Welcome to ITRC’s Internet-Based Training: “Constructed Treatment Wetlands”

1. Welcome to ITRC’s Internet-Based Training:“Constructed Treatment Wetlands” Thank you for joining us. Today’s training focuses on the ITRC Technical and Regulatory Guidance Document entitled: “ Technical & Regulatory Guidance for Constructed Treatment Wetlands ” The training is sponsored by: ITRC & EPA Office of Superfund Remediation and Technology Innovation Creating Tools & Strategies to Reduce Technical & Regulatory Barriers for the Deployment of Innovative Environmental Technologies

2. ITRC Member State ITRC (www.itrcweb.org) – Shaping the Future of Regulatory Acceptance Host Organization • Network • State regulators • Federal government • Industry • Consultants • Academia • Community stakeholders • Documents • Technical and regulatory guidance documents • Technology overviews • Case studies • Training • Internet-based • Classroom ITRC State Members Federal Partners DOE DOD EPA

3. Alternative Landfill Covers Constructed Treatment Wetlands Environmental Management at Operational Outdoor Small Arms Ranges DNAPL Performance Assessment Mitigation Wetlands Perchlorate Overview Permeable Reactive Barriers: Lessons Learn and New Direction Radiation Risk Assessment Radiation Site Cleanup Remediation Process Optimization Site Investigation and Remediation for Munitions Response Projects Triad Approach What’s New With In Situ Chemical Oxidation Characterization, Design, Construction and Monitoring of Bioreactor Landfills Direct-Push Wells for Long-term Monitoring Ending Post Closure Care at Landfills Planning and Promoting of Ecological Re-use of Remediated Sites Rads Real-time Data Collection Remediation Process Optimization Advanced Training More in development……. ITRC – Course Topics Planned for 2006 Popular from 2005 New in 2006 Training dates/details at: www.itrcweb.org Training archives at: http://cluin.org/live/archive.cfm

4. Presentation Overview What are Constructed Wetlands Mechanisms of treatment when using constructed wetlands Various applications for treating surface water using Constructed Wetlands Contaminants most commonly treated using constructed wetlands Important design consideration when considering using Constructed wetlands Limitations Regulatory Issues Key questions you should ask Logistical Reminders Phone Audience Keep phone on mute * 6 to mute your phone and * 7 to un-mute Do NOT put call on hold Simulcast Audience Use at top of each slide to submit questions Course Time = 2 ¼ hours 2 Question & Answer Periods Links to Additional Resources Your Feedback Constructed Treatment Wetlands

5. Meet the ITRC Instructors Paul Eger Minnesota Department of Natural Resources 500 Lafayette Road, Box 45 St Paul, MN 55155 Phone: 651-296-9549 Fax: 651-296-5939 paul.eger@dnr.state.mn.us Arati Kolhatkar Atlantic Richfield Company (a BP affiliate) 501 Westlake Blvd, Suite 20.104B, Houston, TX 77079 Phone: 281-366-5596 Fax: 281-366-7094 arati.kolhatkar@bp.com Charles Harman AMEC Earth & Environmental, Inc 285 Davidson Ave, Suite 100 Somerset, NJ 08873 Phone: 732-302-9500 ext. 127 Fax: 732-302-9504 charles.harman@amec.com

6. What are Constructed Treatment Wetlands? • Man made • Built specifically to remove contaminants in waters that flow through them • Wide variety of removal processes • Generally not designed to fully recreate the structure & function of natural wetlands • See ITRC Guidance Document: Characterization, Design, Construction, and Monitoring of Mitigation Wetlands (WTLND-2, 2005)

7. Background • Wetlands have been used to treat wastewater in US for several decades • Primarily municipal and stormwater • Application of technology expanding to new areas • Newer designs based on a more thorough understanding of science and underlying mechanisms

8. Why Wetlands? • Wetlands may offer a lower cost, lower maintenance alternative to standard chemical treatment • Classic example of passive treatment • Passive treatment systems use natural processes to remove contaminants • Designed to be low maintenance • A “perfect” passive system would operate indefinitely with no maintenance

9. Key questions to ask • Is a wetland appropriate for this situation? • Is this the right design? • Is the wetland big enough to handle changes over time? • How long will it continue to provide treatment? • Will it be necessary to dispose of the substrate in the wetland? • Will it produce consistent compliance? • Are there any potential ecological impacts?

