Search Results

Advanced search parameters have been applied.
open access

Comparison of Ambient Radon Concentrations in Air in the Northern Mojave Desert from Continuous and Integrating Instruments

Description: As part of a program to characterize and baseline environmental parameters, ambient radon-222 (Rn) monitoring was conducted in the rural community of Amargosa Valley, NV, the closest community to Yucca Mountain. Passive integrating and continuous Rn monitoring instruments were deployed adjacent to the Community Environmental Monitoring Program (CEMP) station in Amargosa Valley. The CEMP station provided real-time ambient gamma exposure and meteorological data used to correct the integrated Rn m… more
Date: May 18, 2010
Creator: Shafer, David S.; McGraw, David; Karr, Lynn H.; McCurdy, Greg; Kluesner, Tammy L.; Gray, Karen J. et al.
Partner: UNT Libraries Government Documents Department
open access

Indoor Radon and Its Decay Products: Concentrations, Causes, and Control Strategies

Description: This report is an introduction to the behavior of radon 222 and its decay products in indoor air. This includes review of basic characteristics of radon and its decay products and of features of the indoor environment itself, all of which factors affect behavior in indoor air. The experimental and theoretical evidence on behavior of radon and its decay products is examined, providing a basis for understanding the influence of geological, structural, and meteorological factors on indoor concentr… more
Date: January 1, 1990
Creator: Nero, A. V.; Gadgil, A. J.; Nazaroff, W. W. & Revzan, K. L.
Partner: UNT Libraries Government Documents Department
open access

Preliminary results from the lunar prospector alpha particle spectrometer

Description: The Lunar Prospector Alpha Particle Spectrometer (LP APS) builds on Apollo heritage and maps the distribution of outgassing sites on the Moon. The APS searches for lunar surface gas release events and maps their distribution by detecting alpha particles produced by the decay of gaseous radon-222 (5.5 MeV, 3.8 day half-life) and solid polonium-210 (5.3 MeV, 138 day half-life, but remains on the surface with a 21 year half-life as lead-210), which are radioactive daughters from the decay of urani… more
Date: January 1, 2001
Creator: Lawson, S. L. (Stefanie L.)
Partner: UNT Libraries Government Documents Department
open access

Development of Radon-222 as a Natural Tracer for Monitoring the Remediation of NAPL Contamination in the Subsurface.

Description: The objective of this research is to develop a unique method for using naturally occurring radon-222 as an inexpensive partitioning tracer for locating and quantitatifying nonaqueous phase liquid (NAPL) contamination in the subsurface, and assessing the effectiveness of NAPL remediation. Laboratory, field, and modeling studies are being performed to evaluate this technique, and to develop methods for its successful implementation in practice.
Date: June 1, 1999
Creator: Semprini, Lewis
Partner: UNT Libraries Government Documents Department
open access

Development of Radon-222 as Natural Tracer for Monitoring the Remediation of NAPL in the Subsurface

Description: Naturally occurring 222-radon in ground water can potentially be used as an in situ partitioning tracer to characterize dense nonaqueous phase liquid (DNAPL) saturations. The static method involves comparing radon concentrations in water samples from DNAPL-contaminated and non-contaminated portions of an aquifer. During a push-pull test, a known volume of test solution (radon-free water containing a conservation tracer) is first injected (''pushed'') into a well; flow is then reversed and the t… more
Date: February 27, 2003
Creator: Davis, Brian M.; Semprini, Lewis & Istok, Jonathan
Partner: UNT Libraries Government Documents Department
open access

Concentrations of dissolved radon-222 in water from selected wells and springs in Idaho, 1989-91

Description: Concentrations of dissolved radon-222, a naturally occurring radioactive gas, are found in water in Idaho. The U.S. Geological Survey collected water samples for radon-222 analyses from 338 Idaho wells and springs during 1989-91. These water samples were collected as part of ongoing monitoring programs with the Idaho Department of Water Resources and the U.S. Department of Energy. Concentrations of dissolved radon-222 in 372 of the water samples ranged from -58{+-}30 to 5,715{+-}66 picocuries p… more
Date: November 1, 1994
Creator: Cecil, L. D.; Parliman, D. J.; Edwards, D. D. & Young, H. W.
Partner: UNT Libraries Government Documents Department
open access

