1. Treatment Wetlands Presented by: Scott Wallace, P.E.
(612)

2. References for Wetland Design
Water Environment Research Foundation (WERF)
Small Scale Constructed Wetland Systems (Wallace & Knight, 2006)
Treatment Wetlands 2nd Edition
(Kadlec & Wallace, 2009)

3. Types of Treatment Wetlands
Surface Flow (SF)
Horizontal Subsurface Flow (HSSF)
Vertical Flow (VF)
Sludge Dewatering Reed Beds
Intensified Wetlands
Aerated (cold climates)
fill-and-drain (warm climates)
reactive media (ammonia, phosphorus, etc)
industrial wastewaters

4. Surface Flow Wetlands
Kadlec & Wallace, 2008

5. Champion Paper, Pensacola Florida
Surface Flow Wetlands
Champion Paper, Pensacola Florida

6. Horizontal Subsurface Flow Wetlands
Wallace & Knight, 2006

7. Horizontal Subsurface Flow Wetland
Wildflower Meadows: 90-person treatment system

8. Vertical Flow Wetland
IWA, 2000

9. Vertical Flow Wetland
Rousillon, France

10. Sludge Dewatering Reed Bed
Skovby, Denmark: 8000-person treatment wetland
Kadlec & Wallace, 2008

11. Main Treatment Mechanisms
Adsorption of dissolved-phase hydrocarbons
Microbial degradation of organic compounds
Settling of particulate compounds
Oxidation and reduction of nitrogen compounds
Precipitation of metals
Use of intensification methods (aeration and reactive medias to accelerate treatment)

12. Natural vs. Mechanical Systems
LEAST
Energy and O&M Needs
MOST
Mechanical Treatment Systems
Intensified Wetlands
Natural Systems
MOST
Area Requirements
LEAST

13. Climate Range of Treatment Wetlands
Wellsville, New York
Northern Sahara,
Libya

14. Casper, Wyoming
Casper

15. BP – Casper, Wyoming Refinery
Operated 1912 to 1991
37,000 m3 of LNAPL recovered to date
Extensive smear zone due to river flooding
50 to 100 years to remediate site
High mountain west: -35oC

16. BP – Casper Wyoming Refinery

17. Casper Reuse Plan
HSSF Wetlands
SF Wetlands

18. Full-Size System from Pilot Data
Wallace & Kadlec, 2005

19. Casper Intensified Wetland Cell

20. Casper System Construction

21. Casper Wetland Construction

23. Casper Benzene Data 2004 - 2006 Benzene effluent at Outfall 001
consistently below detection levels
<0.01 mg/L

24. Rosebel Gold Mine
Project Site

25. Cyanide Removal

26. Iron Removal

27. Multi-Stage Treatment Processes
Wetlands are typically multi-stage treatment systems
Process Chemistry
Site Topography
Compania Minera Antamina, Peru

28. Conclusions
Treatment wetlands are already being used in North America, South America, Europe, Asia and Australia
Surface flow, horizontal subsurface flow, vertical flow, and intensified wetlands are all being used
Use of wetlands for treatment wetlands is increasing on two major fronts:
Range of applications in different industries
Construction of wetlands in different geographic regions

29. Treatment Wetlands
Thank you for your time