  In this article, we consider a Branching Random Walk (BRW) on the real line
where the underlying genealogical structure is given through a supercritical
branching process in i.i.d. environment and satisfies Kesten-Stigum condition.
The displacements coming from the same parent are assumed to have jointly
regularly varying tails. Conditioned on the survival of the underlying
genealogical tree, we prove that the appropriately normalized (depends on the
expected size of the $n$-th generation given the environment) maximum among
positions at the $n$-th generation converges weakly to a scale-mixture of
Frech\'{e}t random variable. Furthermore, we derive the weak limit of the
extremal processes composed of appropriately scaled positions at the $n$-th
generation and show that the limit point process is a member of the randomly
scaled scale-decorated Poisson point processes (SScDPPP). Hence, an analog of
the predictions by Brunet and Derrida (2011) holds.
