[en] The Waste Isolation Pilot Plant (WIPP), a repository for defense transuranic (TRU) waste, was built and is operated by the U.S. Department of Energy (DOE). The WIPP Land Withdrawal Act (LWA) required initial certification of compliance of the WIPP by the U.S. Environmental Protection Agency (EPA). In addition, a recertification decision is required by the LWA every five years, dated from the initial receipt of TRU waste. The first TRU waste shipment arrived at the WIPP on March 26, 1999, and therefore the first recertification application is due from DOE to EPA by March 25, 2004. The Environmental Evaluation Group (EEG) provides technical oversight of the WIPP project on behalf of the State of New Mexico. The EEG considers the first recertification as a precedent setting event. Therefore, the EEG began the identification of recertification issues immediately following the initial certification decision. These issues have evolved since that time, based on discussions with the DOE and EEG's understanding of DOE's ongoing research. Performance assessment is required by the EPA certification and its results are needed to determine whether the facility remains in compliance at the time of the recertification application. The DOE must submit periodic change reports to the EPA which summarize activities and conditions that differ from the compliance application. Also, the EPA may request additional information from the DOE that may pertain to continued compliance. These changes and new information must be considered for recertification performance assessment