Method and means for sand reblending

A method of reblending aggregate includes delivering aggregate of various sizes to the classification tank having a plurality of stations with primary and secondary discharge valves. The tank is then calibrated to determine raw feed analysis, discharge rates and the flow multipliers needed to develop a mathematical model of the tank. Inputting the calibration information data and the desired production specification into a computer allows the tank to be operated and controlled with appropriate adjustments in discharge rates and valve percent settings at each station. This method provides more accurate control than the existing min-max control methods. The apparatus for this method includes the tank, a pumping device, and a computer interconnected with a PLC and electrohydraulic mechanisms for valves at each tank station such that both the discharge rate from each station and the valve percent settings of the individual valves at each station are variable and controllable.