Reuters: The Obama administration is expected to announce by Wednesday its updated plan for oil and natural gas drilling in U.S. waters, including whether to allow exploration for the first time along the U.S. East Coast. The plan could pave the way for a significant new domestic source of energy, helping to reduce U.S. dependence on oil imports and boost supplies of natural gas used to displace coal in power plants as the country works to reduce emissions of climate-changing greenhouse …