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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: Richard Gertman, Environmental Planning Consultants


Local Government - Peter Slote, City of Oakland (PDF)

In 2005, Oakland switched its 95,000 single-family households from 2-bin recycling to one-cart single stream recycling, and later this year will introduce single stream to 55,000 multi-family units. The selection of single stream happened in the context of a number of necessary changes to the residential program, including: the addition of food scraps to yard trimmings collection, the change to weekly yard trimmings collection from bi-weekly, and fleet reconfiguration. Many jurisdictions' decisions to single stream or not to single stream are similarly intertwined with other program issues.

The possible downsides of single stream for local governments depend on the particular program configuration. For example, if a jurisdiction collects and processes its own material it would be exposed to product quality claims and the potentially restricted markets that single stream materials can be sold into. Likewise if a jurisdiction uses a contracted hauler/processor and has a risk- and-or reward-sharing arrangement with the contractors, then the jurisdiction would be similarly exposed to product quality problems and potentially limited markets.

If Oakland processed its own materials in a municipal processing plant, the classic arguments for ensuring high quality product - greater assurance of access to markets during difficult times, and greater flexibility to ship to different markets - would have changed the political calculus of the choice of single stream.

Peter believes that single stream's impact on product quality (the amount of glass in a bale of paper, for example) is affected less by contamination of non-program materials by residents, than by cross contamination of acceptable program materials during single stream processing. While a local jurisdiction can have an effect on contamination at the curb through education and contract management, it has less influence on the processing side when its tons flow into large, regional single stream facilities that process tons from multiple jurisdictions.

In the larger picture, single stream supports the off-shoring of value-added manufacturing. An argument could be made that industrial practices such as single stream recycling support the trade deficit.

If residential recycling were treated as an industrial practice, local governments would recognize single stream's impact on local and regional domestic manufacturing infrastructure, jobs and tax revenues. But single stream is so appealing that local governments are disconnected from some of the larger potential outcomes of our programs.

Audience Question: How can you tell how much residue is yours?

Peter replies that you can't determine that for sure when you share a processor with several other jurisdictions. You have to accept the joint residue rate.

Local Government/Processor - Donna Perala, City of San Jose (Powerpoint)

San Jose, the 11th largest city in the U.S. with nearly one million residents, has been nationally recognized in the past for its high-quality, multi-sort recycling program. Its transition to single stream on July 1, 2002 was challenging, but yields a number of valuable lessons.

With the new program, the city was unequally divided between two different collection companies - one providing service to 75% of the single family homes, and the other serving the remaining 25% plus all the multi-family units in the city. Each of the contractors also operates with significantly different business models.

San Jose was proud of the many collection categories it had been able to introduce in its previous program and did not want to remove any of them for single stream collection. So, in addition to the common single stream categories of glass, paper, plastics and metals, San Jose residents also recycle plastic bags, aseptic packaging and textiles. These additional items present their own challenges in single stream collection.

After a difficult start-up the first year - including a nearly five-fold increase in its residue rate (hitting an average of 30%) and an actual decrease in diversion - San Jose is now able to say its program is on its way to meeting its performance standards. The city has seen single-family recycling tonnages increase by 25%, and diversion by 11.5%, above that which was achieved under the prior source-separated system. San Jose's residential diversion rate is now at an all-time high of 49.5%.

Donna reported on some things San Jose has learned in its transition to single stream:

  • The Pay As You Throw system can encourage some residents to put extra garbage in their recycling carts in order to avoid additional garbage fees.

  • Large recycling carts may provide contamination opportunities when drivers cannot see the materials as they could with open, source-separated bins.

  • The trade-off for collection efficiencies and convenience is higher contamination and a greater need to sort materials effectively at the MRF.

  • San Jose's commitment to highest-and-best-use goals with regard to paper have been compromised, and some paper shipments have been rejected.

  • With single stream, outreach to targeted audiences is more critical than ever in order to educate residents about what goes in each cart.

  • The collection and processing companies' business models can present some significant challenges as well as opportunities.

By comparing the impact of the different business models of San Jose's two service providers, Donna showed the critical difference that business configurations and contract options can make in achieving a program's goals.

Business Model #1, in which the collection contractor owns and operates its own MRF, motivates the contractor to maximize diversion in return for potential contract extensions, bonus payments, reduced disposal costs, and avoidance of solid waste fees. In FY 2003-04, this contractor diverted 41.6%, with 7.6% residue, installed new sorting equipment, started a garbage composting pilot program, and paid to recycle difficult materials.

