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raAMIC HEAD (TDH) ot be determined at this time since other design factors are unknown,particularly 7an chamber to the mound system. Consequently, an estimate of the TDH is provideof 185 feet from the dosing chamber to the end distribution network for the prim DH the pump must work against: System network head= 1.3 (conv. factor)x distal pressure 5 ft=6.5 ft Elevation distance between the pump and the highest elevation of the distribution network=10.0 ft Friction loss in force main =7 ft(185 ft of force main+manifold)+add-on friction loss of 5 ft= TDH - 10+5 + 7 +5 +4= 31 ft ZP PRE UIREMENTS p p system, each pump pumping 5 gpm a ainsti3l feet of hea . After final building design, wbich will j iclude septic tanks/dosing cham er ound s�ste�n�hon,then the actual pump can be sef6cteWased on the System Performance Curve. DOSE VOLUME - A dose volume of-20% of design flow( gal/d ADF) shall be used=75 gallons. This conforms with the California State Water Resources Control Board- Guidelines focthe Design. Installation and Operations of Mound Sewage Disposal Sy stems documef" commended dosing volumes" found in Section 34.0, Page 17, Table C for a two bedroom house. U 10 ti es the lateral void volume: Lateral dia. = 1.0 in. Lateral length= 31.5 ft Number of laterals=6 Lateral void volume=0.041 gal/ft Net Dose Volume=5 x 31.5 x 6 x 0.041 =77 gals/dose. Floats shall be set to dose an approximate volume of75'gals/dose By having orifices in the 12 o'clock position with shields,the pumps will not have to charge the piping network at the time of every dose. E. MONITORING Two inspection ports or observation tubes shall be installed within the mound system to observe the sand filter-effluent interfaceTor effluent ponding. The tubes are to be"inverted tees" and be 4 in. PVC. It is imperative that 1/8 inch screens are on each open end of the tube and that pea gravel rip-rap is placed in front of the screens to prevent infiltration from the sand filter. V.,,"C�NCLUSIONS, RECOMMENDATIONS AND MAINTENANCE t SSS§ 5g. The soils underlying the proposed mound system disposal area for the new People of Chris hurch show acceptable permeability that can be considered exceptional for the short-term. the long-term acceptance rate, the permeability of the soils will no doubt slow based on the / numerous factors described in this report. These include historical evidence based on repairs/ replacements/additions,biomat formation, groundwater table influences and the unknown characteristics of the wastewater. 19 Chesney Consulting