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Fine and coarse components in surface sediments from Bikini Lagoon

Description: In 1979, 21 years after the moratorium on nuclear testing in the Marshall Islands, surface sediment samples (to depths of 2 and 4 cm) were collected from 87 locations in the lagoon of Bikini Atoll, one of the two sites in the Marshall Islands used by the United States to test nuclear devices from 1946 through 1958. The main purpose for the collections was to map the distribution of long-lived man-made radionuclides associated with the bottom material. In addition the samples were processed to estimate the fraction of fine and coarse components to show, by comparison, what modifications occurred in the composition since the sediments were first described in samples collected before testing in 1946. Nuclear testing produced more finely divided material that is now found in the surface sediment layer over large areas of the lagoon and especially in regions of the lagoon and reef adjacent to test sites. The 5 cratering events alone at Bikini Atoll redistributed sufficient material to account for the higher inventory of fine material found over the surface 4 cm of the sediment of the lagoon. Although the fraction of fine material in the bottom sediments was altered by the nuclear events, the combined processes of formation, transport and deposition were not sufficiently dynamic to greatly change the general geographical features of the major sedimentary components over most of the lagoon floor.
Date: January 1, 1997
Creator: Noshkin, V. E.
Partner: UNT Libraries Government Documents Department

Plutonium mobilization from sedimentary sources to solution in the marine environment

Description: Inventories of plutonium radionuclides greatly in excess of global fallout levels persists in the benthic environments of Bikini and Eniwetok Atolls. It now appears that the atolls have reached a chemical steadystate condition with respect to the partitioning of /sup 239 +240/Pu between solution and solid phases of the environment. The mobilized /sup 239 +240/Pu has solute-like characteristics, passes rapidly and readily through dialysis membranes, has adsorption characteristics similar to those of fallout plutonium in the open ocean, and exists in solution primarily as some oxidized +5 or +6 chemical species. Water-column profiles of /sup 239 +240/Pu taken outside the atolls show a plutonium excess in the deep water mass. This remobilized /sup 239 +240/Pu possibly originates from the contaminated sediments previously deposited on the outer slopes of the atolls and surrounding basins.
Date: October 1, 1979
Creator: Noshkin, V.E. & Wong, K.M.
Partner: UNT Libraries Government Documents Department

Plutonium in the north equatorial Pacific

Description: The concentrations of plutonium in samples collected from the north equatorial region of the Pacific Ocean are presented. The results discussed in this abstract are preliminary, and some of the conclusions and descriptions of results may be revised after results from similar tests made by Woods Hole Oceanographic Institute are critically compared. An early exchange of these data is warranted because the results are directly related to the objectives of the workshop--to assess the processes, behavior, and fate of radionuclides in oceanic environments.
Date: May 15, 1979
Creator: Noshkin, V.E. & Wong, K.M.
Partner: UNT Libraries Government Documents Department

Radionuclides in sediments from the northeast Atlantic disposal site

Description: The concentrations and inventories of /sup 239 +240/Pu in sediments from within the boundaries of the low-level radioactive waste-disposal site in the northeast Atlantic are not significantly different from global fallout levels expected in deep-sea sediments from this region of the Atlantic. No man-made gamma-emitting radionuclides were above detection limits in the sediment samples analyzed. Further, there is no indication that past disposal practices have led to an area-wide contamination of the site with waste-related radionuclides. 3 references, 2 figures.
Date: November 1, 1983
Creator: Noshkin, V.E.; Wong, K.M. & Eagle, R.J.
Partner: UNT Libraries Government Documents Department

Problems associated with transuranium determination of suspended solids in seawater samples

Description: Particulate material collected by filtration from the north Equatorial Pacific Ocean has been analyzed for plutonium and other radionuclides. Different filter pore size, types of filter substrates, flow rates, and sample volumes were evaluated. Retention of /sup 239 +240/Pu was found to vary with the sample volume filtered and was not greatly affected by the type of filter substrate, flow rate, or porosity tested. About 7 +- 3% of the /sup 239 +240/Pu activity in north Equatorial Pacific surface water is found with the particulate material filtered from 120 liters of water, while less than 1% is retained on samples with volume of 20,000-70,000 liters. Clearly an understanding of these results is necessary to correctly assess the quantity of plutonium, other radionuclides and trace elements associated with and transported by particulate material in the marine environment.
Date: October 4, 1979
Creator: Wong, K.M.; Jokela, T.A. & Noshkin, V.E.
Partner: UNT Libraries Government Documents Department

