APPENDIX: ADDITIONAL SPECIFIC COMMENTS

A. PNWD-2227 HEDR

Page vi, line 1: “Measured doses that were previously published”—has there ever been any critical review of what is in all the various Hanford reports? The same concern arises at the top of p. 3.4 in relation to Hanford Site annual environmental monitoring reports.

Page viii, Conclusions: This section is so short that it is difficult to judge its accuracy. For example, “the most important contributors to dose were zinc-65 and phosphorus-32;” no justification was given in this section. The statement also ignores chemical form. There is also no justification of the most important means of exposure, the consumption of resident fish. It also ignores the American Indian differences in dose. Some brief, even one-line sentences might help.

Page viii, fifth bullet: It would be better to indicate the dose received by the maximum representative individual at Richland (presented in Figure S.1) than at Ringold, which has not been mentioned before. Also, the total estimated dose for 1944-1992 should be given.

Page viii, sixth bullet: It would be better to indicate the dose received by the typical representative individual at Richland than at Pasco, to compare with the maximum representative individual. Also, the total estimated dose for 1944-1992 should be given (instead of 1956-1965). In addition, the dose received by the occupational representative individual at Richland should be given.

Page 1.1, paragraph 1, last line: The committee recommends that the sentence read, “However, doses from the N reactor releases. . . . ” Otherwise, it might be difficult for the reader to understand why the N reactor is a factor, inasmuch as it is a closed water system.



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A REVIEW OF TWO HANFORD ENVIRONMENTAL DOSE RECONSTRUCTION PROJECT(HEDR) DOSIMETRY REPORTS: COLUMBIA RIVER PATHWAY AND ATMOSPHERICPATHWAY APPENDIX: ADDITIONAL SPECIFIC COMMENTS A. PNWD-2227 HEDR Page vi, line 1: “Measured doses that were previously published”—has there ever been any critical review of what is in all the various Hanford reports? The same concern arises at the top of p. 3.4 in relation to Hanford Site annual environmental monitoring reports. Page viii, Conclusions: This section is so short that it is difficult to judge its accuracy. For example, “the most important contributors to dose were zinc-65 and phosphorus-32;” no justification was given in this section. The statement also ignores chemical form. There is also no justification of the most important means of exposure, the consumption of resident fish. It also ignores the American Indian differences in dose. Some brief, even one-line sentences might help. Page viii, fifth bullet: It would be better to indicate the dose received by the maximum representative individual at Richland (presented in Figure S.1) than at Ringold, which has not been mentioned before. Also, the total estimated dose for 1944-1992 should be given. Page viii, sixth bullet: It would be better to indicate the dose received by the typical representative individual at Richland than at Pasco, to compare with the maximum representative individual. Also, the total estimated dose for 1944-1992 should be given (instead of 1956-1965). In addition, the dose received by the occupational representative individual at Richland should be given. Page 1.1, paragraph 1, last line: The committee recommends that the sentence read, “However, doses from the N reactor releases. . . . ” Otherwise, it might be difficult for the reader to understand why the N reactor is a factor, inasmuch as it is a closed water system.

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A REVIEW OF TWO HANFORD ENVIRONMENTAL DOSE RECONSTRUCTION PROJECT(HEDR) DOSIMETRY REPORTS: COLUMBIA RIVER PATHWAY AND ATMOSPHERICPATHWAY Page 1.2, Section 1.2: It is important to justify the use of only five radionuclides at this point. In fact, there seems to be some variation throughout the report in the number of radionuclides studied, from as few as two to nearly two dozen. That is confusing to the reader. Page 1.2, Section 1.2 line 3: It is wrong to indicate that doses were estimated for three types of representative individuals from 1944-1992; this was done only for 1950-1971. Page 1.2, Section 1.2: “ingestion of Willapa Bay shellfish and salmon and steelhead” — the main source of radionuclides noted later in the document is from resident, not anadromous fish and shellfish. This statement is therefore misleading (as is a similar statement on page v. in the summary). Page 3.1, paragraph 3: This long paragraph seems to say that models are required for two reasons: fish are not everywhere and radioactive measurements were below detection limits. When the obfuscation is taken out of this paragraph, it states that levels that low could not be measured and fishermen do not find fish everywhere. The paragraph could be improved. Page 3.3, paragraph 4: “If upon consideration, it is determined that any given pathway has the potential to add more than 5%. . . .” The editors need to work on this. This statement is very difficult to read. Page 3.5, paragraph 4: This is an excellent description, and the committee recommends that it appear earlier in the introduction or summary so that the reader can understand what went on in these reactors. Page 3.6, Section 3.1.1: Mechanical Source Term Model - last sentence on page 3.6 -paragraph 1: The statement made related to most of iodine-131 and neptunium-239 from natural uranium in river water needs explanation. How can there be much uranium in river water?

