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Community MonitoringCommitmentCommitment to Monitor and Report Environmental RadioactivityLANL will provide monitoring systems to assure that, according to the best available science, not one member of the public, statewide, is likely to be harmed by radiation or radioactive material from LANL. Scientific Discussion According to the best available science "the population weighted average lifetime excess risk of death from cancer following an acute dose equivalent of 10 rem is estimated to be 0.8%"1 . In other words, if 100,000 people each receive 10 rem, the collective dose is 1 million person-rem, and 800 excess cancer deaths would be expected. For chronic doses, this estimate is often reduced by a factor of two. The results of small chronic doses accumulated over a lifetime are too small to measure. Nevertheless, some government agencies assume a linear, no-threshold model and estimate that a collective dose of 1 person-rem may result in a risk of 8E-4 per rem. For chronic doses, this estimate is usually reduced to 5E-4 per rem. As a goal, a lifetime risk of 1E-5 is desirable, which corresponds to a lifetime dose of 20 mrem; this corresponds to 0.4 mrem/year accumulated over 50 years. To meet this goal, the LANL's air quality Dose-Assessment team will assess each individual pathway (air, water, soil, food, and direct radiation) with an accuracy of 0.1 mrem/year and report the results in the annual report "Environmental Surveillance at Los Alamos." Reference 1. "Health Effects of Exposure to Low Levels of Ionizing Radiation, BEIR V," (page 6) ISBN 0-309-03995-9, Committee on the Biological Effects of Ionizing Radiation, National Academy Press, Washington, D.C., 1990. FirewoodFirewood DistributionLANL's trees and soil have been characterized for potential contamination, and the relevant human exposure pathways have been evaluated. There are no detectable health risks. The distribution of firewood is subject to the "Procedure for Identification, Removal, and Disposition of Potentially Contaminated Trees from Los Alamos National Laboratory Technical Areas," LA-UR-01-6855. According to the procedure, all potentially contaminated trees are retained on LANL property. We have measured the potential contamination in LANL trees; the most recent LANL report, LA-UR-01-6157, is enclosed. Note, the highest concentrations of contamination occur in wood ash. For example, David Englert (NMED OB) measured about 10 pCi/g of cesium-137 in Cerro Grande fire ash, which is in general agreement with the data obtained by LANL. The ashing process concentrates some elements by up to a factor of 250. Cesium-137 concentrations in wood from global fallout are on the order of 0.1 pCi/g (dry weight), so concentrations in ash of 20 to 30 pCi/g from fallout are routinely encountered, worldwide. Wood ash is often spread on agricultural land as a potassium fertilizer and also to raise the pH of acidic soil, though this practice is less common in New Mexico because the soil is usually alkaline. An upper limit is 1 ton of wood ash per acre of farm land. When tilled to a depth of 6 inches, this results in a dilution of a factor of 1,000, i.e., ash with a concentration of 10 pCi/g results in a soil concentration of 0.01 pCi/g. The resulting dose calculated for a residential farmer scenario is 0.01 mrem/year from cesium-137 at 10 pCi/g ash. A residential gardener is unlikely to use more than 100 pounds of ash, so in this case the dose will be much smaller. The following table summarizes the concentrations and potential doses from other radionuclides. The wood-ash concentrations are the highest of (a) the reference values from LA-UR-01-6157, (b) the IFRAT report, and (c) David Englert's data.
We have also calculated the dose from cutting, splitting, and carrying the wood; inhaling the wood smoke; carrying and inhaling the ash; and sitting near the ash while it is in storage. In each case, the dose is smaller than in the table. To summarize:
FAQsFrequently Asked QuestionsIs contaminated water flowing into the Rio Grande? Yes, but the amounts of contamination are far too small to be a health hazard to anyone. For more information, please refer to Chapter 3 of the report "Environmental Surveillance at Los Alamos during 2001," LA-13979-ENV | Excerpt of Chapter 3 (pdf). Were we affected by smoke from the Cerro Grande fire? Yes, smoke is a significant health hazard. However, the Cerro Grande fire smoke was like the smoke from any other forest fire. Please refer to the Cerro Grande Fire Risk Assessment Corporation's Independent Risk Assessment for more information. I grow medicinal herbs. Are they safe? Yes. For more information, please refer to Chapter 3 of the report "Environmental Surveillance at Los Alamos during 2001," LA-13979-ENV | Excerpt of Chapter 3 (pdf). What are the larger issues related to LANL air quality? We consistently put all relevant data, facts, and reports on the Air Quality web site. What are the statistics on health effects? All contaminants affect Los Alamos residents more than anyone else, and LANL does not affect the health of Los Alamos residents. For more information, please view the presentation "Cancer Trends in Los Alamos County, 1973-1997" (ppt). What are AIRNET and DPRNET? AIRNET measures extremely small amounts of radioactive material in the air, but we have to wait six months for the results. DPRNET measures gamma and neutron radiation. Gamma radiation from LANL is too small to distinguish from natural radiation. Neutron data can be detected up to 0.3 kilometers from LANL, but we have to wait six months for the results. Will LANL commit to provide air monitoring systems? LANL is committed to provide monitoring systems that will assure that, according to the best available science, not one member of the public, statewide, is likely to be harmed by radiation or radioactive material from LANL. Will LANL provide equipment? LANL will provide the best-available technology to meet the commitment in Section 8. What about the wood cut after the Cerro Grande fire? Is it safe? Yes. Please see the firewood tab for information on firewood distribution. Can LANL provide training? Yes. For an example, please view our course on Environmental Radioactivity (pdf). Is there a comprehensive education program? Some courses exist at Northern New Mexico Community College and the University of New Mexico - Los Alamos; others can be established according to the demand: live or self study; with college credit or without, several hours or semesters. What about water and ash? The water and ash are safe. Refer to Section 11 of the IFRAT report. Where can we find data to establish a baseline? LANL's Air Quality web site has extensive data available. Are the food pathways safe? Yes. For more information, please refer to Chapter 3 of the report "Environmental Surveillance at Los Alamos during 2001," LA-13979-ENV | Excerpt of Chapter 3 (pdf). What are the health effects? According to the best available science, there are no health effects. For more information, please refer to Chapter 3 of the report "Environmenal Surveillance at Los Alamos during 2001," LA-13979-ENV | Excerpt of Chapter 3 (pdf). ESRsEnvironmental Surveillance ReportsThese annual reports summarize environmental data that comply with applicable federal, state, and local environmental laws and regulations, Executive Orders, and DOE policies. Additional data, beyond the minimum required, are gathered and reported as part of the Laboratory's efforts to ensure public safety and to monitor environmental quality at and near the Laboratory.
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