the geothermal production activities at Cerro Prieto Geothermal power plant, located 30 km south to the city of Mexicali, Baja California, Mexico, are studied. By using the compilation and analysis of actual measured values of H2S concentration and utilizing a gaussian model of atmospheric dispersion, the expected levels of atmospheric H2S are estimated in seasonal terms, annually and its spatial distribution. These estimations are made to consider the effect of the installation of a new plant at different capacities on the populated areas close to the geothermal field, and in the work areas in the vicinity of the plants. According to an official announcement, this year will start the construction of a new plant of 100 MW capacity at Cerro Prieto in the area of the Ejido Hidalgo. It is concluded that the present and the expected levels of atmospheric H2S are not a risk for public health, in the populated towns near the geothermal field, assuming a risk treshold of 30 micrograms/kg (parts per billion). However there are work sites within the geothermal installations where expected levels are close to 300 parts per billion.