RECONSTRUCTION of the retaining wall on Nepean Highway near Olivers Hill in Frankston will take three and a half months. Work started on the $1.4 million wall in February, but it collapsed on Thursday 19 April before it could be finished. Dramatic pictures of the wall collapsing were taken by a man walking his dog. The first wall was built of rocks in steel cages and backfilled with sand. The second attempt is being constructed using steel posts hammered into the ground, horizontal wooden planks and backfilled with lighter material. The lighter material would “reduce the load imposed on it”,…