I think there is a mistake ...

I think there is a mistake with TDS concetration. It should be 84.000 mg/l, instead of 840.000 mg/l. Acordingto the data, you can use RO because your cl-  goal is not to stright. The hardness is too high, so you will need some preatreatment to reduce the total hardness, such as softening using resins or lime softening. You also have to check the suspended solid concentration to prevent some problems in the RO membranes. Depend of this, the turbidity  and the Silt Density Index (SDI), yo have to choose between Microfiltration or nanofiltration as a pretreatment. Finally, chemical treatment is needed to avoid problems during the RO operation.