  Lattice QCD allows us to probe the low-lying hadron spectrum in finite-volume
using a basis of single- and multi-hadron interpolating operators. Here we
examine the effect of including tetraquark operators on the spectrum in the
scalar meson sectors containing the $K_0^*(700)$ ($\kappa$) and the $a_0(980)$
in $N_f = 2 + 1$ QCD, with $m_\pi \approx 230$ MeV. Preliminary results of
additional finite-volume states found using tetraquark operators are shown, and
possible implications of these states are discussed.
