This action will address the agency's residual risk and technology review (RTR) of the National Emission Standards for Hazardous Air Pollutants (NESHAP) for Plywood and Composite Wood Products (PCWP). The PCWP NESHAP, subpart DDDD, was promulgated pursuant to section 112(d) of the Clean Air Act (CAA) on July 30, 2004, and was amended on February 16, 2006 and October 29, 2007. The NESHAP established emission limitations and work practice requirements based on maximum achievable controlling technology (MACT) for controlling emissions of hazardous air pollutants (HAP) from PCWP. The HAP emitted from lumber dry kilns and plywood, particleboard, medium density fiberboard, hardboard, (structural) fiberboard, oriented strand board (OSB) and engineered wood products manufacturing processes include formaldehyde, methanol, acetaldehyde, acrolein, phenol and propionaldehyde. This action will implement the residual risk review requirements of CAA section 112(f)(2) and the technology review requirements of CAA section 112(d)(6). The statute directs the EPA to promulgate emission standards under CAA 112(f)(2) if such standards are required to provide an ample margin of safety to protect public health or to prevent, taking relevant factors into account, an adverse environmental effect. Any such standards are to be promulgated within 8 years after promulgation of MACT standards under CAA section 112(d). CAA section 112(d)(6) requires the EPA to review and revise the MACT standards as necessary, taking into account developments in practices, processes and control technologies, no less often than every 8 years. Pursuant to a court order, the EPA is obligated to complete the final action by June 30, 2020. In addition, this rulemaking will further respond to the 2007 remand by the U.S. Court of Appeals of the original MACT standards.