A sample of mine water has 100 mg/L of $Ca^{2+}$ and 10 mg/L of $Mg^{2+}$. The equivalent weights of $Ca^{2+}$ and $Mg^{2+}$ are 20 mg/meq and 12.2 mg/meq respectively. The hardness of mine water in unit of mg/L as CaCO$_3$ is ______.