It had all the more emotional impact on him as he was standing with his little grandson trainspotting on the West Coast main line at Thankerton when the sighting occurred last Tuesday night.
Villager William McLaughlin said: “At around 6.30pm, we spotted a train travelling south towards us.
“As the train drew closer to us, it became apparent what the cargo consisted of.
“I could see two large white metal box-like containers carried on two low-loader wagons, a powerful diesel at the front pulling, and another at the back pushing. As it passed us, the reality of what we were witnessing sent a chill down my spine.
“The white containers were carrying highly-radioactive plutonium.
“Before reaching us, the train had travelled through some of the most populated areas in Scotland with its nuclear cargo, including Wishaw, Carluke, Lanark, Thankerton and Symington.
“The consequences of an accident impacting on the population of Scotland, involving these two containers, is the stuff of nightmares.
“As they passed us, the driver tooted his horn as if it was a family day out.
“The transit of these cargoes through Scotland by either rail or road continues unabated and is unacceptable.
“Scotland is currently powerless to act to stop this madness.
‘‘No doubt some people will think that such a train is just fine and dandy, but I don’t take my grandson trainspotting to watch nuclear madness passing us on the main line between Scotland and England.”
Clydesdale MSP Aileen Campbell commented: “This would have been understandably alarming for the constituents involved.
“Many people who live alongside the railways in Clydesdale will be concerned to have potentially nuclear material moving so close to their homes.
‘‘This comes on top of the transportation of nuclear warheads on the M74 in poor conditions last winter.
“I am keen to know what safety precautions are in place and what measures there are to protect residents in the case of any accident.
‘‘I will be contacting the Scottish and Westminster governments to try to ascertain what material is being transported through the constituency .”