dosing rates for split manifold systems

[juany]

I'm designing a large commercial ossf LPD system on sloping ground (2,780 gpd). I can justify using a split manifold system due to the difference in elevations between the lowest & highest lines which allows each subsystem to be designed separately. But when it comes to determining the dosing rate that will be used in sizing the dosing chamber.. I get stuck. Can anybody shed some light here? I jsut want some help in justifying sizing the dosing chamber for one subsystem with alternating pumps but I'm concerned with undersizing the tank... any help will be appreciated.