GSA Connects 2021 in Portland, Oregon

Paper No. 216-8
Presentation Time: 10:15 AM


FINKELMAN, Robert, University of Texas at Dallas Department of Geosciences, 800 W Campbell Rd, Richardson, TX 75080-3021

Uncontrolled coal fires are known to have occurred in prehistoric times and, more recently with the proliferation of coal mining and use, in dozens of countries around the world. The fires can be caused by spontaneous combustion, mining accidents, and intentionally. Regardless of how they start the fires are notoriously difficult to extinguish and destroy millions of tons of coal annually while polluting the environment. Despite their wide geographic distribution, proximity to population centers, and sometimes displays of spectacular blazing fires, there have been relatively few investigations on their health impacts. This despite the fact that it has long been demonstrated that these fires mobilize such potentially toxic elements such as arsenic, mercury, selenium, fluorine as well as a range of deadly gases. Recent studies have shown that villagers in the Jharia region of India living about one mile from an active uncontrolled fire had 95% greater incidence of self-reported health issues than villagers living five miles away from the fires. In the same region at an active underground coal fire, samples of coal, condensates around vents, soil, water, and plants were collected and analyzed for their fluorine contents. Characterization of condensates revealed an abundance of fluorine-bearing minerals. Fluorine in coals is generally around 100 ppm but the fluorine in the coal samples collected from the region had about 450 ppm. The condensates from one site averaged about 70,000 ppm F with one sample having 38 wt. % F! The plants in that region had as much as 7,000 ppm F in the leaves while the soil samples had more than 300 ppm F and the water samples had about 140 ppm F: all exceptionally high concentrations. SEM/XRD analysis of the condensates revealed abundant crystals of bararite and cryptohalite, both ammonium fluorosilicates as well as a series of iodine minerals, many containing fluorine. The ultimate source of the fluorine may be fluor-apatites in the coal. The possible health impacts of these exceptionally high concentrations of fluorine should be investigated.