The concentration level of hydrogen sulphide acid in the sediment contaminated by mining activities can be applied as criteria ability of sediments to bind the heavy metals and mobility of such metals. The determination of hydrogen sulphide acid (HSA) by molecular absorption spectrometry and combustion-IR analysis in sediment samples is described. The liberation of H2S is performed through the addition of the concentrated sulphuric or hydrochloric acid. The liberated hydrogen sulphide is measured directly using molecular absorption spectrometry (MAS) and by absorbing the HSA in a silver nitrate solution and measuring the precipitated sulphur by combustion (the IR method). The lowest determinable concentrations were at the level of 2–10 mg g–1.