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Extension of UCRL-50936 (13 case studies) as requested by PNE, USAEC

Description: This report provides a reassessment of the Kra Canal Project as prepared in December 1972. This reassessment differs in that thirty- four salvos with a total yield of about 170 MT were assumed; acceptable firing days were selected from actual meteorological data when the winds at all levels up to the expected debris cloud top blew toward the west plus or minus thirty degrees; and the lead in the devices was assumed to be from monazite sand. The doses are considerably less than those estimated in the earlier assessment.
Date: January 29, 1973
Creator: Peterson, K. R.
Partner: UNT Libraries Government Documents Department

Extension of UCRL-50936 (13 case studies) as requested by PNE, USAEC

Description: This report contains a reassessment of the Kra Canal Project. This latest assessment differs from the original study in that: Thirty- four salvos with a total yield of about 170 MT were assumed; `Acceptable` firing days were selected from actual meteorological data when the winds at all levels up to the expected debris cloud top blew toward the west, +/- 30 degrees; and the lead in the devices was assumed to be from monazite sand. The doses are considerably less than those estimated in the earlier report. The reasons for this are: A longer trajectory to Sumatra was assumed such that the debris clouds traveled 1600 Km before crossing the west coast of Sumatra; Residents of the Nicobar Islands and Sumatra to our knowledge do not consume milk, hence the forage-cow-milk pathway is not included; The use of lead from monazite sands reduced the total dose; Some of the latest dose conversion constants used are smaller than those in the earlier report; and the effects of precipitation scavenging were based on an improved assessment.
Date: January 29, 1973
Creator: Batzel, R. E.
Partner: UNT Libraries Government Documents Department

Preliminary I-129 measurements in the SRP environs

Description: Recently a preliminary program at Savannah River Plant was began to measure I-129 concentrations in a variety of environmental samples. The objectives of the study were three-fold: First, to at least qualitatively estimate the impact of Savannah River Plant (SRP) operations on the I-129 inventory in the surrounding area; second, to determine prominent pathways of I-129 to man and to obtain, where possible, estimates of their associated dose rates; and third, to provide necessary input data to help in the design and implementation of more comprehensive follow-up studies.
Date: January 23, 1976
Creator: Hochel, R. C.
Partner: UNT Libraries Government Documents Department

Improved method for calculation of population doses from nuclear complexes over large geographical areas. [Dose to population of entire contiguous U. S. from releases from the Hanford facilities]

Description: To simplify the calculation of potential long-distance environmental impacts, an overall average population exposure coefficient (P.E.C.) for the entire contiguous United States was calculated for releases to the atmosphere from Hanford facilities. The method, requiring machine computation, combines Bureau of Census population data by census enumeration district and an annual average atmospheric dilution factor (anti chi/Q') derived from 12-hourly gridded wind analyses provided by the NOAA's National Meteorological Center. A variable-trajectory puff-advection model was used to calculate an hourly anti chi/Q' for each grid square, assuming uniform hourly releases; seasonal and annual averages were then calculated. For Hanford, using 1970 census data, a P.E.C. of 2 x 10/sup -3/ man-seconds per cubic meter was calculated. The P.E.C. is useful for both radioactive and nonradioactive releases. To calculate population doses for the entire contiguous United States, the P.E.C. is multiplied by the annual average release rate and then by the dose factor (rem/yr per Ci/m/sup 3/) for each radionuclide, and the dose contribution in man-rem is summed for all radionuclides. For multiple pathways, the P.E.C. is still useful, provided that doses from a unit release can be obtained from a set of atmospheric dose factors. The methodology is applicable to any point source, any set of population data by map grid coordinates, and any geographical area covered by equivalent meteorological data.
Date: September 1, 1977
Creator: Corley, J P; Baker, D A; Hill, E R & Wendell, L L
Partner: UNT Libraries Government Documents Department

Environmental radiological surveillance in perspective: the relative importance of environmental media as a function of effluent pathway and radionuclides