Sediment studies at Bikini Atoll part 3. Inventories of some long-lived gamma-emitting radionuclides associated with lagoon surface sediments

Description: Surface sediment samples were collected during 1979 from 87 locations in the lagoon at Bikini Atoll. The collections were made to better define the concentrations and distribution of long-lived radionuclides associated with the bottom material and to show what modifications occurred to the composition of the surface sediment from the nuclear testing program conducted by the United States at the Atoll between 1946 and 1958. This is the last of three reports on Bikini sediment studies. In this report, we discuss the concentrations and inventories of the residual long-lived gamma-emitting radionuclides in sediments from the lagoon. The gamma-emitting radionuclides detected most frequently in sediments collected in 1979, in addition to Americium-241 ({sup 241}Am) (discussed in the second report of this series), included Cesium-137 ({sup 137}Cs), Bismuth-207 ({sup 207}Bi), Europium-155 ({sup 155}Eu), and Cobalt-60 ({sup 60}Co). Other man-made, gamma-emitting radionuclides such as Europium-152,154 ({sup 152,154}Eu), Antimony-125 ({sup 125}Sb), and Rhodium-101,102m ({sup 101,102m}Rh) were occasionally measured above detection limits in sediments near test site locations. The mean inventories for {sup 137}Cs, {sup 207}Ei, {sup 155}Eu, and {sup 60}Co in the surface 4 cm of the lagoon sediment to be 1.7, 0.56, 7.76, and 0.74 TBq, respectively. By June 1997, radioactive decay would reduce these values to 1.1, 0.38, 0.62, and 0.07 TBq, respectively. Some additional loss results from a combination of different processes that continuously mobilize and return some amount of the radionuclides to the water column. The water and dissolved constituents are removed from the lagoon through channels and exchange with the surface waters of the north equatorial Pacific Ocean. Highest levels of these radionuclides are found in surface deposits lagoonward of the Bravo Crater. Lowest concentrations and inventories are associated with sediment lagoonward of the eastern reef. The quantities in the 0-4 cm surface layer are estimated to be less ...
Date: December 1, 1997
Creator: Noshkin, V.E.
Partner: UNT Libraries Government Documents Department

References to Studies of 137Cs, 90Sr and 239+240Pu in the Pacific Ocean a Bibliography

Description: This report contains a listing of publications known to this author on reported concentrations, reviews and discussions of {sup 137}Cs, {sup 90}Sr and {sup 239+240}Pu in seawater, sediment and the biota from parts of the North and South Pacific Ocean. Each reference has been assigned an accession number consisting of the first three letters of the first author's last name followed by the first letter of the first name, the year of the publication and an assigned number. Studies in both the coastal areas and the open ocean are included as well as those providing data within lagoons of coral atolls. Some references to the radionuclides in the Indian Ocean are also provided.
Date: February 1, 2001
Creator: Noshkin, V.E.
Partner: UNT Libraries Government Documents Department

Radionuclide characterization and associated dose from long-lived radionuclides in close-in fallout delivered to the marine environment at Bikini and Enewetak Atoll

Description: Between June 1946 and October 1958, Enewetak and Bikini Atolls were used by the United States as testing grounds for 66 nuclear devices. The combined explosive yield from these tests was 107 Mt (Mt TNT equivalents). This testing produced close-in fallout debris that was contaminated with quantities of radioactive fission and particle activated products, and unspent radioactive nuclear fuel that entered the aquatic environment of the atolls. Today, the sediments in the lagoons are reservoirs for 10's of TBq of the transuranics and some long-lived fission and activation products. The larger amounts of contamination are associated with fine and coarse sediment material adjacent to the locations of the high yield explosions. Radionuclides are also distributed vertically in the sediment column to various depths in all regions of the lagoons. Concentrations greater than fallout background levels are found in filtered water sampled over several decades from all locations and depths in the lagoons. This is a direct indication that the radionuclides are continuously mobilized to solution from the solid phases. Of particular importance is the fact that the long-lived radionuclides are accumulated to different levels by indigenous aquatic plants and organisms that are used as food by resident people. One might anticipate finding continuous high contamination levels in many of the edible marine organisms from the lagoons, since the radionuclides associated with the sediments are not contained and are available to the different organisms in a relatively shallow water environment. This is not the case. We estimate that the radiological dose from consumption of the edible parts of marine foods at Enewetak and Bikini is presently about 0.05% of the total 50-year integral effective dose from all other exposure pathways that include ingestion of terrestrial foods and drinking water, external exposure and inhalation. The total radiological dose from the marine pathway ...
Date: September 1, 1998
Creator: Noshkin, V. E. & Robison, W. L.
Partner: UNT Libraries Government Documents Department

