1. Comparison of Environmental Impacts of Wood Treated with Three Different Arsenic-Free Preservatives and CCA CCA-TAG Meeting B. Dubey 1, T. Townsend 1, H. Solo-Gabriele 2 1 University of Florida, Dept. of Environ. Eng. Sciences 2 University of Miami, Dept. of Civil, Arch. And Environ Engineering August 18, 2005

2. Research Objective Compare and contrast the potential environmental impact of wood treated with arsenic and chromium free preservatives with that from CCA-treated wood

3. Specific Objectives 1.Leachate characterization for heavy metals in the leachate produced on co- disposal of pressure-treated wood in C&D and MSW landfill environment 2.Impact of surface water conditions on chemical leaching and aquatic toxicity of pressure-treated wood 3.Impact on soil from pressure- treated wood leachates

4. Pressure Treated Wood Being Evaluated ACQ : Alkaline Copper QuaternaryACQ : Alkaline Copper Quaternary CBA : Copper Boron AzoleCBA : Copper Boron Azole DOT : Disodium Octaborate TetrahydrateDOT : Disodium Octaborate Tetrahydrate CCA : Chromated Copper ArsenateCCA : Chromated Copper Arsenate

5. Leachate characterization for heavy metals in the leachate produced on co- disposal of pressure-treated wood in C&D and MSW environment -Simulated C&D landfill environment -Leaching with MSW leachate Disposal Scenarios

6. The county provided a large area near a paved road for locating the lysimeters.

7. The driller used a 3-ft bucket auger.

8. The hole prior to lysimeter installation. 15 ft deep.

14. The annulus of the holes was backfilled with sand.

15. Thermocouple wires were included for temperature measurement.

16. Waste Composition for Simulated C&D Landfill

17. Waste Composition for Co-disposal of ACQ in Simulated C&D Landfill

18. Waste Composition for Co-disposal of CCA in Simulated C&D Landfill

19. Cutting wood into smaller pieces

20. ACQLead based paintCCA

21. Loading the Column

23. C&D Lysimeters

24. C&D LBP, CCA, Hg lamps Wood blocks added during mixing Wood blocks throughout lysimeter Hg lamps were broken inside lysimeter, starting after first lift LBP, CCA River Rock LBP, CCA Hg lamps

25. C&D LBP, ACQ, Hg lamps Same as C&D lysimeter with CCA wood, but ACQ treated wood used instead. LBP, ACQ River Rock LBP, ACQ Hg lamps

26. Compacting the Waste

28. Water addition

29. Filling sampling bottles

35. Copper was below detect in all three C&D column leachates throughout the duration of experiment

36. Batch Test Results Blocks of CCA and ACQ were leached in leachates from the control columns. The results were compared to results from leaching blocks using the TCLP and SPLP.

37. As Cu Cr Leaching of CCA Blocks

38. Leaching of ACQ Blocks Copper Boron

39. Minimal leaching of copper observed suggesting that disposal of copper-based wood preservatives posses minimal impact to groundwater from copper leaching What will happen if the landfill gets aerobic over a long period??

40. Leaching of treated wood sawdust with MSW landfill leachate Sawdust samples of CCA, ACQ, CBA and Borate treated wood was prepared from treated wood lumber 26 MSW landfill leachate samples were collected to use as the leaching fluid Batch leaching test of TCLP, SPLP and WET was also conducted for comparison

41. X mg/L

46. Summary of results for MSW leaching study Metals leach from pressure treated wood when leached with landfill leachate Leaching concentrations from the pressure treated wood vary with leachate quality Results indicate that the co-disposal of treated wood with municipal solid waste could impact the leachate quality

47. Impact of surface water conditions on chemical leaching and aquatic toxicity of pressure-treated wood

48. Parameters being measured Total copper, free copper and toxicity analysis using MetPlate and Algal assay will be performed on each wood block leachateTotal copper, free copper and toxicity analysis using MetPlate and Algal assay will be performed on each wood block leachate Samples will also be analyzed for TOC, TDS, alkalinity and anionsSamples will also be analyzed for TOC, TDS, alkalinity and anions

49. Some preliminary leaching data

50. Impact on soil from pressure- treated wood leachates

51. Decks have been set up at Solar Energy Research Park, UF

52. Soil column in lab with three soils

53. Parameters being analyzed Preservative components, pH, ORP, Conductivity in leachate and soil Soil samples being characterized for pH, OM, CEC, Grain size distribution etc.

54. In summary Out of 4 experiments comparing the treated wood, two have been completed and two are underway Results from uncompleted experiments will be updated in the subsequent meetings

55. Questions?