The loop prominence of May 13, 1971 and its associated effects

A study is presented about the formation of a loop prominence system (LPS) on May 13, 1971. The development of the phenomenon in found the follow the model of Jefferies and Orrall, and was associated with small radio bursts and several kind SID. From the spectral analysis a temperature of 13200 K has been deduced and a density of hydrogen atoms n(H) = 10¹⁰ cm⁻⁸ estimated. The existence of inclined emissions probably produced by rotatory motions is discussed. From the radio-data analysis it was inferred that an impulsive and a thermal component were present, the length of the emitting plasma cloud was found to be about 56000 Km. The LPS appeared, in accordance to previous results, in a región producing proton fiares. The paper in full will be published in Solar Physics.Asociación Argentina de Astronomí

The loop prominence of May 13, 1971 and its associated effects

A study is presented about the formation of a loop prominence system (LPS) on May 13, 1971. The development of the phenomenon in found the follow the model of Jefferies and Orrall, and was associated with small radio bursts and several kind SID. From the spectral analysis a temperature of 13200 K has been deduced and a density of hydrogen atoms n(H) = 10¹⁰ cm⁻⁸ estimated. The existence of inclined emissions probably produced by rotatory motions is discussed. From the radio-data analysis it was inferred that an impulsive and a thermal component were present, the length of the emitting plasma cloud was found to be about 56000 Km. The LPS appeared, in accordance to previous results, in a región producing proton fiares. The paper in full will be published in Solar Physics.Asociación Argentina de Astronomí

The loop prominence of May 13, 1971 and its associated effects

A study is presented about the formation of a loop prominence system (LPS) on May 13, 1971. The development of the phenomenon in found the follow the model of Jefferies and Orrall, and was associated with small radio bursts and several kind SID. From the spectral analysis a temperature of 13200 K has been deduced and a density of hydrogen atoms n(H) = 10¹⁰ cm⁻⁸ estimated. The existence of inclined emissions probably produced by rotatory motions is discussed. From the radio-data analysis it was inferred that an impulsive and a thermal component were present, the length of the emitting plasma cloud was found to be about 56000 Km. The LPS appeared, in accordance to previous results, in a región producing proton fiares. The paper in full will be published in Solar Physics.Asociación Argentina de Astronomí

Runoff and sediment yield model for predicting nuclide transport in watersheds using BIOTRAN

The environmental risk simulation model BIOTRAN was interfaced with a series of new subroutines (RUNOFF, GEOFLX, EROSON, and AQUIFER) to predict the movement of nuclides, elements, and pertinent chemical compounds in association with sediments through lateral and channel flow of runoff water. In addition, the movement of water into and out of segmented portions of runoff channels was modeled to simulate the dynamics of moisture flow through specified aquifers within the watershed. The BIOTRAN soil water flux subroutine, WATFLX, was modified to interface the relationships found in the SPUR model for runoff and sediment transport into channels with the particle sorting relationships to predict radionuclide enrichment and movement in watersheds. The new subroutines were applied specifically to Mortandad Canyon within Los Alamos National Laboratory by simultaneous simulation of eight surface vegetational subdivisions and associated channel and aquifer segments of this watershed. This report focuses on descriptions of the construction and rationale for the new subroutines and on discussing both input characteristics and output relationships to known runoff events from Mortandad Canyon. Limitations of the simplified input on model behavior are also discussed. Uranium-238 was selected as the nuclide for demonstration of the model because it could be assumed to be homogeneously distributed over the watershed surface. 22 refs., 18 figs., 9 tabs

A spatially-dynamic preliminary risk assessment of the American peregrine falcon at the Los Alamos National Laboratory (version 1)

The Endangered Species Act and the Record of Decision on the Dual Axis Radiographic Hydrodynamic Test Facility at the Los Alamos National Laboratory require protection of the American peregrine falcon. A preliminary risk assessment of the peregrine was performed using a custom FORTRAN model and a geographical information system. Estimated doses to the falcon were compared against toxicity reference values to generate hazard indices. Hazard index results indicated no unacceptable risk to the falcon from the soil ingestion pathway, including a measure of cumulative effects from multiple contaminants that assumes a linear additive toxicity type. Scaling home ranges on the basis of maximizing falcon height for viewing prey decreased estimated risk by 69% in a canyons-based home range and increased estimated risk by 40% in a river-based home range. Improving model realism by weighting simulated falcon foraging based on distance from potential nest sites decreased risk by 93% in one exposure unit and by 82% in a second exposure unit. It was demonstrated that choice of toxicity reference values can have a substantial impact on risk estimates. Adding bioaccumulation factors for several organics increased partial hazard quotients by a factor of 110, but increased the mean hazard index by only 0.02 units. Adding a food consumption exposure pathway in the form of biomagnification factors for 15 contaminants of potential ecological concern increased the mean hazard index to 1.16 ({+-} 1.0), which is above the level of acceptability (1.0). Aroclor-1254, dichlorodiphenyltrichlorethane (DDT) and dichlorodiphenylethelyne (DDE) accounted for 81% of the estimated risk that includes soil ingestion and food consumption Contaminant pathways and a biomagnification component. Information on risk by specific geographical location was generated, which can be used to manage contaminated areas, falcon habitat, facility siting, and/or facility operations. 123 refs., 10 figs., 2 tabs

