Therefore, four factors are generally considered to mainly govern the chemical process that leads to the precipitation of calcium carbonate: calcium concentration, concentration of dissolved inorganic carbon (DIC), the pH value and availability of nucleation sites (Hammes and Verstraete, 2002). Many bacterial species have earlier been identified and suspected to be connected with natural carbonate precipitates from different environments. The main function of the bacteria in the precipitation process has consequently been attributed to their capability of creating an alkaline environment through the increase in pH value and dissolved inorganic carbon during their physiological activities (Hammes and Verstraete, 2002).