  The low-energy effective field theory below the electroweak scale (LEFT)
describes the effects at low energies of both the weak interaction and physics
beyond the Standard Model. We study the one-loop renormalization of the LEFT in
the 't Hooft-Veltman scheme, which offers an algebraically consistent
definition of the Levi-Civita symbol and $\gamma_5$ in dimensional
regularization. However, in connection with minimal subtraction this scheme
leads to a spurious breaking of chiral symmetry in intermediate steps of the
calculation. Based on the 't Hooft-Veltman prescription, we define a
renormalization scheme that restores chiral symmetry by including appropriate
finite counterterms. To this end, we extend the physical LEFT operator basis by
a complete set of off-shell and one-loop-evanescent operators and we perform
the renormalization at one loop. We determine the finite counterterms to the
physical parameters that compensate both the insertions of evanescent
operators, as well as the chiral-symmetry-breaking terms from the
renormalizable part of the Lagrangian in $D$ dimensions. Our results can be
applied in next-to-leading-log calculations in the 't Hooft-Veltman scheme:
using our renormalization scheme instead of pure minimal subtraction separates
the physical sector from the unphysical evanescent sector and leads to results
that are manifestly free of spurious chiral-symmetry-breaking terms.
