Compost Rules Have Changed

Our region’s only commercial compost manufacturer, A1 Organics, has changed what materials they accept from all communities along the Front Range. These changes are in response to contamination challenges across the region. If we all do our part, A1 can continue to create clean compost that can be used to revive soils and grow nutritious local food.

Only compost:

  • Food scraps
    • Including meat, bones, dairy, coffee grounds and eggshells.

  • Plant and yard trimmings
    • Leaves, twigs, flowers, grass and other lawn trimmings.

If it was on your plate or grew in your lawn, put it in the compost bin. Please place materials loose in your bin.

Compost food scraps, grass clippings, leaves, flowers and other yard trimmings.

Download and print the new sorting sign:

New Compost Sign

Have questions? Here are some answers! 

If it isn’t food scraps, yard or plant trimmings, it doesn’t go in the compost bin.

Keep these out of your compost bin – they belong in the trash:

  • All compostable packaging and products, including certified compostable utensils, cups, plates and to-go containers. Please do not put cups in the recycling stream. Disposable plastic and compostable cups are not recyclable.
  • Paper products, like towels, napkins and shredded paper.
  • Pizza boxes. Please throw away the greasy half of the box and recycle the clean half.
  • Coffee filters and tea bags. Dump coffee grounds and tea leaves into your compost bin and trash the filter or bag.
  • Most bags are not allowed, including large certified compostable bags used to line bins. Keep plastic bags out. Check out A1 Organics' website for a list of allowed compostable bags.

What about lawn and leaf bags?

Many waste haulers are still collecting large, brown paper bags used for yard trimmings. These bags must be left next to your compost bin. Please check with your waste hauler for more information. Large yard trimmings, like branches, can be taken to Western Disposal’s Yard Waste Drop-Off Center for a reduced fee.

Do not compost plastic or large compost bags, produce stickers, rubber bands, twist ties, coffee filters, tea bags, greasy pizza boxes, paper products or takeout containers.

Got bag questions? Reach out to your waste hauler for more information.

The Front Range has one regional compost manufacturer, A1 Organics, where all our local waste haulers take compost for processing. A1 has changed compost sorting rules because they are experiencing high levels of contamination in the compostable materials they receive from businesses and community members across the region.

Plastic, glass, metals, latex gloves and more are mistakenly placed into compost bins. When composted, these contaminants break down into sharp pieces or microplastics, leaving A1 with a product they cannot sell.

On the other hand, food scraps and plant trimmings make excellent compost for gardens and farms. Read A1’s notice to haulers and municipalities.

A pile of clean compost versus contaminated compost.

For now. While we cannot predict how guidelines might change in the future, we know that quality compost is made of food scraps and plant material. We also know that phasing out all disposable products, including recyclable and compostable to-go containers, is part of building a better climate future.

Compostable bags often contain and conceal contamination. Help A1 and your waste hauler make sure your compost is free of contaminants by skipping compostable bags.

Note that there are two exceptions to the no bag rule:

  1. You are allowed to use small CMA-approved compostable bags. Bags must be three gallons or smaller. Check out A1 Organics' website for a list of accepted bags.
  2. Many waste haulers are still collecting large, brown paper bags used for yard trimmings. These bags must be left next to your compost bin. Please check with your waste hauler for more information.

Go bag free and simply rinse out your indoor compost container. If it gets stinky, give it a quick rinse from the hose, swish it around and pour the water directly onto your lawn or trees. You can also line your compost bin with a thin layer of grass or leaves to help absorb moisture.

Kitchen compost bin without a bag

Help protect our waterways by not dumping water with food and soap residue into the street. Storm drains in our community lead directly to local creeks.

There are multiple reasons.

  • For every certified compostable product, there are several more look-alikes that seem compostable. In truth, they often contain harmful plastics.
  • Unfortunately, the volume of contamination A1 receives due to misleading labeling and non-compostable look-alikes makes any packaging or product too costly to accept.
  • The same is true for paper. Many paper to-go containers are coated in plastic. This coating leads to microplastics in compost.
  • Compostable bags often contain and conceal contamination.

Please note: Paper that has no plastic coating, like paper towels, facial tissues (that are not synthetic) and coffee filters are compostable in your backyard compost. Learn more about backyard composting!

No, compostable products are not recyclable. Please put them in the trash.

Compostable products were not commonly used until relatively recently. As their popularity has grown, they have spurred a rush of look-alikes in the marketplace. While compostable bags and food containers can be useful, the task of identifying what is actually compostable is next to impossible.

Absolutely! Two of the of the most impactful ways to help are to:

  • Use reusables whenever possible.
  • Bring your reusable mug to a coffee shop.
  • Stash a set of reusable utensils in your bag or car for easy access on-the-go.
  • Have your to-go packed in DeliverZero reusable containers.
  • Know before you throw. Checking out our Waste Sorting 101 guide for more local waste sorting knowledge.

Reuse services and products are on the rise, so encourage your favorite restaurants and companies to ditch disposables and use reusables instead.

Plant and yard trimmings can always be put in your curbside compost cart. In Boulder, residential compost bins are bundled with your trash. So, if you’d like a larger compost cart, please check with your waste hauler.

Many waste haulers are still collecting large, brown paper bags used for yard trimmings. These bags must be left next to your compost cart. Please check with your waste hauler for more information.

Large yard trimmings, like branches, can also be taken to Western Disposal’s Yard Waste Drop-Off Center for a reduced fee.

Starting April 1, compost truck loads containing anything other than food scraps, plant and yard trimmings will be refused by the company and sent to the landfill.

Please contact your waste hauler for more information.

The compost stream is not the same as the recycling stream. At a recycling plant, human sorters see contaminants like plastic bags and pull them off the sorting line by hand. Automatic equipment like screens and optical sorters also help separate materials.

Compost is not so tolerant. By the time compostable materials arrive at a compost plant, they are already a gooey mess. Imagine pulling plastic stickers off rotten banana peels.

Compost is ground and processed through screens, but small pieces of plastic, glass or aluminum will remain in the finished compost product. Farmers and other compost buyers need clean, nutrient-rich food scraps and yard trimmings. They don’t want to grow our food using compost contaminated with glass, plastic and metals.

A1 is not the only compost manufacturer making these changes. Many commercial compost manufacturers have simplified their guidelines because of contamination challenges and a rising demand for quality compost. This has impacted programs in other early adopter composting communities, such as Portland, Seattle, Vermont and California.

Creating policies and infrastructure that support the success of compost are becoming key priorities on the state and local level.

New policies are being introduced, including:

  • A new Organics Waste Diversion bill that will direct the Colorado Department of Public Health and Environment (CDPHE) to make recommendations about banning food and lawn trimmings from the landfill. The CDPHE will study infrastructure needed to divert these materials into better uses, like compost.
  • A Truth in Labeling bill would require all disposable food service products to be certified compostable and labeled as such. This would help prevent non-compostable look-alike products from ending up in our compost stream.

New infrastructure is being researched and proposed:

  • Stakeholders are looking at funding and creating infrastructure solutions ranging from prescreening for contamination at compost transfer locations to building additional composting sites at other locations.
  • Eco-Cycle and other local organizations are exploring smaller compost systems for farms and large generators, like universities or apartment buildings.

Reusable Alternatives

The city has partnered with two companies to help local businesses and diners switch to reusable products.

  • One of the companies, called DeliverZero, stocks businesses with reusable takeout containers that can supplement or replace disposals.
  • The other, called r.Cup, provides large events with reusable cups. These companies make it easy for businesses to choose reusable containers while saving money on single-use packaging.

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