With fire brigades from Dannevirke, Norsewood and Ormondville, along with the FENZ command vehicle from Hawke's Bay, personnel from St John from throughout the region and the Palmerston North Rescue Helicopter taking part, the exercise was "bigger than Ben Hur", participants said.
"We are using the scenario as a training opportunity, for our rail incident controllers, (RIC)," Jeff Tremain, KiwiRail's zero harm adviser, said.
"We do exercises throughout the country for RIC, including tunnel and terminal scenarios."
Mr Tremain met with Mr Kendrick three times over the past month to identify risks and hazards associated with such a major exercise.
"That's why we arranged with Higgins, through the NZTA, to reduce speed on the adjacent State Highway 2," he said. "They have effective controls in place, including closing a passing lane for motorists safety."
For Mr Kendrick, the exercise had taken a lot to put together.
"My stress will be over when the day is over," he said. "But something like this never goes as you think."
Terence Ahern, the Norsewood fire chief, operations manager for the exercise, said the event had been a real learning curve.
"Knowing how all the systems work has been crucial," he said.
And while this was just an exercise, everyone involved were reminded next time it could be real.
* More in Saturday's Dannevirke News.