  We give the {\it spectral decomposition} of the path space of the
$U_q(\hatsl)$ vertex model with respect to the local energy functions. The
result suggests the hidden Yangian module structure on the $\hatsl$ level $l$
integrable modules, which is consistent with the earlier work [1] in the level
one case. Also we prove the fermionic character formula of the $\hatsl$ level
$l$ integrable representations in consequence.
