  We investigate the Lyman alpha line transfer in nearby and high redshift
starbursting galaxies, where the effect of high optical depths and the role of
dust in the scattering medium are expected to be conspicuous and should be
treated in a very careful manner. We present our first results in dustless,
static, and uniform HI media with moderate Lyman alpha line center optical
depths \tau_0=10^{3-6}. We assume that the temperatures of media to be
T=10^{1-4}K, and use a Monte Carlo technique. We investigate the basic
processes of the line transfer and confirm the criterion of a\tau_0>10^3 for
the validity of diffusion approximation suggested by Neufeld in 1990, where $a$
is the Voigt parameter. Adopting the model suggested by Tenorio-Tagle et al.,
we performed calculations on the Lyman alpha line formation for each
evolutionary stage of an expanding supershell. The emergent Lyman alpha
profiles are characterized by the double peaks and the absorption trough at the
line center. We found that the absorption troughs expected in most of the
evolutionary stages are not wide enough to be observed with current
instruments. However, the absorption trough in the Lyman alpha emission profile
from an expanding recombining supershell can be marginally detected.
