This document summarizes a teach-in on composting strategies for Palo Alto held on January 10, 2009. It introduced the organics challenge facing Palo Alto and discussed various technology options for composting, including windrow composting, aerated static pile composting, in-vessel composting, and anaerobic digestion of food waste. It also covered experiences with composting in the Bay Area, biochar technology, and the impact of various approaches on global warming. Participants were provided information but the event did not attempt to determine locations or solve the problem.

1. A Compost Teach-In: Informing Palo Alto’s Future Organics Strategy Lucie Stern Community Center January 10, 2009 2 PM to 4:30 PM

2. Where This Teach-In Fits Update Task Force? Council

3. Agenda Welcome – 2:00 PM Introduction --- 2:05 PM Framing the Organics Challenge 2:10 PM Technology Options 2:30 PM Composting Windrow Aerobic Static Pile In-vessel Anaerobic Digestion of Food Waste -- 3:00 PM Bay Area Composting Experiences -- 3:20 Biochar Technology -- 3:40 PM Where Does Global Warming Fit -- 4:00 PM Technologies Transportation Discussion -- 4:15 PM

4. Today’s Approach What Is “Taught” The Problem Some Technologies Global Warming Considerations What Is Avoided Not Discussing Locations Not Attempting to Solve the Problem A Facilitator’s Role Mind the Clock Moderate Discourse Record Comments 20 Minutes Per Topic 15 Minutes Presenting 5 Minutes Questions Logistics Bathrooms + Breaks Web Cast

5. Brought to You by… Teachers Hilary Gans Ann Schneider, Sierra Club Sophia Skoda, EBMUD Steven Sherman, Steven Sherman Consulting Bob Niederman Bob Wenzlau, Terradex Bryan Long David Coale Facilitator and Recorder (Palo Alto Mediation Program) Elaine El-Bizri Elisabeth Seaman Support Jeb Eddy Susan Stansbury

6. THE CHALLENGE Bob Wenzlau, Terradex

7. Take Care With The Compost Gods

8. Each Year Palo Alto’s Organics Will Fill A Football Field The Height of City Hall 130,000 Cubic Yards

9. Three Sources of Organics 60,000 Tons Per Year Composition of Disposed Organics

10. Disposed Waste: Where Organics Fit?

11. Biosolids Generation Source: http://www.cityofpaloalto.org/civica/filebank/blobdload.asp?BlobID=3740 Wastewater Sludge Incineration 17,117 metric tons of CO2e per year.

12. Current Organics End Points

13. TECHNOLOGY Hilary Gans Ann Schneider Sophia Skoda, EBMUD Steven Sherman, Steven Sherman Consulting Bob Niederman

14. Technology Questions What is it? Reference URLs to learn more Example Sites of Use Land Requirement Who Makes it? Land Use Requirement (receiving, processing, product storage) Economics (Capital, Operation, Revenue) Environmental Impact (Energy Use, GHG, bi-products, noise or odors) Lead time

15. TECHNOLOGY: COMPOSTING Hilary Gans Ann Schneider

16. Recycling It all started with AB939

17. Can’t get there without recycling organics Recyclables combined = 40% Organics alone equal almost the total tonnage of recyclables CIWMB 2004 waste charactorization study

18. Residential Yard Trimmings Collection

21. Newby Island Composting Facility

22. Z-Best Composting Facility

23. Windrow Yard Trimmings Composting

24. Aerated Static Pile Composting Technology

27. The building is an all-metal construction in a seismic zone 4 for a high snow-load

28. The facility is designed to process 45 tons/day of mixed organic waste. All process functions (pre-processing, composting, curing and product refining) are conducted within this building.

30. Finish Product Screening

31. Finished Product . . . Compost 1/2 inch screen size Maturity – 7 index C:N ratio 17 Dark brown and musty 309 lbs/cyd Organic (about 50% O:InO) Contamination: Bits-O-plastic

32. Compost Marketing

33. Compost to the Community

34. Turf Application ALLIED WASTE

35. Composting operations are difficult to site because Neighborhood opposition Cost of locating near cities is high There is little political will to site facilities Real potential for odor problems Cost of permitting and environmental clearance for new site development

38. Questions

39. TECHNOLOGY: ANAEROBIC DIGESTION Sophia Skoda, EBMUD

58. TECHNOLOGY: BAY AREA COMPOSTING EXPERIENCE Steven Sherman, Steven Sherman Consulting

59. Nearby Bay Area Communities with Food Scraps Collection and Composting San Francisco: all residents; available to all businesses (over 3,000 participants) Alameda County: all residents; available to most businesses (over 500 participants) San Mateo County: coming in 2011 for all residents; available to most businesses (over 500 participants) Santa Clara County: Will Palo Alto take the lead?

60. Schematic of Possible Materials Flow Residential yard trimmings PLUS food scraps  windrow or aerated static pile  compost, mulch (lowest cost, most replicated technology) Clean, source-separated commercial food scraps  anaerobic digestion  bio-gas + compost feedstock for non-restricted use (low to moderate cost) Bio-solids  anaerobic digestion, ideally kept separate from food scraps  bio-gas + compost feedstock for restricted uses (moderate cost) Organic residue still in trash after waste reduction, recycling, and composting  anaerobic digestion or other conversion technologies prior to final disposal

61. Technology Operating Cost Ranges ($ per ton) Windrowing $20-$50 Aerated Static Pile $25-$55 In-vessel System $35-$65 Anaerobic Digestion $35-$90

62. TECHNOLOGY: BIOCHAR Bob Neiderman

69. GREENHOUSE GAS IMPACTS Bryan Long David Coale

70. Does Composting Contribute to Global Warming?

71. Composting vs. What?

72. Water-Wise Landscaping? Reduction is good! Back yard composting is good! Still have lots of organic material.

73. Landfill? More expensive than composting. Methane leakage

74. Incineration? Expensive Full release of organic carbon as CO2 CO2 emissions from additional fuel required

75. The question is not WHETHER we are going to compost or convert… …but WHAT, WHERE and HOW

76. Composting and Greenhouse Gases Methods & Technologies Hauling Distance

77. Composting is Net Negative in GHG impacts.

78. Composting is Net Negative in GHG impacts. Composting releases negligible methane and nitrous oxide

79. Composting is Net Negative in GHG impacts. Compost application increases total carbon retained in soil

80. Composting is Net Negative in GHG impacts. Compost application reduces need for GHG intensive artificial fertilizers

81. Composting is Net Negative in GHG impacts. Compost application increases standing biomass.

82. Composting is Net Negative in GHG impacts. http://cli.gs/EPAreport for EPA report

83. Does Method Matter? Range of inputs. vs. Potential for net carbon retention in soil vs. Soil amendment quality of product. vs. Contaminant levels in product

84. Three Sources of Organics 60,000 Tons Per Year Composition of Disposed Organics

85. GHG from Transportation How far is material transported? What kind of fuel is used? Can transportation requirements be reduced?

86. Current Organics End Points

87. DISCUSSION