Pakistan has huge deposits of 185 billion tons of lignite coal deposits. The major deposits are found in lower Indus Basin, southern Sindh. The coal basins extend westward from Thar coal field, near Islamkot through Badin to Lakhra-Sonda and Meting-Jhimpir-Thatta area. There are 16 coal samples from southern coalfields of Pakistan have been analyzed for the presence of mercury. The results show that the mercury in Thar coal samples varies from 0.38 to 0.56 ppm, with an arithmetic mean of 0.45ppm. In Lakhra coals, the concentration varies from 1.12 to 1.94 ppm with an arithmetic mean 1.34 ppm Whereas, in Meting-Jhimpir coal samples, it varies from 1.748 to 1.750 ppm with arithmetic mean 1.75 ppm. The current results indicate that the mercury in Thar coal has originated as silicate bound, in Lakhra coals as sulfide bound, and in Meting-Jhimpir coal, as carbonate bound. Calculated enrichment/depletion factor shows that the mercury in Thar and Lakhra coal samples is significantly enriched, whereas in Meting-Jhimpir coal it is very highly enriched. The comparison of present data with world average values shows that the average mercury contents in coal samples of Thar coalfield relative to Lakhra and Meting-Jhimpir coalfield are very near to the world average and is of silicate bound nature. Therefore, it will pose no environmental threat if proposed coal-fired power station is installed, to overcome the energy crises of Pakistan
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