Using C&D Fines and Residuals to Close Landfills Lessons Learned. James Doucett Business Compliance Division Bureau of Waste Prevention MassDEP

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1 Using C&D Fines and Residuals to Close Landfills Lessons Learned James Doucett Business Compliance Division Bureau of Waste Prevention MassDEP 1

2 Overview Background how did we arrive at allowing use of C&D residuals in landfills Problems that developed Solutions Looking forward 2

3 Key Issues for Massachusetts: Lack of landfill capacity Goal to maximize diversion of C&D waste from landfilling Number of old landfills never properly capped and closed 3

4 Since 2000 Master Plan: Banned disposal of specific C&D materials in 2006 Conducted case studies to promote C&D source reduction Provided over $700,000 in grants and loans to develop C&D related recycling infrastructure Developing new end-use markets for processed C&D and wood in particular Allowed C&D residuals to be used to close inactive LFs 4

5 Response by Industry In late 1990s, in response to the proposal to ban disposal of C&D waste, the C&D processing industry took off 5

6 Response by Industry Before 2000 Master Plan: 6 C&D processing facilities Currently: 11 operating C&D processing facilities 2 in permitting 2 others located in NH on Mass border Over 3 million tpy of processing capacity, which more than takes care of Mass C&D waste 6

7 Snapshot of C&D Processing ,160,000 tons C&D generated 4,500,000 tons diverted/recycled 3,470,000 tons - ABC materials 100,000 tons - Metal 30,000 tons - C&D wood recycled 50,000 tons - C&D wood for boiler fuel 50,000 tons - Woodwaste (clean wood) 20,000 tons - Other (ceiling tiles, carpet, gypsum wallboard, and asphalt roofing shingles) 810,000 tons - C&D fines and residuals for closures 7

8 Life is Good, Right? 8

9 Problems in Processor Paradise C&D materials can be difficult to recover and recycle Weak markets (C&D wood, for example) Wood biomass facilities located in Maine Controversy on burning C&D wood What do you do with residuals and fines? Expensive to dispose of residuals and fines ($60-$100/ton) 9

10 Industry Response Temporary closure of processors - Nov no place to send residuals Proposed using residuals to close old landfills! 10

11 DEP Response Unlined Landfill Closure Policy: Allows use of materials for grading and shaping old landfills prior to capping C&D fines and residuals Coal ash Contaminated soils that meet MassDEP soils policy Dredge spoils, street sweepings, etc. Provides guidance on permitting process Establishes standards for materials and projects to promote consistency 11

12 Why Use C&D Fines and Residuals to Close LFs? 700+ old MSW landfills in Massachusetts Lots of pre-1971 landfills never capped and closed properly or only with minimal soil cover 1971 regulations had minimal closure standards 1990 regulations require up-to-date closures Have closed over 150 LFs since

13 Why Use Fines and Residuals? Development pressures land is valuable, even old LFs Municipalities own most of those old landfills Cost of closure is high no money set aside to close large burden on tax rate 13

14 Why Use Fines and Residuals? Fines and residuals can be used to grade the landfill substituting for higher cost soils Town can charge a tipping fee for the materials Set aside $$ for assessment, closure, capping and post-closure monitoring and maintenance 14

15 Why Use Fines and Residuals? The Big Issues: What volume of grading and shaping material is really needed? To simply close the LF it is X To set aside enough money to also pay for the capping and closure it is X+Y To maximize profits it is X+Y+Z How much time is needed to grade then cap the landfill? 15

16 Major Goals of Policy Promote a permanent, permitted C&D recycling/processing infrastructure Maximize recycling of C&D materials Ensure there is a home for C&D residuals Level Playing Field all landfill closures play by same rules 16

17 The Process 17

18 Stage 1 Consolidation and Pre-shredding 18

19 Stage 2 Mechanical Separation/Screening 19

20 Stage 4 Duel-line Picking Stations 20

21 Stage 5 Float Tank/Density Separation 21

22 Stage 6 Residual & Fuel Production 22

23 C&D Residuals in Use 23

24 C&D Residuals in Use 24

25 C&D Residuals in Use 25

26 C&D Residuals in Use 26

27 Problems H 2 S gas generated that resulted in odor problems Why? theories Concentrations 27

28 What Caused Odor Problem? H 2 S issue much worse than expected Possible Causes: Grinding wallboard increases surface area for reaction Large amount of material going into LF over short period of time Conditions were ripe: Anaerobic conditions Moisture 28

29 How Bad Can it Be? Raw LF gas from gas probes: MSW landfill not using residuals or fines H 2 S <100 ppm Landfill using residuals and fines H 2 S>20,000 30,000 ppm 29

30 Where Did We Get into Trouble? Happened quickly anaerobic conditions, moisture and short period of time (9 months to 1 year) No financial assurance to cover H 2 S pretreatment and flaring LF gas Pretreatment is expensive Pretreatment technology not fool-proof 30

