Lead speciation in the technogenesis zone of coal mining sites (case of Vizeyska mine of Chervonohrad mining area, Lviv region, Ukraine)

Abstract

Total forms and "mobile" fractions of lead in dump rocks and adjacent territories of the impact zone of the Vizeyska mine of the Lviv-Volyn coal basin have been investigated. Environmental hazard caused by distribution of various forms of lead is analyzed basing on establishment of regularities of lead distribution in technogenesis zone. The concentration of lead in total form and acid-soluble, acetateammonium and water-soluble extracts have been detected in argillites, siltstones, sandstones, coal from waste heaps, as well as in the soil at a distance of 50 m and 200 m from the foot of the heap. The content of total forms of lead in the waste heaps ranges from 4.72 mg/kg to 16.97 mg/kg. The concentration of lead in the acid-soluble extract is the highest in unburned coal - 3.39 mg/kg, the lowest in unburned siltstone 1.88 mg/kg. The reduction of lead content in ammonium acetate extract is somewhat different - from 1.5 mg/kg in unburned siltstone and burnt siltstone to 0.99 mg/kg in burnt sandstone. The lead content in the aqueous extract ranges from 1.25 mg/kg in unburned coal to 0.48 mg/kg in unburned argillite. The coefficients of lead concentration in the samples were determined by relation to the total form. The coefficients of lead concentration in the rocks species were determined by relation to the clarke. Due to the results of the research the waste heap rocks of the Vizeyska mine can be regarded as safe for the environment and suitable for use in terms of the distribution of various forms of lead in rocks and soils.