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Ac$sup 227$ AND Th$sup 228$ PRODUCTION AS A FUNCTION OF TIME FOR VARIOUS VALUES OF NEUTRON FLUX. (Information Report)

Description: The amount of Ac/sup 227/ per curie of Ra/sup 226/ was calculated for various values of neutron flux and various Irradiation times. The amount of Th/ sup 228/ produced per curie of Ra/sup 226/ and the percentage of Ac/sup 227/ converted to Th/sup 228/ relative to the total amount of Ac/sup 227/ produced were also calculated. (W.D.M.)
Date: August 28, 1952
Creator: Grove, G. R.; Russell, L. N. & Orr, S. R.
Partner: UNT Libraries Government Documents Department

Research in Radiobiology. Annual Report of Work in Progress on the Chronic Toxicity Program

Description: Separate abstracts were prepared on 8 sections of this report. Data are also included on the status of dogs at various time intervals following the injection of various doses of Ra/sup 226/, Pu/sup 239/, Ra/sup 228/, Th/sup 228, and Sr/sup 90/. (C. H.)
Date: March 31, 1962
Creator: Dougherty, T. F.
Partner: UNT Libraries Government Documents Department

Long-term surveillance plan for the Canonsburg, Pennsylvania, disposal site

Description: This document establishes elements of the US Department of Energy`s (DOE) Long-Term Surveillance Plan for the Canonsburg, Pennsylvania, disposal site. The US Nuclear Regulatory Commission (NRC) will use this plan in support of license issuance for the long-term surveillance of the Canonsburg site. The Canonsburg (CAN) site is located within the borough of Canonsburg, Washington County, in southwestern Pennsylvania. The Canonsburg site covers approximately 30 acres (74 hectares). The disposal cell contains approximately 226,000 tons (241,000 tons) of residual radioactive material (RRM). Area C is southeast of the Canonsburg site, between Strabane Avenue and Chartiers Creek. Contaminated soils were removed from Area C during the remedial action, and the area was restored with uncontaminated fill material.After this cleanup, residual quantities of thorium-230 were detected at several Area C locations. The remedial action plan did not consider the ingrowth of radium-226 from thorium-230 as part of the Area C cleanup, and only two locations contained sufficient thorium-230 concentrations to result in radium-226 concentrations slightly above the US Environmental Protection Agency (EPA) standards.
Date: October 1, 1995
Partner: UNT Libraries Government Documents Department

Rapid Method for Ra-226 and Ra-228 in Water Samples

Description: The measurement of radium isotopes in natural waters is important for oceanographic studies and for public health reasons. Ra-226 (1620 year half-life) is one of the most toxic of the long-lived alpha emitters present in the environment due to its long life and its tendency to concentrate in bones, which increases the internal radiation dose of individuals. The analysis of radium-226 and radium-228 in natural waters can be tedious and time-consuming. Different sample preparation methods are often required to prepare Ra-226 and Ra-228 for separate analyses. A rapid method has been developed at the Savannah River Environmental Laboratory that effectively separates both Ra-226 and Ra-228 (via Ac-228) for assay. This method uses MnO{sub 2} Resin from Eichrom Technologies (Darien, IL, USA) to preconcentrate Ra-226 and Ra-228 rapidly from water samples, along with Ba-133 tracer. DGA Resin{reg_sign} (Eichrom) and Ln-Resin{reg_sign} (Eichrom) are employed in tandem to prepare Ra-226 for assay by alpha spectrometry and to determine Ra-228 via the measurement of Ac-228 by gas proportional counting. After preconcentration, the manganese dioxide is dissolved from the resin and passed through stacked Ln-Resin-DGA Resin cartridges that remove uranium and thorium interferences and retain Ac-228 on DGA Resin. The eluate that passed through this column is evaporated, redissolved in a lower acidity and passed through Ln-Resin again to further remove interferences before performing a barium sulfate microprecipitation. The Ac-228 is stripped from the resin, collected using cerium fluoride microprecipitation and counted by gas proportional counting. By using vacuum box cartridge technology with rapid flow rates, sample preparation time is minimized.
Date: February 10, 2006
Creator: Maxwell, Sherrod, L. III
Partner: UNT Libraries Government Documents Department