Sediment studies at Bikini Atoll part 1. distribution of fine and coarse components in surface sediments

Description: In 1979, 21 years after the moratorium on nuclear testing in the Marshall Islands, surface sediment samples (to depths of 2 and 4 cm) were collected from 87 locations over the floor of Bikini lagoon. The main purpose for the collections was to map the distribution of long- lived man-made radionuclides associated with the bottom material. In addition the samples were processed to estimate the fraction of fine and coarse components to show what modifications occurred since the sediment composition was first described in samples collected before testing in 1946. In this report a comparison is made of the amount and distribution of fine material associated with the lagoon surface sediment before and after the testing of nuclear devices. Nuclear testing produced more finely divided material in-the surface sediment layer over large areas of the lagoon and especially in regions of the lagoon and reef adjacent to test sites. Five cratering events at Bikini Atoll generated sufficient material to account for the inventory of new fine material found over the bottom surface of the lagoon. Although the fraction of fine material in the bottom sediments was altered by the nuclear events, the combined processes of formation, transport and deposition were not sufficiently dynamic to alter the geographical features of the major sedimentary components over most of the lagoon floor.
Date: January 1, 1997
Creator: Noshkin, V. E.; Eagle, R.J. & Robison, W.L.
Partner: UNT Libraries Government Documents Department

Transuranic concentrations in reef and pelagic fish from the Marshall Islands. [/sup 239/Pu, /sup 240/Pu]

Description: Concentrations of /sup 239 + 240/Pu are reported in tissues of several species of reef and pelagic fish caught at 14 different atolls in the northern Marshall Islands. Several regularities that are species dependent are evident in the distribution of /sup 239 + 240/Pu among different body tissues. Concentrations in liver always exceeded those in bone and concentrations were lowest in the muscle of all fish analyzed. A progressive discrimination against /sup 239 + 240/Pu was observed at successive trophic levels at all atolls except Bikini and Enewetak, where it was difficult to conclude if any real difference exists between the average concentration factor for /sup 239 + 240/Pu among all fish, which include bottom feeding and grazing herbivores, bottom feeding carnivores, and pelagic carnivores from different atoll locations. The average concentration of /sup 239 + 240/Pu in the muscle of surgeonfish from Bikini and Enewetak was not significantly different from the average concentrations determined in these fish at the other, lesser contaminated atolls. Concentrations among all 3rd, 4th, and 5th trophic level species are highest at Bikini where higher environmental concentrations are found. The reasons for the anomalously low concentrations in herbivores from Bikini and Enewetak are not known.
Date: September 1, 1980
Creator: Noshkin, V.E.; Eagle, R.J.; Wong, K.M. & Jokela, T.A.
Partner: UNT Libraries Government Documents Department

Biogeochemical studies of long-lived radionuclides in marine environments

Description: Research results from several studies relevant to seabed dispoal of radioactive wastes are briefly discussed. The studies include: (1) mobilization of plutonium from Enewetak and Bikini lagoon sediments to seawater; (2) concentrations of /sup 90/Sr, /sup 137/Cs, /sup 239+240/Pu, /sup 241/Am, /sup 207/Bi and /sup 210/Pb-/sup 210/Bi-/sup 210/Po in fish from the Marshall Islands; and (3) plutonium in northeast Atlantic sediments. (ACR)
Date: January 1, 1985
Creator: Noshkin, V.E.; Wong, K.M.; Eagle, R.J. & Jokela, T.A.
Partner: UNT Libraries Government Documents Department

Environmental radiological studies downstream from the Rancho Seco Nuclear Power Generating Station, 1985

