Not that dumb. In a Ward Labs report Ca, Mg, Cl, Na, K are in mg/L as the ion. Sulfate is in mg/L as Sulfur. Nitrite and Nitrate are mg/L as Nitrogen and what OP calls CaCO3 is alkalinity which is in units of ppm as Calcium carbonate. For Ca, Mg, Cl, and Na and K the mg/L number is the number of mg of the ion found in 1 litre of water. For all the others you must multiply by a scaling factor.