  SDSS J083942.11+380526.3 ($z=2.315$) is a FeLoBAL quasar that exhibits
visible Balmer absorption lines (H$\alpha$), implying a significant $n=2$
population. The quasar also shows an array of absorption lines, including \oi,
\niii, \feii, \mgii, \aliii\, to \civ\ and \nv. The high-ionization absorption
lines such as \civ\ and \siiv\ are revealed by slightly blueshifted BAL
troughs. The resonance doublets such as \mgii\ and \aliii\ are saturated but
did not reached zero intensity which indicates that the BLR is partially
covered. Overall, however, the absorption is predominantly from low-ionization
\feii\ lines, emitted from ground and excited states up to at least 3.814 eV.
This implies that the absorbing gas spans the hydrogen ionization front and
extends into the partially ionized zone where neutral hydrogen is certainly
present. Notably, the hydrogen line spectrum of the quasar shows no signature
of expected Ly$\alpha$ absorption. Instead, the line spectrum shows an unusual
Ly$\alpha$ emission characterized by a fully filled emission line spectrum
which is a composite of a strong narrow core superposed on a weak broad base.
Taking into account the effect of partial covering to BLR, we have extracted a
strong DLA trough in Ly$\alpha$ emission region. To fit the spectrum, we
performed photoionized model calculations and compared them to the
observations. We found that photoionization modeling using CLOUDY can
successfully reproduce the main characteristics of the quasar spectrum, and the
predicted neutral hydrogen column density arising from the clouds responsible
for the low-ionization absorption provides a good match to the extracted DLA
trough. This indicates that both the DLA and the low-ionization absorption
arise from the same medium that is roughly collocated with the dusty torus.
