[en] The recently concluded Comprehensive Test Ban Treaty (CTBT) envisages four monitoring techniques, namely, seismic, hydroacoustic, infrasound (microbarographic), and radionuclide as one of the requirements for compliance verification. Under Article IV of the CTBT, these four systems form part of the International Monitoring System (IMS). The verification tasks associated with the CTBT are technologically the most advanced and go further than any other existing treaty

[en] The volume presented contains papers presented at the Second Special Symposium on Natural Radiation Environment held at Bombay, India, during January 1981. The papers deal with such topics as : 1)high natural radiation background areas; 2)environmental natural radioactivity; 3)measurement techniques; 4)technologically enhanced radioactivity; 5)indoor radiation environment; 6)radon and daughters in ambient air, and 7)applications in Geosciences. Each of the 87 papers presented has been abstracted and indexed for the U.S. Department of Energy Technical Information Center's Energy Data Base

[en] The volume presented contains papers presented at the Second Special Symposium on Natural Radiation Environment held at Bombay, India, during January 1981. The papers deal with such topics as: 1)high natural radiation background areas; 2)environmental natural radioactivity; 3)measurement techniques; 4)technologically enhanced radioactivity; 5)indoor radiation environment; 6)radon and daughters in ambient air; and 7)applications in Geosciences. Each of the 87 papers presented has been abstracted and indexed for the U.S. Department of Energy Technical Information Center's Energy Data Base

[en] Forty-five samples of coal fly ash from about 30 thermal power stations and 11 samples of coal from 7 power stations were analysed by ED-XRF; additional analyses by INAA are in progress. These samples were obtained during an earlier study on technologically enhanced natural radioactivity due to coal-fired power stations. The results showed that the average contents of S, Cu, Zn and As in Indian coals are low and that there exists some enrichment from coal fly ash for elements such as Cu and Zn. The analytical procedures for both ED-XRF and INAA were revalidated by measuring certified reference materials and by comparing the results of ED-XRF and INAA for four elements. Fresh samples of coal, bottom ash and fly ash have been obtained from about 35 thermal power stations in the country and their analysis is being taken up. The fly ash samples are also to be sieved into four size ranges and analysed. The samples are also to be measured for their natural radioactivity by gamma-ray spectrometry. It is also proposed to do ED-XRF studies on the fly ash samples and leaching tests are to be carried-out. 10 refs, 4 tabs

[en] The sampling and analysis of air particulates and rainwater for fallout radioactivity in the late 1950s and 1960s have provided substantial experience in carrying out trace element measurements on environmental samples from many cities in the country. The common factors have been sampling methods and gamma/X ray spectrometry. Regular procedures in use over the last 30 years have shown that harmonization of environmental data can be achieved by following tested procedures with good analytical practices. Regular quality assurance procedures have allowed investigations, through trace element determinations, of a number of varied topics ranging from health related applications and long range transport of aerosols to cloud physics and geochemical studies. For trace element measurements instrumental neutron activation analysis (INAA) and energy dispersive X ray fluorescence (EDXRF) methods have been used. Generally, fewer problems have been encountered with INAA where the results are fairly precise as compared with EDXRF, where more care is required in the analysis. Some errors that creep in with EDXRF could be attributed to pellet preparation and interference connections. Some topics to which these two analytical techniques have been applied at the Bhabha Atomic Research Centre are discussed in the paper. (author)

No abstract available

[en] The reactor accident at Chernobyl caused environmental monitoring programmes to be organised on an emergency basis in several countries. The accident drew attention to the inadequacies of the current monitoring programmes and the need for renewed research in certain areas of radiation protection. The impact of this accident on the monitoring programmes with special reference to India is discussed in this paper. The differences between Chernobyl and nuclear weapons test fallout, the new problems that were posed including the constraints on the resources are described. The paper includes a discussion on the future strategies for radiation monitoring. (author). 30 refs

[en] The trace element concentrations in sediments have been used as indicators for the History of metal pollution in many areas as the sediment is considered to be major sink for chemical components of the water bodies. Such studies are useful to estimate the impact of a particular industrial activity on water and also provide guidelines for planned development. Remote regions where pollution and impact of industrialization is Negligible are considered as representative of pristine environment. Crescent shaped Nainital lake which is a tectonically formed sub-tropical and eutrophic lake situated at an Altitude of about 1937 meters above mean sea level (latitude 29o24'n and Longitude 79o23'e) in Nainital district of Kumaun Himalayas was considered as study area. The Average depth of lake is 18.5m spread over an area of 4,65,000m2 with a maximum depth Of 27.3m. The catchment area of lake is 4.9km2. The concentration and distribution of the Toxic and trace elements As, Ba, Br, Co, Cr, Cs, Fe, Ga, K, Mn, Na, Rb, Sc, Sr, Th and Zn were investigated in dated sediment cores of Nainital lake which is considered as a Remote background area. The concentration of elements in the core section was measured By Instrumental Neutron Activation Analysis using K*0 method. Its main advantage is the Combination of high sensitivity and accuracy of the results. The lake sediment standard S L-3 of IAEA was used as the standard. The normalized data for a series of elements Were used to understand the source of loading. The elements like Br, Co, Cr, Fe, K, Mn And Zn show a negative correlation with depth, whereas elements like As, Ba, Cs, Na and Rb show a positive correlation. Assuming the concentration for the bottom segments as Close to the base line concentration, recent flux for different elements was calculated. An Increase in the flux value was observed in the case of Br, Cr, Fe, K, Mn and Zn, which Can be attributed to anthropogenic contribution in the recent years

[en] The results of analysis of coal, bottom ash, ESP ash and fly ash from stacks obtained from some thermal power stations in India are presented and discussed. Some elements in the fly ash collected from stack tended to show an enrichment over the electrostatic precipitator (ESP) ash. The natural radioactivity in these samples were also measured by gamma spectrometry. The size distribution of fly ash samples were studied. By using available software an idea of the magnitude of deposition of various elements released from stacks were obtained for a typical Indian city. The Polish candidate fly ash and air filter samples for intercomparison were also analyzed. (author). 11 refs, 4 tabs

[en] A simple equation relating the intensity of characteristic X-ray lines to their respective weight fractions has been obtained for a thick sample excited by an isotopic source. It follows from the equation that a single intense line in a standard sample suffices to generate calibration constants over a wide range of elements. Validity of this approach has been demonstrated by the analysis of a standard soil sample using only the Fe Kα line for calibration. A procedure for correction of peak overlaps has been given using the Kβ/Kα ratios, modified by the matrix effects. The method is very useful for the analysis of soil samples and can be conveniently applied to other matrices. (author)