This year marks the 20th anniversary of a Midwest car factory that achieved zero waste to landfill. What started as a directive to Subaru of Indiana Automotive Inc. (SIA) from its parent corporation overseas has evolved into a mindset and a culture that permeates throughout the plant. 

But in 2002, when no one had heard of the concept much less executed it, SIA was put on a journey without a road map and given five years to get there––to even their own surprise, the factory accomplished zero-landfill status two-and-a-half years later. As of 2023, SIA has zero landfill certification from Green Circle, which involved an initial rigorous nine-month investigation; they will be recertified annually and every three years will undergo a more intense process. 

SIA Environmental Compliance and Energy Manager Monica Klaas, who’s been with the company about one year, says one of her predecessors, Denise Coogan––who helped choreograph the companywide endeavor––relied on management at all levels to provide continuous communication both internally with employees and downstream with suppliers. Very quickly, Coogan also launched an initiative to invite employee ideas and engagement.  
With no template or best practices to follow, the staff champion took the reins to craft first steps and set an achievable priority. Step 1 was literally a “dumpster dive,” said Klaas. They needed to identify every waste type and its source.

“They didn’t have the data that they needed. But there weren’t really nice, neat steps—it was sort of a hard push as they were just trying to figure out how to tackle this very large problem,” she said.  

“If you think about it, when all of your stuff is going out the door to a single solution—to a landfill—you don’t worry too much about what’s going in the dumpster. But when you have to start picking out one waste stream from another and looking at what you’re actually disposing, you need to have an overall data picture of what the facility produces as waste. It was a different mindset than what they had done before.”

To move forward with clear focus, the company chose first to go after the biggest volume of its industrial waste streams: production packaging waste from its myriad parts suppliers. To solve the massive output of landfill garbage at the point of assembly, Subaru worked with suppliers to move to 100% reusable packaging––meaning plastic, Styrofoam, wood, and even some metal, depending on the incoming parts. SIA eventually partnered with a company specialized in by-product management to streamline removing packaging away from the assembly line work area, then collapsing, stacking, and sorting containers to be returned back to suppliers. 

Subaru uses color-coded containers throughout the factory, including in breakrooms and offices. They also focus on minimizing contamination of waste to make it attractive to recyclers.

In 2004, the plant had reduced its waste per vehicle by 55%. In 2024, they’ve reduced the waste per vehicle by over 95%. 

“The progress is really phenomenal,” said Klaas, “and we’ve continued the momentum through the years with new annual goals. We challenge our associates to look at what they do every day and see if there’s a way to make it more efficient or produce less waste. We ask for their ideas regularly, because that’s where our best stuff comes from.”

What Can a Foundry Do?

When it comes to environmental initiatives, the biggest undertaking is actually managing the program, according to KERAMIDA Senior Project Engineer Kayla Gibbons, and as the saying goes, you can’t manage what you can’t measure. “You need to go in there and actually figure out what you’re putting in each container and if that waste should be separated or put together. But actually knowing what you’re producing and how much––that’s crucial to managing any program.

“After that,” she continued, “you really need to treat your waste as a product. That’s where a lot of people get hung up in their managing practices––not treating their waste streams as an actual, sellable or reusable product. They just think of it as garbage and don’t manage it.”

Implementing a committed, all-hands-on-deck recycling program is an effective way for foundries to make large strides for the earth and their bottom line. But, as Gibbons advises, it’s important to protect your recycled commodity from contamination––in other words, keep it separate from real trash.

During a session at the AFS EHS Conference in October, which Gibbons and Klaas co-presented on the subject of zero-landfill mindset, Gibbons outlined four major areas where foundries can take a big dent out of the garbage heap.

1) Sand–the most widely reused byproduct in the foundry industry.
Potential opportunities for use in:
Asphalt pavement ingredient
Structural fill and road base
Sub-base for an airport runway
Manufactured potting soil
Daily cover for landfill
Cement manufacturing
Gravel pit––highwall reclamation
Masonry mortar mixes

2) Slag 
Potential opportunities for use in:
Metal recovery
Structural fill
Coarse aggregates
Gravel Pit – highwall reclamation
Cement mix

3) Refractory 
Potential opportunities for use in:
Road base at landfill
Metal recovery

4) Baghouse Dust
Potential opportunities for use in:
Asphalt seal coating
Kitty litter
Polymer composites
Metal recovery (grinding)
Clay recover (sand system)

5) Filters 
Potential opportunities:
Filter bags––metal recovery and waste to energy
HEPA filters––metal recovery

Gibbons adds that state by state, regulatory parameters can vary, so it’s important to talk to local agencies about your potential project and obtain proper approvals. And for each project, foundries should be prepared to allocate resources to document and keep appropriate records. Recycling isn’t a one-size-fits-all deal, so be prepared to do your homework to understand your company’s waste streams as well as the local market needs for recycled commodities.