  We present the spatially resolved H-alpha (Ha) dynamics of sixteen
star-forming galaxies at z~0.81 using the new KMOS multi-object integral field
spectrograph on the ESO VLT. These galaxies were selected using 1.18 um
narrow-band imaging from the 10 deg^2 CFHT-HiZELS survey of the SA22hr field,
are found in a ~4Mpc over-density of Ha emitters and likely reside in a
group/intermediate environment, but not a cluster. We confirm and identify a
rich group of star-forming galaxies at z=0.813+-0.003, with thirteen galaxies
within 1000 km/s of each other, and 7 within a diameter of 3Mpc. All our
galaxies are "typical" star-forming galaxies at their redshift, 0.8+-0.4
SFR*(z=0.8), spanning a range of specific star formation rate of sSFR=0.2-1.1
Gyr^-1 and have a median metallicity very close to solar of
12+log(O/H)=8.62+-0.06. We measure the spatially resolved Ha dynamics of the
galaxies in our sample and show that thirteen out of sixteen galaxies can be
described by rotating disks and use the data to derive inclination corrected
rotation speeds of 50-275 km/s. The fraction of disks within our sample is
75+-8, consistent with previous results based on HST morphologies of Ha
selected galaxies at z~1 and confirming that disks dominate the star formation
rate density at z~1. Our Ha galaxies are well fitted by the z~1-2 Tully-Fisher
relation, confirming the evolution seen in the zero-point. Apart from having,
on average, higher stellar masses and lower sSFRs, our group galaxies at
z=0.813 present the same mass-metallicity and TF relation as z~1 field
galaxies, and are all disk galaxies.
