Pretreating high-strength waste for orchard and winery

Problem: After one year of careful monitoring by the local county health department and the State Department of Health, it was determined in 2017 that the waste strength loading at Huber’s Orchard and Winery, located in Starlight, Indiana, was too high for the new mound system. An additional pretreatment system was needed to lower the waste strength prior to discharge to the mounds.

Solution: Zoeller Pump Company offered design assistance and components for a new mound system to treat waste from numerous structures. They recommended a recirculating media filter treatment system to be installed between the existing septic tanks and the mound system. The treatment systems are similar to recirculating sand filters, with the main difference being the size of the treatment media, which is typically 3/8-inch diameter pea gravel instead of sand media. Zoeller found after many years of use that 3/8-inch pea gravel does not plug. A local engineer designed the new RMF at 4,000 gpd using a waste strength of approximately 700 mg/L BOD₅, which required a 30-by-30-foot RMF. Commissioning of the RMF was done in October 2019.

Result: After one month, the new RMF was treating wastewater efficiently, meeting the objective of effectively pretreating effluent prior to discharge to the mound system. Samples collected averaged 10.5 mg/L BOD₅ and 2.3 mg/L TSS. 800-928-7867; www.zoeller.com