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A REVIEW OF TWO HANFORD ENVIRONMENTAL DOSE RECONSTRUCTION PROJECT(HEDR) DOSIMETRY REPORTS: COLUMBIA RIVER PATHWAY AND ATMOSPHERICPATHWAY Page 3.6, paragraph 2, last two sentences: It would be interesting to provide the released activity of iodine-131 that was due to fuel-element failures and to compare it with the total activity released into the atmosphere. Page 3.6, section 3.1.2: It would be useful to specify the physical half-lives of the five radionuclides in this section. Page 3.6, paragraph 4: “The amount of radionuclides released does not correlate to radiation dose.” This is an important fact and should, to some degree, be highlighted because later the model description states that the dose was related to what was in the fish, which was related to what was modeled in the water, which was related to the nature of the model. Page 3.7, Figures 3.2 and 3.3: A logarithmic scale would be more appropriate than a linear scale. Page 3.9, Figure 3.4: The scale is missing. Page 3.10, Section 3.2.2, second paragraph: The statement that some “comparisons are not as close” is disturbing. What does this mean? How close is “not as close?” A reference to another document “This sample is typical—further discussed in Walters (1994)” is not helpful. This needs to be addressed more fully. This sentence should be expanded into at least one paragraph in which the extent of the model validation is discussed and the essential results are presented. Page 3.13, Section 3.3.1, paragraph 3: “All BCF’s are for edible flesh and not whole fish.” However, some fish may be eaten with bones (smoked or pickled), and this would give very different results for some nuclides. How are they eaten by American Indians? Is fish made into stews or soups with bones included?

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A REVIEW OF TWO HANFORD ENVIRONMENTAL DOSE RECONSTRUCTION PROJECT(HEDR) DOSIMETRY REPORTS: COLUMBIA RIVER PATHWAY AND ATMOSPHERICPATHWAY Page 3.15, Table 3.1 and elsewhere: In addition to the medians, the ranges of the bioconcentration factors should be provided. When applicable, the probability density functions that were used for the uncertainty analysis should also be given. Page 3.18, Section 3.3.3: The report uses two methods of estimating doses from anadromous fish. One uses actual measurements, and the other treats salmon and steelhead as “resident” fish that spend their entire lives in the river, which supposedly yields an “upper limit for doses. ” Salmon feed little (steelhead do feed in freshwater) and are in the river for shorter periods than with resident fish. There is no justification for the “worst-case” assumptions and calculations. The committee recognizes that these calculations emphasize how small the river dose is; but bad science is never excusable. Also, the authors lump salmon and steelhead without considering their real differences in life cycle. The two species belong to the same genus (Onchorhynchus), but the Pacific salmon die after spawning, whereas the steelhead (anadromous rainbow trout) do not die. They live in the river for longer periods and must feed to stay alive. Again, because the dose is low, one cannot ignore biological reality (see also page 4.16, Section 4.3). The biggest missing factor is any discussion of the river pathway that are likely to be important with regard to American Indians, inasmuch as the river pathway is apt to be more important for these individuals than for any other groups. Page 3.24, first lines after Equations 3.9 and 3.10: Replace “effective organ dose” with “organ dose equivalent.” Page 3.29, Table 3.7: Some of the holdup times look very long. What is the basis for these estimates, and what variability is attached to them? Page 4.1, Section 4.0, paragraph 1: The uncertainty analysis needs to be expanded because it is unclear. The information in page 5.1, paragraph 2, should be partially introduced here. It is important to say that monthly estimates of concentrations incorporate statistical

