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Zero Waste Hierarchy

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You’ve probably heard the term Zero Waste before, but not been sure about what it meant. 
 
The peer-reviewed definition of Zero Waste by Zero Waste International Alliance involves “designing and managing products and processes to systematically avoid and eliminate the volume and toxicity of waste and materials, conserve and recover all resources, and not burn or bury them.”
 
Notice the last part disqualifies burning or burying waste. Unfortunately, the U.S. Environmental Protection Agency still includes incineration (“energy recovery”) in their Waste Management Hierarchy, a concession to the incineration industry that makes achieving zero waste impossible.
 
Like it or not, there is a landfill at the back end of any waste system. There are three main options for what to do with the waste we fail to eliminate:
Incineration (and landfilling ash) is the most polluting and expensive option
Direct landfilling is bad, but preferable to incineration
Digestion before landfilling is the best option, so that the remainder is stabilized to avoid having gassy, stinky landfills.
 
The last is part of the zero waste approach, minimizing the volume, toxicity and nuisances of landfills. Incineration includes experimental gasification, pyrolysis, plasma and trash-to-ethanol schemes), where the toxic ash, slag or other residue still must be landfilled—unless they try to get away with something really inappropriate, like pretending ash is a useful building material, or dumping digested trash on farm fields.
 
After years of careful study, Energy Justice Network has designed its own Zero Waste Hierarchy, with each of its ten steps summarized below (and in the graphic).
 

 
1) Redesign
 
Products that are entering the waste stream need to be redesigned to be compostable or recyclable, be sourced from recycled materials, or made to last longer. 
 
2) Source Reduction
 
Everything from replacing toxics with non-toxics, using less toxics, encouraging people to consume less through advertising (or less advertising), and reducing packaging through bans or taxes (such as on plastic bags).
 
3) Reuse & Repair
 
Instead of throwing things away, fix what is fixable or use products for other purposes. Examples include Freecycle, Thrift Stores, and repair shops.
 
4) Source Separate
 
Pre-sorting recyclables, compostables, and trash before tossing them. 
 
5) Recycling
 
The best version of recycling avoids the single stream or “one bin for all” concept, and instead counts on consumers to take a few seconds to sort out their own paper, plastic, and glass, making the whole process more economical. 
 
Other relevant items can include “Pay As You Throw,” which charges consumers per bag for tossing away trash, which studies show can instantly reduce waste generation by 44% on average. State bottle bills are also crucial, as are recycling programs for electronic waste and household hazardous wastes.
 
6) Composting
 
Composting in rural areas is as simple as dumping scraps into a pile in your backyard, but in urban areas there needs to be weekly curbside collection of organics. Food waste is the second largest component of landfills, about 18%. 
 
While organic compost can be used for farms, landscaping, and gardens, sewage sludge is toxic and should not be included in the mix. 
 
7) Research
 
After taking the above steps, government, industry, and the nonprofit sector must take the time to study what sorts of products are still making it into the waste stream. Once that’s determined, let’s require producers to take responsibility for creating their waste, while considering bans and taxes that will ensure the proper removal of these products from the waste stream. 
 
8) Material Recovery
 
Recyclables that don’t get sorted out earlier need to be pulled out downstream. This is only a last resort and shouldn’t replace pre-sorting or composting. 
 
9) Biological Treatment
 
If there is still an organic component to the remaining waste, it should be aerobically composted (or anaerobically digested—a biological process of breaking down waste in absence of oxygen—followed by composting). Treatment will reduce the odor of landfills and remove the potential for the landfilled waste to produce methane, a greenhouse gas 86 times more potent than CO2.
 
Municipal waste residue cannot be used as fertilizer or soil amendments. 
 
10) Stabilized Landfill
 
After every single one of the above steps have been taken, there may still be a small leftover waste stream (minute compared to current levels, and more of a reduction than incineration provides). The key to stabilized landfilling involves storing waste in separate cells, and not gearing the landfill towards energy generation, which typically involves stimulating gas production (and more gas leakage).