Description: Most published guidelines for environmental surveillance emphasize the collection and analysis of specific media (e.g. air, water, milk, direct radiation) without total regard for the potential dose impact of the radionuclides expected in or actually present in the effluent streams from nuclear facilities. To determine the relative importance of medium/nuclide combinations in environmental surveillance, the experience at major ERDA sites and at operating nuclear power plants was reviewed. Typical release rates for nuclide groupings (tritium, noble gases, radioiodine, mixed fission or activation products, and transuranics) in those effluent streams were followed through various environmental pathways. By using this scheme the environmental medium which is most prominent in the critical dose pathway to man was determined. It was also possible to determine points of short-or long-term contaminant accumulation. Following these combination providing the relative importance of sampling specific environmental media with emphasis on the radiation dose to a critical population group. Finally, the results of these environmental pathway studies are presented in tabular form to provide ready reference for environmental surveillance program design or evaluation.
Date: October 1, 1977
Creator: Denham, D. H.
Partner: UNT Libraries Government Documents Department

Anticipated radiological impacts from the mining and milling of thorium for the nonproliferative fuels. [Dose commitments to individuals and populations from inhalation or ingestion of thorium-cycle-related radionuclides]

Description: Recent emphasis on proliferation-resistant fuel cycles utilizing thorium--uranium-233 fuels has necessitated evaluation of the potential radiological impact of mining and milling thorium ore. Therefore, an analysis has been completed of hypothetical mine-mill complexes using population and meteorological data representative of a thorium resource site in the Lemhi Pass area of Idaho/Montana, United States of America. Source terms for the site include thorium-232 decay chain radionuclides suspended as dusts and radon-220 and daughters initially released as gas. Fifty-year dose commitments to maximally exposed individuals of 2.4 mrem to total body, 9.5 mrem to bone, and 35 mrem to lungs are calculated to result from facility operation. Radium-228, thorium-228, thorium-232 and lead-212 (daughter of radon-220) are found to be the principal contributors to dose. General population doses for a 50-mile radius surrounding the facility are estimated to be 0.05 man-rem to total body, 0.1 man-rem to bone, and 0.7 man-rem to lungs. Generally speaking, the results of this study indicate that the radiological aspects of thorium mining and milling should pose no significant problems with regard to implementation of thorium fuel cycles.
Date: January 1, 1978
Creator: Meyer, H.R. & Till, J.E.
Partner: UNT Libraries Government Documents Department

Environmentally important radionuclides in nonproliferative fuel cycles. [/sup 3/H, /sup 14/C, /sup 99/Tc, and /sup 232/U]

Description: Our analyses indicate that more in-depth research should be done on /sup 3/H, /sup 14/C, /sup 99/Tc, and /sup 232/U, especially because of their presence in nonproliferative fuel cycles. For increased /sup 3/H production by fast reactors, we can only speculate that such research could show that environmental releases might be significantly greater than for LWRs. Carbon-14 will likely not be a problem if a suitable decontamination factor can be agreed upon for reprocessing facilities and if a satisfactory regulatory limit can be established for global populations. Additional experimental research is urgently needed to determine the uptake of low levels of /sup 99/Tc by plants. These data are essential before an accurate assessment of /sup 99/Tc releases can be made. Finally, we recommend that investigators take a closer look at the potential problems associated with /sup 232/U and daughters. This radionuclide could contribute a significant portion of the dose in both environmental and occupational exposures from the nonproliferative fuels.
Date: January 1, 1978
Creator: Kaye, S.V. & Till, J.E.
Partner: UNT Libraries Government Documents Department

Assessment of /sup 99/Tc releases to the atmosphere: a plea for applied research. [Dose to man through food chain concentration]

Description: Recent experimental data suggest that the concentration factor for uptake of /sup 99/Tc by vegetation from soils may be two to three orders of magnitude higher than the 0.25 value currently being used in radiological assessments. Following a survey of the literature, a concentration factor of 50 was applied to evaluate the dose from a 1.0 Ci/year release to the atmosphere by a hypothetical uranium enrichment facility. Doses to the GI tract and thyroid of an adult living 1600 m from the facility were 18 millirems and 80 millirems, respectively. These doses are delivered entirely through transport of /sup 99/Tc through food chain pathways. This assessment indicates a potential for /sup 99/Tc exposures to exceed recently proposed standards of the U.S. Environmental Protection Agency in 40 CFR 190. The previously assumed concentration factor of 0.25 would have produced corresponding doses of 0.13 millirem to the GI tract and 0.57 millirem to the thyroid. The results of this analysis demonstrate the need for additional research on the environmental behavior and dosimetry of /sup 99/Tc. In particular, data are needed to elucidate the retention of /sup 99/Tc in soils and the uptake of /sup 99/Tc by edible vegetation in field studies of chronic exposure conditions. Data on the uptake and retention of /sup 99/Tc in humans are also necessary to improve the reliability of dose conversion factors for specific organs and various age groups.
Date: June 1, 1978
Creator: Till, J.E.; Hoffman, F.O. & Dunning, D.E. Jr.
Partner: UNT Libraries Government Documents Department

