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Biosolids are the nutrient-rich organic product of wastewater treatment - a never ending resource. Biosolids return valuable nutrients and carbon to the land. Experience shows that biosolids enrich soils and keep them productive and healthy!

King County's Loop® biosolids are recycled as a soil conditioner in agriculture and forestry, and a portion of our biosolids is composted by a private company and sold as GroCo compost for use in landscaping and gardening.