... reduction .51 .72 .51 ()[]()[]= - - =072 0 100072 0 0 59 © 2003 by CRC Press LLC Water and Wastewater Math Operations To operate a waterworks and/ or a wastewater treatment plant, and to ... the wastewater is 5 ft deep.FIGURE 4 .5 Rectangular tank. (From Spellman, F.R., Spell-man’s Standard Handbook for Wastewater Operators, Vol.1–3, Technomic Publ., Lancaster, PA, 1999.) 50 ft8 ... 12):=¥= 58 8 75 7 48440 3 85 33 ,ft gal ftgalvrHrftftvf=¥¥====¥ ¥=¥ ¥==()3142 25 212 5 314 1 25 100314 156 25 100314 156 25 49 062 5 223.. .,,.Diameter 49 062 5 1...