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The iconic radio galaxy Centaurus A is the nearest example of radio-mode AGN feedback in action. Gas accretion onto the central supermassive black hole has powered multiple cycles of jet- and wind-driven outflows that span 10 orders of magnitude in physics scale from the milli-parsec radio jets and ultra-fast X-ray wind to the mega-parsec scale radio structure. Yet we still do not know if this giant radio structure is affecting the thermodynamic state of the circumgalactic medium (CGM) enough to prevent future star formation in this galaxy comma as predicted by cosmological hydrodynamical simulations of massive galaxies. Here we propose high-S-N COS FUV spectroscopy of four newly catalogued FUV-bright background QSOs with projected distances of 130-150 kpc from Cen A to directly probe the radio structure of Centaurus A for the first time. These data will be combined with archival data of similar quality on QSOs with projected distances of 270-510 kpc (which will be used as control sight lines outside of the radio structure) to probe the covering fraction comma kinematics comma ionization comma relative metallicity comma and multi-phase nature of the CGM using a diverse set of diagnostics (Si II comma Si III comma Si IV comma O I comma and C II). These data will provide new insights into the process of radio-mode feedback and new tests for current and future models.