In 1987, the U.S. Departmentof Energy (DOE) directedthe Pacific Northwest Laboratory, J operatedby Battelle Memorial Institute, to conduct the HartfordEnvironmentalDose Reconstruction 0tEDR) Project. The DOE directive to begin project work followed a recommendationby the HanfordHealth Effects Review (HHER) Panel in 1986. The HHER Panel was formed to consider • the potential health implications of past releases of radioactivematerials from the HartfordSite near Richland, Washington. Membersof a Technical Steering Panel (TSP) were selected to direct the project work. The TSP consists of experts in the various technical fields relevant to HEDR Project work and representativesfrom the states of Washington, Oregon, and Idaho; Native American Tribes; and the public. The technical members of the panel were selected by the vice presidents for research at major universities in Washington and Oregon. The state representativeswere selected by the respective state governments. The Native American tribes and public representatives were selected by the other panel members. A December 1990 Memorandumof Understandingbetween the Secretariesof the DOE and the U.S. Departmentof Health and Human Services (DHHS) transferredresponsibility for managing the DOE's dose reconstructionand exposure assessment studies to the DHHS. This transfer resulted in the current contract between Battelle, Pacific Northwest Laboratories(BNW) and the Centers for Disease Control and Prevention (CDC), an agency of the DHHS, to continuethe project. The purpose of the HEDR Project is to estimatethe radiationdose that individualscould have received as a result of emissions since 1944 from the HartfordSite. The HEDR Project work is conducted under several technical and administrative tasks, among which are the Technical Integration and Statistics Tasks. The staff on these tasks provide the _cal guidance, coordination, and communicationamong other technical tasks, as well as ensuring the appropriateuse of statistics and statisticalmethods. These efforts include the model reliability analysis, a shared activity between the two tasks. Model reliability involves the review of concepts, testing of the implementationof models in computercodes, uncertaintyand sensitivity analyses, and validation of model output. Validation of the model output is part of the analysis of the various models. A HEDR Model Validation Plan has been published (Napier 1993). The model validation results reported in this document are the implementationof the model validation plan and fulfdl the requirements of Milestone 0204C. This reporthad been planned as a component of a HEDR Model Reliability Report, Milestone 0803B. The publicationof the validationinformationwas accelerated as a separate milestone at the request of the TSP. The other model reliability informationwill be reported in the code documentationand the dose reports. q, This report completes HEDR Project Milestone 0204C. It is the final report, replacingthe previous version dated January 1994. Appendix E is a record of the TSP co...