10. Applications • Stormwater Runoff • Municipal Waste Treatment • Mine Drainage • Industrial Waste Treatment • Remedial Wastewater Treatment • Effluent from Landfills • Agricultural • On-site Wastewater

11. What We Need to Know Before Constructing Treatment Wetlands • Fundamental mechanisms of wetlands function • Characteristics of the water being treated • Chemistry • Flow • Site characteristics (Climate and Topography) • Removal rates • Regulatory Limits

12. Mechanisms • Abiotic • Settling & sedimentation • Sorption • Chemical Oxidation & Reduction-precipitation • Photo oxidation • Volatilization • Biotic • Aerobic or anaerobic Biodegradation/ Biotransformation • Phytoaccumulation • Phytostabilization • Rhizodegradation • Phytodegradation • Phytovolatilization

13. Photo-Oxidation CO2 Mechanisms Phytovolatilization Emergent Aquatic Macrophyte Floating Aquatic Macrophyte Submergent Aquatic Macrophyte Inlet Outlet Particulate BOD removal Denitrification Filtration Biodegradation FlocculantSettling TSS removal Nitrification Rhizodegradation Precipitation Hydrogen Sulfide available Anaerobic decomposition Discrete Settling Detritus buildup – peat development

14. Hg, Se Volatilization Sedimentation Adsorption & Stabilization Abiotic Mechanisms Treating Inorganic Compounds Suspended Inorganic = Red Circles Emergent Vegetation Free Water Layer Flow Direction Settling / Precipitation Litter Layer Sediment Layer

15. Photo-Oxidation CO2 Volatilization Settling Adsorption & Stabilization (Biodegradation) Sedimentation Abiotic Mechanisms Treating Organic Compounds Suspended Organic = Red Circles Emergent Vegetation Free Water Layer Flow Direction Litter Layer 4 Sediment Layer

16. Suspended Inorganic = Red Circles Phytovolatilization (Blue Lines) Emergent Vegetation Hg, Se Clarified Effluent Flow Direction Litter Layer Phytostabilization Biotic Mechanisms Treating Inorganic Compounds Free Water Layer Sediment Layer

17. Phytovolatilization Clarified Effluent Phytodegradation Rhizodegradation Phytostabilization Biotic Mechanisms Treating Organic Compounds Emergent Vegetation Suspended Organic Free Water Layer Flow Direction Litter Layer Sediment Layer

18. Primary Contaminant Removal Mechanisms (See Table 2-1)

19. Aluminum (AL) • Oxidation and hydrolysis Arsenic (As) • Formation of insoluble sulfides; Binding to iron and manganese oxides Cadmium (Cd) • Formation of insoluble sulfides; Filtration of solids and colloids Chromium (Cr) • Reduction to non-mobile form by bacterial activity Copper (Cu) • Sorption onto organic matter; Formation of insoluble sulfides; Binding to iron and manganese oxides; Reduction to non-mobile form by bacterial activity Iron (Fe) • Oxidation/hydrolysis; Formation of carbonates or sulfides; Binding to iron/manganese oxides Lead (Pb) • Formation of insoluble sulfides; Filtration of solids and colloids; Binding to iron and manganese oxides Manganese (Mn) • Oxidation and hydrolysis; Formation of carbonates; Binding to iron and manganese oxides; Nickel (Ni) • Sorption onto organic matter; Formation of carbonates; Binding to iron and manganese oxides Selenium (Se) • Reduction to non-mobile form by bacterial activity Silver (Ag) • Form insoluble sulfides; Filtration of solids and colloids Zinc (Zn) • Formation of insoluble sulfides; Filtration of solids and colloids; Binding to iron and manganese oxides Removal Mechanisms for Metals (See Table 2-2)

20. Types of Systems • Surface Flow (SF) • Subsurface Flow (SSF) • Riparian Buffer

21. Surface Flow Wetlands (SF) • Water flow occurs above the substrate • Preferred choice for treatment of contaminants that are predominantly removed by aerobic processes Advantages Simple design Less costly as compared to Subsurface systems

22. Surface Flow Wetland Outflow Inflow Outflow Inflow Effluent Effluent Wetland Control Control Wetland Control Control Collection Collection Plants Structure Structure Plants Structure Structure System System 2”-12” Flow Influent Influent To Pond or To Pond or Distribution Distribution Receiving Receiving System System System System Organic Organic Liner Substrate Substrate

