System and method for treating contaminated wastewater

A process for treating contaminated mining wastewater, comprising:

• flowing the contaminated mining wastewater into at least one initial filter bed comprising a layer of gravel on top of a layer comprising a mixture of sand and zero-valent iron;
• flowing the contaminated mining wastewater from the at least one initial filter bed into at least one pre-pond solids filter tank comprising sand;
• flowing the contaminated mining wastewater from the at least one pre-pond solids filter tank into at least one sedimentation pond;
• flowing the contaminated mining wastewater from the at least one sedimentation pond into at least one filter tank comprising at least one layer of sand and at least one layer of a mixture of sand and zero-valent iron;
• and
• discharging treated mining wastewater from the at least one filter tank;
• wherein the treated wastewater upon discharge has less than 10 parts per billion arsenic, less than 65 parts per billion iron, and less than 5 parts per billion suspended solids.