The bottom of the retaining wall for the house has had a land drain (perforated pipe), wrapped in geotextile membrane (black sheet material that prevent land drainage systems from clogging with silt and fines by creating a water permeable barrier preventing fines and silt passing but allowing free movement of water into the drainage channels) has been laid down and then covered with gravel.
The same has been done for the retaining wall for the garage, where the back of the wall, that has already had 2 coats of SBR waterproofing painted on, has had the RIW Double Drain sheet secured to the wall. This is so that water coming through the ground, drains down the wall, to the land drain and away, so as to not build up pressure on the wall.
Above is for the house retaining wall.
Below is for the garage retaining wall.
Every 20cm the compactor is run over to keep it all tightly packed in.
They have put some props up on the wall while they are working below this bank. Better safe than sorry.
In the photo below, you can see that some of the garage wall has had the top half filled with concrete.