23. Subsurface Flow • Water flows below ground surface through the substrate • Two types of systems based on hydraulics: • Horizontal • Vertical • Also known as • Rock Reed filters , Reed beds, Gravel beds, Vegetated submerged beds, or Root zone method

24. Subsurface Flow Wetland Advantages • Higher treatment efficiencies as compared to surface flow systems • More surface area for biofilm development • Reduced risk of public exposure, odors, or insect vectors • Greater thermal protection due to subsurface flow of water • Increased accessibility for maintenance

25. Subsurface Flow Wetland Inflow Control Structures Outflow Control Structures Influent Planting Substrate Water Level Hydraulic Influent Influent Gradient Distribution Distribution To Receiving To Receiving System System System System Effluent Effluent Treatment Media Treatment Media Collection System Collection System (gravel, sand, soil) Liner (gravel, sand, soil)

26. Typical Configurations of Constructed Wetlands “ 1. 1. 4. 4. 2. 2. LinearCells 3.

27. Choice of Wetland Type • Treatment goals • Mechanisms involved • Maintenance Issues • Air Emissions/Ecotoxicity Concerns • Area availability • Cost

28. Riparian Buffer

29. Applications • Stormwater Runoff • Municipal Waste Treatment • Mine Drainage • Industrial Waste Treatment • Remedial Wastewater Treatment • Effluent from Landfills • Agricultural • On-site Wastewater

30. Stormwater Control • Primary function: reduce suspended solids Generally contains low levels of contaminants Reduce peak discharge of infrequent large storm events Photo here Greenwood Park, Orlando, Florida

31. Stormwater “Typical Constituents and Concentrations”

32. Constructed Stormwater Wetland • Generally surface flow • Low levels of contaminants

33. Typical Surface Flow Wetland Design

34. Stormwater Wetland Removal Efficiencies %

35. Municipal Wastewater Wetland Treatment • Used in 34 states to treat municipal wastewater • Typically as a polishing step • Now considered effective as a secondary treatment Tres Rios constructed wetlands, Arizona

36. Typical Characteristics of Municipal Wastewater (EPA 2000)

37. Municipal Wastewater Characteristics and Removal Efficiencies, Tertiary Treatment (Data is from Kadlec and Knight 1996)

38. Mine Drainage Water in contact with rock containing reactive minerals Primarily iron sulfides Nearly 12,000 miles of rivers and streams & 180,000 acres of lakes and reservoirs affected in the US Mine waste stockpiles

39. Mine Drainage • Net Acid: Acidity> Alkalinity • Generally pH < 6 (Excess acidity) • Net acidic water require subsurface wetlands • Net Alkaline:Acidity< Alkalinity • pH > 6 (Excess Alkalinity) • Net Alkaline waters can be treated using Surface or Subsurface wetlands • Design information in guidance document Mine drainage wetland, northern Minnesota

40. Characteristics of Mine Drainage Except for pH all concentrations are in mg/L

41. Typical Range of Removal in Wetlands Constructed to Treat Mine Drainage

42. Industrial Waste Water Wetlands Treatment • Petrochemical Facilities • Refineries • Pulp and paper processing • Tanneries • Food Processing • Department of Defense Facilities • Deicing • Explosive residue Chevron Wetland

43. Industrial Wastewater • Highly variable between sites • Function of type of industry process • Relatively constant at given site • Function of specific industrial • Flow • Water quality • May require pretreatment Dupont Victoria wetland, Texas

44. Treatment Efficiency, Industrial Wastewaters (Petrochemical)

45. Remedial Activities • Contaminated groundwater • Landfills

46. Remedial Wastewater • Site specific • Typical contaminants • VOC’s • BOD, COD • PAH’s • metals

47. Hazardous Waste Landfill, Concentrations and Removal Efficiency

48. Municipal and Sanitary Landfill Leachate • Leachate composition is related to • type of waste • landfill age • Other factors affecting leachate quality • variability in landfill design • annual precipitation • evapotranspiration • groundwater flow

49. Landfill Leachate CharacteristicsNote: Data from NCEL, 1991

50. Municipal and Sanitary Landfill Leachate Wetland treatment system Fort Edward, NY landfill