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Pump Tank Sizing <br /> Assuming a pump height of 20" and a tank with 125 gallons per inch: <br /> Pump submergence volume =2500 Gallons <br /> Dosing Volume = 715 Gallons <br /> Equalization Volume =2855 Gallons ** <br /> Emergency Storage Volume = 2000 Gallons *(highest daily flow) <br /> Adding the volumes yields a required dosing/equalization tank volume of 8070 <br /> Gallons. <br /> Dosing Regime: 714.5 gallons every 12 hours. Given a measured pump delivery <br /> rate of 62 gpm, the repeat cycle timer would be set at 11.5 minutes "on" and 12 <br /> hours (or 11.8 hours) "off'. <br /> Example#3 (Flea Market): <br /> Assume: A 200-vendor flea market with 25,000 square feet of covered floor <br /> space (120 gpd/1000 sq.ft. of covered floor space). The site has a clay (Group IV) <br /> soil. The flea market operates on Friday, Saturday, and Sunday. <br /> Day Daily Flow <br /> Friday 3000 gallons <br /> Saturday 3000 gallons <br /> Sunday 3000 gallons <br /> Weekly Total: 9000 gallons <br /> Equalization cycle is 1 week(7 days) <br /> Equalized Daily Flow: 9000 gallons/7 days = 1286 gallons/day <br /> The drainfield is sized for a daily waste flow of 1286 GPD. <br /> Trench bottom area is: 1286 gpd/0.3 LTAR=4287 ft2. <br /> Linear footage: 4287 ft2/3 feet wide trenches= 1429 ft. <br /> Dosing Volume: 429 gallons (46% of 4" corrugated drainline capacity) <br /> Flow Balance: <br /> Day In Out Residual <br /> Friday 3000 gal.* 1286 gal. 1714 gal <br /> Saturday 3000 gal. 1286 gal. 3428 gal <br /> Sunday 3000 gal 1286 gal 5142 gal** <br /> Monday 0 1286 gal 3856 gal. <br /> Tuesday 0 1286 gal 2570 gal. <br /> Wednesday 0 1286 gal 1284 gal <br /> Thursday 0 1286 gal 0 gal <br /> Total: 9000 gal. 9002 gal 0 gal <br /> 8 <br /> 108 <br />