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Uranium, U, as a radiological and chemically toxic element has detrimental impacts on human health when ingested at elevated concentration in water. Effluents from an underground gold mine located in the head water region of the Rietspruit contaminated the stream with waterborne uranium. The Rietspruit is a tributary of the Vaal River and subsequently flows through residential and agricultural land. Water samples from the stream were collected and analysed using inductively coupled plasma mass spectrometry to determine the concentrations of dissolved U. The maximum concentration of U recorded was 781.9 µg/L at the mine from where it decreases with growing distance from the mine. Results from calculations showed that the maximum annual effective dose at the mine was above the regulatory limit for public exposure for all age groups. The radiological risk associated with consumption of untreated water from the Rietspruit is lower than the chemical risk. The chemical risk ranges from 0 to 37.2 while the highest life-time cancer risk was 1.7 E-03 for morbidity cancer risk and 1.1 E-03 for mortality cancer risk. The chemical risk analysis showed that within 24 km of downstream of the mine, stream users are exposed to toxic U levels. Therefore, adequate interventions by relevant government agencies are required. [ABSTRACT FROM AUTHOR]

The exposure of residents to large volumes of uraniferous mine waste deposits scattered across densely populated areas in the South African goldfields has long been identified as a potential health threat. To quantify this threat for selected locations numerous studies determined concentration levels of uranium and other radionuclides in different environmental media of the Witwatersrand basin including streams, soils, tailings deposits, mine water effluents, fluvial sediments, aquatic organisms as well as in the food chain (fish, cattle, crops, vegetables etc.). This paper describes how the secondary data were extracted from various sources in order to map the spatial extent and intensity of uranium pollution in selected goldfields and to quantify associated exposure of residents. Steps included geo-referencing, normalisation against selected benchmark values, and superimposition of complementary data sets in GIS. For easing access to the data base for non-GIS experts a virtual geographic environment (VGE) was used, offering updated satellite imagery and additional functionality that aided in modelling exposure of target populations. Exposure pathways considered here include ingestion of polluted water, food and soil (geophagia) as well as the inhalation of wind-blown tailings dust. In addition, anecdotal evidence and media-based reports on mining-related pollution and impacts were captured. Maps derived from the VGE were used to identify hot spots of radioactive pollution aiding the selection of suitable sampling sites for a screening survey on U-uptake by exposed residents using hair as a bio-indicator. • Thousands of point data on radioactive contamination were compiled in one of the largest databases of its kind in SA • Displaying georeferenced and normalised data revealed distinct spatial patterns and hot spots of U and Ra pollution • Linking pollution sources to settlements via a range of pathways allowed assessing the potential exposure of residents • Easy to operate the system facilitates public participation and provides scientific support for political decision making • By adding data as they become available the system is continuously expanded and maintained current [ABSTRACT FROM AUTHOR]

The primary objective of the research was to investigate the mailing practices and filing methods in a computer support or administrative environment involving the resulting abuse of paper. In applied research, an exploratory investigation focused on selected higher education institutions in Gauteng with a structured questionnaire as measuring instrument. In the analysis and interpretations of the findings, correlation and cross-tabulation on all sets of variables determined whether any meaningful associations could be found. The investigation indicated that the war against paper abuse is not over by any means. Perceptions regarding a paperless office and assumptions that technology could assist organisations to combat paper abuse were unfounded, mainly because of a lack of guidance, training interventions and control measures. Consequently, follow-up research is presently conducted whereby models will be designed and implemented concomitant with specified computer software features in order to counteract the abuse of paper and facilitate the effective use of information and communication technology interfaced work processes and procedures. This article focuses only on the electronic mail and filing components of the investigation. [ABSTRACT FROM AUTHOR]