The wastewater lagoons in the Town of Kindersley were badly in need of an upgrade.

The lagoons were outdated and in a poor state of maintenance, and the rural Saskatchewan community of 5,000 was growing.

By May 2020, Con-Tech General Contractors of Saskatoon had been hired to add a few lagoon cells to the existing systems. The company also built a lift station and laid new underground piping along with other upgrades to accommodate lagoon restructuring. The project also included cleaning of the lagoons.

Lagoons are typically cleaned by mechanical desludging and dredging, a costly and often difficult process. Seeking an alternative, Larry Plett, president and CEO of Con-Tech, proposed EBS-Di, a new microbial treatment being developed by EnBiorganic Technologies. He saw it as a chance to review the technology’s performance in an actual field test.

The technology performed successfully and ultimately was adopted by the town to help maintain the lagoons and the wastewater collection system for the long term.

Delicate process

Lagoon discharge regulations are becoming more stringent in Saskatchewan, and many communities are upgrading their lagoon capacities to treat wastewater more effectively.

Lagoon cleaning can be tricky, according to Plett, as there is a risk of damaging the clay liner when mechanically removing material. Because operators cannot readily see the exact position of the dredge head relative to the liner as they work, they leave a margin of safety. That prevents complete removal of accumulated biosolids. In addition, the removed material must be disposed of safely to avoid health and environmental threats.

The EBS-Di system is a remotely monitored, autonomous microbial generator that creates massive concentrations of soil bacteria in an active and adapted format and dispenses them to digest the biosolids. The microbes are designed to work 10 times faster than standard inactive, spore-state microbes on the market, according to the manufacturer.

In time, the generated bacteria will establish a thin biofilm throughout the wastewater collection system, improving its overall performance and health. The microbes work by outcompeting and eliminating pathogens and  other harmful microbes because the proprietary microbe collection is selected to work synergistically. They thrive in the same conditions as harmful microbes, eliminating odors and harmful gases like hydrogen sulfide.

On trial

“The engineers were great about it,” Plett says. “They were definitely interested in what the EBS-Di could potentially do, and they understood how the technology was intended to work. So they were open to trying it.”

A trial of an EBS-Di unit was set up at the lagoon. Con-Tech sectioned off a portion of a lagoon containing the effluent and biosolids to be treated. The 8-by-40-foot container was placed at the north end of the lagoon with its floor and roof removed. This allowed the container to settle to the clay liner while the top remained open for equipment access and observations. Con-Tech estimated that 8,500 gallons of liquid and biosolids were contained.

On May 27, an EBS-Di unit was placed in a small mobile equipment building provided by Con-Tech, positioned about 60 feet from the contained section. The unit operated for 10 days, delivering about 600 gallons of active microbiology into the container.

The Saskatchewan Research Council was engaged as a third party to perform independent testing of the sample progression collected by Con-Tech. Sample testing measured total solids E. coli and coliform bacteria, conventional metrics used in similar projects.

Also measured was microcystin, a toxin produced by cyanobacteria (blue-green algae); because the process can eliminate microcystin from lagoons, it also applicable to lakes, ponds and other water bodies that struggle with harmful algae blooms.

Positive outcome

The microbiology formulation, delivered in a high concentration, eliminated 67.5% of total solids during the 10-day trial, giving a glimpse of what the process could do and showing the capability to eliminate the highly toxic microcystin.

The performance trial proved the effectiveness of the technology as a less intrusive alternative to traditional lagoon remediation. “We made an alternate proposal to use EBS-Di, based on its performance in reduction of total solids,” Plett says. “We did it on a prorated basis, so they would only pay a unit price relative to what was accomplished. They liked our proposal, which could have reduced their expenses significantly.”

However, changing the entire course of contracted work already several months in progress, to the tune of about $1.5 million less, was too much risk. The traditional lagoon cleaning process moved forward, and a local newspaper article warned residents to expect nearly two months of foul odors around the plant while the work took place.

Maintenance application

In a review presentation to the Kindersley Town Council, the project consulting engineer from AECOM Canada recommended the EnBiorganic process using the EBS-Di for ongoing maintenance of the wastewater collection system and the lagoons. The council approved the use of two units for those purposes.

The units will be deployed in two lift stations, within the town and in a new station beside the lagoons. These will remove the biomass buildup in the collection system, take care of the biosolids left behind from the mechanical lagoon cleaning and maintain the health of the collection system and lagoons going forward.

Plett observes, “This capital expenditure for traditional methods created a partial cleaning of the lagoons in excess of $2 million. If you compare that to the $150,000 annual cost to have a couple EBS-Di units, it doesn’t take much effort to make a case for the value of the EBS-Di.”