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A REVIEW OF TWO HANFORD ENVIRONMENTAL DOSE RECONSTRUCTION PROJECT(HEDR) DOSIMETRY REPORTS: COLUMBIA RIVER PATHWAY AND ATMOSPHERICPATHWAY uncertainty in the release estimates and that this allows for stochastic modeling of radionuclide releases. In contrast, the Columbia River transport computer codes used and the computer river dosimetry were deterministic, using single monthly estimates without any statistical uncertainty. As a result, such techniques must be used to estimate the uncertainty and to estimate the sensitivity of the doses. Page 4.1, paragraph 5: “Less rigorous dose assessment techniques were used for the other time periods because radionuclide releases were much lower during those years.” If rigorous dose assessment was used, it should be based on good data. It should be even more important for “bad” or missing data sets. Page 4.2, Section 4.1.1: The radionuclides emitted during 1971-1992 were probably different from those discussed in this section. Even though their contribution to the total dose is trivial, they should be named here. Page 4.3: In this report, only two radionuclides were used as a rule: zinc-45 and phosphorus-32. But apparently as many as 19 were actually studied in some instances. There is little or no justification for this variation in the number of elements evaluated. No rationale is given for dropping individual radionuclides. This situation should be succinctly explained and corrected. Page 4.8: Figure 4.3 is not cited. Page 4.8, Section 4.1.5, last paragraph, last sentence: The results of the body-burden measurements of 5,099 children during 1965-1969 should be compared with the dose estimates in the preceding paragraph. Also, it would be interesting to derive dose estimates from the large number of body-burden measurements of Hanford workers from the 1950s and 1960s. The complete dose history does not mention that the American Indians have decidedly different eating habits from the so-called typical or maximum individual.

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A REVIEW OF TWO HANFORD ENVIRONMENTAL DOSE RECONSTRUCTION PROJECT(HEDR) DOSIMETRY REPORTS: COLUMBIA RIVER PATHWAY AND ATMOSPHERICPATHWAY Page 4.16: Figures 4.2 through 4.5 were supposed to be discussed here, but they were not. In addition, the pathways contributing to effective dose equivalents at Pasco are only vaguely described. The justification for saying that the largest contribution to effective dose equivalents came from neptunium-239, as well as zinc-65, arsenic-76, and sodium-24 is unclear. Unless the reader spends a lot of time studying these graphs and the data the figures are not informative. Page 4.17, paragraph 5: Were dose estimates from Table 4.5 based on the amount of material consumed? It should be made clear that the dose could be considerably higher if this was a constant food source, as it was for the American Indians. Page 5.2, paragraph 1: “Therefore, the uncertainty in water concentrations was estimated simply by propagating in a linear fashion the uncertainty in the monthly releases. . . .” Uncertainty is rarely linear, so this assumption seems unjustified. Page 5.5, paragraph 2: “Figure 5.2 is made up of contributions from several exposure pathways. . . .” Neither the figure nor this statement gives the reader any idea what the exposure pathways might be. Page 5.5, Section 5.1.3: The committee believes that sensitivity analysis should mention the causes of uncertainty. Page 5.15, Section 5.2.1: This section should be expanded with several tables and figures. The second paragraph in this section states, in line 1: “Concentration of radionuclides in water depends on both the source term and transport calculations.” Line 1 of the following paragraph states that the concentration of radionuclides in fish depends on the source term and transport estimates and the bioconcentration modeled in the CRD. There appears to be no control. The concentration in fish depends on the source term and transport estimates, which are themselves calculations; and the concentration of radionuclides in water depends on it. But it has already been determined that the concentration of radionuclides

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A REVIEW OF TWO HANFORD ENVIRONMENTAL DOSE RECONSTRUCTION PROJECT(HEDR) DOSIMETRY REPORTS: COLUMBIA RIVER PATHWAY AND ATMOSPHERICPATHWAY in fish is independent of the transport estimates. It seems that there is a problem with control here. Reference to measured radionuclide concentrations in fish would have helped to clarify this issue. Page 5.16, Section 5.2.2: It seems more logical to measure body burdens to validate the dose estimates obtained for the typical representative individual than to compare them with the doses calculated for an individual who would not consume any fish. In this way, at least the obvious discrepancies obtained before October 1963 (see Figures 5.11 and 5.12) would not be as glaring and the comparison would be more useful. B. PNWD-2228 HEDR Page 1.2, Figure 1.1: Although useful, this figure does not show several locations referred to in the text, e.g., Sunnyside, Wenatchee, and Ringold. Page 3.2, Figure 3.1: The title indicates releases; the ordinate label indicates release rates. Page 3.5, Section 3.2.2: “Surrogate data” needs explanation here. Page 3.7, paragraph 1: Why were meteorologic data only for 1944-1949 used for assessing all releases through 1972? Page 3.7, Section 3.3, paragraph 1: This section is confusing and misleading. It is stated that all calculations were based on backyard-source foodstuffs and that commercial distribution was not included. Later, the differences between backyard—commercial-source foods are calculated. Page 4.49, Section 4.3, paragraph 1: The decision to include releases for December 26-31, 1944, with those for January 1945 needs some elaboration. Is it correct to assume that the annual dose for 1945 also includes the dose for part of December 1944?

