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The equivalent width of the associated \MgII\ absorption line system in 3C\,205 ($z=1.534$) has decreased by at least a factor of $2$ (at 95\% confidence) in 0.7\,years (rest frame). This variability strongly suggests that the absorbing material is physically associated with the quasar. We use the variability timescale and ionization modeling to constrain the density and nuclear distance of the absorbing gas clouds. These results are compared to similar calculations for other radio-loud and radio-quiet quasars with associated absorption systems. We also discuss the general interpretation of radio-loud quasars with associated low-ionization absorption, an unusual number of which have very red colors and/or high optical polarization. The possibilities for the absorbing material include cluster galaxies, intracluster material, and material intrinsic to the quasar. We propose a model of intrinsic absorption in which there is a dusty disk of moderate optical depth surrounding the nucleus, and the absorption arises in outflowing equatorial material.
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