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We present an HST Cosmic Origins Spectrograph (COS) spectrum of the QSO SDSSJ095109.12+330745.8 ($z_{em} = 0.645$) whose sightline passes through theSMC-like dwarf galaxy UGC 5282 ($M_B = -16.0$, $cz = 1577$ km s$^{-1}$ ), 1.2kpc in projection from the central HII region of the galaxy. Damped Ly$\alpha$(DLA) absorption is detected at the redshift of UGC 5282 with $\log$[$N$(HI)cm$^{-2}\:$] = 20.89$^{+0.12}_{-0.21}\:\:$. Analysis of the accompanying SII,PII and OI metal lines yields a neutral gas metallicity, $Z_{HI}$, of [S/H]$\simeq$ [P/H] $= -0.80\pm0.24$. The metallicity of ionized gas from thecentral HII region, $Z_{HII}\:$, measured from its emission lines is [O/H]$=-0.37\pm0.10$, a difference of $+0.43\pm 0.26$ from $Z_{HI}\:$. This difference$\delta$ is consistent with that seen towards HII regions in other star-forminggalaxies and supports the idea that ionized gas near star forming regions showssystematically higher metallicities than exist in the rest of a galaxy'sneutral interstellar medium (ISM). The positive values of $\delta$ found in UGC5282 (and the other star forming galaxies) is likely due to infalling lowmetallicity gas from the intergalactic medium that mixes with the galaxy's ISMon kpc scales. This model is also consistent with broad Ly$\alpha$ emissiondetected at the bottom of the DLA absorption, offset by $\sim 125$ km s$^{-1}$from the absorption velocity. Models of galaxy evolution that attempt toreplicate population characteristics, such as the mass-metallicity relation,may need to start with a galaxy metallicity represented by $Z_{HI}$ rather thanthat measured traditionally from $Z_{HII}\:$.

Absorption line abundances in the SMC-like galaxy UGC 5282: evidence for ISM dilution from inflows on kiloparsec scales