Application of Empore{trademark} disk technology to environmental radiochemical analysis

Description: The costs associated with environmental restoration and waste management at both government and private facilities are burdensome, and continue to grow. The Department of Energy estimates that over one million samples, many containing radioactive components, will be analyzed per annum to support remediation programs at its 4000 sites. The development and implementation of new analytical technologies can significantly reduce the high costs associated with these programs. Disk solid-phase extraction technology has been proven to be highly effective for sample preparation in the analysis of organic compounds, waste waters, and other aqueous samples. Disk technology significantly improves sample throughput, while reducing secondary waste and costs. Moreover, many of the hazardous chemicals associated with traditional procedures are eliminated. This technology may be readily automated and lends itself to field applications. Through a Cooperative Research and Development Agreement, the 3M Company and Argonne National Laboratory are expanding this technology to address sample preparation and recovery of radionuclides from aqueous samples, i.e., surface, ground, and drinking waters. Disks have been developed which demonstrate high selectivity and great affinity for important radionuclides, including {sup 99}Tc, {sup 89/90}Sr, and {sup 226/228}Ra.
Date: December 31, 1995
Creator: Smith, L.L.; Orlandini, K.A.; Alvarado, J.S.; Hoffmann, K.M.; Seely, D.C. & Shannon, R.T.
Partner: UNT Libraries Government Documents Department

Radiological dose assessment of the disposal of NORM wastes via landspreading.

Description: Petroleum production activities sometimes result in the accumulation of naturally occurring radioactive materials (NORM) at elevated concentrations in by-product waste streams, such as scale and sludge. In the past, the petroleum industry commonly disposed of these wastes via landspreading, a practice consisting of spreading the waste over the soil surface and, sometimes, mixing it into the top layer of soil. Potential radiological doses to workers and the general public from landspreading of NORM waste have been assessed for a variety of scenarios, including the landspreading worker scenario and future residential, industrial, recreational, and agricultural scenarios. The exposure pathways evaluated include external radiation, inhalation of resuspended dust and radon, ingestion of soil and groundwater, and ingestion of contaminated foodstuff grown on the property. In general, potential doses to landspreading workers and members of the general public exposed through future recreational or agricultural use of the property are negligible. Potential doses to future residential or industrial users can vary greatly, depending on such factors as type of building construction, presence or absence of clean cover material, and on-site erosion rates. On the basis of the results presented in this paper, it is recommended that (a) any landspreading activity that would result in radium-226 concentrations in soil above 10 pCi/g be evaluated on a case-by-case basis to estimate potential future risk to the public and (b) states should consider policies to restrict future land use or advise future land owners where landspreading of NORM wastes has occurred.
Date: December 18, 1998
Creator: Smith, K. P.
Partner: UNT Libraries Government Documents Department

Generation and mobility of radon in soil. Technical report

Description: This study has confirmed large seasonal and daily variations of Rn in soil gas, developed models for the effects of temperature and moisture on air-water Rn partition, inhibited Rn diffusion from wet soil into sparse large air-filled pores and effects of diffusion into bedrock, demonstrated that organic matter is a major host for 226Ra in soils and that organic-bound Ra largely determines the proportion of 222Rn emanated to pore space, shown that in contrast 220Rn is emanated mainly from 224Ra in Fe-oxides, detected significant disequilibrium between 226Ra and 238U in organic matter and in some recent glacial soils, demonstrated by computer models that air convection driven by temperature differences is expected in moderately permeable soils on hillsides.
Date: May 1, 1993
Creator: Rose, A. W.; Jester, W. A. & Ciolkosz, E. J.
Partner: UNT Libraries Government Documents Department

Radium-226 and low pH in groundwater due to oxidation of authigenic pyrite; Savannah River Site, South Carolina

