MARQUETTE — A contractor hauling treated dewatered biosolids used as a soil amendment out to a field in Little Lake had a spill just outside the treatment plant on U.S. 41 Thursday morning, Mark O’Neill, director of Municipal Utilities, reported.

In a written statement, O’Neill said the truck’s tailgate was not properly secured and an estimated four cubic yards of biosolids spilled. A front end loader and tractor with a brush were used to collect the biosolids. A city street sweeper was then used for final clean up.

No waterway was impacted. The Michigan Department of Energy and Great Lakes was notified of the matter.

Biosolids are nutrient-rich organic materials produced by treating sewage sludge from wastewater treatment plants. Through physical, chemical and biological processing, raw sewage is stabilized and sanitized to eliminate disease-causing pathogens, resulting in a safe, soil-like product used heavily in agriculture and landscaping.