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Single Stream: Closing the Loop
Taking A Whole Systems Approach
Sacramento, CA
May 23, 2005



Overview Design and Agenda Introduction

Morning Presentations

Benefits of Single Stream Challenges of Single Stream Recycled Product Manufacturing - What's the Future?

Afternoon Break-Outs

#1 - What Are We Building? #2 - Do We Have All the Right Tools? Thought Questions


Wrap Up Organizing Photos


We began with three panels designed to hear from each recycling system sector about the Benefits of single stream and then from each sector about the Challenges. Since people overwhelmingly said they do not know much about manufacturing, our third panel brought manufacturers together to give insights into their processes and issues.

These morning panels were intended to give the Roundtable group a common foundation of information to build on in the afternoon discussions.


Moderator: Delyn Kies, Kies Strategies


Local Government - Lynn France, City of Chula Vista

Collector/Processor - Richard Abramowitz, Recycle America/Waste Management

Manufacturer - Tamsin Ettefagh, Envision Plastics

Local Government - Lynn France, City of Chula Vista (Powerpoint)

Lynn France, Conservation Coordinator for the City of Chula Vista, CA, has many years of previous experience working for both a local government processor and an independent collection company. Her presentation highlighted how California's AB 939, which mandates local governments to achieve a minimum of 50% diversion from landfills, changed recovered materials' market signals. Prior to AB 939, manufacturers could control the volume of material recycled through pricing and quality requirements. Lower prices led to reduced volumes, while higher prices increased volumes.

But once AB 939 and curbside collection programs were implemented, volume was continuous, with no reference to price signals. The resulting lower, and sometimes even negative, values undermined processors' concern for the quality of materials delivered to end-users (manufacturers) and the diminished revenues increased the cost of curbside programs. That's why, she said, the solid waste industry looked for ways to redesign and retool for greater efficiencies in collection and processing.

In 2002, Chula Vista converted its source separation curbside recycling program to single stream with automated collection. It also changed to a variable rate structure. The collected commodities remained the same as the previous program - paper, bottles, cans, and plastics, with yardwaste collected separately in the resident's own standard trash can or a special greenwaste cart.

Among the benefits are:

  • Residents like not having to separate, bag and tie their materials. They put more recyclable materials out, in part, Lynn believes, because the considerably larger carts convey the message, "Hey, the city really does want your recyclables!"
    "You get what you telegraph you need," she says.

  • Less litter on the streets on collection days

  • More materials that previously had gone into the trash, stimulated by the new rate structure

  • 100% increase in recycling volume. (Interestingly, the amount of trash remained the same. Lynn attributes that to the improving economy, so people have more to discard now than before the new program began.)

Chula Vista's single stream program has a 7% contamination rate (trash, nonrecyclables) compared to a 2% contamination rate for the previous source-separation program.

Lynn pointed out that converting to a single stream program requires a major public education campaign, but this revitalizes recycling participation and awareness. Also, in order to adequately process the single stream materials, Edco, the MRF that Chula Vista delivers to, needed to do considerable retooling of both its collection and processing operations in order to maximize efficiencies and minimize contamination of commodities.

Audience Question: Chula Vista made three changes at the same time: 1) automated, 2) single stream, and 3) changed to unit pricing. So why does Lynn attribute all the benefits to single stream? Aren't many of them because of the automation?

Lynn answers that she thinks it's best to make this set of changes all together, and to her it really isn't important to know what percentage of benefits is tied to one or the other.

Collector/Processor - Richard Abramowitz, Recycle America/Waste Management (Powerpoint)

"Diversion is King!" exclaimed Rich Abramowitz at the start of his presentation. Should it be? This began a theme for many discussions throughout the day.

Waste Management/Recycle America Alliance (RAA), California's largest recycler of municipal solid waste, operates 24 recycling facilities in the state, 11 of them single stream. It markets half a million tons of materials from California each year, not including glass, and has invested over $25 million in single stream technology for California alone.

Historically, 25% of the residential materials stream has been recycled while 75% has gone to disposal. RAA sees recycling trending towards flipping those percentages, moving towards goals of recycling 75% of residential materials. It also sees that the formerly grade-specific commercial recycling system is changing to one that is grade-indifferent, with OCC, SWL and SOP mixed together for commercial single stream processing.

