Localised event but for something bigger it's no where near far enough for anything but a small business.
You also don't need human intervention either Mother Nature is more than happy to wreak havoc as often as it likes. I proposed a large Earthquake centred close to a major population centre would be catastrophic to that population centre and the infrastructure supporting it. Something as simple as an earthquake and a dam within a couple of hundred miles of the city could be a total disaster particularly if the dam was to go during the earthquake or shortly afterwards.
You could also have an earthquake underwater and then you only have a few hours at best to remove everything from the path of the resulting Tsunami which could decimate an entire coast line and like the Boxing Day one a year or so ago would just wash over any small islands in its path.
Then you can have Human Error like at the
3 Mile Island incident which turned out OK but if it hadn't of then there would have been a major problem in the surrounding area.
Currently the Governments have us all focused on
Terror Attacks so most of us have forgotten about
Natural Disasters or Acts of God. Any of these events are far more likely than a terrorist attack.
Here it really depends on how far away things need to be in the event of some major incident occurring and how big the business actually is as if everyone where killed or injured during one of the above events about the only interested party that would be left is the
Tax Man who would want the necessary forms filled out and it wouldn't matter if everyone had died the paper work still needs to be done.

Col