For nearly 30 years, Soilutions has had one simple philosophy:
Start with clean ingredients.
It's one of the reasons we proudly say that our compost is made from landscape trimmings, sustainable forestry management materials and recycled food waste—not biosolids.
In fact, we've never used biosolids in our 30 years of compost processing.
As more states begin reexamining—or even restricting—the use of biosolids in compost and agriculture, we thought it was a good time to explain what they are, why they're commonly used, and why we made a different choice from the very beginning.
What Are Biosolids?
Biosolids are the nutrient-rich organic solids that remain after municipal wastewater (sewage) has been treated.
After wastewater from homes, businesses, hospitals, and industries is cleaned, the remaining solids are further treated to reduce pathogens and stabilize the material. Once those treatment standards are met, the material is referred to as sludge or biosolids.
Because biosolids contain nitrogen, phosphorus, and organic matter, they've been used for decades in agriculture, land reclamation, landscaping, gardening and as an ingredient in compost products.
Why Are Biosolids Used in Compost?
Composting requires a balance between carbon-rich materials and nitrogen-rich materials.
Carbon comes from materials like wood chips, leaves, and brush.
Nitrogen is needed to feed the microorganisms that drive the composting process.
Many compost manufacturers use biosolids because they're readily available, inexpensive and provide a concentrated source of nitrogen.
At Soilutions, we chose a different path.
Why We Use Food Waste Instead
The only nitrogen-rich ingredient we use is recycled food waste.
Every day, grocery stores, restaurants, food distributors, schools, and other commercial partners generate food that can no longer be sold or consumed.
Rather than sending that material to a landfill where it produces methane, we recycle it into compost.
Food waste provides the nitrogen our composting microbes need while also helping divert thousands of tons of organic material from New Mexico landfills.
It's a win for healthy soils and for the environment.
Doesn't Composting Kill Harmful Organisms?
Yes.
A properly managed composting process reaches temperatures exceeding 140°F, effectively destroying pathogens such as E. coli, Salmonella, and many other disease-causing organisms, along with weed seeds and insect larvae.
That's true whether the nitrogen source is food waste, animal manure or biosolids. The composting process itself is extremely effective at making compost biologically safe.
So Why Avoid Biosolids?
The discussion surrounding biosolids today isn't primarily about pathogens.
It's about contaminants that don't readily break down during composting.
Researchers continue studying substances that may be present in wastewater, including:
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PFAS ("forever chemicals")
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Certain pharmaceuticals
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Hormones
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Personal care product residues
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Other persistent industrial chemicals
Many of these compounds are remarkably stable and can persist through wastewater treatment and composting.
As research has expanded, several states have begun reevaluating or restricting the land application of biosolids because of concerns about these persistent contaminants.
Scientific understanding continues to evolve, but we believe it's always wise to start with the cleanest ingredients possible.
Our Philosophy Hasn't Changed in 30 Years
Long before PFAS became a household term, Soilutions made a simple decision:
Use natural ingredients.
Our compost is made from:
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Wood and slash from sustainable forestry management
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Landscape trimmings
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Recycled food waste
That's it. NO biosolids. NO manure.
Just clean, natural ingredients transformed through a carefully managed composting process into biologically active compost that supports healthy gardens, landscapes, farms, and communities.
Why It Matters
Healthy compost begins with healthy inputs.
By choosing food waste instead of biosolids, we're able to recycle valuable nutrients that would otherwise end up in a landfill while avoiding materials that continue to raise questions among researchers.
It's one more way we stay true to our commitment to producing compost we proudly use in our own gardens—and for you to use in yours.
The Bottom Line
At Soilutions, we've never believed in shortcuts.
For nearly three decades, we've believed that the healthiest soils begin with the cleanest ingredients.
That's why our compost has never contained biosolids.
And it never will.
Healthy soil starts with healthy ingredients.
