OBJECTIVE To assess whether the recent increases in the prevalence of coal workers' pneumoconiosis (CWP) in the USA reflect increased measured exposures over recent decades, and to identify other potential causative factors. METHODS The observed CWP prevalence was calculated for 12,408 underground coal miner participants in the Coal Workers' Health Surveillance Program for the period 2005-200...

Fieldwork during the 1988 season involved investigation of the thermal affects of tectonic movement on vitrinite reflectance near the Quintette Coal Limited mining operation in northeastern British Columbia. Two samples, collected in 1987, from the same seam on either side of a fault, suggested a significant rank increase associated with the stmctwe. These sites were revisited and sampled toget...

This paper reports the mineralogical compositions of super-low-sulfur (Yueliangtian 6-upper (YLT6U)) and high-sulfur (Yueliangtian 6-lower (YLT6L)) coals of the Late Permian No. 6 coal seam from the Yueliangtian coal mine, Guizhou, southwestern China. The mineral assemblages and morphology were detected and observed by X-ray diffractogram (XRD), optical microscopy and field-emission scanning el...

Real time interrogation and analysis of coal makes it possible to quickly respond to changing conditions and efficiently control coal quality closely to meet operational or contractual specifications. Real time measurement systems generally include an online analyzer, an integrated mechanical sampling system for calibration of the analyzer and for collecting shipment or daily contract samples, ...

The key to the safe mining of thick coal seams under rivers is understanding the development patterns of fractured water-conducting zones (FWCZ) when various mining methods are used. To solve this problem, we employed numerical simulation to investigate FWCZ when slice mining and longwall caving mining are performed. When slice mining was carried out, the maximum height of the FWCZ in the highe...

As more easily mined deposits are depleted, the reserves are becoming more limited and less favorable. Deposits of coal or trona that are being longwall mined are deep and are getting deeper. Coal bursts and bumps frequently occur within development entries in longwall mining of deep mines due to high stresses. This paper presents a novel patented longwall mining layout “Longwall Mining with Sp...

PT.X, a coal mining company in South Kalimantan, Indonesia, plans to use the highwall method excavate marginal reserves on final slope maintain production. However, stability of and determination dimensions are major concerns due unfavourable rock mass conditions caused by intensive weathering tectonics. This paper aims evaluate feasibility study area using empirical, analytical numerical metho...

The distribution of Selenium (Se) in the Jurassic-Cretaceous Mist Mountain Formation of southeastern British Columbia was documented in a previous study by Ryan and Dittrick (2001). As part of that study, complete sections of rock types, including coal seams were sampled, as well as various materials segregated by mining such as coarse refuse and solid tailings from tailings ponds. Preliminary ...

Many coal seams contain coalbed methane (CBM) yet most of the world’s production comes from the San Juan Basin in the United States. In fact CBM production from this basin of about 0.9 tcf/yr accounts for about 80% of the CBM production in the US (1.2 tcf/yr) and about 60% of world production. Success in the San Juan Basin is not because of increased gas content in the coals compared to coals i...