It was November 1963 and Mr Thompson was a construction engineer for the Electrolytic Refinery and Smelting Company of Australia (ER&S) working on what remains the biggest project of his 37-year career.

The world-changing news came in as workers were pouring the concrete foundations of the stack, which would rise 200 metres into the air some 18 months later.

‘‘We’d started early in the morning and the concrete wagons were bringing concrete in – it was the largest single pour of concrete in the Illawarra at the time,’’ Mr Thompson recalled this week.

‘‘One of the cement mixer drivers had the wireless on and he came out about 5am and yelled out over the site ‘President Kennedy has been assassinated’.

‘‘The whole site just stopped. I thought, ‘My goodness, what’s going to happen [in the world] now’. But we continued with the pour.’’

Read more: Boom! The Port Kembla Stack comes down

Now 89, Mr Thompson started work at ER&S straight after his engineering studies in the mid-1940s. He was to stay with them until his retirement in 1984 when, fittingly, he was presented with a copper model of the stack.

Until a decade ago he and wife Joan lived high on the hill at Warrawong, overlooking what his grandchildren and great-grandchildren refer to as ‘‘Pa’s stack’’.

While he concedes that it is time for the stack to go, he won’t be watching its downfall.

‘‘I don’t want to get involved in the ‘fors’ and ‘againsts’. I just want to pay tribute to ER&S who had the courage to spend the money under difficult financial circumstances to build the chimney,’’ he said. 

‘‘The company did honestly believe they were doing the right thing at the time for the area.

‘‘...I’m not going out to see it go down...all that work that went into it, people worked on it every day for two years, slowly going up, up, up. Coming down it’s a bit emotional,’’ he said.

Mr Thompson will still have many fond – and some frightening – memories of working on the stack alongside contractors Tileman &Co.

One afternoon, he said, the fumes from the ER&S 60-metre stack then in use halted work on the emerging stack. It was his job to climb up the inner concrete stack which rose high above the outer concrete shell at that stage of construction.

‘‘The sulphur dioxide was really choking – I started to go up the ladder on the inner chimney and took a breather and looked out over the ocean, and one panel of the safety net was missing.

‘‘...I just froze with panic, I don’t know how long for. The only thing that got me going was the embarrassment of it – ‘Poor old Tommo’ [they’d say] ‘froze to death on the chimney’.’’