Drilling to China!

Today was our second soil test. Porter Davis perform an indicative preliminary soil test before the demolition of a Knock Down and Rebuild job. This allows them to have some idea of prospective costs. However, a second more complete soil test is performed post demolition to establish a better representation of what really lies beneath our feet.

So we drill to China to find out.

As an aside, our block was also being resurveyed on the same day. I took the time to have a quick chat to the guys and I (as they were) quite surprised to find that the area had not been resurveyed since the original 1950's site establishment surveys! This has happened because it is not mandatory to survey a block of land for a single dwelling, however, it IS mandatory to survey if you are subdividing. Our entire area still has a surviving covenant in place that prohibits subdivisions! So no units in our area, which really adds to the tranquillity of the area!

Back to holes. Porter Davis request six holes to be drilled so that they (or really, the engineers who work out the slab designs) get a better overall picture of what is needed. I was surprised to find out that some other builders only request three holes to be drilled.

So, Ennio arrives with his mobile drilling rig (don't we all need one of these?)

There is a small petrol engine on the back of the truck that powers the hydraulics that allow the drilling rig to be tilted into position, raise and lower the drill bit as well as turn it.

The deepest we got was about 1.7m, indicating no rock there, however, from what we can work out, the soil is mostly clay with basalt floating rocks in it. The bigger those rocks, the more costly it will be to remove them.

With the soil attached to the drill, you can see the soil at different depths. Here it is all mostly clay.

If you were not present when this occurred, all you would see are a couple of these on your block.

Ennio was happy for me to video him and his work, so here is the entire process as a video.