Study of temporal variation of radon concentrations in public drinking water supplies

Description: The Environmental Protection Agency (EPA) has proposed a Maximum Contaminant Level (MCL) for radon-222 in public drinking water supplies of 300 pCi/L. Proposed monitoring requirements include collecting quarterly grab samples for the first year, then annual samples for the remainder of the compliance cycle provided first year quarterly samples average below the MCL. The focus of this research was to study the temporal variation of groundwater radon concentrations to investigate how reliably one… more
Date: December 31, 1995
Creator: York, E. L.
Partner: UNT Libraries Government Documents Department
open access

Radon entry into basements: Approach, experimental structures, and instrumentation of the small structures research project

Description: We describe the experimental approach, structures, and instrumentation of a research project on radon generation and transport in soil and entry into basements. The overall approach is to construct small precisely-fabricated basements in areas of different geology and climate, to control the pressures and ventilation rates in the structures, and to monitor radon concentrations and other relevant parameters over a period of one year or more. Two nearly air-tight structures have been constructed … more
Date: February 1, 1992
Creator: Fisk, W. J.; Modera, M. P.; Sextro, R. G.; Garbesi, K.; Wollenberg, H. A.; Narasimhan, T. N. et al.
Partner: UNT Libraries Government Documents Department
open access

The Effect of Steady Winds on Radon-222 Entry from soil into houses

Description: Wind affects the radon-222 entry rate from soil into buildings and the resulting indoor concentrations. To investigate this phenomenon, we employ a previously tested three-dimensional numerical model of soil-gas Bow around houses, a commercial computational fluid dynamics code, an established model for determining ventilation rates in the presence of wind, and new wind tunnel results for the ground-surface pressure field caused by wind. These tools and data, applied under steady-state condition… more
Date: October 1, 1994
Creator: Riley, W. J.; Gadgil, A. J.; Bonnefous, Y. C. & Nazaroff, W. W.
Partner: UNT Libraries Government Documents Department
open access

Short- and long-lived radionuclide particle size measurements in a uranium mine

Description: The radon-222 progeny and long-lived radionuclide measurements were done in a wet underground uranium mine in Saskatchewan, Canada, on Nov. 8-12, 1995. Radon-222 in the mine varied from 2 kBq/m{sup 3} at 90 m below surface to 12 kBq/m{sup 3} in the mining areas, 240 m below surface. Radon-222 progeny activity and potential alpha energy concentration appear affected by the airborne particle number concentration and size distribution. Particle number was up to 200x10{sup 3}/cm{sup 3}. Only an acc… more
Date: April 1, 1997
Creator: Tu, Keng-Wu; Fisenne, I.M. & Hutter, A.R.
Partner: UNT Libraries Government Documents Department
open access

Radiological air quality in a depleted uranium storage vault

Description: The radiological air quality of two storage vaults, one with depleted uranium (DU) and one without, was evaluated and compared. The intent of the study was to determine if the presence of stored DU would significantly contribute to the gaseous/airborne radiation level compared to natural background. Both vaults are constructed out of concrete and are dimensionally similar. The vaults are located on the first floor of the same building. Neither vault has air supply or air exhaust. The doors to b… more
Date: March 1, 1999
Creator: Robinson, T. & Cucchiara, A.L.
Partner: UNT Libraries Government Documents Department
open access

A detailed examination of the chemical, hydrological, and geological properties influencing the mobility of {sup 222}radon and parent radionuclides in groundwater

Description: This study examines hydrological, geological and geochemical controls on {sup 222}Rn variability in groundwater in the Front Range of Colorado. Specific objectives of the study are: (1) to determine if there are any correlations or spatial relationships between {sup 222}Rn and the geological, geochemical and hydrogeological data; and (2) to determine whether it is geochemically reasonable for observed {sup 222}Rn levels to be the result of U and {sup 226}Ra accumulation by fracture filling mine… more
Date: October 10, 1996
Creator: Sexsmith, Kelly Sara
Partner: UNT Libraries Government Documents Department
open access

Residence times of fine tropospheric aerosols as determined by {sup 210}Pb progeny.

