Environmental impact assessment Geopressure Subprogram

This environmental impact assessment (EIA) addresses the expected programmatic activities of the Geopressure Subprogram of the Division of Geothermal Energy. The goal of the Geopressure Subprogram is to stimulate development of geopressured resources as an economic, reliable, operationally safe, and environmentally acceptable energy source. The subprogram includes activities in the areas of engineering research and development; resource exploration, assessment, and development; resource utilization including pilot and demonstration facilities; and environmental research and control technology development. It should be recognized that most of the subprogram activities extend over several years and are in their early stages of implementation at this time. The zones of potential geopressure development are in the region located along the Texas and Louisiana Gulf Coasts extending up to 200 miles (300 km) inland. Geopressured zones are sedimentary basins where water is trapped at high pressures within or below thick, nearly impermeable shale sequences. The confined water supports most or all of the weight of the overburden. This inhibits sediment compaction and causes formation pore pressure to exceed hydrostatic pressure. in sedimentary basins that are underlain by thin oceanic crust, upward thermal conduction from the mantle heats geopressured fluids and sediments to abnormally high temperatures, often in excess of 260 C (500 F)