Embodiments of the invention relate to methods of modeling leaching behavior of a polycrystalline diamond (“PCD”) material used in leached polycrystalline diamond compacts (“PDCs”) and methods of monitoring leaching of a PCD material. In an embodiment, a method of modeling leaching behavior is disclosed. A PCD table is provided, which includes a plurality of bonded diamond grains defining a plurality of interstitial regions in which a metallic material is disposed. The PCD table is leached with a leaching agent to at least partially remove the metallic material from the PCD table. A leach depth of the PCD table is determined. A concentration of at least one constituent of the leaching agent is also determined. The leach depth is correlated with the concentration of the at least one metal to generate the model of leaching behavior.