Nick SnowWashington EditorIn a remarkable contrast to the usual congressional hearing that describes problems with a regulation's implementation or enforcement, a US Senate Environment and Public Works subcommittee recently heard about one where the federal government apparently is getting things right.The 2005 Diesel Emissions Reduction Act (DERA) is working not because Congress imposed a mandate on the US Environmental Protection Agency, but because it authorized $200 million/year to facilitate voluntary incentives that have attracted support from more than 600 groups and organizations, the Clean Air and Nuclear Safety Subcommittee was told on May 12."DERA has improved America's ai...