31 Solutions Source separation of wallboard at job sites Front-end removal of wallboard by C&D processors Mix soils with residuals Install gas collection, pre-treatment and flaring systems as closure progresses 31

32 What Has MassDEP Done? Require operator to address site-specific problems when they arose Cover what s there Stop taking more residuals until under control Install gas collection and pre-treatment New or revised policies Demonstration project 32

33 C&D Residuals in Use 33

34 C&D Residuals in Use 34

35 What Has MassDEP Done? Site specific solutions Gas pre-treatment to knock down H 2 S Gas treatment flares Reduce or eliminate use of fines and residuals Require higher ratio of soil to fines and residuals, at least 3:1 recommended Apply final cap as soon as possible in phases if necessary 35

36 What Has MassDEP Done? Pre-treatment Issues: 2 basic systems: Sulfa-treat low capital cost, high operating cost Scrubbing high capital cost, low operating cost Systems not designed for high concentrations of H 2 S - must change out media often - $$$$ If concentration of H 2 S at inlet to flare is too high, flare will exceed permitted SO 2 conc. Supplemental fuel needed, not enough methane 36

37 What Has MassDEP Done? Policies Modify Unlined Landfill Closure Policy to include Addendum with BMPs Developed H 2 S Policy to address odors 37

38 Best Management Practices Addendum to Closure Policy Setbacks to residences for future projects Wallboard separation program required Monitor sulfate content in residuals and fines Require minimum 3:1 ratio of soil to residuals Develop odor control plan (H 2 S Policy) Financial assurance for gas treatment 38

39 H 2 S Policy Requires Odor Control Plan be developed by landfills using C&D residuals and fines Establishes Action Levels: Odor Action Level H 2 S Action Level 15 ppb over 8 hr; or 30 ppb over 1 hr. Progressive series of steps if problems develop 39

40 H 2 S Policy Steps: Log complaints Determine nature, extent and severity of odor problem Implement corrective actions (stop using residuals, apply soil daily cover, etc.) Implement 24 hr. monitoring if not a specific source using soil probes/wells and near-surface 40

41 H 2 S Policy Steps (continued): Implement off-site gas monitoring if necessary Install gas collection, pre-treatment and flare Implement community communication plan Conduct additional off-site monitoring at receptor locations 41

42 Demonstration Project Marion LF Demonstration Project Project Requirements Gypsum removal Concentrations of sulfate measured before and after gypsum removal program Mix ratio of soils with fines and residuals Limited to residuals from only one C&D processor Monitored H 2 S generation 42

43 Gypsum Wallboard Removal Plan To create a low gypsum/sulfate product at New Bedford Waste Services, they Educated customers that gypsum wallboard is a problem Surcharged clients who delivered co-mingled gypsum wallboard Bypassed all visual wallboard from the C&D processing line Hand sorted clean gypsum wallboard for recycling Created fines and residuals with a lower sulfate content 43

44 Clean Gypsum Wallboard Recycling (covered container) 44

45 NBWS In-house Sulfate Levels Data (pre-gypsum removal) Material Fines/Residuals Date 11/8/2005 Concentration 57,000 mg/kg Fines/Residuals 11/9/ ,000 mg/kg Fines/Residuals 11/10/ ,000 mg/kg Fines/Residuals 11/11/ ,000 mg/kg 45

46 NBWS In-house Sulfate Levels Data (post-gypsum removal) Material Fines/Residuals Date 1/16/2006 Concentration 4,900 mg/kg Fines/Residuals 1/17/2006 6,600 mg/kg Fines/Residuals 1/18/2006 7,200 mg/kg Fines/Residuals 1/19/2006 4,800 mg/kg 46

47 Marion LF Results to Date Odors have not developed No need for LF gas pre-treatment or flaring so far Monitoring Data: 15 soil gas probes inserted 12 feet into the LF H 2 S measured in the LF soil ranged from 0.0 ppm to 48.0 ppm (1 sample) H 2 S measured at the LF surface at ppm or 1 ppb 47

48 Looking Forward Managing C&D has been interesting: Processors stepped up to the plate and built facilities Markets for reuse/recycling/diversion still an issue Still believe residuals and fines can be successfully used, but must apply BMPs Management of residuals key if processors are to remain a part of our C&D management infrastructure 48

49 Looking Forward Work To Do: Reduce the amount of residuals and fines generated Firm up markets for C&D wood Expand wallboard recycling Recycle ceiling tiles and carpets Ensure use of residuals and fines will not cause problems in future Continually push for source separation to achieve better products 49

50 Looking Forward Ze-Gen Pilot Project gasification of C&D wood Clean Wood BUD Biomass Projects Will facilities burning C&D wood get Renewable Energy Credits (RECs)? Wallboard recycling Clean wallboard scraps currently recycled Old wallboard 50

51 Need More Information? James Doucett MassDEP website 51