The engines are not total loss any more, so the hot oil doesn't drop out the bottom of the crankcase on to the ground or track. They have to be drained at the end of the meeting and disposed of environmentally.
At Stoke last night Lee Payne went clockwise round the track before the start of a race & went onto the centre green to get around the tapes. Margaret Vardy excluded him, but then let him go of 15mts.