The National Academies Press

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Pages 39-55

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From page 39... ... 2. Pages 5 arut 6: It is stated that "the HEDR Project has evidence that the necessary daily records no longer exist to allow detailed daily reconstruction for the period beginning 1950 through about 1953." The nature of the missing data, the "evidence" for this assertion, and what is available for this period are not clear. Read the entire page →
From page 40... ... . Hanford Site Annual Reports." Have the sources and accuracy of the annual reports been evaluated? Read the entire page →
From page 41... ... Unless the calculated values are supported by both recent and earlier monitoring data, the models will lack credibility. For that reason, early assessment of modeling results and comparison with measured data are crucial and would avoid premature publication of dose values that cannot be supported by the evidence. Read the entire page →
From page 42... ... at location 1, ci s/m3," "per d" should be 18. Section 2, Page 13: There is only one shielding factor. Read the entire page →
From page 43... ... were determined." The rest of the paragraph states that "either a self assessment or an informal solicitation of expert opinion was used to evaluate whether the maximum and minimum values as obtained from the literature should be changed to reflect physical limitations on parameter values and conditions present in the HEDR study region." Those procedures are appropriate, but some justification should be provided for the choices of values to reflect local conditions. Read the entire page →
From page 44... ... The normal distribution appears to be asymmetric and to have upper and lower bounds. The lognormal distribution also appears to have an upper bound. Read the entire page →
From page 45... ... , Page 1: The committee believes that the rainfall intensity and the chemical form of iodine-131, at least in rainfall, have a strong influence on the value of a. Also, as demonstrated in fallout near the Nevada test site, iodine-131 attached to large aerosols has a smaller value of ~ than molecular iodine. Read the entire page →
From page 46... ... Unless a sensitivity analysis indicates that expected seasonal (if not daily) and location variations in this quantity are not important for the assessment, the equation should be on the DES equation list and the parameter values selected accordingly. Read the entire page →
From page 47... ... 43. Section Swath As indicated in the text, the parameter value can vary as a result of the weather conditions, the crop under evaluation, and the chemical form of the radioisotope. Read the entire page →
From page 48... ... 50. Section HI DFrz For purposes of calculating external doses to the thyroid, much of the activity calculated for the root zone might actually be in the upper soil layer, inasmuch as nonirrigated land could provide the greatest contribution to the external dose. Read the entire page →
From page 49... ... The experimentally determined translocation factors for iodine that do exist are primarily from lea6-vegetation experiments, but they are not used, because it is assumed that all surface deposition is translocated to the edible fraction for lead vegetables and pasture grass. For grain and fruit, experimentally determined values do not seem to exist, but values were selected in this document. Read the entire page →
From page 50... ... The minimal and maximal values selected are very high and are not supported by the literature review that is presented. The high values do not seem to be the result of typographic errors (the same values are given in the appendix) Read the entire page →
From page 51... ... PNWD 2033: fodine-131 Releases from the Hanford Site, 1944 through �947 (Volumes and 2J This is an impressive two-volume document summarizing iodine releases for the critical early years of reactor operation. The release of 685 kCi of iodine-131 constitutes the most important airborne-source term. Read the entire page →
From page 52... ... A sensitivity analysis was not done, i.e., the HEDR project did not model how much different the results would be if plausible alternative distribution functions were used. Read the entire page →
From page 53... ... On the basis of fuel technology at the time, such releases were probably measurable, but the committee suspects that these releases were only small fractions of releases from fuel reprocessing. For completeness, in dose reconstruction there is the need to model direct reactor releases as continuous low-level releases, whereas the fuel-reprocessing releases need to be modeled as short-term episodic releases that occurred for a few hours or less. Read the entire page →
From page 54... ... 78. Page 2.6: In the second paragraph, one would expect to read that the selection of the values and the distributions of the release fractions appear "in the following section," but this information is not prowded until 30 pages later. Read the entire page →

From page 39...

... 2. Pages 5 arut 6: It is stated that "the HEDR Project has evidence that the necessary daily records no longer exist to allow detailed daily reconstruction for the period beginning 1950 through about 1953." The nature of the missing data, the "evidence" for this assertion, and what is available for this period are not clear.