Review of biological monitoring programs at nuclear facilities. [Monitoring of animals at DOE facilities to determine exposure pathways]

Description: Biological monitoring programs, as well as relevant radioecological research studies, are reviewed at specific Department of Energy facilities; the program at Oak Ridge National Laboratory is discussed in detail. The biological measurements that are being used for interpreting the impact of a facility on its surrounding environment and nearby population are given. Suggestions which could facilitate interlaboratory comparison studies are presented.
Date: June 5, 1978
Creator: Quintana, L.R.; Oakes, T.W. & Shank, K.E.
Partner: UNT Libraries Government Documents Department

Incidence of human dental fluorosis in the Raft River geothermal area in southern Idaho. Final report

Description: A total of 270 school aged individuals representing 151 families living in the vicinity of the Raft River Geothermal area of Idaho were examined for evidence of dental fluorosis. Of these 132 had some dental anomaly. Fifty-two individuals from 45 families had lesions classified as typical dental fluorosis. Eleven of these, some of which had severe dental fluorosis recently moved into the area from other locations. Samples of the drinking waters that were likely consumed by the individuals with dental fluorosis were collected for analyses. In most instances the fluoride content of the waters were low and would not account for the tooth lesions. Possible reasons for lack of correlation are changing of the composition of the water, other sources of fluoride in the diet, and possibly analytical errors.
Date: September 1, 1978
Creator: Shupe, J.L.; Olson, A.E. & Peterson, H.B.
Partner: UNT Libraries Government Documents Department

Animal Investigation Program 1976 annual report: Nevada test site and vicinity. [Radioanalysis of tissues from animals residing on or near NTS in 1976]

Description: Data are presented from the radioanalysis of tissues collected from cattle and mule deer, desert bighorn sheep, feral horses, and other wildlife that resided on or near the Nevada Test Site during 1976. Other than the naturally occurring potassium-40, gamma-emitting radionuclides were detected infrequently with the exception of /sup 131/I in animal thyroid samples collected after September 25 (the date of a Chinese nuclear test). Strontium-90 concentrations in bones from deer, cattle, and desert bighorn sheep continued the downward trend of recent years. Tritium concentrations were generally within ambient limits with the exception of animals exposed to sources of contamination; e.g., Sedan Crater, drainage ponds from Area 12 tunnels, etc. Analysis of actinide in tissues was emphasized during 1976. Graphs illustrate the /sup 239/P levels in lungs, livers, and femurs from Nevada Test Site beef cattle for the years 1971 through 1976. Femur and lung residue data are nearly identical for each year with liver concentrations being a factor of 2 or 3 lower. Hypothetical dose estimates to man were calculated on the basis of the daily consumption of 0.5 kilogram of liver or muscle from animals that contained peak actinide levels. The highest postulated dose was 11 millirem from tritium from tissues for a mule deer. This dose is about 2% of the 500 millirems/year guide for radiation doses to an individual in the general public. All other postulated doses for consumption of the tissue containing other radionuclides are less than 0.1% of this guide. The food habits of desert bighorn sheep were discussed according to the geographic locations of the animals at time of collection. Grasses made up approximately 60% of the diet at all locations, with shrubs content approaching 30%, and the remainder consisting of various forbs. The movement of 13 mule deer fitted with collars containing ...
Date: November 1, 1978
Creator: Smith, D.D.; Giles, K.R.; Bernhardt, D.E. & Brown, K.W.
Partner: UNT Libraries Government Documents Department

Biocide by-products in aquatic environments. Annual report, October 1, 1977--September 30, 1978. [Analysis and toxicity of by-products from chlorine used in nuclear power plant cooling systems]

