Listed below are recent posts across all of CalRecyle's blogs.

  • What would you like your food waste to become?

    Here in California, we’re forging ahead with strategies to reduce food waste, which creates greenhouse gas in landfills, and put the resources we have to their best and highest uses.

    Organic waste in landfills decomposes and generates methane, a greenhouse gas 23 times more powerful than carbon dioxide. Forty percent—40 percent!—of the material currently going to California landfills is organic waste. Within that 40 percent is a lot of perfectly good food going to waste while people in your community are food-insecure. A lot of that food waste is obviously not edible—but read on to learn what it could become instead.

    CalRecycle is currently working on a framework to implement SB 1383, which passed in November and sets targets to reduce significantly the amount of organic waste going to landfills. SB 1383 also establishes a goal of recovering 20 percent of the amount of edible food waste that is currently disposed and diverting it for human consumption by 2025.

    We are really excited about this. We’re talking to grocers and other businesses that generate a lot of organic waste to get that 40 percent number down quickly—but we all have a role.

    Careful planning can keep you from buying more food than you need at the grocery store, and it will help you save money, too. Figure out how to incorporate your leftovers into another meal. And don’t be afraid to compost—it’s actually pretty simple.

    Sure, meal planning is tedious, and backyard composting is not as convenient as pitching your leftovers into the garbage. Some areas now have organic material pickup, but your waste management rates may have increased as a result of this new service. So it’s important to keep in mind these important greenhouse gas reduction goals, and fellow Californians who are going hungry, as you shop for your groceries and clean up after your meals.

    What do you want your uneaten food to become?

    1.    If you never buy it in the first place, and your grocery store ends up with extra as a result, that food could very likely end up being donated to a food-rescue group and made available to food-insecure people.

    2.    If you compost it in your backyard, it will save you water and enrich your own garden or landscaping, as compost helps soil maintain moisture and returns nutrients to the soil.

    3.    If you put it in an organic waste bin and roll it to the curb (check with your local jurisdiction! Some areas allow this, but many do not):

    • It could become compost for agricultural crops, where water retention ultimately reduces runoff and saves water on a much larger scale, and returns nutrients to the soil on a larger scale, making for more productive crop yields. (Read about California’s Healthy Soils initiative here.)
    • It might even go to an anaerobic digester and be converted into biofuel for city buses—or the waste management trucks that picked up the material in the first place!

    Or …

    4.    You could put it in the garbage and have it go to the landfill every week, where it will decompose along with all the other food waste, and generate more methane that accelerates the dangerous effects of climate change.


    You pick!

    There are a lot of us here on the planet, and a lot of us here in California, sharing a finite space and generating a lot of waste that needs to be managed. A lot of people are hungry, and we’re all breathing the air and drinking the water, so we need to manage the resources we have.

    Posted on In the Loop by Heather Jones on Feb 6, 2017

  • A Compost Bin for Every Challenge

    I live on a raccoon superhighway. We’re pretty close to a river and a creek, and the savvy critters use the storm drains to travel. This is fun for me and my neighbors—we get to see them shimmying up trees late at night, and sometimes they bring their little ones to the neighbor’s koi pond so they can learn to fish. (OK, maybe that’s not so cute.) There are also skunks, opossums, and the occasional rat family. The rats have been known to use the warmth of a compost pile to make a cozy nest for their babies.

    This makes composting kitchen scraps not impossible, but a little tricky. An open bin will not work for us, as rat families are not welcome. We have a plastic tumbling compost bin, which gets the job done and keeps the critters out, but it’s hard to open, and I have to remember to crank it every day or so.

    I think I found the perfect solution for my yard. A little gem of a publication on the CalRecycle website called Building your Own Composting Bin: Designs for Your Community has a bunch of great bin designs. My favorite is a  composter made from a trash can with a tight-fitting lid—it keeps the varmints out while letting in air, and it allows earthworms work their magic without my having to remember to turn the pile.


