Better data needed to monitor successful recycling

'Green' bin in Salmon Street, Kingsbury this week

Green groups in Brent expressed fears that the new co-mingled recycling (everything put into one bin and emptied into one truck) would produce more contamination than the green box system where different materials were sorted at the pavement stage and put into different compartments of a lorry. This would result in more material being rejected at the recycling plant and ending up in landfill.

Now that the scheme has been running for some time I put in an Freedom of Information request to see if the amount of recyclates collected, which have increased now that some plastics are collected, was affected by increased contamination.

Unfortunately some data is not recorded so it is hard to get a full picture but the recent rejection rate seems to vary between  4% and 12%. It is argued that the recycling rate has still increased taking this into account.

Here are the full answers. Thanks to Chris Whyte for another quick response (Answers in bold)

1. What proportion of material collected in the co-mingled 'blue top' bins has been rejected at the Material Recycling  Facility (MRF)  since the new system was introduced as:

  a. Contaminated. The most recent sampling shows the prohibited fraction can range from 4% to 12%

b. Not recycled under the present scheme: As above. This is the same waste. The overall recycling rate has increased from 31% to 45% and this accounts for the prohibited fraction.

 2. How does this proportion differ from the previous separated green box system? Not recorded. This was a different system that saw prohibited items removed at source. Thus there is no real comparison.

 3. Please provide a table to show whether the proportion rejectedhas declined over time as residents have become familiar with the system. Regular sampling is not undertaken and the prohibited can
fluctuate from period to period. Our records show an overall increase in the amount, and percentage of, waste recycled since the new service began.

 4. If data is available please provide the above information for recyclables collected from communal recycling bins from flats. Not separately recorded.

5. What has been the cost of sending these rejected materials to landfill? There is no additional cost to the council for landfilling prohibited waste that is rejected. The  cost is contained within the £22
per tonnage charge for accessing the Material Recycling Facility (MRF). This represents a £70 per tonne reduction on waste collected for landfill through the refuse service.