Abstract: Blockage often occurs in heap leaching, causing a continuous change in porosity and making the seepage coefficient no longer constant.In view of this, mechanical block was modeled with acid leaching of mixed ores and chemical block with bacterial leaching of sulfide ore.The seepage velocity and pressure of each leaching column were monitored periodically and the regression analysis was conducted on the regularity of seepage coefficient's change with leaching duration by Markov software.The results indicate that chemical blockage can have a greater impact on the seepage than mechanical block.

Key words: Heap leaching, Seepage coefficient, Mechanical block, Chemical blo