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Abstract This paper investigates the physical conditions of the circumgalactic medium ofL^⋆galaxies through explorations of observed ion tracer gas kinematics and comparisons of observations to different ionization models. For this analysis, we utilize Civobservations from the CIViL^⋆survey (∼0.14 ≤z_gal≤ 0.25) and directly compare them to observations of matched lines of sight from the Cosmic Origins Spectrograph-Halos survey. We find that the kinematic parameters for Civand Oviare likely (>95%) drawn from the same parent distribution, suggesting that these two ions are kinematically coincident andpotentiallyoriginate under the same physical conditions. We find that the measured Civ/Oviand Nv/Oviratios are inconsistent with single-phase equilibrium models. For 70% of the objects in our sample, regions allowed by the column density ratios in the density-temperature space do not overlap, creating a “zone of avoidance.” We also investigate the origins of Civ, Nv, and Oviby exploring a cooling flow model under collisional ionization. We find that both Nvand Oviare consistent with the predictions of the model, but the column densities of Civare ∼2.5 times higher than the predictions. As Civhas a lower ionization energy than Nvand Ovi, it is possible that Civhas contributions from both the warm/hot and cool photoionized phase.