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WINDSOR -- The surge and strength of wastewater from winemaking vexes vintners in sensitive environmental areas such as the North Coast, but a treatment system going into a multimillion-dollar boutique winery nearing completion in this Sonoma County town might provide a solution not only for wineries but also for homebuilders, rural homeowners and mariners.

The pavement around the DuMol winery at 1400 American Way in Windsor conceals an unconventional septic system and underground drip-irrigation loop designed by Bill Wilson, a water and wastewater expert with Carlile Macy of Santa Rosa. The system features an aerobic microbial inoculator generator made by a company started by Sebastopol-based Dan Wickham, Ph.D., a former Bodega Bay marine biologist.

Dr. Wickham’s SludgeHammer compact cylindrical chambers use low-wattage air pumps to propagate a proprietary cast of oxygen-loving, effluent-eating bacteria. The units were installed in DuMol’s conventional concrete septic tanks in early August.

“We make it so DuMol will not have to pay a sewer surcharge to the town of Windsor,” he said, noting the added cost for high-strength winery process wastewater can amount to tens of thousands of dollars a year. “And if we can get the water quality sufficient enough to use in subsurface drip irrigation, it will not go to the sewer at all.”

Wastewater from washing presses, tanks and barrels lacks the pathogens found in domestic sewage. However, grape skins, juice and other organic matter give winery wastewater high levels of biological organic demand and total suspended solids that complicate municipal treatment plant operation and worry water-quality regulators. That has led to a string of new approaches to wastewater pretreatment for discharge to sewer systems or reduction in the size of or need for treatment ponds on land that could be more profitable growing grapes.

The SludgeHammer system, now being produced and licensed by the SludgeHammer Group in Michigan, grew out of innovations from a group of North Coast wastewater experts working to remediate apple processing wastewater discharges to the Laguna de Santa Rosa from the Barlow Co. apple processing plant in Sebastopol. Using a bacterial blend called IOF500 originally developed to clean up petroleum spills, the inventors developed a compact septic retrofit system called the Pirana.

Today the inventors have gone their separate ways and tweaked the design to different applications and markets. SludgeHammer has found a niche market in providing port-side treatment for hundreds of rooms in large floating hotels, called “floatels,” for petroleum companies.

Bob Rawson, general manager of the Graton municipal treatment plant and a wastewater technology instructor at Santa Rosa Junior College, and partner Victor Harvey added perforated golf tubes to the interior of the chamber to mimic the long-standard trickling filter arrangement for self-flushing sludge.

They’ve licensed their adaptation, called the White Knight, in the North Coast to Septic Skeptic, run by former The Sea Ranch septic operator Russ Hayter, and nationwide to Knight Treatment Systems of New York.

Another original partner, Jerry Fife, licensed Pirana technology as AquaWorks.

None of these systems so far have achieved certification by NSF International, which local agencies look to when approving advanced treatment units for failed septic systems, according to Tom Bruursema, general manager of the Michigan-based organization’s water and wastewater treatment unit programs.

A benefit of the original Pirana design is that it can cost a fraction of activated sludge or other microbial systems and requires little annual maintenance.

Dr. Wickham and Mr. Rawson said they are pursuing NSF certifications that would allow for greater use in fixing failed rural septic systems. Mr. Bruursema said NSF is working toward a standard for evaluating systems such as Pirana derivatives that claim to take care of the clogged leach field problem. The challenge is that the entire system would need to be evaluated, rather than just a unit or component, Mr. Bruursema noted.

The wine industry also could benefit from aerobic bacterial digestion of sludge buildup in treatment ponds, according to Mr. Rawson. A donated White Knight unit has reduced the depth of 35 years’ worth of sludge buildup at the Graton plant by 36 percent this year, reducing the amount needed to be trucked to the Redwood Landfill for use as cover soil.