  Using the Very Long Baseline Array, we observed the active galactic nucleus
(AGN) in NGC 3079 over a span of six months to test for variability in the two
main parsec-scale radio components, $A$ and $B$, which lie on either side of
the AGN. We found evidence for positional differences in the positions of $A$
and $B$ over the six months consistent with the apparent motion of these
components extrapolated from older archival data, finding that their projected
rate of separation, $(0.040\pm0.003)$ c, has remained constant since $\sim2004$
when a slowdown concurrent with a dramatic brightening of source $A$ occurred.
This behavior is consistent with an interaction of source $A$ with the
interstellar medium (ISM), as has previously been suggested in the literature.
We calculated the amount of mechanical feedback on the ISM for both the
scenario in which $A$ is an expulsion of material from the central engine and
the scenario in which $A$ is a shock front produced by a relativistic jet, the
latter of which is favored by several lines of evidence we discuss. We find
that the cumulative mechanical feedback on the ISM is between $2 \times
10^{44}$ erg to $1 \times 10^{48}$ erg for the expulsion scenario or between
$3\times 10^{50}$ erg to $1 \times 10^{52}$ erg for the jet scenario.
Integrated over the volume-complete FRAMEx sample, our results imply that
jet-mode mechanical feedback plays a negligible role in the energetics of AGNs
in the local universe.
