The new domestic wastewater system employs two Orenco Advantex AX-100 filtration pods for biological treatment to reduce Biological Oxygen Demand (BOD), suspended solids (SS), nitrogen (N), and bacteria. It does not require certified operator per current State Water Resources Control Board standards, but periodic maintenance is required as a condition of the manufacturer warranty. Monitoring will be required per Sonoma County Operational Permit. The system is not subject to California Title 22 certification because disposal will be made using sub-surface drip technology. No re-use or surface disposal will be employed. Daily flows ranging from 500 to 6,000 GPD will be equalized following the primary septic tank treatment, and prior to the secondary treatment. Design flows for the Advantex AX‑100 pod and sub-surface drip field is 3,500 GPD.
Kitchen wastes are intercepted by an existing concrete in-ground grease interceptor of 1,200 gallons capacity. Maintenance of the interceptor for grease removal will be written into the Operations & Maintenance Manual.
The 10,000 gallon septic tank will be monitored and periodically pumped to remove accumulated sludge as indicated when sludge and scum volume approaches one-third of the tank volume. Sludge will be trucked to an approved disposal facility equipped and permitted to receive septage.
The domestic wastewater system repair will involve the use of electric power. The septic and recirculation/discharge tanks at the Primary and Secondary Treatment Works, respectively, will require electric recirculation and discharge pumps. The advanced technology Advantex AX-100 treatment unit requires an electric fan for active air circulation, and the overall system requires two control / alarm panels. The owner will coordinate with the contractor for electrical service and dedicated telephone communication with the control panels.
Total electrical consumption of these intermittently dosed packed bed filters is much lower than suspended growth aerobic treatment units which require a continuous duty compressor to supply air. Solid state control panels require minimal energy to operate. The air circulation fan consumes minimal energy with a fractional horsepower motor. The flow equalization pumps will consume approximately 2,640 Watt Hours per day (24 doses * 5/60 hrs * 110 V * 12 A). The Advantex pumps, fan, and drip dispersal pumps will each consume a similar amount for a total of less than 10 KWH per day.
Highly treated Advantex effluent will be dispersed to the soil via sub-surface drip irrigation technology in areas separate from any of the vineyards. These areas meet current standards for drip dispersal systems in terms of site slope, soil depth, soil permeability, and setbacks or separation from critical features. Sub-surface drip dispersal technology was selected as the preferred method for several reasons:
- Minimal soil disturbance among the roots of several mature oak trees.
- Optimal dispersal patterns to best utilize the soil mantle.
- Efficient site utilization which would otherwise be limited due to varied slopes.
- Rigid slope limitations among other system types which would otherwise require a different system type for each slope regime or range.
- Minimal soil disturbance allowing better erosion control.
The sub-surface drip dispersal technology is designed and will be installed per current industry best practices. The primary field is subdivided into four zones to allow smaller more serviceable pumps. Duplex pumps are specified for reliability.
Flow meters installed on the discharge pressure main and flush return line will allow measurement of total dispersal volumes minus the backflush volume. A pressure gauge will be installed in the field to sense whether the pumps are delivering adequate flows, and whether a break has occurred in the dispersal lines causing lower pressure than required to disperse effluent evenly over the entire field.