[floxy]

>Some go on for years it seems.

Isn't some of that due to earth settling that you can't really speed up? I remember a fun fact from many years ago where I was growing up. They built a new interstate bridge/overpass, and it wasn't too long after that they noticed it starting to sink. Well it turns out they had drilled sample cores down to like 100 feet, and had good results, but after the sinking, they drilled new cores, and there was a layer of sandstone or something at like 105 feet. I don't really remember how it all got sorted out, but it was under construction for a long time.

[swores]

I wonder (and maybe someone here will know) whether that means they were foolishly cutting corners and should have sampled further than 100ft down, or if what they did was considered best practise and they were just unlucky to find themselves in a freak situation?

[bombcar]

Likely the second - they usually base drilling depth on the known area and a wide margin, so everyone probably thought 75 feet was fine, do a hundred to be safe.

[swores]

Thanks