Description: Information compiled in 1985 while assessing the environmental impact of radionuclides previously discharged with aqueous releases from the Rancho Seco Nuclear Power Generating Plant is presented. In October 1984, the quantities of gamma-emitting radionuclides in water discharged to Clay Creek from the plant were reduced below operationally defined detection limits for liquid effluents. However, radionuclides previously discharged persist in the downstream environment and are found in many aquatic dietary components. /sup 134/Cs and /sup 137/Cs are the primary gamma-emitting radionuclides detected in the edible flesh of different fish, crayfish, and frogs. Coefficients for exponential equations are generated, from a least square analysis, that relate the change in concentration of /sup 137/Cs in fish to distance downstream and time between March and October 1985. Concentrations of /sup 137/Cs in surface creek sediments also decreased in the downstream direction much in the same manner as concentrations decreased in fish. However, there was no significant difference in the radiocesium concentrations in surface sediements collected from comparable locations during both 1984 and 1985.
Date: February 6, 1986
Creator: Noshkin, V.E.; Wong, K.M.; Eagle, R.J.; Brunk, J.L. & Jokela, T.A.
Partner: UNT Libraries Government Documents Department

Environmental radiological studies downstream from the Rancho Seco Nuclear Power Generating Station - 1985. Appendices. Part II

Description: Eight appendices address the following concentrations of radionuclides: in fish; in frog legs; in crayfish; in sediments; in soil samples; in surface and ground water samples; in water hyacinths; and in beef samples.
Date: January 23, 1986
Creator: Noshkin, V.E.; Wong, K.M.; Eagle, R.J.; Brunk, J.L. & Jokela, T.A.
Partner: UNT Libraries Government Documents Department

Concentration of radionuclides in fresh water fish downstream of Rancho Seco Nuclear Generating Plant

Description: Fish were collected for radionuclide analysis over a 5-month period in 1984 from creeks downstream of the Rancho Seco Nuclear Generating Plant, which has been discharging quantities of some fission and activation products to the waterway since 1981. Among the fish, the bluegill was selected for intensive study because it is very territorial and the radionuclide concentrations detected should be representative of the levels in the local environment at the downstream locations sampled. Among the gamma-emitting radionuclides routinely released, only /sup 134/Cs and /sup 137/Cs were detected in the edible flesh of fish. Concentrations in the flesh of fish decreased with distance from the plant. The relationship between concentration and distance was determined to be exponential. Exponential equations were generated to estimate concentrations in fish at downstream locations where no site-specific information was available. Mean concentrations of /sup 137/Cs in bluegill collected during April, May, July and August from specific downstream stations were not significantly different in spite of the release of 131 mCi to the creeks between April and August. The concentrations in fish are not responding to changes in water concentrations brought about by plant discharges. Diet appears to be a more significant factor than size or weight or water concentration in regulating body burdens of /sup 137/Cs in these fish.
Date: December 27, 1984
Creator: Noshkin, V.E.; Eagle, R.J.; Dawson, J.M.; Brunk, J.L. & Wong, X.M.
Partner: UNT Libraries Government Documents Department

Detection of cadmium radioactivity in the marine environment

Description: Sediment and tissues from different marine organisms recently collected atolls of the Marshall Islands have been found to contain measurable amounts of /sup 113m/Cd previously deposited to the atolls during the testing of nuclear devices at the Pacific Proving Grounds. /sup 113m/Cd has been also detected in some internal organs of mullet collected from the east coast of the United States in an area contaminated only with global fallout debris. This is one of the few summaries to show that this long-lived radionuclide (T/sub 1/2/ = 14.6 yr) exists and persists in the marine environment. It is the dominant anthropogenic radionuclide in the liver of some pelagic fish from Bikini and Enewetak Atolls and is found concentrated in other tissues and organs of all fish analyzed. Dose to man from /sup 113m/Cd ingestion is being assessed at the Marshall Islands and should be done at any other global site where contamination by this radionuclide is suspected in the aquatic environment.
Date: December 1, 1980
Creator: Noshkin, V.E.; Wong, K.M.; Eagle, R.J. & Anglin, D.L.
Partner: UNT Libraries Government Documents Department

Environmental radiological studies conducted during 1986 in the vicinity of the Rancho Seco Nuclear Power Generating Station

