In December 2008, the US EPA excluded certain fuels derived from hazardous secondary materials which, when burned in industrial boilers under specified conditions generated air pollutant emissions comparable to those produced by burning fuel oil in those boilers. The 2008 conditional exclusion provided a regulatory compliance break for industrial facilities that were able to use potentially hazardous secondary materials as fuel in their boilers since they could do so without the burden of full RCRA documentation on the materials burned. They also, of course, saved money on fuel oil, and on disposal costs of the secondary materials if not burned.

On June 8th, the agency changed its mind, and determined that these secondary materials that could be used a s fuels need to be classified as hazardous wastes