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III. NITRATE LOADING STUDY FINDINGS A. WASTEWATER FLOW VOLUME PROJECTIONS AND CHARACTERISTICS Wastewater Flow Volume Projection In accordance with EHD requirements,the Nitrate Loading Study must quantify the total number of people(employees,customers, etc.)who will be on the subject Parcel, whether full-time, or partial- time (e.g., truck drivers)who may use the toilet/sink, etc. on a daily basis. Several variables are involved in estimating wastewater flows from a facility. Wastewater flow volume projections for facilities in unsewered areas have been historically and typically calculated under numerous guidelines and scenarios, as illustrated in the following list: 1. Published Data in the San Joaquin County Sewage Standards and scientific literature. 2. Number of bathroom fixtures(bathroom use per capita)for a facility. 3. Number of parking spaces for a facility. 4. Maximum number of people(i.e., employees, customers, etc.)for a facility. 5. Historical wastewater flow data from an existing facility. 1. The San Joaquin County Sewage Standards assigns 15 gallons per person for Industrial Buildings with no food cafeteria, 10 gallons per vehicle served for service stations,or 30 gallons per person for day workers at offices. 2. The number of bathroom fixtures is unknown at this time. The Sewage Standards assign 150 gallons per toilet fixture(employee/public use). The most applicable criteria is assigning 15 gallons per person for an Industrial/Commercial Building. It is known from Mr. Powell that there will be a maximum of 31 employees, which includes office personnel, truck drivers and mechanics. Approximately twenty one of these employees will be truck drivers. Customers are anticipated to be minimal at two per day for a total of 33 people on-site daily. The EHD allows a reduction of the 15 gals/person/day for transient workers such as truck drivers down to 5 gals/person/day. But as a safety factor, the 15 gals/person/day will remain to demonstrate that even with this incorporated safety factor,the nitrate loading calculations, the calculated septic tank capacity and the calculated filter bed size all comply with EHD requirements. Wastewater Flow Characteristics There will be no food preparation in the office building, only a break room. Therefore, concentrated organic loading will not exist. Other characteristics of the wastewater flow will be predominately blackwater from toilets and graywater from sinks. Additional wastewater constituents may consist of other liquids to the system, such as coffee and juices. No industrial or commercial chemicals, solvents, petroleum hydrocarbons, etc. should be introduced into the wastewater treatment system. This is critically important given the nature of the American Crane Rental business proposed to occupy the subject property. Wastewater from the washing of trucks will be captured by a"closed-loop" system to be designed by Provost & Pritchard Consulting Group as the project proceeds. 7