Is the embankment going on top of the soft saturated soil? Are you worried about settlement or slope stability? If the deposit is from an old lake then likely normally consolidated clays which will increase in strength with time as consolidates. Slow, staged construction so that pore pressure...
SLIDE is a great program that has a good interface for performing limit equilibrium analyses. The files from SLIDE can also be used in PHASE2 where finite element slope stability can be completed. Finite element slope stability is good but has not replaced limit equilibrium by a long shot...