Description: Fine tropospheric aerosols can play important roles in the radiative balance of the atmosphere. The fine aerosols can act directly to cool the atmosphere by scattering incoming solar radiation, as well as indirectly by serving as cloud condensation nuclei. Fine aerosols, particularly carbonaceous soots, can also warm the atmosphere by absorbing incoming solar radiation. In addition, aerosols smaller than 2.5 {micro}m have recently been implicated in the health effects of air pollution. Aerosol-… more
Date: October 5, 1999
Creator: Marley, N. A.; Gaffney, J. S.; Drayton, P. J.; Cunningham, M. M.; Mielcarek, C.; Ravelo, R. et al.
Partner: UNT Libraries Government Documents Department
open access

Intercomparison of active, passive and continuous instruments for radon and radon progeny measurements in the EML chamber and test facility

Description: Results are presented from the Fifth Intercomparison of Active, Passive and Continuous Instruments for Radon and Radon Progeny Measurements conducted in the EML radon exposure and test facility in May 1996. In total, thirty-four government, private and academic facilities participated in the exercise with over 170 passive and electronic devices exposed in the EML test chamber. During the first week of the exercise, passive and continuous measuring devices were exposed (usually in quadruplicate)… more
Date: October 1, 1996
Creator: Scarpitta, S.C.; Tu, K.W.; Fisenne, I.M.; Cavallo, A. & Perry, P.
Partner: UNT Libraries Government Documents Department
open access

Well Test Summary and Results, January 18-24, 1984, Well 34-7B (Lady Linda). Appendix A, B, C, and D

Description: Results of analysis of your seven samples collected 18 through 21 January, 1984 are attached. All analyses were performed using standard water analysis methodologies. Radon-222 was determined on samples originally submitted for routine chemical analysis. These samples were delivered in partially-filled polyethylene bottles. Radon determinations were performed 4 February, 1984, by outgassing followed by scintillation counting. Calculation of results includes factors to correct for decay of radon… more
Date: January 1, 1985
Partner: UNT Libraries Government Documents Department
open access

A study of radon-222 concentrations in North Carolina groundwater

Description: The groundwater of 400 North Carolina homes was sampled to ascertain the distribution and extent of {sup 222}Rn in North Carolina groundwater. Arithmetic mean (AM) and geometric mean (GM) concentrations of 1,816 pCi L{sup {minus}1} and 656 pCi L{sup {minus}1} were found for the state. These results indicate that two-thirds of 114{degree}C. homes served by groundwater exceed the EPA proposed 300 pCi L{sup {minus}1} maximum contaminant level (MCL). Only 2% of NC homes exceeded 10,000 pCi L-1. The… more
Date: December 31, 1992
Creator: Evans, J. P.
Partner: UNT Libraries Government Documents Department
open access

Characterization of the Radon Source in North-Central Florida. Final Report Part 1 -- Final Project Report; Final Report Part 2 -- Technical Report

Description: This report contains two separate parts: Characterization of the Radon Source in North-Central Florida (final report part 1 -- final project report); and Characterization of the Radon Source in North-Central Florida (technical report). The objectives were to characterize the radon 222 source in a region having a demonstrated elevated indoor radon potential and having geology, lithology, and climate that are different from those in other regions of the U.S. where radon is being studied. Radon av… more
Date: December 1, 1997
Partner: UNT Libraries Government Documents Department
open access

Potential increases in natural radon emissions due to heating of the Yucca Mountain rock mass

Description: Heating of the rock mass by the spent fuel in the proposed repository at Yucca Mountain will cause extra amounts of natural radon to diffuse into the fracture system and to migrate faster to the accessible environment. Indeed, free-convection currents due to heating will act to shorten the radon travel times and will cause larger releases than would be possible under undistributed conditions. To estimate the amount of additional radon released due to heating of the Yucca Mountain rock mass, we … more
Date: February 1, 1992
Creator: Pescatore, C. & Sullivan, T.M.
Partner: UNT Libraries Government Documents Department
open access

