Initial Success in Design and Modeling of a Landfill Cover using Salix on the Solvay Waste Beds in Syracuse, NY Presented at the Third International Phytotechnologies Conference April 20-22, 2005 Atlanta, GA D. Daley1, T. Volk2, A. Johnson1, J. Mirck2, L. Abrahamson2 Faculty of Environmental Resources and Forest Engineering 2 Faculty of Forest and Natural Resources Management State University of New York, College of Environmental Science and Forestry, Syracuse, NY 13210 www.esf.edu 1 Presentation Outline Site history Project goal and objectives Vegetation selection and management Model selection and calibration Summary Site History Soda ash manufacturing using the Solvay process (1887 – 1986) Raw materials locally available Solvay Process Company Facility and Erie Canal, early 1900s limestone, brine (NaCl) and water 1907 – Solvay began operation of settling basins along Onondaga Lake Process residues discharged as a slurry (5% solids) Site Location On on da ga La ke Syracuse, NY o o N 43 04’ 26” W 076 14’ 58” Solvay Process Residues Waste Beds 9 to 15 15 to 21 m deep 270 ha (662 acres) Primarily a non-hazardous mixture of calcium, magnesium and sodium compounds Stressful growing conditions in shallow soil (<1m depth) pH (8.0 – 12.3) Electrical conductivity (0.5 – 9.2 dS/m) Organic matter (0 - 3.9%) Waste Beds 13 - 15 Project Goal and Objectives • Determine the feasibility of using willow shrubs as part of a multipurpose landfill closure project. • • • Screen varieties suitable for wastebed environment. Evaluate transpiration by willow shrubs. Model the effect of evapotranspiration on leachate generation. • • Evaluate the feasibility of large-scale willow biomass crop production on the waste beds. Determine the value of the willow biomass crops for green fuel, bioproducts and recreation. Willow Biomass Crop Management Challenges Water: Select willow varieties that are productive on this site Promote evaporation and transpiration to decrease deep percolation (leachate generation) Soils: Vegetation interception Low water use efficiency Planting density and design Understory vegetation management Overcome harsh growing conditions Incorporate organic matter to : Enhance survival, growth and productivity Improve soil water availability and capacity Provide long-term beneficial use option for generators of biosolids and organic mulch Vegetation Selection Why willow? Naturally established willow and poplar on the Solvay waste beds. one of the first woody species to establish naturally tolerant of harsh conditions high transpiration rates high growth rates genetic diversity Greenhouse Screening Trials Greenhouse screening trial of 40 willow and hybrid poplar varieties. Screened 40 varieties of willow and hybrid poplar from SUNY-ESF collection Used biosolids amended waste, unamended waste and a control Used aboveground and belowground growth results to select 10 varieties to test in field trials Growth and Yield Trials Two plots (2004) First-year growth of willow on biosolids-amended Solvay waste biosolids-amended (1986) unamended waste Two cutting lengths (25 and 50 cm) Planting density 15,000/ha (6,000/ac) First-year Survival of Willow on Biosolids-amended Solvay Waste 120 25 cm 50 cm Survival (%) 100 80.1% survival on unamended waste (Field 2) 80 60 40 20 0 9 - 6 6 3 7 -7 7 7 0 - 2 3 7 1 - 2 6 7 1 - 3 1 S 3 6 5 S V 1 S X 6 1 S X 6 4 1 0 81 98 98 98 98 Salix varieties First Year Growth of Willow on Biosolids-amended Solvay Waste 100 80 2 Basal area (cm /plot) 25 cm 50 cm 60 40 20 0 5 1 1 4 1 6 3 7 6 01-69837-79870-29871-29871-3 S 36 SV SX 6 SX 6 1 8 9 Salix varieties Average basal area on Field 2 (unamended waste) (1.2 cm2/plot) Conceptual Hydrologic Model PPT = (E + T) + RO + ∆S + D Provided by Honeywell and O’Brien & Gere Conceptual Heat and Water Model for a Willow Biomass Crop Climate Crop Management PPT = 1,018 mm annually PPT = 560 mm (Nov – Apr) o Average temp. = 8.3 C 3-year harvest rotation Soil modifications with organic amendments & tillage Determine effect on percolation (leachate generation) (Figure supplied by USDA) The Simultaneous Heat and Water (SHAW) Model One-dimensional model developed to simulate soil freezing and thawing. Simulates snow accumulation and snowmelt, transpiration and actual evaporation. Incorporates biomass and other crop management practices as input parameters. Model Calibration Using Sap Flow Stem heat balance method Three-year old willow on mineral soil Sensor sizes range from 10 - 35mm Measure: sap flow (g/hr/stem) and stem diameter distribution (stem/ha) Compute: Stand-scale sap flow (l/day) 6/2 9/1 0 04 9/2 9/2 0 04 2/2 9/2 0 04 5/2 9/2 0 04 8/2 10 0 04 /1 / 2 10 0 04 /4 / 2 10 0 04 /7 / 10 20 0 /1 0 4 1 0 /2 0 0 /1 3 4 1 0 /2 0 0 /1 6 4 1 0 /2 0 0 /1 9 4 1 0 /2 0 0 /2 2 4 1 0 /2 0 0 /2 5 4 / 10 2 00 /2 8 4 1 0 /2 0 0 /3 1 4 /2 11 004 /3 / 2 11 0 04 /6 / 2 11 0 04 /9 / 11 20 0 /1 2 4 1 1 /2 0 0 /1 5 4 /2 0 04 9/1 S a p fl o w (l / d a y ) Stem Size Differences in Late Season Sap Flow for One Variety 4 SX64, 16mm sap flow l/day 3.5 3 SX64, 25mm sap flow l/day SX64, 35mm sap flow l/day 2.5 2 1.5 1 0.5 0 Time (day) Stem Diameter Distribution to Determine Stand-level Sap Flow 20000 S25 SV1 SX64 18000 14000 12000 10000 8000 6000 4000 2000 >4 0 37 _4 0 34 _3 7 31 _3 4 28 _3 1 25 _2 8 22 _2 5 19 _2 2 16 _1 9 13 _1 6 10 _ 13 0 <1 0 Number of stems ha-1 16000 Diameter class (mm) Sensor sizes (16, 25, 35 mm) Projected Late Season Sap Flow Salix Variety Sap Flow (l/d/plant) S25 Sap Flow (mm) 180 SV1 65 1.2 SX64 131 2.5 October 8 – November 15, 2004 3.4 Summary Willow (Salix) can be successfully established when organic amendments are incorporated into wastebeds Late season transpiration by willow is important to the water balance Growth rates and transpiration rates vary amongst willow varieties Early modeling indicate that Salix minimizes deep percolation Future Activities - 2005 Monitor key soil and vegetation characteristics on the waste beds Begin trials on the waste beds with different organic amendments Quantify sap flow over entire growing season Complete initial model runs and identify key variables Calibrate and verify model output Acknowledgements Honeywell International O’Brien & Gere Companies Selection of Salix for Field Trials Selection criteria: Greenhouse screening trial of 40 willow and hybrid poplar clones. Survival Below-ground biomass (consider root : shoot ratio) High water use “efficiency” (e.g. high water use : biomass ratio)