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A. WASTEWATER FLOW PROJECTIONS AND CHARACTERISTICS WASTEWATER FLOW VOLUME PROJECTIONS A number of variables are involved in estimating wastewater Average Daily Flows (ADF) from the final expansion plans for the Southwinds Church project and correlating them with nitrate loading and design considerations. Wastewater flow volume projections for facilities in unsewered areas of San Joaquin County have been historically and typically calculated under one or more of the following guidelines: 1. Data published in the San Joaquin County Sewage Standards. 2. Total number of fixtures serving the Southwinds Church, leading to calculated use per capita. 3.Anticipated maximum number of known on-site people. 4. Historical wastewater flow data from the Church. 5.Number of parking spaces. 6. Data published in the scientific literature. Of the six flow volume determination guidelines listed above, the first three are applicable for this project. The San Joaquin County Sewage Standards assigns 10 gallons per person for a Church with a kitchen, and 5 gallons per person for a Church without a kitchen. These are exorbitant flow volume values and are based on antiquated plumbing fixtures that possessed high water usage volumes. In addition, the Sewage Standards assign 150 gallons per toilet fixture/day, which is typically taken to incorporate urinals, sinks and drinking fountains. This is also an extreme flow volume given contemporary low flow fixtures. The attached Church Demographics and Fixture Unit Count Document found in Attachment B and Appendix B, illustrates the data used to calculate average daily flows (ADF) for the design and nitrate loading portions of this project. The disposal system must be designed to accept the maximum daily flow of any day of the week even though other days of the week may have lower flow volumes. Given that a theoretical maximum number of Parishioners on any Sunday is expected to total 1,105, the following flow volumes are deduced from the data presented: If we assign a value of 75%of all Parishioner categories (i.e.,adults, children) use the restrooms, and each parishioner is assigned 2.0 gallons (1.5 gallons per flush plus 0.5 gallon wash water),we find a conservative wastewater flow volume of: 1,105 Sunday Parishioners x 75%= 829 people x 2.0 gals/person= 1,658 (say 1,700) maximum gals/Sunday. This usage factor also incorporates special events such as potlucks. As a nitrate loading safety factor, this value will be used in the loading calculations as an Average Daily Flow(ADF) for each day of the week, but will be reduced to 25%of this flow value (1,700 gals)to a value of 425 gpd for the remaining days of the week. ANTICIPATED WASTEWATER CHARACTERISTICS The characteristics of the wastewater flow will be black water from toilets and gray water from S, and dishwasher water. Food preparation may occur in the existing Multipurpose Building Kitchenette and the new Worship Center Kitchenette. It is imperative that all food and food by- product wastes are handled as solid wastes and not be disposed of into the septic system. 9 Chesney Consulting