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Inspection Report 12 August 2005 Windmill Cove Marina San Joaquin County system is reported as having 1,000 linear-ft. The marina system leach field size was unknown at the time of our visit. Using similar numbers as the RV park, the hydraulic loading from the marina residents would be 1,480 gallons per day needing 740 linear ft of leach line. From the description provided of the leach field and its location, it would appear that the designated area would not support the estimated linear feet of leach line necessary. However, supposing that the required leach line were installed at the identified location there would not be any set back from the river. Note this hydraulic evaluation is intended to be a quick overview of the current resident population described to us by the Windmill Cove Marina representative and does not address additional loading from holiday and or special event traffic. The treatment capacity is of the most concern for each leach field system. Septic tanks are primary treatment and in order for a septic system to complete treatment to acceptable levels prior to discharge to waters of the state, a five-log reduction in pathogens and filtering of other pollutants is needed. In order to get a five-log reduction for pathogen removal, filtration and aerobic bacterial predation from unsaturated soils are necessary. To complete the wastewater treatment, one should have at a very minimum one foot of dry soil per log reduction (this is described in the 1972 Regional Water Board Guidelines for Waste Disposal from Land Developments). To comply with the guidelines, each septic system leach field needs to have five feet of separation between highest groundwater and the bottom of the leaching trench. Standard leach field construction requires a total of five feet, at least one foot of soil over the trench and four feet of trench below the distribution pipe. Thus standard construction requires a minimum of 10 feet of soil above highest groundwater. The marina's leach field area is estimated as having a total of five feet of dry soil above high water mark and the RV system's leach field area has about two feet. Since the marina system has an estimated five feet of dry soil this leaves zero feet of separation between the high water mark and the bottom of the leaching trench. The RV system is even more precarious. It is estimated as having approximately two feet of dry land above the high water mark. Standard leach field construction would then set the bottom of the trench three feet into the high water mark. Therefore both systems are discharging septic water (primary effluent) directly into waters of the state. Another issue would be the set backs from the San Joaquin River. Both systems have zero set back on at least one side of the leach field and the marina system may have zero set back on both sides of the leach field. The 1972 Regional Water Board guidelines stipulate 100-foot set back from a flowing stream, however this is an estuary environment, which is quiescent and more like a lake or reservoir and the guidelines state that a 200-foot set back is required for lake or reservoir.