Authors: Sujit Kumar, Dr. Sanjay Kumar Singh, Dr. Niranjan Kumar Mandal
Abstract: Coal mining can influence riverine water quality through runoff, sediment transport, and the movement of dissolved constituents. This comparative study examines seasonal water-quality patterns reported in two related investigations of the Ajay River system: one covering two canals and the other covering three barrages. Both studies considered the rainy, winter, and summer seasons and reported physicochemical parameters, selected metals, chemical oxygen demand (COD), biochemical oxygen demand (BOD), dissolved oxygen (DO), and total coliform counts. The canal results showed rainy-season turbidity of 20 NTU in both canals, while winter turbidity differed sharply between Canal 1 (0 NTU) and Canal 2 (25 NTU). In the barrage study, turbidity ranged from 17–20 NTU during the rainy season, fell to 0 NTU in winter, and rose to 22–35 NTU in summer. The barrage sites also showed higher summer COD (8–13 mg/L), BOD (3–4 mg/L), and coliform counts (2.3–2.7 × 102 CFU/100 mL) than in the rainy season. Across both studies, reported concentrations of most measured metals were low or below the stated detection limits, although iron varied in the barrage samples. The comparison indicates that seasonal conditions and the type of water body may shape the observed water-quality profile. However, the studies do not provide sufficient site-level information or statistical analyses to establish that coal mining alone caused the observed differences. Consistent sampling, clearly documented analytical methods, and expanded metal and microbial monitoring are recommended.
DOI: https://doi.org/10.5281/zenodo.23417929