Business Model #2, in which the collection contractor subcontracts out the processing of recyclables, provides minimal incentive to maximize diversion because the subcontractor has no direct relationship to the City and is not involved in many contract issues. Any bonuses go to the hauler, not the processor. Conversely, the hauler, not the processor, pays for disposal of residuals. This has resulted in minimal incentive for the processor to maximize material recovery, invest in new processing technology or to innovate, resulting in 31.6% diversion and 17.3% average residue in FY 2003-04.

In order to inform residents about using the new programs, San Jose has spent over $2 million on single stream transition outreach and another $350,000 per year on on-going outreach, including going door-to-door to 2000 households in targeted areas last year. Haulers are also issuing non-collection notices to households not meeting standards for clean recyclables.

Donna cautions that contract incentives can help make single stream effective, but cities should work closely with their contractors in establishing the terms of any subcontracts. In particular, make sure appropriate incentives are in place and that procedures have been established to maintain control of the materials stream.

And yet . . . despite their difficulties, San Jose still believes that single stream is worth the trade-offs because of reduced labor costs, fewer worker injuries, increased participation and diversion, and increased tonnages of recyclables. They believe that updated technology and ongoing education will help address material quality issues.

Manufacturer - Jay Simmons, Norpac/Weyerhaeuser, Newsprint

NORPAC is a joint venture between Weyerhaeuser and Nippon Paper that produces over 2000 metric tons of newsprint per day on three world-class paper machines. It began deinking #8 ONP (old newspapers) in 1991 and currently consumes over 250,000 tons per year, including from California. Jay is the Deink Process Engineer.

Because NORPAC's customers are intensely focused on quality, the mill has had to implement one of the most intensive raw materials sampling and testing programs in North America. Samples of approximately 300 pounds each are sorted for Outthrows (fiber-based contaminants, e.g. the wrong type of fiber delivered to the mill, such as OCC at a newsprint mill) and Prohibitives (non-fiber contaminants such as plastics, glass, metals).

As more suppliers have shifted to co-mingled collection and processing systems, the overall quality of NORPAC's ONP has declined significantly, with Outthrows that had been at no more than .5% now increasing to nearly 6% and Prohibitives going from zero to 1.3%.

Comparing different suppliers shows even more dramatic impacts. The Outthrows in one supplier's bales jumped to over 21% when it switched to co-mingled processing and its Prohibitives added another 3.5% even though it kept glass separate. This means that the mill was having to landfill nearly one-fifth of the recyclable materials it had bought to make its products and then buy replacement fiber as well.

Glass at first appeared to be a very small .2% but Jay made clear that with the mill's 700 tons per day of ONP consumption, glass quickly adds up to 2800 pounds that must be removed daily.

NORPAC has seen a number of problems develop from the use of co-mingled processing:

  • Increased dangers to employee safety, including glass shards, airborne fine glass particles, and hazards such as hypodermic needles, rotting food and personal care products

  • A four-fold increase in annual maintenance costs

  • An 800% increased yield loss at the pulper from inappropriate fiber and Prohibitives that must be sent to the landfill, coupled with an 8-fold increase in additional fiber that must be purchased to replace the rejects at an annual cost approaching $2 million. Click Here for a picture of the huge amount of plastics lost to recycling after going through the newsprint mill's drum pulper.

  • Increased "stickies" (adhesives) in the pulp, mostly from OCC (old corrugated cardboard) that should not have come to a newsprint mill, which can create the potential to shut down the paper machines. Dealing with the increased stickies has cost NORPAC an additional $2/ton in operating costs.

Jay presented a number of potential solutions:

  • Work with suppliers to improve their ONP quality, as Portland Metro does

  • Develop economically viable processing and sorting equipment that can consistently produce ONP #8

  • Develop economically viable mill processing equipment that can more substantially remove the contaminants, helping to reduce maintenance costs (although still not reducing disposal and displaced fiber costs)

  • Improve the whole recycling industry's focus on getting each recyclable material into its correct recycling stream. When the wrong recyclables end up at a pulp mill, they go to a landfill and increase the costs of producing a finished product.

Audience Question: At what point does virgin material come into play, given higher costs for recyclables?

Jay replied that recycling recycled fiber at NORPAC has always been more expensive than virgin fiber but he needs to keep the deinking plant running to maximize the mill's economics and provide fiber to all three paper machines. Therefore, while he can shift to using some additional virgin fiber, he can't shift to a major increase.

He emphasized, though, that this answer is specific to his particular mill. Someone from a different paper mill might give a very different answer, depending on the specific facility and the products that it makes.

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Benefits of Single Stream

Manufacturers' Experiences with Single Stream


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