My point is that in completing a Risk Assessment you look to both reduce the risk of an incident and to reduce the consequence from that incident if it does occur.i have neve seen any assessment completely remove the risk of an incident so you work on then reducing the effect.if you are very near the sea ,as this was,it seems a reduction in consequences would be made by going over the sea as against over land. In the event of the option of being over the sea not available , then you look to perform over the area in the locality that would have the least effect in the event of an incident occurring.i would not consider the option of holding the event over a major highway would be the best option available in most areas. In the final consideration it may be that the overall risks can not be reduced to an acceptable level , so you move to a more suitable location.
I would hate to see this used as a reason to ban these events,but the safety of the non parcipitating public must be a major consideration.i consider the spectators at the event carry out their own opinion of the risk when attending.
The level of risk acceptable ,I would think would a matter to agreed with the authority and the HSE.
You can not carry out any operation without having some element of risk,but you should always look to use means to reduce the effects of that incident.
