Inside the Dimeo Lane Resource Recovery Center, on the ramp of the Food Scrap Pre-Processor, a team of three works to back up a trash truck. It’s a tight fit.
The truck deposits its load into the processor: giant corkscrew-shaped augers shepherd banana peels, avocado skins, and unidentifiable, wet slop to an opening at the end of the tank. The material then moves into a series of chutes and emerges, through a loom-like screen, as a brown mash.
“When you mix all the colors of the rainbow, you get brown. It’s like a brown applesauce,” Leslie O’Malley says, pointing at a window behind which the slurry churns. O’Malley is the City of Santa Cruz’s waste reduction program manager. She is part of the city-wide effort to comply with SB1383, the state bill which works to reduce methane and other short-lived climate pollutants across California.
The Food Scraps Recovery Program, now just shy of a year in operation, responds to the SB1383 mandate that each jurisdiction reduce organic waste by 75% relative to 2014 levels by 2025. This is key in reducing greenhouse gas emissions.
“Methane emissions from landfill and food scraps in a landfill are the third leading contributor to greenhouse gas emissions,” O’Malley explains.
The Gritty Details
As many as 33 to 40 tons of raw food scraps arrive at the facility each week from commercial and residential units of Santa Cruz. After pre-processing, the material continues its journey—in tanks aboard another truck—to Sustainable Organic Solutions in Santa Clara. The material then gets processed into animal feed.
“We are working to dispel this idea that it goes directly from collection to pig slop,” O’Malley says. “It is made into pellets for animal feed—that part gets lost. It goes through further processing. Once it is dehydrated, it becomes additive for parts of pig feed. Other parts of it go to biodiesel and fertilizer.”
While the City of Watsonville mixes food scraps with yard waste in their green bins and trucks the organic material to an industrial composter in Marina, Santa Cruz decided to go for the food-scrap processor. This allows the city to limit the carbon costs of transporting the material.
“If we had [commingled yard waste and food scraps], we would have had to send seven trucks a day to Marina, just to do that part, and then they’d have to come back and collect the recycling and the garbage,” O’Malley explains. With the current system, “Sustainable Organic Solutions comes and gets it about every ten to fourteen days.”
The food scraps processor also allows for an eventual transition to a more local solution—digesting the food scraps in the city’s Wastewater Treatment Facility.
“The Wastewater Treatment Facility is within six to ten miles of this facility. It’s in our own ‘waste-shed’, if you will,” O’Malley says.
The Wastewater Treatment Facility is not ready for the volume of deposits from commercial and residential collections. Consultants are beginning to study what is needed for digesters to handle deposits of the highly acidic food waste and how best to capture energy from the decomposition process.
Challenges
John Lippi, former sanitation supervisor back from retirement to oversee operations at the Resource Recovery Center, has another 51 days—and counting—before his second retirement. Over the 40 years of his career, he has seen many sides of waste management. One big challenge looms.
“We get enough plastic bags with the commercial, so that’s why we insist that the residential people don’t use them,” Lippi says. Plastic bags and compostable bags foul the machinery, getting twisted in the augers and further along in the processing.
While looking at the deposits from the truck, O’Malley points out a compostable bag and an aerosol spray can.
“You know, most people have in their mindset composting, that it’s a composting program, and so they don’t understand, ‘Why can’t I use a compostable bag?’” O’Malley says
The other factor that Lippi manages, beyond contamination, is the upkeep of the motors, cleaning the units, and managing the water content in the mash.
“The system needs some moisture to keep it all moving. [Lippi and his team] have really worked hard to figure out the balance. Sometimes it’s too wet and they have to add drier material,” O’Malley says.
This material is agricultural in origin to maintain the quality of the mash as an eventual animal feed. All inputs into the system must be food-based. That’s why the program can’t accept items like paper towels, coffee filters, or compostable to-go items.
“The good thing about Santa Cruz being vertically integrated is that we are our own public works department. We run the facility. We collect the stuff. We get the opportunity to be more closely connected to it. It is great to be able to come and look at a load and say, ‘John, what are people still confused about? How many bags are you seeing? What do we need to do outreach on?’” O’Malley says.
Every single-family home within the city limits of Santa Cruz received a postcard explaining the system, along with a curbside, six-gallon brown pail for food scraps collection last August. For multi-family residences, the steps are more complicated.
Currently, those living in multi-family residences that number five or more units must contact their property manager who then contacts the city to arrange for counter-top pail collectors and a central food scrap collection can or dumpster. O’Malley has hired additional staff to facilitate enrollment of the more than 400 multi-family residences within Santa Cruz.
“Not everyone is cookie-cutter. Not every multi-family has the same set up of carts. Maybe they’re gonna have a dumpster, maybe they’re gonna have a cart. But the biggest thing for multi-families often and business is the space constraints and the enclosures. We’re working with planning on all these new building projects going up as they’re thinking about their trash rooms.”
Looking Ahead
O’Malley says we won’t know if we are hitting our 75% reduction goal until the next Waste Characterization Study, during which third-party contractors categorize and measure waste in representative trash truck loads. Meeting the goals of SB1383, according to O’Malley, is a big lift. She makes mention of a report on state-wide progress which suggested that we won’t make our targets and the need for re-assessment.
“It’s great legislation and well intentioned. I think it’s just hard. How could they have possibly thought of everything and what it was gonna take to implement it? And back to that report coming out saying, ‘I don’t think we’re gonna make it. We should pause.’ Are you kidding me? We have put in so much energy and we’ve got that momentum going.”
While the Food Scraps Recovery Program is a step in the right direction, O’Malley is very clear on the biggest thing people can do to fight food-waste-related greenhouse gas emissions.
“Prevent it,” O’Malley says.
“I think it’s great that we’re getting organics out of the landfill,” she continues. “But let’s really look at how much food we’re purchasing. Or restaurants are serving, or grocery stores, which are buying to make sure that we have this cornucopia of color at our disposal when we go grocery shopping. People can reframe their relationship to food and not rely on, ‘It’s okay, I put it into the brown pail. Or, ‘I put it into the compost, I didn’t waste it.’ These steps are valuable, but they have to work together, just like those three Rs of Reduce, Reuse, Recycle. It’s gotta be: Reduce, Reuse, and Rot.”
Public Tours Resource Recovery Center, Fridays, June 16-August 25, at 10am and 1pm. Free. 605 Dimeo Lane, Santa Cruz. Pre-registration required.