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A REVIEW OF TWO HANFORD ENVIRONMENTAL DOSE RECONSTRUCTION PROJECT(HEDR) DOSIMETRY REPORTS: COLUMBIA RIVER PATHWAY AND ATMOSPHERICPATHWAY Page 4.51, line 2 and elsewhere: The authors make statements like “Iodine-131 exposure was responsible for 99.8% of the dose to an adult. . . .” The dose from iodine-131 is largely to the thyroid, whereas doses from some other radionuclides irradiate bone marrow, total soft tissue, etc. One cannot compare the dose to one organ with doses to other organs or whole-body doses. (However, it is possible that the authors intended to say that 99.8% of the EDE was due to iodine-131, which would be more appropriate.) Page 4.51, paragraph 1: The statement related to plutonium-239 release implies very little plutonium release (11% x 0.025 of the original 1945 release). However, the statement that “Pu-239 was the next largest contributor” of airborne dose by 1965 could be misread and easily misinterpreted by the lay reader. Such a number could be misused. This section needs rewording. What was the form of Plutonium-239? Was it soluble or insoluble? Page 5.1, paragraph 1: The distinction between variability and uncertainty needs to be clearly discussed. Did the TSP also prepare a separate report on its findings? Page 5.1: When the authors write about uncertainty, the committee would expect an enumeration of the factors for which uncertainty was modeled. Instead, in paragraph 2, the authors enumerate the computer programs that generated the data, which does not help at all. Page 5.2: The explanation and example of the box-plot method are well done and should be very helpful to readers unfamiliar with it. Page 5.3, paragraph 2, sentence 1 (and page 6.1, last bullet): The authors’ way of stating the uncertainty (e.g., the 5-95% range is a factor of 25) makes it sound huge. The authors generally give the median estimate, and they might better say that the 5-95% range of uncertainty in thyroid doses was a factor of 5 around the estimate.

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A REVIEW OF TWO HANFORD ENVIRONMENTAL DOSE RECONSTRUCTION PROJECT(HEDR) DOSIMETRY REPORTS: COLUMBIA RIVER PATHWAY AND ATMOSPHERICPATHWAY Page 5.10, paragraph 2, sentence 2: Here and in another place, the authors mention that they performed regression analyses on “the ranks of the estimates and parameter,” but give no indication of how or why they did this or what the results were. Page 5.10, last paragraph, sentence 2: The authors indicate that the parameter contributing most to the uncertainty was the “individual ingestion dose conversion factor.” The committee finds this terminology unclear, in that it could refer to several component factors. If the authors mean “the amount of milk drunk,” then this should be stated. Page 5.11: The use of small pie charts on this page and elsewhere to show the relative importance of factors is an excellent idea. Page 6.1, first bullet: The authors initiate their conclusion by asserting that they have reconstructed “reliable. . . . doses.” However, the degree of certainty in the doses is not as great as the authors seem to imply. Page 6.2, last paragraph: A demonstration of validity is a key element of the whole project. The report refers to validation studies here, in its conclusion section, but does not mention validity in presenting results. This is a major gap in the report. Pages C.5-C.11: These tables need to indicate what the dose units are. Page 9, paragraph 2: Given the near-certain interest in the location and value of the highest estimated thyroid dose, the discussion is not clear. Do the locations “near Ringold” and “near Eltopia” really refer to the same place? (The location of Ringold is not shown in Figure 1.1.) Has the location of the highest median dose changed between the feasibility study and the final one? Page 10, Figures S.1 and S.2: The title indicates that the plotted values are doses (rems) whereas the ordinate label indicates that they are dose rates (rems per year). The annual

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A REVIEW OF TWO HANFORD ENVIRONMENTAL DOSE RECONSTRUCTION PROJECT(HEDR) DOSIMETRY REPORTS: COLUMBIA RIVER PATHWAY AND ATMOSPHERICPATHWAY average dose rate and the annual dose will have the same numerical value, but the inconsistency between the title and the axis label could be confusing. Page A.2, Table A.1: The descriptions of the changes in atmospheric transport and environmental accumulation do not fit the methods used in the feasibility study. Page A.3, last paragraph: The term “loss of correlation effects that existed in the feasibility study ” is confusing. Were correlation effects considered in the feasibility study but not in this one? What correlation effects were important to the results? Page B.6, last paragraph: What models were used for calculating wet and dry deposition? Were fixed values used for each material category? How do the depositions calculated with RATCHET compare with those calculated with MESOILT2? Page B.7, Section B.2.4., paragraph 2: Was a dynamic model used to calculate the partitioning of the iodine species, or was the fraction fixed for all distances for all realizations? Page D.5 ff. The name of the special unit of activity (curie) should not be used as a synonym for the name of the quantity (activity) itself.