Description: The Biocide By-Products in Aquatic Environments Program is composed of analytical chemistry and biological phases with freshwater and marine biological subdivisions. The objectives of the analytical studies are: to identify those chloroorganic chemical compounds that result from the addition of chlorine to fresh or saltwater; to develop methods for detecting chlorinated organics in the effluents discharged to receiving water bodies from nuclear stations; and to verify laboratory findings through analysis for chlorination by-products in water and biota samples from cooling water bodies of nuclear power stations. The objectives of the biological studies are: to investigate the immediate toxicity of specific chlorination by-products (chloroform in freshwater and bromoform in marine waters); to evaluate the chronic toxicity of chlorination by-products; to follow their pathways of action; and to analyze for bioaccumulation or biomagnification of halogenated hydrocarbons on selected aquatic or marine biota.
Date: January 1, 1979
Creator: Anderson, D.R.; Bean, R.M. & Gibson, C.I.
Partner: UNT Libraries Government Documents Department

Dosimetry methods and results for the former residents of Bikini Atoll

Description: The US Government utilized Bikini and Enewetak Atolls in the northern Marshall Islands of Micronesia for atomspheric tests of nuclear explosives in the 1940's and 1950's. The original inhabitants of these atolls were relocated prior to the tests. During the early 1970's, a small but growing population of Marshallese people reinhabited Bikini. Environmental and personnel radiological monitoring programs were begun in 1974 to ensure that doses and dose commitments received by Bikini residents remained within US Federal Radiation Council guidelines. Dramatic increases in /sup 137/Cs body burdens among the inhabitants between April 1977 and 1978 may have played a significant role in the government decision to move the 140 Bikinians in residence off of the atoll in August 1978. The average /sup 137/Cs body burden for the population was 2.3 ..mu..Ci in April 1978. Several individuals, however, exceeded the maximum permissible body burden of 3 ..mu..Ci, and some approached 6 ..mu..Ci. The resultant total dose commitment was less than 200 mrem for the average resident. The average total dose for the mean residence interval of approx. 4.5 years was about 1 rem. The sources of exposure, the probable cause of the unexpected increase in /sup 137/Cs body burdens, and the methods for calculating radionuclide intake and resultant doses are discussed. Suggestions are offered as to the implications of the most significant exposure pathways for the future inhabitation of Bikini and Enewetak. (ERB)
Date: January 1, 1979
Creator: Greenhouse, N.A.
Partner: UNT Libraries Government Documents Department

Imprecision of dose predictions for radionuclides released to the atmosphere: an application of the Monte Carlo-simulation-technique for iodine transported via the pasture-cow-milk pathway

Description: The shortcomings of using mathematical models to determine compliance with regulatory standards are discussed. Methods to determine the reliability of radiation assessment models are presented. Since field testing studies are impractical, a deficiency method, which analyzes the variability of input parameters and the impact of their variability on the predicted dose, is used. The Monte Carlo technique is one of these methods. This technique is based on statistical properties of the model output when input parameters inserted in the model are selected at random from a prescribed distribution. The one big assumption one must make is that the model is a correct formulation of reality. The Gaussian plume model for atmospheric transport of airborne effluents was used to study the pasture-cow-milk-man exposure pathway and the dose calculated from radioiodine (/sup 131/I) transported over this pathway. (DMC)
Date: January 1, 1979
Creator: Schwarz, G. & Hoffman, F.O.
Partner: UNT Libraries Government Documents Department

Parameter uncertainty and model predictions: a review of Monte Carlo results

Description: Studies of parameter variability by Monte Carlo analysis are reviewed using repeated simulations of the model with randomly selected parameter values. At the beginning of each simulation, parameter values are chosen from specific frequency distributions. This process is continued for a number of iterations sufficient to converge on an estimate of the frequency distribution of the output variables. The purpose was to explore the general properties of error propagaton in models. Testing the implicit assumptions of analytical methods and pointing out counter-intuitive results produced by the Monte Carlo approach are additional points covered.
Date: January 1, 1979
Creator: Gardner, R.H. & O'Neill, R.V.
Partner: UNT Libraries Government Documents Department

Radiological aspects of sea bed dumping in the deep oceans

Description: In order to control coastal discharges or ocean dumping of any kind of material, it is necessary to determine a release rate. This can only come from a knowledge of the composition and chemical form of the source materials, the distribution and bioavailability of these materials in the ocean ecosystem, the degree and rates of bioaccumulation and the actual or potential use of the ocean resources. With this information release rates within acceptable limits for man and the ecosystem can then be determined. Today, probably the only situations which apply this approach are the controlled disposal of radioactive wastes. In this paper a recent radiological assessment of the dumping of packaged radioactive wastes on the seabed is discussed and some environmental aspects of the United States Department of Energy program are described examining the feasibility of the emplacement of contained radioactive wastes within the deep ocean sediments.
Date: January 1, 1979
Creator: Templeton, W.L.
Partner: UNT Libraries Government Documents Department

