Removal of selenium from coal mining runoff water

A system for removing selenium from surface runoff water from reclaimed land in a coal mining operation where overburden has rock containing selenium, comprising:

• at least one detention pond receiving such surface runoff, the detention pond being effective to settle out particulate and suspended matter from the runoff water,
• a treatment plant for removing selenium from the runoff water, with a pump delivering runoff from the detention pond to the treatment plant,
• the treatment plant including a prefilter for removing particulate material from the runoff water, a means for adjusting pH of the runoff water as necessary to place the acidity of the runoff water in a range of about pH 5.0 to pH 7.0, and a reactor column downstream of the pH adjustment means and receiving the runoff water, the reactor column comprising a vessel containing a contact bed of SMI for contact with the runoff water, and a pump for passing the runoff water through the reactor column in an upflow direction, the reactor column being effective to remove a significant portion of selenium contained in the runoff water to produce a treated water.