1	An Investigation of Recycled/Industrial Materials to Attenuate Hydrogen Sulfide Resulting from the Use of C&D Debris Fines
2	Use of C&D Debris Fines Recycling Construction and Demolition (C&D) debris (part of RCC) Products: concrete, asphalt, brick, metal, wood, fines/residuals Historically fines used as landfill daily cover and shaping and grading material Hydrogen sulfide emissions linked to wallboard Recycling still encouraged MA Landfill bans of unprocessed materials (concrete, asphalt, brick, wood and metal) Unless processing changes significantly (do remove wallboard), solutions include attenuation materials and other uses
3	Hydrogen Sulfide
4	Recycled/Industrial Materials for Attenuation Large resource/high availability Lower cost Attenuation characteristics Sorption or chemical reactions High percentage of carbon, lime or iron Able to be mixed-in/used in layers Investigations in Florida and New England indicated that various recycled/industrial materials can attenuate hydrogen sulfide
5	Hypothesis and Objectives Hypothesis: One or more of the materials outlined in the literature could be economically utilized as an amendment for C&D debris fines to attenuate the production of hydrogen sulfide in-situ Objectives: to further the goals of C&D debris recycling by maximizing the safe and economical use of C&D debris fines to better understand the mechanisms of hydrogen sulfide generation to evaluate the most efficient and economical attenuation and removal measures.
6	Local Stakeholders/Partners WMMA UNH Dept. of Resource Economics Green Seal Environmental (CMRA) MA DEP
7	Experimental Design Attenuation characterization of various materials Characterization of C&D debris fines Sorting Percent gypsum¹ Mix-in materials in bench scale setting ¹Protocol developed at the University of Florida by T. Townsend
8	Materials Tested Complete Soil Weathered Cement Kiln Dust (CKD) Wood Ash In-Process Coal Fly Ash Taconite (mine tailings) Unweathered CKD
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18	"Tests performed weekly" Tests performed weekly H₂S concentration pH Conductivity Oxidation Reduction Potential Dissolved Oxygen Sulfate (Ion Chromatograph) Sulfide (Hach Spectrophotometer)
19	Mean Leachate Values (Preliminary Data)
20	Gas Production WMMA Samples, 5%, 10% wood ash producing relatively regularly Other fines and 20% wood ash produced small amount 1:1, 2:1, 3:1 Soils:Fines and simulated fines not emitting appreciable amounts
21	Real Samples
22	Fines with Wood Ash
23	Fines with Soil
24	Comparisons
25	Summary – Preliminary Data Attenuation materials behave differently ex-situ and in-situ Of materials tested so far, wood ash best for ex-situ attenuation Other materials still to be tested Soil appears to be best for in-situ attenuation of concentration and volume of hydrogen sulfide Dilution 2:1 or 3:1 (soil : fines) Wood ash at 20% or greater – some in-situ attenuation Other materials could be tested If recycling requirements exist, there must be markets for the products. If recycled/industrial materials available and found to attenuate in-situ, may be able to use them at less percentages than soil, maximizing use of C&D fines
26	Acknowledgements Waste Management of MA (WMMA) UNH Students Olivier Dalbavie (France) Ashlee Fuller (UNH) Kelly Bryan (UNH)
27	Thank You Contact information: Jenna Jambeck University of New Hampshire Jenna.Jambeck@unh.edu 603-862-4023