Description: The origin of elevated radium-226 in groundwater beneath a sanitary landfill at the Savannah River Site (SRS) was investigated. Nearly one hundred monitoring wells are developed in the Steed Pond Aquifer (SPA), which consists of 100-150 ft of Coastal Plain sand, iron oxides, and minor clay. Wells screened in the upper and middle portions of the aquifer have average Ra-226 between 0.5 and 2.5 pCi/L, and average pHs above 4.7. However, wells screened near the base of the aquifer exhibit higher average Ra-226 concentrations of 2.5 to 4.6 pCi/L, with some measurements exceeding the MCL of 5 pCi/L, and show average pHs of 4.1 to 4.7. These wells are not downgradient of the landfill, and are not impacted by landfill leachate. The Crouch Branch Confining Unit (CBCU) underlies the aquifer, and is composed partly of reduced gray/brown clay with lignite and authigenic pyrite. Gamma ray logs show that the SPA has low gamma counts, but the CBCU is consistently elevated. Groundwater with high radium/low pH also contains elevated sulfate concentrations. pH calculations indicate that sulfate is in the form of sulfuric acid. A model for the origin of elevated Ra-226 levels in deeper SPA wells envisions infiltration of oxygenated SPA groundwater into reduced pyritic CBCU sediments, with consequent oxidative pyrite dissolution, and acidification of groundwater. Then, naturally occurring CBCU radium dissolves, and mixes into the Steed Pond Aquifer.
Date: December 21, 2005
Creator: KUBILIUS, WALTER
Partner: UNT Libraries Government Documents Department

An Aerial Radiological Survey of the Portsmouth Gaseous Diffusion Plant and Surrounding Area, Portsmouth, Ohio

Description: An aerial radiological survey was conducted over the 16 square-mile (~41 square-kilometer) area surrounding the Portsmouth Gaseous Diffusion Plant. The survey was performed in August 2007 utilizing a large array of helicopter mounted sodium iodide detectors. The purpose of the survey was to update the previous radiological survey levels of the environment and surrounding areas of the plant. A search for a missing radium-226 source was also performed. Implied exposure rates, man-made activity, and excess bismuth-214 activity, as calculated from the aerial data are presented in the form of isopleth maps superimposed on imagery of the surveyed area. Ground level and implied aerial exposure rates for nine specific locations are compared. Detected radioisotopes and their associated gamma ray exposure rates were consistent with those expected from normal background emitters. At specific plant locations described in the report, man-made activity was consistent with the operational histories of the location. There was no spectral activity that would indicate the presence of the lost source.
Date: December 1, 2007
Creator: Moon, Namdoo
Partner: UNT Libraries Government Documents Department

Closure Report for Corrective Action Unit 117: Area 26 Pluto Disassembly Facility, Nevada Test Site, Nevada, Revision 0

Description: This Closure Report (CR) presents information supporting the closure of Corrective Action Unit (CAU) 117: Area 26 Pluto Disassembly Facility, Nevada Test Site, Nevada. This CR complies with the requirements of the Federal Facility Agreement and Consent Order that was agreed to by the State of Nevada; U.S. Department of Energy (DOE), Environmental Management; U.S. Department of Defense; and DOE, Legacy Management. Corrective Action Unit 117 comprises Corrective Action Site (CAS) 26-41-01, Pluto Disassembly Facility, located in Area 26 of the Nevada Test Site. The purpose of this CR is to provide documentation supporting the completed corrective actions and provide data confirming that the closure objectives for CAU 117 were met. To achieve this, the following actions were performed: • Review the current site conditions, including the concentration and extent of contamination. • Implement any corrective actions necessary to protect human health and the environment. • Properly dispose of corrective action and investigation wastes. • Document Notice of Completion and closure of CAU 117 issued by the Nevada Division of Environmental Protection. From May 2008 through February 2009, closure activities were performed as set forth in the Streamlined Approach for Environmental Restoration Plan for Corrective Action Unit 117, Area 26 Pluto Disassembly Facility, Nevada Test Site, Nevada. The purpose of the activities as defined during the data quality objectives process were: • Determine whether contaminants of concern (COCs) are present. • If COCs are present, determine their nature and extent, implement appropriate corrective actions, and properly dispose of wastes. Analytes detected during the closure activities were evaluated against final action levels to determine COCs for CAU 117. Assessment of the data generated from closure activities indicated that the final action levels were exceeded for polychlorinated biphenyls (PCBs) reported as total Aroclor and radium-226. A corrective action was implemented to remove ...
Date: June 1, 2009
Creator: Burmeister, Mark
Partner: UNT Libraries Government Documents Department

