  We present optical and near-IR Integral Field Unit (IFU) and ALMA band 6
observations of the nearby dual Active Galactic Nuclei (AGN) Mrk 463. At a
distance of 210 Mpc, and a nuclear separation of $\sim$4 kpc, Mrk 463 is an
excellent laboratory to study the gas dynamics, star formation processes and
supermassive black hole (SMBH) accretion in a late-stage gas-rich major galaxy
merger. The IFU observations reveal a complex morphology, including tidal
tails, star-forming clumps, and emission line regions. The optical data, which
map the full extent of the merger, show evidence for a biconical outflow and
material outflowing at $>$600 km s$^{-1}$, both associated with the Mrk 463E
nucleus, together with large scale gradients likely related to the ongoing
galaxy merger. We further find an emission line region $\sim$11 kpc south of
Mrk 463E that is consistent with being photoionized by an AGN. Compared to the
current AGN luminosity, the energy budget of the cloud implies a luminosity
drop in Mrk 463E by a factor 3-20 over the last 40,000 years. The ALMA
observations of $^{12}$CO(2-1) and adjacent 1mm continuum reveal the presence
of $\sim$10$^{9}$M$_\odot$ in molecular gas in the system. The molecular gas
shows velocity gradients of $\sim$800 km/s and $\sim$400 km/s around the Mrk
463E and 463W nuclei, respectively. We conclude that in this system the infall
of $\sim$100s $M_\odot$/yr of molecular gas is in rough balance with the
removal of ionized gas by a biconical outflow being fueled by a relatively
small, $<$0.01% of accretion onto each SMBH.
