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We present the first results from a study of OVI absorption around galaxies at z~1 using data from a near-infrared grism spectroscopic Hubble Space Telescope Large Program, the Quasar Sightline and Galaxy Evolution (QSAGE) survey. Based on the WFC3 grism, the galaxy sample is Ha flux limited (f(Ha)>2x10^-17 erg/s/cm^2) at 0.68z1M_odot/yr star-forming galaxies within 2Rvir show no associated OVI absorption to a limit of at least N(OVI)=10^13.9/cm^2. That we detect OVI at such large distances from galaxies and that a significant fraction of star-forming galaxies show no detectable OVI absorption disfavours outflows from ongoing star-formation as the primary medium traced by these absorbers. Instead, by combining our own low and high redshift data with existing samples, we find tentative evidence for many strong (N(OVI)>10^{14}/cm^2) OVI absorption systems to be associated with M\star~10^9.5-10Modot mass galaxies (Mhalo~10^{11.5-12}Modot dark matter halos), and infer that they may be tracing predominantly collisionally ionised gas within the halos of such galaxies.