Photo by AP Wide World A proposed EPA rule calls for a 30% reduction in greenhouse gas emissions below 2005 levels by 2030. States would be responsible for implementing plans by June 2016. Related Links: EPA Sets Ambitious Goal to Cut Existing Powerplants' CO2 Emissions Text of EPA Proposal (June 2) The U.S. Environmental Protection Agency unveiled a proposal to reduce greenhouse gas emissions from existing powerplants, calling for a 30% reduction below 2005 levels by 2030. EPA says the proposed rule, which it released on June 2, could lead to upgrades at fossil-fuel-fired powerplants and has the potential to
Arch dams, classically curved monoliths situated in narrow valleys, are not as common as other types of dams, such as embankment dams and gravity dams. ENR takes a look at some of the biggest arch dams in the world, both completed and under construction.