Mixing cargo on tankers

I once worked for Cleanaway as a “Chempac” chemist.
My tanker driver called me one day as he had a part load of caustic soda on, and his next job was collecting PVA glue. He didn’t want to have to tip the caustic first and as far as I was concerned it was fine, off you go…(obviously it wasn’t really my call).

About five hours later I get a call from Technical Control telling me I need to get up to Pitsea landfill NOW (about 4pm on a Friday, so a run from Southampton to Essex was going to be fun). When I finally arrived, I’m trooped out to the tip face to the tanker and the back door is swung open - and I’m confronted with a 15 tonne, translucent white jelly, slowly wobbling in the sunset! I’m handed a pick axe and a shovel, and am left to get on with it.