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Distribution of sulfur and its three predominant forms in 10 lignitic coal seams developed in fluvial environments in east Texas was examined. The average sulfur content for individual seams varied from 0.88 to 3.98%, while the total sulfur content of 10‐cm sections of these seams varied from 0.53 to 16.79%. Sulfate sulfur was a minor component compared to pyritic or organic sulfur. The organic sulfur content determined by the standard American Society for Testing and Materials (ASTM) procedure as the difference between the inorganic sulfur (sulfate + pyritic sulfur) and the total sulfur in the original material, in general, remained uniform within a given lignite profile. A significant correlation was obtained between the organic sulfur content obtained by the ASTM procedure and a more direct method of density separation of specific gravity < 1.6 fraction and the determination of total sulfur in this fraction with an induction furnace and automatic titrator. Pyritic sulfur had the most variable distribution with a greater concentration of pyrite occurring at the seam fringes, which suggests the need for separate handling of these highpyrite content mine spoils for safe disposal.

Major tasks in this NRC sponsored program include(1) an evaluation of the acceptability of low-level solidified wastes with respect to minimizing radionuclide releases after burial, and (2) an assessment of the influence of pertinent environmental stresses on the performance of high-integrity radwaste container (HIC) materials. The waste form performance task involves studies on small-scale laboratory specimens to predict and extrapolate: (1) leachability for extended time periods; (2) leach behavior of full-size forms; (3) performance of waste forms under realistic leaching conditions; and (4) leachability of solidified reactor wastes. The resultsshow that leach data derived from testing of small-scale specimens can be extrapolated to estimate leachability of a full-scale specimen and that radionuclide release data derived from testing of simulants can be employed to predict the release behavior of reactor wastes. Leaching under partially saturated conditions exhibits lower releases of radionuclides than those observed under the conventional IAEA-type or ANS 16.1 leach tests.The HIC assessment task includes the characterization of mechanical properties of Marl ex CL-100, a candidate radwaste high density polyethylene material. Tensile strength and creep rupture tests have been carried out to determine the influence of specific waste constituents as well as gamma irradiation on material performance. Emphasis in ongoing tests is being placed on studying creep rupture while the specimens are in contact with a variety of chemicals including radiolytic by-products of irradiated resin wastes.

Abstract. This paper focuses on the spatio-temporal trends of precipitation over the Ganga Basin in India for over 2 10 centuries. Trends in precipitation amounts are detected using observed data for historical period in 20th century and using downscaled precipitation data from 37 GCMs for 21st century. The ranking of 37 GCMs (from CMIP5 archive) is done employing a statistics based skill score. The best ranked GCM output is then bias corrected with observed precipitation prior to further analysis. The direction and magnitude of trend in annual and seasonal precipitation series is determined using Mann Kendall's test statistic (ZMK) and Thiel Sen's Slope estimator (β). The plots depicting the spatial variation of ZMK 15 and β are prepared which provides a comprehensive inter-scenario comparison of spatio-temporal trends in precipitation series. Highly non-uniform spatio-temporal trends are detected for observed precipitation series. It is observed that the precipitation for annual and southwest monsoon season is indicating a rising trend for all future emission scenarios in the region adjacent to Himalayas (northeast side of study area) but shows falling trends in the plains away from the Himalayas.Insignificant trends are observed in pre-monsoon and winter season precipitation. An inter-emission-scenario comparison 20shows that for higher emission scenarios the annual and southwest monsoon precipitation is showing rising trends with increasing spatial dominance i.e. the area under rising trends increases as we observe it from low to high emission scenarios.