A free field representation of the gl(1|1)k current algebra at arbitrary
level k is given in terms of two scalar fields and a symplectic fermion. The
primary fields for all representations are explicitly constructed using the
twist and logarithmic fields in the symplectic fermion sector. A closed
operator algebra is described at integer level k. Using a new super spincharge
separation involving gl(1|1)N and su(N)0, we describe how the
gl(1|1)N current algebra can describe a non-trivial critical point of disordered
Dirac fermions. Local gl(1|1) invariant lagrangians are defined
which generalize the Liouville and sine-Gordon theories. We apply these
new tools to the spin quantum Hall transition and show that it can be
described as a logarithmic perturbation of the osp(2|2)k current algebra
at k = −2.