Amends the Clean Air Act to revise the definition of "renewable biomass" to include: (1) slash and precommercial sized thinnings harvested in environmentally sustainable quantities from National Forest System land or public land, other than components of the National Wilderness Preservation System, wilderness study areas, inventoried roadless areas and all unroaded areas of at least 5,000 acres, old growth stands, components of the National Landscape Conservation System, and national monuments; and (2) biomass obtained on land in any ownership from the immediate vicinity of any building, camp, or public infrastructure facility (including roads) at risk from wildfire.