Problem: The McDonald’s restaurant in Chesaning, Michigan, utilized an ATU system followed by a sand filter and leach bed. After more than a decade of high-strength restaurant load, the leachfield and sand filter both failed.

Solution: SludgeHammer used the existing tanks. The modular bioreactor works in any type of tank, so clearing out the previous system components could give them a new lease on life. Sloan Septic conducted the renovation, pulling out the old equipment and rerouting some of the plumbing to create a sequential flow pattern. Sloan installed six S-86 aerobic bacterial generators and seven supplemental Medusa air diffusers for extra digestion, given the heavy organic loads. A few repairs on the zone valves in the leachfield completed the project. 

Result: The system was restarted with an inoculation of SludgeHammer Blend facultative culture to see if biomat could be cleared out of the sand filter and leachfield. Some zone-switching allowed the system to work from day one, while the sand filter and rest of the field were biologically cleared. Now the system is fully functional and BOD testing showed an effluent strength of just 140 mg/L BOD, more than a 90% reduction. 231-348-5866; www.sludgehammer.net