RAA has seen these single stream changes result in:

  • Higher participation rates
  • Higher recovery rates (20-30% in California)
  • Reduced unit costs (time per stop, trucks on street, processing costs per ton)
  • Reduced collection and MRF employee safety risks
  • Reduced total recordable incidence rates (TRIR)
  • Reduced employee turnover
  • Reduced worker compensation rates
  • Optimized fleet utility
  • Increased recycling opportunities
  • Improved aesthetics and convenience
  • Making residential recycling economical and sustainable
  • "Securing" and growing the residential fiber stream

MRF equipment, while expensive ($1-6 million), can increase processing production to 30-40 tons per hour. Screening and optical equipment has been improving auto-separation of materials. Improving MRF operations makes sorting easier for line workers and creates flexibility in meeting market changes.

But there are still challenges:

  • Residue rates for single stream processing facilities run 6-8%, compared to a typical 2-stream MRF that runs about 4% blended residue of fiber and containers. RAA can reduce their single stream residue to 4% with no-sort glass and plastic technologies that separate materials categories by optical sensors.

  • Typically, about 50-60% of glass breaks in the curbside collection process. The percentage generally increases to 60-90% with single stream, depending on vehicle and compaction ratios. RAA is tackling this problem through greater use of optical sorting and better screening.

  • Quality can be an issue on fully-automated collection routes. RAA is improving quality through manual and semi-automated routes and checking set-outs.

Rich quoted Pat DeRueda, RAA's new President who attended the Roundtable, in pointing out one of the biggest challenges facing recycling: "We've got to make sure that what's going into the bales is meeting the specs of the mills."

Manufacturer - Tamsin Ettefagh, Envision Plastics (Powerpoint)

Envision Plastics began in 2001 when it bought two plastics recycling plants from FCR and Union Carbide, said Tamsin Ettefagh, Vice President of Sales and Purchasing. Its second plant is located in Chino, CA. The company has 60 employees and processes 4.5 million pounds of HDPE plastics per month.

Envision grinds, washes, and sorts approximately 2,500,000 bottles each day, then extrudes them into pellets. It then sorts close to a million flakes per minute into 250,000 different colors, which in turn are used to make bottles for familiar consumer products such as Gain, All and Downy.

Tamsin gave a brief history of recycling collection trends, noting that in 1997 there were four single stream recycling systems in the U.S., while today there are 95. She saw as advantages of single stream:

  • Lower collection cost - as just one example, automation averages pick-ups from 800-1000 homes per day, compared to 400-600 for manual pick-ups with driver and helper

  • Easier recycling for residents - wheeled containers have over 5 times the room of bins and are easier to get to the curb, lids keep materials dry and contained (Tamsin believes that increased participation rates have more to do with the convenience of the carts than with not having to sort)

  • Increased recycling rates - when the East Valley District of the City of Los Angeles went to single stream in 1998, net recycling tonnage increased from 1900 tons per month to 4500

  • Innovation in recycling equipment

  • Increased tonnages for MRFs to process, which lowers unit costs

However, there are also weak points to single stream:

  • Processing costs are higher because, with all commodities mixed together, more labor is required to sort it; sorting systems are much larger and require more MRF space; and initial sorting equipment investments are high. An AF&PA study reports that systemwide expenses increase $3/ton for paper collected in single stream systems. While curbside collection costs average $15/ton less than previous systems, processing averages $10/ton more and manufacturing averages $8/ton more

  • End products are more contaminated

  • Inadequate public education and the wrong equipment in place can result in millage loss increases (materials that were collected for recycling but could not be used because of contamination or being sent to the wrong type of mill) at the MRF and the manufacturing mill

  • Paper mills say that 39 million pounds of plastics were sent to their mills because of poor sorting at single stream processors

  • Glass cullet has increased wear and tear on paper mill equipment

  • Mixed colors predominate in glass cullet from single stream, which makes it harder to market

Nevertheless, Tamsin favors single stream for plastics recycling because the #1 problem for plastics recyclers is lack of raw material (specifically PET and HDPE bottles). Despite an increase in pounds of plastic generated each year, recovery rates for plastic bottles are declining. Yet 96% of plastic bottles are PET and HDPE.

Education and follow-up are key to a successful single stream recycling system.

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Challenges of Single Stream

Manufacturers' Experiences with Single Stream


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