Description: This report summarizes the information compiled in 1986 for our assessment of the environmental impact of radionuclides discharged with aqueous releases from the Rancho Seco Nuclear Power Generating Plant. In October 1984, a liquid-effluent control program was initiated that significantly reduced the quantities of radionuclides discharged with liquid waste from the plant. However, results from our sampling program in 1986 indicate that previously discharged radionuclides persist in the downstream environment and are found in many aquatic dietary components although at concentrations much lower than those measured in 1984 and 1985. The greatly reduced activities in the dietary components from the aquatic environment attest to the effectiveness of the liquid-effluent control program. Concentrations in the flesh of fish from the creeks have decreased over time and with distance from the plant outfall. The mean concentration of /sup 137/Cs in fish collected from Laguna Creek at locations more than 7.5 km from Rancho Seco is now comparable to the concentration determined in fresh-water fish randomly selected from Chicago, Illinois, markets. By August 1986, the mean concentration of /sup 137/Cs in the flesh of bluegill had fallen to 7% of the concentration measured in fish from comparable locations in 1984 and was 30% of the mean concentration measured in these fish during August 1985. Stable potassium in the water plays a major role in the accumulation of /sup 137/Cs by fish. Concentrations of /sup 137/Cs in the surface sections of creek sediments also declined between the end of 1984 and 1986 with an effective half-life of approximately 2 y. Surface soils collected around a perimeter 11 km from Rancho Seco and from ranchlands closer to the plant showed only concentrations of /sup 137/Cs originating from global fallout. Soils previously irrigated with Clay Creek water retain levels of both /sup 134/Cs and /sup 137/Cs.
Date: March 1, 1987
Creator: Noshkin, V.E.; Wong, K.M.; Eagle, R.J.; Brunk, J.L. & Jokela, T.A.
Partner: UNT Libraries Government Documents Department

Concentrations of radionuclides in fish collected from Bikini Atoll between 1977 and 1984

Description: This report summarizes all available data on the concentrations of radionuclides in fish from Bikini Atoll between 1977 and 1984. As found in other global studies, /sup 137/Cs is most highly accumulated in edible flesh of all species of fish, the lowest fractions are found in the bone or liver. The mean concentration of /sup 137/Cs in muscle of reef fish from the southern part of the atoll is comparable to the global fallout concentration measured in market samples of fish collected from Chicago, Illinois, in 1982. /sup 90/Sr is generally associated with non-edible parts of fish, such as bone or viscera. Twenty-five to fifty percent of the total body burden of /sup 60/Co is accumulated in the muscle tissue; the remainder is distributed among the liver, skin, and viscera. The mean concentration of /sup 60/Co in fish has been decreasing at a rate faster than radiological decay alone. Most striking is the range of /sup 207/Bi concentrations among different species of fish collected at the same time and place. Highest concentrations of /sup 207/Bi were consistently detected in the muscle (and other tissues) of goatfish and some of the pelagic lagoon fish. In other reef fish, such as mullet, surgeonfish, and parrotfish, /sup 207/Bi was usually below detection limits by gamma spectrometry. Over 70% of the whole-body activity of /sup 207/Bi in goatfish is associated with the muscle tissue, whereas less than 5% is found in the muscle of mullet and surgeonfish. Neither /sup 239 +240/Pu nor /sup 241/Am is significantly accumulated in the muscle tissue of any species of fish. Apparently, /sup 238/Pu is in a more readily available form for accumulation by fishes than /sup 239 +240/Pu. Based on a daily ingestion rate of 200 q of fish flesh, dose rates to individuals through the fish-food ingestion ...
Date: July 1, 1986
Creator: Noshkin, V.E.; Wong, K.M.; Eagle, R.J.; Jokela, T.A. & Brunk, J.A.
Partner: UNT Libraries Government Documents Department

