Belo Monte Dam complex (including the now aborted Altamira Dam) in order to reach environmental sustainability over fossil fuel energy. Dams in Brazil emit high amounts of methane, due to the lush jungle covered by waters each year as the basin fills. Carbon is trapped by foliage, which then decays anaerobically with help from methanogens, converting the carbon to methane, which is a more potent greenhouse gas than carbon dioxide. As a result, carbon emissions are emitted from the dam each year it is in operation. A 1990 study of the Curuá-Una Dam, also in Brazil, found that it pollutes 3.5 times more in carbon dioxide equivalent than an oil power plant generating an equal amount of electricity would; not in the form of the atmospheric pollution associated with fossil fuel burning, but as the more dangerous methane emissions. Furthermore, the forest will be cleared before flooding of the area, so the and methane emissions calculated for the flooding of the forested area will be significantly undercut. In addition, a study on the Brazilian Tucuruí dam showed that the actual greenhouse gas emissions were a factor ten higher than its official calculations showed, and this dam is no exception; it is feared that the Belo Monte Dam calculations are also deliberately undercutting reality and that the flooding of its reservoir will create a similar situation. If the dam builders cleared the forest beforehand, they would remove the organic matter from the reservoir floor and the dam would produce less of the greenhouse gas methane. However, in the case of Tucuruí, only the economically necessary forest was cut (10%, near the opening to the spillway) and the rest was left intact to be flooded by the reservoir. The contractors had sold the logging rights to the flooded area, but found the plot unviable in the short amount of time they had allocated before the area was set to be flooded. This forest has been decaying under the water through Methanogenesis and producing large amounts of greenhouse gases. On the other hand, the energy generated by the dam for the next 50 years, at an average of 4419 MW, is 1.14 bboe (billion barrels of oil equivalent). This is approximately 9% of the proven oil reserves of Brazil (12.6 bbl), or 2% of the total oil reserves of Russia (60 bbl), or 5.5% of the proven oil reserves of the U.S. (21