Project Overview |
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The purpose of HEDR was to estimate radiation doses since the first year of Hanford operations, that people could have received as a result of radionuclide emissions from the Hanford Site. Exposures to radioactive materials released to the atmosphere resulted primarily from the consumption of food containing radioactivity, inhalation of contaminated air, or direct exposure to radioactivity in soil or air. Initial study efforts indicated that atmospheric doses resulting from exposures to surface, irrigation and drinking waters were minor in comparison to other exposure routes, therefore, they were not studied in detail. The greatest contributors to dose from the atmospheric pathway were the chemical separation plants that began operations on December 26, 1944 (because there were only 6 days of separation plant operations in 1944, the data from those days have been attributed to 1945). Major separation plant activities ceased in November 1972. The PUREX (plutonium/uranium extraction) plant did operate for a limited time in the late 1980s. Once the last chemical separation plant ceased operations, radioactive releases to the atmosphere decreased dramatically. Consequently, detailed studies began for estimating doses in the years 1944-1972. Because of the lower radioactive releases after 1972, the doses published in the Hanford annual environmental report were used to complete the dose history for the period of 1973-1992. Dose estimates prior to 1973 were calculated for representative individuals in a 75,000 square-mile area surrounding the Hanford Site, including eastern Washington, northeastern Oregon, and western Idaho. Each estimate was the median (middle value) of a distribution sorted by increasing size of its values. Each distribution, consisting of 100 values, was determined using a "Monte Carlo" statistical sampling technique. Doses from iodine-131 and five other radionuclides account for 99% of the potential dose from the atmospheric pathways. The other radionuclides are strontium-90, ruthenium-103, ruthenium-106, cerium-144, and plutonium-239. These doses are estimated in terms of effective dose equivalent (EDE), a measure of dose that attributes weighting factors to body organs and tissues, to produce an estimate of total risk from exposure to multiple radionuclides. EDE is reported in units of "rem" ("roentgen equivalent man"). |
Phase 1 Document Collection (Prototype Dose Reconstruction Project) |
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The
Hanford National Laboratory Searchable Bibliographic Database
(Now labelled: Hanford Thyroid Disease Study (HTDS))
Archived version of page For further information see: Project Profiles - Hanford Archived version of page Combined Annotated Bibliography July 1988 - May 1994 Phase 1 of the Hanford Environmental Dose Reconstruction Project Phase 1 of the Hanford Environmental Dose Reconstruction Project Effects of the loss of correlation structure on Phase 1 dose estimates. Atmospheric transport modeling and input data for Phase 1 Population estimates for Phase 1 Selection of Dominant Radionuclides for Phase 1 Hanford Environmental Bibliography Hanford Environmental Dose Reconstruction Project Record Databases |
Data File Sets |
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Last modified: October 3, 2008