Planting Plutonium

My parents had a very long garden that backed on to some allotments. My father was quite territorial about the garden, and when he heard that planning permission had been requested to build a housing estate there, started hatching a plan. Most people would write to the council with their objections, but my father decided that a more effective way to deal with the threat would be to bury some plutonium at the bottom of the garden. He said this would stop anyone building anything there for a very long time indeed. What was worrying about this was that a)he could probably have got hold of some plutonium through his work and b) if it was too dangerous for other people to live near it, what about us in the house? Fortunately the petrol crisis intervened, and he became more concerned about burying petrol cans in the garden. I don't know whether anyone dug them up again after the crisis ended; any avid gardeners living there now will have a bit of a surprise one day.