Preliminary risk assessment of the Mexican Spotted Owl under a spatially-weighted foraging regime at the Los Alamos National Laboratory

The Record of Decision on the Dual Axis Radiographic Hydrodynamic Test Facility at the Los Alamos National Laboratory requires that the Department of Energy takes special precautions to protect the Mexican Spotted Owl (Strix occidentalis lucida). In order to do so, risk to the owl presented by radiological and nonradiological contaminants must be estimated. A preliminary risk assessment on the Mexican Spotted Owl in two Ecological Exposure Units (EEUs) was performed using a modified Environmental Protection Agency Quotient method, the FORTRAN model ECORSK4, and a geographic information system. Estimated doses to the owl under a spatially-weighted foraging regime were compared against toxicological reference doses generating hazard indices (HIs) and hazard quotients (HQs) for three risk source types. The average HI was 0.20 for EEU-21 and 0.0015 for EEU-40. Under the risk parameter assumptions made, hazard quotient results indicated no unacceptable risk to the owl, including a measure of cumulative effects from multiple contaminants that assumes a linear additive toxicity type. An HI of 1.0 was used as the evaluative criteria for determining the acceptability of risk. This value was exceeded (1.06) in only one of 200 simulated potential nest sites. Cesium-137, Ni, {sup 239}Pu, Al and {sup 234}U we`re among the constituents with the highest partial HQs. Improving model realism by weighting simulated owl foraging based on distance from potential nest sites decreased the estimated risk by 72% (0.5 HI units) for EEU-21 and by 97.6% (6.3E-02 HI units) for EEU-40. Information on risk by specific geographical location was generated, which can be used to manage contaminated areas, owl habitat, facility siting, and/or facility operations in order to maintain risk from contaminants at acceptably low levels

Preliminary Risk Assessment of the Southwestern Willow Flycatcher (Empidonax traillii extimus) at the Los Alamos National Laboratory

The southwestern willow flycatcher (Empidonax traillii extimus) is the fourth threatened or endangered species to undergo a preliminary assessment for estimating potential risk from environmental contaminants at the Los Alamos National Laboratory. The assessments are being conducted as part of a three-year project to develop a habitat management plan for threatened and endangered species and species of concern at the Laboratory. For the preliminary assessment, estimated doses were compared against toxicity reference values to generate hazard indices (HIs). This assessment included a measure of cumulative effects from multiple contaminants (radionuclides, metals, and organic chemicals) to 100 simulated nest sites located within flycatcher potential habitat. Sources of contaminant values were 10,000-ft{sup 2} grid cells within an Ecological Exposure Unit (EEU). This EEU was estimated around the potential habitat and was based on the maximum home range for the fly catcher identified in the scientific literature. The tools used included a custom FORTRAN program, ECORSK5, and a geographic information system. Food consumption and soil ingestion contaminant pathways were addressed in the assessment. Using a four-category risk evaluation, HI results indicate no appreciable impact is expected to the southwestern willow flycatcher. Information on risk by specific geographical location was generated, which can be used to manage contaminated areas, flycatcher habitat, facility siting, and/or facility operations in order to maintain low levels of risk from contaminants

Second annual review update preliminary risk assessment of federally protected species at the Los Alamos National Laboratory

In FY96 and FY97, preliminary assessments were conducted of the potential risk from legacy waste to the American peregrine falcon (Falco peregrimus), the bald eagle (Haliaeetus leucocephalus), and the Mexican spotted owl (Strix occidentalis lucida). Estimated doses were compared against toxicity reference values (TRVs) to generate hazard indices that included a measure of cumulative effects from multiple contaminants (radionuclides, metals, and organic chemicals). The tools used included a custom FORTRAN code ECORSK, and a geographic information system. The assessments originally included only the soil ingestion contaminant pathway. Since the initial assessments, a food consumption contaminant pathway has been added, bioaccumulation and biomagnification of some contaminants have been factored into the food consumption pathway, and some of the TRVs against which estimated doses are compared have been changed to values which relate more closely to the Aves taxonomical class. With these and other more subtle improvements in model input parameters, ECORSK has been revised and the model has been re-executed for the owl and peregrine exposure units that originally generated the highest risk indices. This report contains the updated results. On average, results indicate a small potential for impact to the peregrine falcon, but no appreciable impact to the spotted owl nor the bald eagle. The original reports cited in this document should be consulted for details on methods