Client Biosolids Composting Needs:

The Environmental Protection Agency regulations categorize biosolids as Class A or B, depending on the level of bacteria remaining in the material after being treated at a wastewater plant. Class A biosolids can be applied as a fertilizer without any pathogen-related restrictions, whereas for Class B biosolids there are buffer requirements, public access and crop harvesting restrictions.

When Sedalia’s Water Pollution Control Department experienced difficulties in maintaining a Class B biosolid rating at two of the city’s three wastewater treatment plants they researched their options and found correcting the issues from the treatment plants would cost the City upward of $4 million. “If we don’t hit that Class B number, our choices are to find another process to do that or put it in the landfill,” Public Works Director Bill Beck said. “It’s not economical to (send it to the landfill), and it’s just wrong anyway.”

ECS Biosolids Composting Solution:

Sedalia researched a number of Class A biosolids management options (lime stabilization, incineration, drying etc) and chose composting as their preferred process solution. City officials approved development of a $1.5 million facility that would compost the wastewater biosolids along with their yard waste to produce a Class A biosolids compost.

Sedalia issued an RFP for compost technology and selected ECS to provide a negatively aerated static pile compost system with automated aeration control and monitoring (CompTroller) and, the CompDog, above grade aeration floor. This solution enables the operator to track when a batch has achieved PFRP, and helps automate optimized process conditions for efficient municipal composting.

The Sedalia facility has operated without issues since 2010. In 2021 ECS upgraded the CompTroller software for preventative maintenance. Dennis Arnold, Chief Operator at the Sedalia compost site since 2018, mentioned that prior to his present position he knew almost nothing about composting. When asked to summarize his experience with the ECS system he said, “…there are no problems…it just works.”