This final action withdraws the conditional exclusion from regulations promulgated on December 19, 2008 under subtitle C of the Resource Conservation and Recovery Act (RCRA) for so-called Emission Comparable Fuel (ECF). These are fuels produced from hazardous secondary materials which, when burned in industrial boilers under specified conditions, generate emissions that are comparable to emissions from burning fuel oil in those boilers. EPA is withdrawing this conditional exclusion because the Agency has concluded that ECF is more appropriately classified as a discarded material and regulated as a hazardous waste. The exclusions for comparable fuel and synthesis gas fuel are not addressed or otherwise affected by this final rule.