Characterization of Tank 23H Supernate Per Saltstone Waste Acceptance Criteria Analysis Requirements -2005

Description: Variable depth Tank 23H samples (22-inch sample [HTF-014] and 185-inch sample [HTF-013]) were pulled from Tank 23H in February, 2005 for characterization. The characterization of the Tank 23H low activity waste is part of the overall liquid waste processing activities. This characterization examined the species identified in the Saltstone Waste Acceptance Criteria (WAC) for the transfer of waste into the Salt-Feed Tank (SFT). The samples were delivered to the Savannah River National Laboratory (SRNL) and analyzed. Apart from radium-226 with an average measured detection limit of < 2.64E+03 pCi/mL, which is about the same order of magnitude as the WAC limit (< 8.73E+03 pCi/mL), none of the species analyzed was found to approach the limits provided in the Saltstone WAC. The concentration of most of the species analyzed for the Tank 23H samples were 2-5 orders of magnitude lower than the WAC limits. The achievable detection limits for a number of the analytes were several orders of magnitude lower than the WAC limits, but one or two orders of magnitude higher than the requested detection limits. Analytes which fell into this category included plutonium-241, europium-154/155, antimony-125, tin-126, ruthenium/rhodium-106, selenium-79, nickel-59/63, ammonium ion, copper, total nickel, manganese and total organic carbon.
Date: May 5, 2005
Creator: Oji, L
Partner: UNT Libraries Government Documents Department

F-Area Acid/Caustic Basin groundwater monitoring report. Second quarter 1995

Description: During second quarter 1995, samples from the FAC monitoring wells at the F-Area Acid/Caustic Basin were collected and analyzed for herbicides/pesticides, indicator parameters, metals, nitrate, radionuclide indicators, volatile organic compounds, and other constituents. Piezometer FAC 5P and monitoring well FAC 6 were dry and could not be sampled. New monitoring wells FAC 9C, 10C, 11C, and 12C were completed in the Barnwell/McBean aquifer and were sampled for the first time during third quarter 1994 (second quarter 1995 is the fourth of four quarters of data required to support the closure of the basin). Analytical results that exceeded final Primary Drinking Water Standards (PDWS) or Savannah River Site (SRS) Flag 2 criteria such as the SRS turbidity standard of 50 NTU during the quarter were as follows: gross alpha exceeded the final PDWS and aluminum, iron, manganese, and radium-226 exceeded the SRS Flag 2 criteria in one or more of the FAC wells. Turbidity exceeded the SRS standard (50 NTU) in well FAC 3. Groundwater flow direction in the water table beneath the F-Area Acid/Caustic Basin was to the west at a rate of 1300 feet per year. Groundwater flow in the Barnwell/McBean was to the northeast at a rate of 50 feet per year.
Date: September 1995
Partner: UNT Libraries Government Documents Department

Environmental surveillance results for 1995 for the Hazelwood Interim Storage Site

Description: This memorandum presents and interprets analytical results and measurements obtained as part of the 1995 environmental surveillance program for the Hazelwood Interim Storage Site (HISS) under the Formerly Utilized Sites Remedial Action Program (FUSRAP). The discussion provides a comparative analysis of average historical background conditions and applicable regulatory criteria to the 1995 results reported for external gamma radiation and for samples from the media investigated (air, surface water, sediment, groundwater, and stormwater). Results from the 1995 environmental surveillance program at HISS indicate that, with the exception of thorium-230 in streambed sediment, applicable US Department of Energy (DOE) guidelines were not exceeded for any measured parameter or for any dose calculated for potentially exposed members of the general public. In the absence of sediment guidelines, DOE soil guidelines serve as a standard of comparison for data obtained from stream bed sediment; two samples from downstream locations contained concentrations of thorium-230 that exceeded DOE soil guidelines. All stormwater sample results were in compliance with permit-specified limits. Other radioactive materials include radium 226 and natural uranium.
Date: June 1, 1996
Creator: McCague, J.C.
Partner: UNT Libraries Government Documents Department

