Estimating Annual Waste Tire Generation, Diversion and Disposal in California

1. Estimating Annual Waste Tire Generation, Diversion and Disposal in California A study for the California Integrated Waste Management Board Shawn Blosser Matthew Newman Trisha McMahon Rob Wassmer Presented By:

2. Building A Model • Review of Estimation Methods in Use • Evaluation of Competing Methods • Model Overview • Data and Parameters Used • Results • Diversion & Disposal

3. Alabama, Delaware, Massachusetts, and Wisconsin do not track waste tire generation but are aware of the one tire per person per year metric. These states are reflected in the "states without waste tire generation estimates" category. Estimating States • Contacted all other 49 states # States States Without Waste Tire Generation Estimates 12 States With Waste Tire Generation Estimates 37 Total 49

4. Per Capita Standard is Widespread • Over half used standard of 1 tire per person # States States Using Unknown Methodologies 2 States Using 1 Tire/Person/Year 23 States Using Other Methodologies 12 37 Total Missouri and Nevada are counted in other methodologies even though they compare to 1 tire per person Maryland, Vermont, and Wyoming methodologies may represent the use of one tire per person per year. Additional detail on these methodologies could not be obtained.

5. Three Other Methods In Use • New tire sales, waste tires received, state models Methodology # States State(s) MO, NV, OK, VA Track Revenues Collected on Tire Sales 4 Track Waste Tires Collected 5 AZ, HI, NC, OH, TN Industry Survey 1 SC State-Created Model Estimate 2 FL, WA Total 12 Oklahoma appears in track revenues, but it also tracks waste collected.

6. Basis of Per Capita Metrics • Rubber Manufacturers Association (RMA) standard of 1 tire per person • Replacement tire sales + Tires on scrapped vehicles = 299.5 million in 2005 299.5 million/ 296.4 million people =1.01 PTEs per person/year • Asked states to report waste tire generation: 299.15 million ≈ 1.01 PTEs per person/year.

7. Per Capita Metrics Are Underestimations • Does not account for variation in tire weights and sizes • Relies on self-fulfilling survey: • 1 tire/person/year standard adopted by EPA • At least 20 states use the metric as their sole estimation methodology

8. Tracking Tire Fee Revenue Is Not Accurate • Underestimates: • Captures just one of many flows of waste tires • net migration, internet sales, net imports, illegal tire sales, industrial waste • May not vary by tire size • Oversimplifies: • Weights/sizes/characteristics of tires sold change over time • May not count government vehicles

9. Two States UseCustom Models • Existing models oversimplify: • Florida model based on tire fees • Washington based on vehicle registration • Do not account for other tire flows • Ignore the rate at which tires enter the waste stream

10. What Should A Model Do? • Fully incorporate all tire flows • Track tires over their lifespan • Account for variations in tire weights • Be flexible, state-specific, modifiable, and updatable

11. What Does Our Model Do? • Calculates the number of new tires sold in or entering the state every year • Assigns these tires to tire categories by weight • Estimates the length of time before they enter the waste stream • Tabulates the weight of these waste tires • Computes the results in PTEs and Tons

12. CA Tires “On the Road” Waste Tires Tires Entering CA Assigned to Tire Categories based on… Passenger Vehicles Autos, SUVs, Pick-ups, Vans, Motorcycles Model estimates that tires enter waste stream by category based on either (1) annual miles driven and tire life expressed in miles, or (2) industry estimates of tire life expressed in years NEW TIRES Passenger Vehicles Annual Industry Sales Data (U.S.) BOE Sales Data Light Trucks Light Trucks Cargo trucks, 2-axle trucks, etc. Medium Trucks New Tires Sales Not Included in BOE Data (Internet, etc.) Heavy Trucks Off-Road Vehicles Medium Trucks Semis & trailers Heavy Trucks Garbage trucks, etc. Breakdown of Estimated Tires “on the road” for that year Avg. weight per tire calculated by category using seller, manufacturer, or industry standards. Passenger reflects CA registration in a year. USED TIRES Net Population Migration from Census Off-Road Vehicles Construction and farm equipment Rubber waste from re-treading Re-Treading Medium & Heavy Truck Tires Only Waste Tires expressed in 20 lb. PTEs (Passenger Tire Equivalents)

