A probabilistic predictive method for estimating the risk of acid mine drainage generation within the copper tailings dump of the Sarcheshmeh copper mine, Iran, has been presented in this paper. For this purpose, the input and output parameters were determined after gathering historical data and building an appropriate database. Some of the critical parameters, including depth, and concentrations of bicarbonate, chloride, nitrate, and nitric, were considered input data, while the output parameters were chalcopyrite, pH. The best distribution functions on each input parameter were found by Chi Sq. criteria. Subsequently, the best linear statistical relationships between the input and output data were determined. Then, the best probability distribution functions of output parameters were defined by inserting the input parameters in the obtained linear statistical relationship. The results showed that the remaining chalcopyrite fraction values were between 0.1094 % and 0.2159% at a 90% probability level. In contrast, the pH values would be expected between 3.13 and 8.04 at this probability level.