Journeys on a Limping Mule What We Know About Bioreactors

One who knows and knows that he knows... His horse of wisdom will reach the skies. One who knows, but doesn't know that he knows... He is fast asleep, so you should wake him up! One who doesn't know, but knows that he doesn't know... His limping mule will eventually get him home. One who doesn't know and doesn't know that he doesn't know... He will be eternally lost in his hopeless oblivion! Ibn Yamin Faryumadi ( )

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Why Bioreactors ?  Proven technology  Requires no modification of current practices  No land taken out of production  No decrease in drainage effectiveness  Very low maintenance  Estimated life - 10 to 15 years  Cost effective

Concentration of Nitrate-N (mg/L) Hydraulic Retention Time (mins) Corncob Mix data points Wood mix data points Corncob Mix fitted line Wood Mix fitted line CD=68% Removal Efficacy is a Function of Oxygen Saturation, Carbon Source and Retention Time

Hydraulic retention time (mins) 20c20c 50c50c 10 0 c 15 0 c 20 0 c 25 0 c Measured Points (2 o C) % Nitrate Remaining Concentration of Nitrate-N (mg/L) Removal Efficacy is a Function of Temperature

First Generation Bioreactors

Capacity Control Structure 5’ Soil Backfill Woodchips Trench bottom 1’ Below tile invert Section of perforated tile Length/width dependent on contributing area Diversion Structure Second Generation Bioreactors

Capacity control structure 5’ section of non-perforated tile Diversion structure Top View 5’ Soil backfill

Combination structure 5’ Soil backfill Non-perforated tile Perforated tile

60 minutes after injection 120 minutes after injection

Dissolved MeHg in Bioreactor Inlets -Eight non-detects -Six samples contained detectable MeHg - Maximum: 0.16 ng/L - Maximum: 0.16 ng/L - Average:0.09 ng/L - Average:0.09 ng/L

Dissolved MeHg in Bioreactor Outlets

Capacity Control Structure 5’ Soil Backfill Woodchips Trench bottom at the tile invert level Length/width dependent on contributing area Diversion Structure Third Generation Bioreactors Section of perforated tile

No nitrous oxide was released from the system

Phosphorus Removal Chamber Solid pipe Perforated pipe Plastic Liner

Site Drainage Area (acres) Bioreactor Area (square feet) Loading Density (acres/100 sq. feet) Decatur West De Land West Amenia Decatur East Bloomington North De Land North De Land East Mount Zion

Chipometer

Thank You! Richard Cooke Department of Agricultural and Biological Engineering University of Illinois