The Bush administration and Federal Reserve Chair Alan Greenspan are expressing increasing concerns about dwindling natural gas supplies, a move that environmentalists see as a ploy to drum up support for nuclear energy and drilling on public lands. The concern over natural gas comes as Congress debates a comprehensive energy bill that could include provisions for drilling on federal lands in Colorado, Utah, and New Mexico, as well as offshore in both oceans and the Gulf of Mexico. Patricio Silva, a lawyer for the Natural Resources Defense Council, called the warnings about limited natural gas resources opportunistic: “We suspect this is definitely meant to influence the debate over access [to public lands].” Meanwhile, Greenspan also expressed support for expanding the nation’s nuclear power capacity, a position that was backed by the Senate yesterday in a 50-48 vote to retain in the energy bill new federal loan guarantees for the construction of nuclear plants.