1. R. S. Govindaraju, J. E. Alleman, T. J. Cooper, T. P. Chan, V. Jain School of Civil Engineering Purdue University (SPR-2455, SPR-2456, SPR-2487) I-70 Greenfield Rest Area Constructed Wetland Wastewater Treatment System Research Project March 19, 2004

2. June 11, 20152 Project location

3. June 11, 20153 ST-2ST-1 W-1 W-2 W-3 Biofiel d F-2 AS-3 AS-2 AS-1 AS-4 F-3 F-1 M-1 M-2 LS-2 LS-1 LS-3 LS-4 M-3 M-4 Effluent Inflow Septic tank Automatic sampler V-notch weir Lift station / dosing chamberMagnetic flow meter Wetland cell Recirculation North Rest Stop South Rest Stop Design layout

4. June 11, 20154 Hydraulic issues Undersized wetland dosing pumps (LS-1)  Surges from the eastbound side  High rate of recirculation (~83%) Solutions  Reduce recirculation rate  Addition of surge tank

5. June 11, 20155 Flow measurements Weir / flume measurements are NOT accurate  Backup due to overcapacity of LS-1 and LS-4  Inadequate calibration  Inherent error due to low flows Magnetic flow meters  More reliable  Erroneous spikes in the data

6. June 11, 20156 02/0102/0802/1502/22 0 1000 2000 3000 4000 5000 6000 Date Daily Flow Total (gal) Inflow (M-1) Outflow (M-4) Flume 1 Flume 2 Flume 3

7. June 11, 20157 9/25/2003

8. June 11, 20158 02/0102/0802/1502/2202/2903/07 0 2000 4000 6000 8000 10000 12000 Date Daily Flow Total (gal) Inflow (M-1) Outflow (M-4) Biofield (M-3) 02/0102/0802/1502/2202/2903/07 150 200 250 300 350 400 450 Daily Streamflow (cfs) Big Blue River

9. June 11, 20159 Wastewater test results 12/22/2003 SamplepH TSS (mg/L) NH 3 -N (mg/L) BOD 5 (mg/L) Sampler #18.8011083280 Sampler #38.246062225 Sampler #48.176065215

10. June 11, 201510 Wastewater test results 3/5/2004 SamplepH TSS (mg/L) NH 3 -N (mg/L) BOD 5 (mg/L) Sampler #18.40140136310 Sampler #27.94110122294 Sampler #37.7260131310 Sampler #47.656080226

11. June 11, 201511 Current status Only receiving wastewater from west-bound side No recirculation Flow-through with no drain-and-fill Biofield shut down till desired effluent quality is attained

12. June 11, 201512 To-do list Installation of SCADA system Surge tank addition Installation of weather station Re-calibration of weir and flume meters