Radiological impact of uranium tailings and alternatives for their management

Description: Uncontrolled tailings piles are mobile sources of fugitive dust that may produce a practically uncleanable adjacent environment. A practical procedure for managing solid tailings is addition of surface moisture, mechanical and gravitational separation of slimes, and storage of slimes below solution tailings. Presently practical alternatives for tailings management are variations of two basic methods - surface below-ground disposal. Isolation of tailings by natural materials such as clay lenses and combinations of overburden, top soil, vegetation and rip-rap may provide both minimization of exposure and stability. Experimental measurement of radon flux over two inactive tailings, acid and carbonate leached tailings resulted in average specific flux values of phi infinity approx. = 0.64 and phi infinity approx. = 0.30 (pCi Rn-222/m/sup 2/ sec) / (pCi Ra-226/g), respectively. The average diffusion coefficient for these tailings were, respectively, 2.4 x 10/sup -3/ and 5.7 x 10/sup -4/ cm/sup 2//sec. Tailings covered with native soil of clay-silt-sand mixture to a depth of 225 cm resulted in attenuation of flux with diffusion coefficients of 3.69 x 10/sup -3/ and 3.60 x 10/sup -3/ cm/sup 2//sec for ACID and ALKO sites, respectively. By means of the UDAD code dose commitments were estimated for inhalation of particulates and radon and for external exposure under three degrees of surface moisture on the tailings. Based on these analyses and assumption that the dose contribution from ingestion pathway is comparable in magnitude to that of inhalation, both compliance with the 25 mrem/year limit and reduction of flux to background level is feasible. Stability of alternative decommissioned tailings over the predictable future is discussed.
Date: January 1, 1979
Creator: Momeni, M.H.; Kisieleski, W.E.; Tyler, S.; Zielen, A.; Yuan, Y. & Roberts, C.J.
Partner: UNT Libraries Government Documents Department

Stack released plutonium in the environment of a nuclear fuel reprocessing facility. [Savannah River Plant]

Description: Chemical separations facilities at the Savannah River Plant have released very small quantities of plutonium to the environment since 1955. Characterization studies of airborne particulates from the process stack show that the plutonium is nearly always attached to nonradioactive particles. The geometric mean diameter of plutonium-bearing particulates in the stack gas is 5.43 ..mu..m. Most of the particles contain less than 10/sup -15/ Ci of /sup 239/Pu. Studies with cascade impactors 1.1 m above the ground indicated that the average annual air concentration was 612 x 10/sup -18/ Ci/m/sup 3/ (less than 0.1% of the maximum permissible concentration recommended by the ICRP). Cropping studies showed plutonium concentrations of 3 x 10/sup -3/ pCi/g in wheat, 5.5 x 10/sup -4/ in soybeans, and 1.7 x 10/sup -4/ in corn. The 70-year dose-to-bone from ingesting 10/sup 5/ g of grain would be less than 1 mrem.
Date: January 1, 1979
Creator: Horton, J.H.; Sanders, S.M. & Corey, J.C.
Partner: UNT Libraries Government Documents Department

Systematic approach for assessment of alternative nuclear waste management strategies

Description: A systematic approach for alternative nuclear waste management assessment is prescribed for evaluating the fate and transport of radwaste in the environment and to man. The approach consists of a system of flow dynamic and waste transport models for the physical environment, transfer models to biota, and dose models to man. Flow dynamic and waste transport models are included for computing spatial-temporal variations of the flow field and radwaste concentration in subsurface aquifers, surface water regimes, estuaries/oceans, and the atmosphere. Transfer models are linked to flow dynamic and waste transport models to study the uptake from and to the physical environment of the waste by aquatic and terrestrial biota. Dose models are used to compute both the radwaste input to man and its effects on man. With these series of computations, the radiation dose from alternative nuclear waste management strategies can be computed. Coupled with the exposure and effect analysis, the approach should facilitate the selection of the best management methodologies among many alternatives.
Date: January 1, 1979
Creator: Yeh, G.T.
Partner: UNT Libraries Government Documents Department

