67% of Central Contra Costa’s food and yard waste is not recycled

Contra Costa residents are being duped. Despite their efforts to sort food waste and yard trimmings from the landfill, 67% of the material sorted at the curb ends up there anyway. If you live in the Central Contra Costa cities of Danville, Lafayette, Moraga, Orinda or Walnut Creek, only one third of the yard clippings collected every week is actually being recycled and composted – the rest is being applied to landfills as Alternative Daily Cover (ADC) to cover garbage at local landfills where it rots and produces harmful greenhouse gasses rather than being composted into nutrient rich compost.

“The numbers don’t lie – if you live in Danville, Lamorinda or Walnut Creek, two-thirds of all your yard waste isn’t being recycled at all,” said Evan Edgar, Regulatory Affairs Director for the California Compost Coalition, representing organic material recyclers and compost operators throughout California. Edgar points to official state and local data revealing that of the 54,678 tons of yard waste collected in this area, only 21,487 tons has been recorded as being composted.


21 states in the nation have banned green waste from landfilling and instead send the material to be composted. California is the only state in the nation to allow green waste to be used at landfills as Alternative Daily Cover and count it as recycling. Edgar says large out of state corporations are exploiting this law to avoid handling the material responsibly as the customers intend.

The 22nd Annual Conference of the United States Compost Council is meeting in Oakland this week, January 26 – 29, at the Oakland Marriott City Center where composters around the nation are convening. The use of compostable materials in landfills promises to be a hot topic.

One of the hot button topics is the extent that green waste is mixed with food waste and used as ADC at landfills. California law strictly prohibits this practice. “In Central Contra Costa and other areas of California, solid waste companies are getting away with mixing yard waste and food scraps and using this mixture to cover garbage at landfills,” Edgar said. “This practice is illegal and regulatory agencies are looking the other way.”

At a state public meeting in Sacramento last week, the California Compost Coalition called for a statewide audit to determine the extent that green waste with food waste is being overused at landfills as daily cover.

Edgar referenced a report prepared by the state oversight agency, the California Department of Resources Recycling and Recovery, which documented that 17 of the state’s landfills were filled with up to 50% Alternative Daily Cover, where only 10% is needed to properly cover the garbage. These communities were also receiving recycling credits even through material was still ending up in the landfill.

“State law allows green waste to be used as alternative daily cover at landfills and count as recycling. There are state regulations that require the green waste to be processed, contain no food waste, and not be overused. Green waste used to cover a landfill and count as recycling is questionable, but to use this green waste and food waste as daily cover is fraud.”

Food and yard waste is not recycled

One of the most egregious offenders are the companies serving the Central Contra Costa County Solid Waste Authority. The Authority contracts with Waste Management of Houston, Texas to collect their cities’ weekly yard waste. It is Republic Services of Phoenix, Arizona that is responsible for the processing of Central Contra Costa’s yard waste. In Lafayette, Orinda and Moraga, for example, Republic is under contract to compost residents’ yard clippings at Republic’s Newby Island facility in Milpitas. There are no state or local records of any Lamorinda yard waste being composted at Newby Island.

67% of Central Contra Costa’s Food and Yard Waste is NOT being Recycled

“If you’re a resident of Danville, Lamorinda or Walnut Creek, you ought to be hopping mad that a majority of your yard waste is ending up at the landfill and not being composted at all,” Edgar said.

The Alameda County Waste Management Authority, StopWaste.org, located in Oakland, already bans green waste from landfilling, and has an upcoming mandatory food and yard waste collection program starting on July 1, 2014. The State allows not only green waste, but also construction and demolition debris and auto-shredder fluff to count as recycling according to StopWaste.org findings.

“California has lived with green waste being landfilled for 20 years. It is about time to phase out this outdated practice here locally and statewide as the compost industry expands to include anaerobic digestion technology to obtain energy from green waste and food waste,” Edgar added.

“Instead of landfilling green waste and food waste which create greenhouse gases, the compost industry can utilize these resources to make renewable energy and organic compost for agriculture driving our sustainable agriculture community forward, protecting the health of our water resources and supporting a low carbon economy.”

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  1. Deidra Dingman says

    The first paragraph of this articles includes the following statement indicating that majority of the yard clippings are “being applied to landfills as Alternative Daily Cover (ADC) to cover garbage at local landfills where it rots and produces harmful greenhouse gasses rather than being composted into nutrient rich compost’. It seems important to point out a fact because this statement is misleading. In order to become finished compost, yard clippings must first go through decomposition. .As organic matter like yard waste decomposes (rots) it produces methane (a potent greenhouse gas). Methane is produced whether yard waste decomposes (rots) in a compost pile or is used as daily landfill cover. Methane produced in landfills must be managed with landfill gas collection systems and in the case of the Keller Canyon Landfill it is used to generate energy. I am not suggesting that using yard clippings to cover landfills is better than composting, however thought it important to share a couple of facts specifically about emissions. As noted in this article, composting is a good thing which yields a soil amendment that can be used to help improve the moisture retention of soil, while providing nourishment to plants without the use of artificial chemicals.