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AUG- 9-99 MON 8: 14 AM 7-H TECHNICAL SVC GRP FAX NO. 0302732290 P. 3 A previous report on this project set the unit flows at 150 gallons per day per connection. This is less than half of the actual or realistic unit flow assignment for this type of development. This proposal would not consider a flow rate assignment of 150 gallons per day per connection. Wastewater Characteristics: In addition to the flow assignments that address the volume of flow, the other major considerations that affects the treatment decisions of the wastewater treatment systems are the wastewater characteristics. That is, the strength of the waste and the nutrient concentration of the waste, (nitrogen compounds). The strength of the wastewater is measured by two (2) criteria, 1)BOD (Biochemical Oxygen Demand), and, 2) TSS (Total Suspended Solids). The nutrient concentration of the raw waste is measured as"total nitrogen"(Kjeldahl plus Nitrate Nitrogen). It is expected that the BOD TSS, and Total Nitrogen values for the proposed development are at the average values for residential waste strengths. Therefore, the following wastewater characteristics are utilized for this project; J10D Concentration 250 mg/1 TSS Concentration 225 mg/1 Total Nitro en Concentration 45 mg/1 ISSUES: The BOD and TSS concentrations expected in the raw wastewater for this development are not a concern. They can be readily treated and reduced to acceptable levels required for specific effluent disposal. The real issue relative to wastewater effluent disposal is the concentration of Nitrate Nitrogen, after all the nitrogen compounds have been converted to nitrate nitrogen. The EPA and State of California standards require that ground water not be elevated over 10 mg/1 of nitrate nitrogen or 45 mgll as NO3 ion. The authors of this proposal have a preponderance of experience in dealing with nitrogen requirements and their reduction. 7-H is under contract with the Town of Paradise and is the Onsite Sanitary Official. We regulate over 10,000 individual waste treatment systems (septic tanks and absorption fields)including small(up to 20,000 gallon per day) wastewater treatment plants including nitrogen reduction. We work hand in hand with Mr. Ron Dykstra, Senior Engineer with the Central Valley Regional Water Quality Control Board in the regulation of systems and the protection of ground water. In doing so we apply the Hantzche-Finnemore Equation for the prediction of elevated nitrate nitrogen in ground water for development and private projects. Similar to the San Joauquin Department of Environmental Health the Town of Paradise is concerned about nitrate nitrogen in their ground water. However background nitrate(NO3) in ground water in Paradise is less than 2 mg/1 as opposed to 30 mg/l in the proposed development 2