As single stream collection is being adopted by many jurisdictions throughout North America best practices for collection and processing need to be developed. To date, studies with a focus on singles stream systems have been limited to Material Recovery Facility (MRF) processing. In the spring of 2006, the Region of York retained AET Consultants Inc. as the lead consultant to implement a project to determine the optimal level of compaction on single stream blue box (SSBB) recyclables and specifically, to identify the most favourable degree of compaction that maximizes collection efficiency while maintaining efficient MRF operations. The project focused on the following:

•  A survey of jurisdictions within Ontario, Canada and the United States on the subject of    collection and processing of blue box recyclables.

•  Process testing of SSBB recyclables collected at different rates of compaction through    York Region's MRF.

•  Analysis and reporting on the survey and MRF process test results.

The compaction composition study results showed that increasing compaction in collection vehicles does impact

MRF effectiveness. As noted by York Region, the results of this project have the potential to reduce blue box system costs, contain future per tonne costs and may lead to the establishment of a compaction policy. It was concluded that:

•  There needs to be MRF operational changes when processing compacted blue box     recyclables, such as a decrease in belt speed and/or increase in sorting staff and     equipment upgrades.

•  The MRF equipment supplier's compaction recommendation of 2.5 to 1 can be considered     valid if adjustments are made to the MRF operations. If operational adjustments cannot     be made, a lower compaction rate, such as 2 to 1 could be used as a 'better practice'.

•  The cost savings to collection, by increasing compaction, could offset the cost increase to     MRF processing resulting in an overall reduction in system costs.

Supplementary studies are recommended to evaluate the financial impact on collection by using more compaction vehicles. The full report is available on Stewardship Ontario's website at http://www.stewardshipontario.ca