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We use medium- and high-resolution spectroscopy of close pairs of quasars toanalyze the circumgalactic medium (CGM) surrounding 32 damped Ly$\alpha$absorption systems (DLAs). The primary quasar sightline in each pair probes anintervening DLA in the redshift range $1.6<z_\text{abs}<3.5$, such that thesecondary sightline probes absorption from Ly$\alpha$ and a large suite ofmetal-line transitions (including $~\rm OI$, $~\rm CII$, $~\rm CIV$, $~\rmSiII$, and $~\rm SiIV$) in the DLA host galaxy's CGM at transverse distances$24\ \text{kpc}\le R_\bot\le284~\rm kpc$. Analysis of Ly$\alpha$ in the CGMsightlines shows an anti-correlation between $R_\bot$ and $~\rm HI$ columndensity ($N_\text{HI}$) with 99.8$\%$ confidence, similar to that observedaround luminous galaxies. The incidences of $~\rm CII$ and $~\rm SiII$ with$N>10^{13}~\rm cm^{-2}$ within 100 kpc of DLAs are larger by $2\sigma$ thanthose measured in the CGM of Lyman break galaxies (C$_f(N_\text{CII})>0.89$ andC$_f(N_\text{SiII})=0.75_{-0.17}^{+0.12}$). Metallicity constraints derivedfrom ionic ratios for nine CGM systems with negligible ionization correctionsand $N_\text{HI}>10^{18.5}~\rm cm^{-2}$ show a significant degree of scatter(with metallicities/limits across the range $-2.06\lesssim\logZ/Z_{\odot}\lesssim-0.75$), suggesting inhomogeneity in the metal distributionin these environments. Velocity widths of $\text{CIV}\lambda1548$ andlow-ionization metal species in the DLA vs. CGM sightlines are strongly($>2\sigma$) correlated, suggesting they trace the potential well of the hosthalo over $R_\bot\lesssim300$ kpc scales. At the same time, velocity centroidsfor $\text{CIV}\lambda1548$ differ in DLA vs. CGM sightlines by $>100~\rm km\s^{-1}$ for $\sim50\%$ of velocity components, but few components havevelocities that would exceed the escape velocity assuming dark matter hosthalos of $\ge10^{12}M_\odot$.

On the Metallicities and Kinematics of the Circumgalactic Media of Damped Ly$\alpha$ Systems at $z \sim 2.5$