Committee rosters are set, oversight plans are signed and witnesses are being called up to the Hill. For congressional Republicans, it's regulation-hunting season. Republicans have made no secret of their plans to swipe at what they've deemed an overly burdensome environmental agenda from the Obama administration, and the change in power in the Senate provides both some new turf and leverage to do it. That effort kicked off in earnest Feb. 4, 2015 when the House Transportation and Infrastructure and Senate Environment and Public Works committees teamed up for a joint hearing to grill Environmental Protection Agency Administrator Gina McCarthy on the agency's proposed expansion of its Clean Water Act authority.