PV Sustainability Committee’s Tour of GreenWaste

The Sustainability Committee toured the GreenWaste Material Recovery Facility (MRF) in San Jose to better understand how our town’s waste is processed, how we are meeting the SB 1383 Composting bill, and to better address questions from our community. The management team at the facility was very eager to showcase the impressive sorting capabilities at the MRF and answer our questions, despite the fact that many are addressed on their website and in their Quarterly Newsletters (that are also available on their website). 

They are very proud that more than 70% of the incoming volume is kept out of the landfill and sent on to be transformed into new products They meet this level of recovery by sorting the contents of the 3 types of waste (blue/brown, green, gray bins) in complex streams. We were able to watch these streams move during our visit, and you can watch them virtually using the links at the bottom of this article. The streams are sorted by a combination of human workers and high-tech machinery. 

Your effort to properly sort your trash into your 3 (or 2) bins is greatly appreciated and vital for them to maintain that 70% level. It may look like everything is being dumped into one place within the trucks, but that is not the case. There are compartments and automatic diverter flaps inside the truck that keep the types of trash separate. 

Below are some of our take-aways.

Yard Waste Bin (Green Bin)

• The yard waste that is placed in your green bin is very valuable – it goes to a special facility in Gilroy where it is turned into high-quality compost for CA farmers. This is why they are very picky about what goes into that bin. Food waste should not be placed in the green bins, only landscaping material.
• Some steep/narrow areas of Portola Valley are served by trucks that have only 2 compartments, and so Yard Waste and Mixed Compostables (i.e., trash, black bin) are mixed together (and in this case, Yard Waste is treated like any other organic waste in the stream).

Recyclables Bin (Blue (or older Brown Bin)

• The most important thing about your Recyclables (your blue bin) is that they be kept clean and dry.  That means:
  • Your bin lid should be tightly closed on rainy days; dump any water out of your bin before adding recyclables, and tell GreenWaste if your lids are consistently left open by their team.
  • Liquids inside bottles should be emptied and (ideally) allowed to dry.
  • Excess food should be scraped from glass and plastic containers and not allowed to leak onto the other recyclables.
• Replace lids and caps onto plastic containers; this will keep them from getting stuck in the sorting equipment. Remove metal lids from glass jars/containers; those are recycled separately, and it saves time if they are simply removed first.
• While it’s true that there is very little market for plastics other than #1 and 2, nationwide, GreenWaste is constantly searching for and finding markets for the other types of plastic. We were told that they have a consistent and profitable market for #5 plastic, for example. So don’t assume you are “wish-cycling” when you toss out those plastic containers #3-7.  Let GreenWaste decide.
• Bundle clean Film Plastic (bread bags, film covering food packaging, etc.) in a clear bag and knot it. This keeps the bags from getting stuck in the gears and is more easily removed from the conveyor belt.
• Bundle non-clear plastic bags separately from the clear bags.  Opaque/colored bags have a separate destination from the clear bags, so this makes the sorters’ job easier.
• Don’t crush anything.  Robot arms pick certain items from the stream, and they work more efficiently if nothing is crushed (cans, plastic jugs, milk cartons, etc.).
• Place any shredded paper into a separate clear plastic bag and tie a knot, so that they can pull it from the process and avoid generating massive amounts of confetti in the machines!

Mixed Compostables Bin (Gray Bin)

• Ever wonder how on earth organic waste is picked out of the Mixed Compostable stream? Well, it’s actually not. The organic waste is what remains after everything else is picked out. The organics are sent for composting at GreenWaste Z-Best Composting Facility where the material is aerated, screened, and tested. GreenWaste has been in operation for decades and has already been in compliance with California’s new bill to reduce methane in landfills (SB1383) far in advance of other waste companies
• Don’t throw batteries in any of your bins. They contain toxic substances. Tape the ends and place them inside a clear plastic bag (one of your bread bags will do). Knot the bag and place it on top of your bin.
• Tie up wire and Christmas lights so they don’t jam the gears.
• Be considerate by not putting sharp items into your bins by themselves.  Place sharp items inside a bag or box and label it so no one gets hurt.
• There is almost no market for recycling Styrofoam, so limit what you get (when possible) and take advantage of the Styrofoam drives held twice a year at Ladera Church and Valley Pres.

Confused about What Goes Where? This GreenWaste page can be helpful when you’re in doubt.

The work you perform when you properly sort your trash results in lower costs for GreenWaste and ultimately a lower cost for the residents of Portola Valley.  So, thank you!

Below are the promised links.  Watching live was fascinating, but the virtual tours are a bit easier because we couldn’t always hear in the loud environment of the machinery. 

Introduction to GreenWaste facility and overview of process

Single Stream Recyclables (Blue bin)

Municipal Solid Waste (MSW) or Mixed Compostables (Gray bin)

Yard Trimmings (Green bin)

GreenWaste Z-Best Composting Facility - GreenWaste