13. New Tires: # of New Tires Sold: BOE Revenue # of Tires Sold on Internet: Modern Tire Dealer # of Tires Sold to government entities: Federal Highway Administration, CA registration stats. # of Tires Brought in from Out-of-State: Net migration, # of people per HH, # of vehicles per HH Tire Life: VMT for Passenger, Light Truck and Medium Truck: Federal Highway Administration Tread life for all types: National Highway Traffic Safety Administration # of Retreads for all types: Tire Retread Information Bureau Annual maximum life: Industry recommendations, RMA Tire Allocations: # in Passenger, Light Truck, Medium Truck, Heavy Truck, Off-Road: US Sales Distribution Statistics Average Tire Weight: Passenger: Tire Size Sale Statistics, Distributor Specifications, CA vehicle registration Light Truck: Tire Size Sale Statistics, Distributor Specifications Medium Truck: Manufacturer Specifications Heavy Truck, Off-Road: Scrap Tire reports % difference from new weight: CSUS survey, RMA, UK Environment Agency report. Overview of Model Parameters

14. Step 1: Calculate the Number of New Tires in CA • New tire sales in CA • New tire sales from out-of-state • Partially-used tires from net migration Our analysis shows that net imports, industrial waste, and illegal sales are insignificant sources of waste tires.

15. Passenger Vehicles Autos, Vans, SUVs, Pick-ups, Motorcycles P-metric tires Light Trucks 2-axle, single-frame trucks with 6 or more tires LT sized, smaller than 8.25” x 20” Medium Trucks Semi-Trucks and Trailers, etc. Tires sized 8.25” x 20” to 11” x 24.5” Heavy Trucks Garbage Trucks, etc. Tires sized 11” x 24.5” to 14” x 25” Off-Road Vehicles Construction and Farm Equipment Tires sized 16” x 20.5” and larger, plus farm equipment tires Step 2: Assign New Tires to Categories

16. Step 3: Estimate the Length of Time Tires are on the Road • Function of tire tread life, vehicle miles traveled (VMT), retreading, and time. *Tires wear out from use before 6 year limit is reached.

17. Step 4: Tabulate the Weight of a Scrap Tire • Calculated new tire weights for passenger, light truck, and medium truck tires • Based on most popular tire sizes for passenger and light truck, on popular brands for medium truck • Passenger average was weighted by registration data • Adjusted to reflect weight loss due to wear • Estimated heavy and off-road tires based on industry data

18. Step 5: Compute the Results • Follow tire cohort over the years • Estimate the number of tires that become waste each year • Sum waste tires • Divide by the Passenger Tire Equivalent (PTE)

19. Results • Average PTEs/person during 2005 – 2009: • 1.24 • Average total number of waste tires generated per year during 2005 - 2009: • 46 million PTEs

20. Average PTE/Capita 2005-2009

21. Sources of Waste Tires Average for 2005 to 2009 period.

22. The Variables that Drive Waste Estimates • Sales of new tires • Average weight of tires/percent lost to wear • Composition of vehicle fleet • Extent of retreading

23. Model Results Subject to Uncertainty • Range when average tire weight varies ±10% Low: 1.12Best: 1.24 High: 1.37

24. Diversion & Disposal • 2005 CIWMB estimate: • 30.6 million diverted, 40.8 generated • 75% diversion rate • Estimate segment of the market not included in survey • Assume similar to those included with 75% diverted • Use model generation estimate → 33.6 million diverted • RMA Estimates • 67.99% diverted in CA • National average rate is 86.6%