Treatment methods and comparative risks of thorium removal from waste residues

Description: This study was done to examine the risks of remediation and the effectiveness of removal methods for thorium and its associated radioactive decay products from various soils and wastes associated with DOE`s Formerly Utilized Sites Remedial Action Program (FUSRAP). Removal of {sup 230}Th from uranium process residues would significantly reduce the buildup of {sup 226}Ra (half-life of 1600 years), and since {sup 230}Th concentrations at most of the important sites greatly exceed the {sup 226}Ra concentrations, such removal would reduce the accumulation of additional radiation risks associated with {sup 226}Ra and its products; and, if treatment also removed {sup 226}Ra, these risks could be mitigated even further. Removal of {sup 232}Th from thorium process residues would remove the source material for {sup 228}Ra, and since {sup 228}Ra has a half-life of 5.76 years, its control at FUSRAP sites could be done with land use controls for the 30--50 years required for {sup 228}Ra and the risks associated with its decay products to decay away. It must be recognized, however, that treatment methods invariably require workers to process residues and waste materials usually with bulk handling techniques. These processes expose workers to the radioactivity in the materials, therefore, workers would incur radiological risks in addition to industrial accident risks. An important question is whether the potential reduction of future radiological risks to members of the public justifies the risks that are incurred by remediation workers due to handling materials. This study examines, first, the effectiveness of treatment and then the risks that would be associated with remediation.
Date: July 1, 1997
Creator: Porter, R.D.; Hamby, D.M. & Martin, J.E.
Partner: UNT Libraries Government Documents Department

Letter report: Radiological analysis of Oak Ridge Y-12 plant groundwater data

Description: The Y-12 Plant groundwater radiological data bases have been analyzed to determine whether historical and current data is suitable for unqualified release to various user groups. User groups include those who routinely compare results to reference standards or regulatory levels, conduct hydrogeological transport studies, conduct statistical analyses and conduct risk assessment studies. The overall methodology used for the radiological analysis is to check whether results are consistent with chemical and physical expectations, plant operational history and, where applicable, with results from other sites. For example, the relationship among isotopes in a decay chain are predictable if no unusual sources for a particular isotope in the chain exists, the time history is known, and differential removal or concentration mechanisms for a particular isotope are understood or do not exist. Similarly, background concentrations for radioisotopes (e.g., {sup 238}U, {sup 234}U, {sup 235}U, {sup 230}Th, {sup 226}Ra, etc.) should be consistent with those obtained in other studies given similar mineralogical or hydrogeological conditions at the Y-12 Plant. If the analysis results in lack of agreement between results and expectations based on known relationships, plant operations and transport parameters, then results are investigated further.
Date: June 22, 1995
Creator: Walsh, P.
Partner: UNT Libraries Government Documents Department

Radium separation through complexation by aqueous crown ethers and ion exchange or solvent extraction

Description: The effect of three water-soluble, unsubstituted crown ethers (15-crown-5 (15C5), 18-crown-6 (18C6) and 21-crown-7 (21C7)) on the uptake of Ca, Sr, Ba and Ra cations by a sulfonic acid cation exchange resin, and on the extraction of the same cations by xylene solutions of dinonylnaphthalenesulfonic acid (HDNNS) from aqueous hydrochloric acid solutions has been investigated. The crown ethers enhance the sorption of the larger cations by the ion exchange resin, thereby improving the resin selectivity over calcium, a result of a synergistic interaction between the crown ether and the ionic functional groups of the resin. Similarly, the extraction of the larger alkaline earth cations into xylene by HDNNS is strongly synergized by the presence of the crown ethers in the aqueous phase. Promising results for intra-Group IIa cation separations have been obtained using each of the three crown ethers as the aqueous ligands and the sulfonic acid cation exchange resin. Even greater separation factors for the radium-calcium couple have been measured with the crown-ethers and HDNNS solutions in the solvent extraction mode. The application of the uptake and extraction results to the development of radium separation schemes is discussed and a possible flowchart for the determination of {sup 226}Ra/{sup 228}Ra in natural waters is presented.
Date: November 1, 1997
Creator: Chiarizia, R.; Dietz, M.L.; Horwitz, E.P. & Burnett, W.C.
Partner: UNT Libraries Government Documents Department