Geothermal energy in the United States Geothermal Data System (NGDS). Through the NGDS, many older paper archives and drill logs that are stored at state geological surveys are now being digitized and made available for free to the public. The underground hot water and steam used to generate geothermal power may contain chemicals that could pollute the air and water if released at the surface. Hydrogen sulfide, which is toxic in high concentrations, is sometimes found in geothermal systems. Newer methods of generating geothermal power separate the hot steam collected underground from the steam used to power turbines, and substantially reduce the risk of releasing air-polluting
Songs from the Underground Songs from the Underground Songs from the Underground is the second extended play released to the public by American rock band Linkin Park. It features songs previously released through the Linkin Park Underground fan club, as well as two previously unreleased live tracks from Projekt Revolution. "Songs from the Underground" features numerous songs released through Linkin Park Underground, the band's official fan club, as well as two live tracks from Projekt Revolution 2008. "And One" and "Part of Me" were included in the "Hybrid Theory (EP)" (the band's first extended play), "Dedicated" was a demo originally released on "LP Underground