Police said the driver was found "safe and well" between two large landslips along the coastline, about 30kms south of Kaikoura on SH1 between Birches Road and Hundalee Road.
"The driver was to be flown out and the truck was to be left there," a police spokesman said.
However, the spokesman wasn't able to ascertain if the rescue had gone ahead as planned.
Johnson said she first realised her partner of almost 18 years, and father of her two children Fleur, 13, and Chloe, 11, might have gotten caught up in the natural disaster when she woke up at 6am.
While she'd woken up to the rolling motion of the 7.5 magnitude quake just after midnight, it wasn't until later in the morning that she realised Kaikoura had also been rattled.
Her first thoughts; "Who do I get hold of? How do I get hold of someone?"
With the communication lines overloaded it was a "couple of hours of ringing and ringing" before she was able to get through, Johnson said.
She spent the rest of the morning and early afternoon just waiting in her lounge, with her two girls and a number of other friends and family.
"Every time the phone rings, of course, I was jumping for it," she said. "I was just hoping there was some news."
When she finally got the call, from one of the office ladies, she broke down.
"It was relief, complete relief," Johnson said. "I just want to give him a big hug and not let him go for a while."
Dunn's boss, Shane Pearson, was the one who got the call from his employee to say he was safe.
"He's going to get told off, because he rung me instead of her [his partner] first."
He said getting the call from his employee was "better than winning lotto".
However, Pearson said there was little time to discuss specifics.
All he knew was that Dunn, who has been a truck driver for more than 25 years, was safe and well, but it was unclear where exactly the driver was or what had happened.
"He's on the side of the road, his phone was going flat, so we couldn't talk for longer," Pearson said. "He was right in the middle of it ... he was hysterical, he said he was right amongst it.
"We don't know how bad it is, but he's alive, that's the main thing."
Police said communications in the area had been difficult throughout the day, which made it hard to get information.
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