[The determination of {sup 222}Rn flux from soils based on {sup 210}Pb and {sup 226}Ra disequilibrium]. Progress report

Description: The emanating fraction of radon in soils from the southern part of the United States is about 40% greater than in those from the northern part. The mean {sup 226}Ra activity in the southern soils is also slightly higher and as a consequence the {sup 222}Rn flux derived from the top 50 cm. is greater in the southern samples. We tentatively attribute these observations to the greater degree of weathering associated with the pre-glacial age of the parent material of many of the southern soils. The… more
Date: December 31, 1991
Creator: Turekian, K. K.
Partner: UNT Libraries Government Documents Department
open access

Release of radon contaminants from Yucca Mountain: The role of buoyancy driven flow

Description: The potential for the repository heat source to promote buoyancy driven flow and thereby cause release of radon gas out of Yucca Mountain has been examined through a critical review of the theoretical and experimental studies of this process. The review indicates that steady-state buoyancy enhanced release of natural radon and other contaminant gases should not be a major concern at Yucca Mountain. Barometric pumping and wind pumping are identified as two processes that will have a potentially … more
Date: February 1, 1994
Creator: Sullivan, T.M. & Pescatore, C.
Partner: UNT Libraries Government Documents Department
open access

Ambient Radon-222 Monitoring in Amargosa Valley, Nevada

Description: As part of a program to characterize and baseline selected environmental parameters in the region around the proposed repository at Yucca Mountain, Nevada, ambient radon-222 monitoring was conducted in the rural community of Amargosa Valley, the community closest to the proposed repository site. Passive integrating radon monitors and a continuous radon monitoring instrument were deployed adjacent to the Community Environmental Monitoring Program (CEMP) (http://www.cemp.dri.edu/index.html) stati… more
Date: June 5, 2008
Creator: Karr, L. H.; Tappen, J. J.; Shafer, D. & Gray, K. J.
Partner: UNT Libraries Government Documents Department
open access

A Study of the Emanation Method for the Determination of the Surface Area of Thorium Oxide

Description: The surface areas of several thorium oxide and thorium oxide--uranium oxide preparations were measured by the emanation method. The radioactive gas- counting system employed is described, and a discussion of the procedure for converting counting data to terms of emanating power and finally to surface area values is given. Surface area values by the emanation method were compared with BET values from like samples. The difference between values obtained by the two methods was attributed to the ef… more
Date: April 1, 1961
Creator: Skladzien, S.B.
Partner: UNT Libraries Government Documents Department
open access

A portable battery-powered continuous airborne {sup 222}Rn sampler

Description: The Polyport, designed at the Environmental Measurements Laboratory (EML) for deployment in atmospheric balloons or remote areas, was laboratory and field tested to determine its effectiveness in collecting {sup 222}Rn gas in dry and humid air. Twelve 6-cm long tubes containing 0.4 g of Carboxen{trademark}-564 a hydrophobic beaded carbon molecular sieve (BCMS) material efficiently adsorbs airborne {sup 222}Rn under dynamic sampling conditions of 1--2 hr duration. The exposed sorbent is later we… more
Date: April 1, 1998
Creator: Scarpitta, S. & Kadnar, M.
Partner: UNT Libraries Government Documents Department
open access

Radon Measurements at the Molten Salt Reactor Experiment (MSRE) Facility from August 1997 through April 1998

Description: From August 1997 through April 1998, radon and radon progeny measurements were collected at the Molten Salt Reactor Experiment (MSRE) facility at Oak Ridge National Laboratory. The purpose of the measurements was to determine the baseline concentrations of 222Rn (radon), 220Rn (thoron), and their progeny in the air at selected points with emphasis on the characterization of 220Rn and its daughter products in the high bay area. The daughter product concentrations ranged from the equivalent of ap… more
Date: April 1, 1999
Creator: Coleman, R.L.
Partner: UNT Libraries Government Documents Department
Back to Top of Screen