A method of compacting solids in situ in an oil sands extraction tailings pond. The method includes the steps of placing two or more electrodes into the tailings pond in a predetermined spacing and connecting the electrodes to a source of power, having a variable voltage. This creates at least one cathode and at least one anode and an electrical field therebetween. The electrical field is of a sufficient strength to induce flocculation of particles in the tailings and to simultaneously release water. Then the solids undergo further compaction with further water release to create a solid material having a minimum desired load bearing capacity. In a further embodiment an electrode used in carrying out the method is provided.