Chemical and microbial sulphuric acid production from aerated mine lake sediment that was treated by different additions of NaOH (speech)

We examined sediment from an open pit lake that was intensively used for coal mining during the first decade of 20th. century. Today, the site (Lake 111, Lusatia, Germany) is flooded and water has extreme chemistry: low pH values (2-3), high concentrations of sulphate (up to 2000 mg/l) and elevated concentrations of Fe, Zn and Mn. As a result, anoxic sediment accumulated elevated concentrations of these elements, especially high levels of reduced sulphur compounds. (orig.)