Queensland Rail CEO Nick Easy said most of the repairs between Richmond and Nonda in the east and Quarrels and Tibarri in the west had been completed in the past week, reopening these sections to maintenance and ballast trains.

Recovery efforts are now honing in on the final 55 kilometre section of outstanding track damage between Nonda and Quarrels, including the construction of a rail deviation at Nelia.

"Our crews have now recovered approximately 245 of the 300 kilometres of damaged track and are focussed on the final closure zone - the 55-kilometre section between Nonda and Quarrels," Mr Easy said.

"Only minor resurfacing work is required on neighbouring sections from Richmond and Nonda in the east and Quarrels and Tibarri in the west.

"Work is progressing steadily on the remaining 55 kilometres of damaged track, which will be the most challenging repair location to date, given it was the most flood affected.

"The 55 kilometre stretch also includes the site at Nelia, where our crews are in the final stages of completing a rail deviation around the Nelia site where a Pacific National train was inundated by flood waters.

"Completion of repairs to the neighbouring sections have allowed a ballast train to access the site on Wednesday 3 April.

"This deviation will allow freight and passenger trains to resume through Nelia between late April and mid-May, allowing environmental remediation works to continue at the site.

"Pacific National has now been able to remove all 81 wagons and are continuing works to remove their locomotive.

"Due to remaining wet and unstable ground conditions on site, purpose-built matts have supported two cranes throughout the removal of wagons and loco off the tracks.

"With just one sixth of works remaining, we are confident that we will be able to reopen the entirety of the Mount Isa line between late-April and mid-May 2019 as planned."