US EPA has withdrawn the Emission Comparable Fuels (ECF) Rule, a rule that was finalized in December 2008. The rule sought to remove regulatory costs by reclassifying fuels that would otherwise be regulated as hazardous waste, but generate emissions similar to fuel oil when burned.
As in, the Bush Administration allowed boilers to burn hazardous waste without a hazardous waste permit or proper air pollution controls. It was a terrible exemption from classic air pollution control rules and regulations coming at the end of the Bush Administration.
EPA has now withdrawn the rule due to difficulty of ensuring that emissions from burning ECF are comparable to emissions from burning fuel oil. The ECF rule was criticized for potentially allowing hazardous waste to evade the hazardous waste regulatory system, and for being difficult to administer. Industry members have also criticized it because of the detailed conditions for reclassification, which they believe will limit the rule’s use.
More information on the rule: http://www.epa.gov/epawaste/hazard/tsd/td/combust/compfuels/exclusion.htm