them ibc tanks can split ,especially if there a few years old and been out in the sun ,only this week I filled one up with a 1000 litres of heating fuel as the tanker cant get down my track to the house ,I normally get 500 litres because I,m paranoid it will split but this time I thought I would risk it and guess what it split, luckily for me it was right across the top so only lost about ten litres coming down the hill. god I was lucky not to lose the lot, that was on my own land but if one split on a public highway you would need to get the fire brigade to sort that spill outa and you would