07-25-2018 Septic Design - Laserfiche WebLink

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Comments: tions: = = enter data = adjust if desired = = computer calculated - DO NOT CHANGE! =bedroom Type L�J Residential System 750 GPD design flow Yes Garbage disposal or pumped to septic 50% larger tank with multiple comp/tanks 2250 Gal Septic tank (code minimum) 2500 Gal Septic tank (design size / LUG req'd) Tank options: Multiple tanks or compartments req'd 1.2 GPD/ft2 mound sand loading rate contour loading rate of F2 req's a min r 62.5 ft. long rockbed 10.0 ft rockbed width b2.5 ft rockbed length 3.0 ft Lateral spacing 3.0 ft perforation spacing (maximum of 3 for both) end feed manifold connection laterals F 60.5 feet long 21.0 perfs / lateral 63 perfs total (112 a pert means the first pert starts at the middle feed manifold) 1 /4" inch perfs at =feet residual head gives 0.74 gpm flow rate per perforation for this perf size l3 spacing, 8 pipe size on line 12, max perfs/lateral = 25 line #8 must be less o) 4.0 doses per day ( 4 minimum) 1) 188 gallons per dose (treatment volume) 2.00 5x 12)200 inch diameter laterals must be used to meet "4x pipe volume" requirement 2.00 3x 131 100 Teet of 2.fl inch supply line leads to 17 Igattons of drainback volume (Tip: "top feed" manifold to control the drainback) 14) 205 gallons TOTAL pump out volume (treatment + drainback) i5) 12 feet vertical lift from pump to mound laterals, leads to a: t6) 1 47 JGPM =feet of head, Pump requirement (note: >50gpm may require an extra 3-6' of head) 17i 750 gal Dose tank (code minimum) 1250 gal Dose tank (design size / LUG req'd) at 23.00 gpi leads to a 18) F 8.9 inch swing on Demand float, or timed dosing of4.4 min ON (confirm pump rate with drawdown (this delivers Average flow, =70% of Peak design flow) 9 hrs OFF test and adjust as necessary) 19) 16 inches from bottom of tank to "Pump OFF' float 20) 25 inches from bottom of tank to "Pump ON" float, or1inches to "Timer ON" float if time dosed 2i) 28 inches from bottom of tank to "Hi Level' float, or F38qinches to "Hi Level" float if time dosed 606 gallons reserve capacity (after High Level Alarm is activated) 0.45 gpd/ft2 Absorption area Soil Loading Rate, which gives a mound ratio of F 2.7 (minimum) (this must match the soil boring log) desired mound ratio r 2.7 percent site slope (0-20% range) F8 (% downslope site slope, if different than upslope) 20 inches, or 1.7 ft. to Redox or other limiting condition (need at least 12" to be a Type I) Treatment zone contains=0 inches of 0% soil credit, and =0 inches of 50% soil credit. Giving a: --]inch, or 1.3 ft. Sand Lift Mound CRITICAL FOR FUTURE CERT1FICATIONSHI 27.0 ft.Total ABSORPTION width (with sand beyond rockbed as follows:)