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We have investigated the terahertz electrodynamics of single crystals of the Ruddlesden-Popper ruthenate Ca₃Ru₂O₇ using optical-pump terahertz-probe spectroscopy. This correlated semimetal orders antiferromagnetically at T_N= 56 K, with the opening of a pseudogap (~2 THz) at T_C = 48 K. We predict that Ca₃Ru₂O₇ exhibits novel non-equilibrium states, with the possibility that excitation of c-axis apical oxygen phonons could result in novel phases absent from the equilibrium phase diagram. In the present study, we have investigated near-IR changes in the THz reflectivity following near-infrared excitation. We observe clear signatures of pseudogap dynamics in the spectrally resolved dynamics. In this presentation, we will present a detailed account of these dynamics along with an update of the phonon driven electrodynamic response.