Complex sentence: Traffic was diverted onto the old A5 route through the Glyn Bends whilst the rock face was made safe, involving the removal of 230,000 tonnes of rock and alluvial deposits.
Split into simpler sentences: Traffic was diverted onto the old A5 route, on a stretch known as the Glyn Bends, whilst the rock face was made safe. This involved the removal of 230,000 tonnes of rock and alluvial deposits.