    This beauty took hardly any time at all to build. We bought the can for $25 at the hardware store, dug a hole in the backyard, drilled some holes in the can—in the bottom for the worms to get in and out, and in a ring around the top for air to get in—and we buried the can in the ground. (The directions said to bury the can 15 inches deep, but we were a little overzealous with our digging, so ours is deeper than that.) We won’t need to stir the pile because the worms will aerate it for us. It should be easy to keep smells to a minimum by covering our food scraps with dry leaves or soil (we left the dirt from the hole nearby to make it easy). The lid fits tightly, so hopefully the critters will leave it alone. If the raccoons figure out how to open it, bungee cords through the handles should keep them out. Of course, we won’t put in any meat or dairy scraps, but the worms will love our fruit and veggie scraps. 

    Composting at home is the cheapest, easiest, most Earth-friendly way to keep organic waste out of landfills. The gorgeous soil that’s created keeps our vegetable garden healthy and productive. We’re closing the loop—garden to kitchen, and back to garden again—with a minimum of bother. That’s my kind of DIY project!


    For more on composting, check out this CalRecycle composting guide.

    —Lisa Garner
    Lisa Garner is an environmental scientist at CalRecycle.

    Posted on In the Loop by Lisa Garner on Jun 9, 2016

  • The Greening of Commercial Compost

    Compost happens, as they say in the biz.  It’s true that, given enough time, most natural materials will decompose.  The whole idea behind “composting” is to optimize nature’s process by providing the right mix of carbon, nitrogen, water and air. Most commercial-scale composting in California is done in long, narrow piles called windrows, which are mixed regularly by a specialized piece of equipment called a windrow turner.  These enormous, diesel-powered critters range from 200 to 600 horsepower, but you’ll be traveling in hours per mile not miles per hour.  What if there was a way to replace some of that diesel using the sun?


    CalRecycle was involved in in a project, funded by the San Joaquin Valley Air Pollution Control District, involving the Association of Compost Producers, private consultants and local partners,  to see whether large piles of green materials could be composted  using small “bounce house” blowers powered entirely by the sun to pump air into the pile instead of being mechanically turned.  The point of the project was so see whether air emissions could be reduced during the first three weeks of composting, which is the time when most emissions of volatile organic compounds—aka VOCs—occur.  VOCs are important to the air district because they mix with oxides of nitrogen (NOx) from vehicle tailpipes to form ozone, a very dangerous air pollutant at ground level. Summer ozone levels in the Central Valley are some of the highest in the country, and per the federal Clean Air Act must be reduced.

    The same sunlight that helps VOCs and NOx turn into ozone can provide more than enough electricity to power a 1.5-horsepower electric blower using only one solar panel, and that energy can be stored in batteries so that pile aeration occurs day and night. A series of pipes laid under the composting material provide a path to inject air into the bottom of the pile, and it filters up to the top, keeping things happily aerobic.  To trap more emissions, the tops of the piles are covered with a layer of finished, unscreened compost, and kept damp with sprinklers, again sparing the air because the diesel-powered water trucks so common at windrow facilities get a little rest. 


    VOC emissions were reduced in this pilot project by 98 percent, diesel use was reduced by about 87 percent during those critical first few weeks of composting, GHG emissions were reduced by about half, and the amount of water used to keep the pile moist was reduced by 20 percent.  That’s quite a savings.  

    To reach California’s goal of 75 percent recycling and composting by 2020, and ARBs draft goal to get 90 percent of organics out of landfills by 2025, many new compost facilities will be needed.  No one type of facility will fit all communities, but all new organic materials handling sites will need to have 21st century infrastructure that protects air and water quality, and they will have to be good neighbors.  The aeration system for the pilot project cost less than $15,000 per zone, which is pretty affordable considering a new diesel windrow turner would likely set you back half a mil.  

    Solar panel prices keep coming down, and efficiency is still going up, so it looks like solar-powered aerated static piles are a good option for community-sized compost sites, and probably could be scaled up quite large.  Already, several compost operators are looking at adopting this technology.  

    The full report on the project can be found linked to the very bottom of this page:

    –Robert Horowitz
    Robert Horowitz is a Supervising Environmental Scientist at CalRecycle.

    Posted on In the Loop by Robert Horowitz on May 23, 2016