Just been looking at my van underneath the sliding door, put a wire wheel in my cordless drill and started removing some surface rust to see what the underlying steel was like, there was a few that were very thin and went through as I brushed it.
But then I noticed some soil in the hole. I poked it with a screwdriver and some more came out, then made a long scraper thing with a zip-tie and look what came out...
I went round the other side and pushed my desert locating tool into the front most drain hole...
There wasn't really any in the rear sections as far as I could see, so I'm guessing this dirt was pushed up the drain holes from the front wheels.
I'll carry on tomorrow and see if I can find any more...

But then I noticed some soil in the hole. I poked it with a screwdriver and some more came out, then made a long scraper thing with a zip-tie and look what came out...

I went round the other side and pushed my desert locating tool into the front most drain hole...

There wasn't really any in the rear sections as far as I could see, so I'm guessing this dirt was pushed up the drain holes from the front wheels.
I'll carry on tomorrow and see if I can find any more...