Limits for the burial of the Department of Energy transuranic wastes

Description: Potential limits for the shallow earth burial of transuranic elements were examined by simplified models of the individual pathways to man. Pathways examined included transport to surface steams, transport to ground water, intrusion, and people living on the burial ground area after the wastes have surfaced. Limits are derived for each pathway and operational limits are suggested based upon a dose to the organ receiving the maximum dose rate of 0.5 rem/y after 70 years of exposure for the maximum exposed individual.
Date: January 15, 1979
Creator: Healy, J.W. & Rodgers, J.C.
Partner: UNT Libraries Government Documents Department

AQUAMAN: a computer code for calculating dose commitment to man from aqueous releases of radionuclides. [Internal and external dose conversion factors and bioaccumulation factors for 56 radionuclides]

Description: AQUAMAN is an interactive computer code for calculating values of dose (50-year dose commitment) to man from aqueous releases of radionuclides from nuclear facilities. The data base contains values of internal and external dose conversion factors, and bioaccumulation (freshwater and marine) factors for 56 radionuclides. A maximum of 20 radionuclides may be selected for any one calculation. Dose and cumulative exposure index (CUEX) values are calculated for total body, GI tract, bone, thyroid, lungs, liver, kidneys, testes, and ovaries for each of three exposure pathways: water ingestion, fish ingestion, and submersion. The user is provided the option at the time of execution to change the default values of most of the variables, with the exception of the dose conversion factor values. AQUAMAN is written in FORTRAN for the PDP-10 computer.
Date: February 1, 1979
Creator: Shaeffer, D. L. & Etnier, E. L.
Partner: UNT Libraries Government Documents Department

Radiological safety evaluation report for NUWAX-79 exercise. [Simulation of nuclear weapons accident]

Description: An analysis of the radiological safety of the NUWAX-79 exercise to be conducted on the Nevada Test Site in April 1979 is given. An evaluation of the radiological safety to the participants is made using depleted uranium (D-38) in mock weapons parts, and /sup 223/Ra and its daughters as a radioactive contaminant of equipment and terrain. The radiological impact to offsite persons is also discussed, particularly for people living at Lathrop Wells, Nevada, which is located 7 miles south of the site proposed for the exercise. It is the conclusion of this evaluation that the potential radiological risk of this exercise is very low, and that no individual should receive exposure to radioactivity greater than one-tenth of the level permitted under current federal radiation exposure guidelines.
Date: March 1, 1979
Creator: King, W.C.
Partner: UNT Libraries Government Documents Department

Transfer coefficients for terrestrial foodchain: their derivation and limitations

Description: Transfer coefficients to predict the passage of isotopes from the environment to terrestrial foods have been derived for various radionuclides of importance in the nuclear fuel cycle. These data update and extend previously recommended handbook values. We derive transfer coefficients to terrestrial foods and describe the systematics of the derived transfer coefficients. Suggestions are offered for changes in the values of transfer coefficients to terrestrial foods that now appear in federal regulatory guides. Deficiencies in our present knowledge concerning transfer coefficients and limitations in the use of these values to ensure compliance with radiation protection standards are discussed.
Date: March 30, 1979
Creator: Ng, Y.C.; Colsher, C.S. & Thompson, S.E.
Partner: UNT Libraries Government Documents Department

Annual environmental monitoring report, January--December 1978. [Stanford Linear Accelerator Center]

Description: Environmental monitoring results continue to demonstrate that, except for penetrating radiation, environmental radiological impact due to SLAC operation is not distinguishable from natural environmental sources. During 1978, the maximum neutron dose near the site boundary was 6.6 mrem. This represents about 6.6% of the annual dose from natural sources at this elevation, and 1.3% of the technical standard of 500 mrem per person annually. There have been no measurable increases in radioactivity in ground water attributable to SLAC operations since 1966. Because of major new construction, well water samples were not collected and analyzed during 1978. Construction activities have also temporarily placed our sampling stations for the sanitary and storm sewers out of service. They will be re-established as soon as construction activities permit. Airborne radioactivity released from SLAC continues to make only a negligible environmental impact, and results in a site boundary annual dose of less than 0.01 mrem; this represents less than 0.01% of the annual dose from the natural radiation environment, and about 0.002% of the technical standard.
Date: April 1, 1979
Partner: UNT Libraries Government Documents Department