County looks for septage treatment solutions

by Michael Howell

Ravalli County took a significant step forward last week in addressing the problem of how to properly dispose of the ever-growing amount of septic tank septage produced in the county when it hired Morrison-Maierle to produce a Septage Treatment and Biosolids Composting Facility Preliminary Engineering Report (PER). 

For many years, Ravalli County septic pumpers have both land-applied and hauled septage to the City of Missoula Resource Recovery Facility, which is the only consistent partner for pumpers that don’t have land application sites. 

In 2022, the City of Missoula received over 2.5 million gallons of septage. The two largest haulers were from Ravalli County. Eckert’s Patriot Pumpers and Bitterroot Valley Septic delivered 756,267 and 662,665 gallons of septage, respectively, to the City of Missoula’s Resource Recovery Facility. But septage waste poses significant challenges for municipal wastewater treatment and resource recovery facilities as nutrient loading of septage influent can be 25 times stronger or greater than municipal wastewater influent.

The sh-t hit the fan, you might say, in 2023, when the City of Missoula completed a once-in-twenty-years cleaning of its wastewater primary digester and decided to greatly reduce the amount of septage it would accept from out-of-county pumpers. It was clear during this time that permitted septage land application sites were not abundant in Ravalli County and posed their own sanitary hazards. In response, a wastewater working group was formed to look for some solutions. 

It soon became apparent that none of the Ravalli County municipalities or sewer districts can fully accept the anticipated septage loading from Ravalli County. Stevensville and Hamilton may have similar concerns as those of the City of Missoula, as septage loading has upset VFA/Alkalinity ratios in the digester process. Additionally, the nutrient loading of pure and even pretreated septage may be of significant concern to groundwater discharging sewer districts like Corvallis and Victor.

That’s when the Ravalli County Economic Development stepped in and applied for some grant money to obtain a PER to review septage demands, liquid treatment alternatives, biosolids treatment alternatives, and identification of future funding sources.  

Morrison-Maierle stated in its RFQ that the county is dedicated to exploring alternatives that are, first, aware of potential partnering with public wastewater treatment facilities, and secondarily, that impacts of septage may not be feasible for a single existing public facility. The company encourages the consideration of a central screening and pretreatment facility providing initial treatment of septage and then transport and dispersal of pretreated liquid streams to multiple public wastewater treatment partners.

“When Ravalli County kicks off this project, there are few carbon copy examples in the region,” stated Project Manager Aaron McConkey. “Our planning process is open minded and will listen to stakeholders throughout the process to ensure alternatives presented can be implemented successfully. Discussions with pumpers and end use operators will be critical along with identification of operational policies/regulations that may be required to make this facility a successful example in the years to come.”

The company provided a detailed timeline for the development of the PER, beginning with a kick-off meeting on August 15, 2024, and including three additional public meetings on December 17, 2024, March 12, 2025 and April 9, 2025, and culminating with a funding application for the final proposal by May 5, 2025.

The wastewater working group still meets and those meetings, held in the County Commissioners administration meeting room, are open to the public. Key members of the group include Commissioner Jeff Burrows, Ravalli County Department of Environmental Health Director John Palacio, and Hamilton Public Works Director Donny Ramer.

“I think this is going to provide a lot of good information for everybody in this county,” said RCEDA Director Julie Foster. “How many septics do we have in Ravalli County? How many gallons of septage are generated annually? What are the land application opportunities now and going forward? What new regulations are we going to see concerning ‘forever chemicals’? Will it be a private company solution or a public works? This PER will give us the information we need to move forward.

“I think we will get this done. We always get things done here, if we don’t give up,” said Foster.