gas-liquid-equilibrium-ph-of-groundwater-supply

Hello,

I have a question I am stuck on. Question is as follows:

A groundwater supply is initially at pH 8.0 and contains 2*10^-3 eq/L alkalinity. If the alkalinity is all attributable to the carbonate system, determine whether the water is under-saturated or supersaturated with respect to atmospheric CO₂

I dont have any more information regarding the question, just information given in this question.

Thank you for helping me.