Comparative behavior of plutonium and americium in the equatorial Pacific

Description: Inventories of /sup 239 +240/Pu and /sup 241/Am greatly in excess of global fallout levels persist in the benthic environments of Bikini and Enewetak Atolls. The amount of /sup 239 +240/Pu mobilized to solution at the atolls can be predicted from a distribution coefficient K/sub d/ of 2.3 x 10/sup 5/ and the mean sediment concentrations. The mobilized /sup 239 +240/Pu has solute-like characteristics and different valence states coexist in solution - the largest fraction of the soluble plutonium is in an oxidized form (+V,VI). The adsorption of plutonium to sediments is not completely reversible because of changes that occur in the relative amounts of the mixed oxidation states in solution with time. Characteristics of /sup 239 +240/Pu described at one location may not necessarily describe its behavior elsewhere. The relative amounts of /sup 241/Am to /sup 239 +240/Pu may be altered in future years because of mobilization and radiological decay.
Date: January 1, 1983
Creator: Noshkin, V.E.; Wong, K.M.; Jokela, T.A.; Brunk, J.L. & Eagle, R.J.
Partner: UNT Libraries Government Documents Department

Radiochemical procedures for analysis of Pu, Am, Cs and Sr in water, soil, sediments and biota samples

Description: The Environmental Radioactivity Analysis Laboratory (ERAL) was established as an analytical facility. The primary function of ERAL is to provide fast and accurate radiological data of environmental samples. Over the years, many radiochemical procedures have been developed by the staffs of ERAL. As result, we have found that our procedures exist in many different formats and in many different notebooks, documents and files. Therefore, in order to provide for more complete and orderly documentation of the radiochemical procedures that are being used by ERAL, we have decided to standardize the format and compile them into a series of reports. This first report covers procedures we have developed and are using for the radiochemical analysis of Pu, Am, Cs, and Sr in various matrices. Additional analytical procedures and/or revisions for other elements will be reported as they become available through continuation of these compilation efforts.
Date: February 1, 1994
Creator: Wong, K. M.; Jokela, T. A. & Noshkin, V. E.
Partner: UNT Libraries Government Documents Department

Transuranic radionuclides dispersed into the aquatic environment, a bibliography

Description: The purpose of this project was to compile a bibliography of references containing environmental transuranic radionuclide data. Our intent was to identify those parameters affecting transuranic radionuclide transport that may be generic and those that may be dependent on chemical form and/or environmental conditions (i.e., site specific) in terrestrial, aquatic and atmospheric environments An understanding of the unique characteristics and similarities between source terms and environmental conditions relative to transuranic radionuclide transport and cycling will provide the ability to assess and predict the long term impact on man and the environment. An additional goal of our literature review, was to extract the ranges of environmental transuranic radionuclide data from the identified references for inclusion in a data base. Related to source term, these ranges of data can be used to calculate the dose to man from the radionuclides, and to perform uncertainty analyses on these dose assessments. On the basis of our reviews, we have arbitrarily outlined five general source terms. These are fallout, fuel cycle waste, accidents, disposal sites and resuspension. Resuspension of the transuranic radionuclides is a unique source term, in that the radionuclides can originate from any of the other source terms. If these transuranic radionuclides become resuspended into the air, they then become important as a source of inhaled radionuclides.
Date: April 1, 1994
Creator: Noshkin, V. E.; Stoker, A. C. & Wong, Kai M.
Partner: UNT Libraries Government Documents Department

Transuranic radionuclides from resuspension in the environment, a bibliography

Description: The purpose of this project was to compile a bibliography of references containing environmental transuranic radionuclide data. Our intent was to identify those parameters affecting transuranic radionuclide transport that may be generic and those that may be dependent on chemical form and/or environmental conditions. An understanding of the unique characteristics and similarities between source terms and environmental conditions relative to transuranic radionuclide transport and cycling will provide the ability to assess and predict the long term impact on man and the environment. An additional goal of our literature review, was to extract the ranges of environmental transuranic radionuclide data from the identified references for inclusion in a data base. Related to source term, these ranges of data can be used to calculate the dose to man from the radionuclides, and to perform uncertainty analyses on these dose assessments. On the basis of our reviews, we have arbitrarily outlined five general source terms. These are fallout, fuel cycle waste, accidents, disposal sites and resuspension. Resuspension of the transuranic radionuclides is an unique source term, in that the radionuclides can originate from any of the other source terms. If these transuranic radionuclides become resuspended into the air, they then become important as a source of inhaled radionuclides. This bibliography is a compilation of the references containing studies of plutonium and americium in the environment as a result of resuspension.
Date: April 1, 1994
Creator: Stoker, A. C.; Shinn, J. H. & Noshkin, V. E.
Partner: UNT Libraries Government Documents Department