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The research was employed to simulate the watershed's hydrologic behavior and to predict stream flow in the Mahan River catchment area alongside the effect of six underground (UG) and opencast (OC) mines for the past decades. Following the SWAT model run, the mining area sub-watersheds possess (SW20, SW26, SW28, SW31 and SW38) a comparatively lesser sediment yield of 61.41 Metric Ton/ha than that of non-mining area sub-watersheds 159.40 Metric Ton/ha. Amongst all hydrological components, evapotranspiration with 531.2 mm consumed 39% of the total annual precipitation (1365.3 mm). The total discharge was estimated to be 775.57 mm, which comprises Surface Runoff of about 351.89 mm, Return Flow (402.21 mm) and Lateral flow (21.47 mm), while percolation into the unconfined and confined aquifers as soil and groundwater storage also accounted for 58.86 mm. The statistical indicators and graphs indicate that the model performs satisfactorily for the daily streamflow (R2 = 0.875, p = 0.71, r = 0.76 and NSE = 0.87 during the validation (R2 = 0.817) as that during the calibration period. The model performed satisfactorily during the simulation and the results showed that the mines play a critical role in changing the hydrological regime of the watershed with low recharge and moderate evapotranspiration characteristics. Taken together, the SWAT model appears to be a reliable tool for forecasting stream discharge over long periods of time, in parallel with the likely impacts of mining activity on HRUs. [ABSTRACT FROM AUTHOR]

Groundwater water inrush into mines from aquifers underlying coal seams is often disastrous. Multiple factors control the groundwater inrush processes. For coal seams #10 and #11, ten main controlling factors were determined and quantified separately. The thematic map of every controlling factor was obtained with the data processing functions of GIS after the data were normalized. The influence weight of each factor was calculated using the AHP vulnerability index method. Superimposition of thematic maps with the GIS results in the vulnerability zoning map for coal seams #10 and #11. The appropriate prevention and control measures against the groundwater inrush are then proposed according to the vulnerability zoning map. [ABSTRACT FROM AUTHOR]

Preliminary results of ambient indoor/outdoor gamma dose rates measured for Muzaffarabad city, the state capital of Azad Kashmir, are presented. Measurements of indoor/outdoor environmental exposures were carried out using a portable Ludlum Model 19 Micrometer. Effect of altitude on measured values of gamma dose rates has also been investigated. Besides measuring the gamma dose rates for indoor and open environment, measurements have also been taken within two coal mines. Effects of lithology on gamma dose rates have also been investigated. For outdoor measurements, minimum and maximum gamma dose rates were found as 533 ± 4.33 and 1,143 ± 2.96 μGy y, while for indoor environment minimum and maximum gamma dose rate value were found as 533 ± 4.33 and 979 ± 3.2 μGy y. Average values of indoor and outdoor gamma dose rates were found as 761 ± 3.62 and 710 ± 3.75 μGy y. Gamma dose rates have also been calculated with altitude variations. Measured values of gamma dose rates show a weak positive correlation with altitude. For measurements made in coal mines, maximum gamma doses rate value was found as 3,490 ± 1.69 μGy y, situated at a height of 1,098 m, located at Sangri Mera. Results obtained from the current study show that annual effective doses from gamma radiation exposure does not pose health threat to the population of district Muzaffarabad. [ABSTRACT FROM AUTHOR]