RESUMO
The present article deals with soil analysis around five opencast coal projects of Ib river coalfield during pre-monsoon (March), monsoon (July) and post monsoon (November) periods of successive three years (i.e., 2006, 2007 and 2008). Sampling of soil has been done from the vertical surface of the overburden at successive depths of 0-5 ft, 5-10 ft and at 10-15 ft. The different physical (soil texture, soil moisture, particle density, bulk density and porosity) and chemical (pH, organic carbon, nitrogen, phosphorus and potassium) parameters have been analysed. The soil textures of the study area are found to be loamy sand to loam, loam to silty loam and clay loam to silty clay loam in the depth of 0-5 ft, 5-10 ft and at 10-15 ft, respectively. The moisture content (7.297 at 0-5ft, 5.25 at 5-10 ft and 4.134% at 10-15 ft) and porosity (43.994 at 0-5ft, 40.682 at 5-10 ft and 35.85% at 10-15 ft) of the soil in the study area decreased gradually from the surface to greater depth. However, the particle density (2.639 at 0-5ft, 3.11 at 5-10 ft and 3.523 g cc-1 at 10-15 ft) and the bulk density (1.478 at 0-5ft, 1.839 at 5-10 ft and 2.269 g cc-1 at 10-15 ft) in this region increased from surface to the deeper region of the soil. The organic carbon (1.367 at 0-5ft, 0.9 at 5-10 ft and 0.396 kg ha-1 at 10-15 ft), nitrogen (2.845 at 0-5ft, 1.059 at 5-10 ft and 0.48 kg ha-1 at 10-15 ft) and phosphorus level (1.11 at 0-5ft, 0.715 at 5-10 ft and 0.679 kg ha-1 at 10-15 ft) of the soil decreased with increasing depth of the soil. However, the content of potassium (2.636 at 0-5ft, 4.374 at 5-10 ft and 5.82 kg ha-1 at 10-15 ft) increased gradually from the surface to the greater depth. Analysis of variance is computed to infer the variation in the concentration of parameters in different opencast coal projects and in various depths of the study area.
RESUMO
The miners as well as the inhabitants vicinity to the mining areas are generally susceptible to the respiratory disorders due to constant exposure to the coalmine dust for a prolonged period. In this paper, the dust concentration and dust dose associated with the rate of tuberculosis around the major part of Ib Valley Coalfield (Belpahar and Brajarajnagar area) have been analysed. Several field trips around Ib Valley Coalfield have been conducted for consecutively three years (2005, 2006 and 2007) to evaluate the present status of the dust concentration and rate of tuberculosis infection. It was observed that the dust concentrations of different residential places as well as the places vicinity to the opencast mining projects have been increased in the subsequent years of investigation. As a result, the dust doses of various residential places have also increased in a parallel manner. The dust doses of various mining sites range from 25.51 to 37.08 mg, 34.76 to 41.03 mg and 37.8 to 44.49 mg during 2005, 2006 and 2007 respectively. Interestingly, in most of the mining sites the dust doses are more than the safe dust does (32 mg). An attempt has been made to correlate the dust concentration with tuberculosis infection in the area by making a questionnaire survey. Early symptoms of tuberculosis were reported in case of 121 out of 205, 129 out of 212 and 145 out of 220 inhabitants during 2005, 2006 and 2007 respectively. The study clearly revealed that the tuberculosis patients have been increased significantly in the successive years of investigation.