The Stillwater-Ngakawau rail line has been closed ever since.
On June 18, Bathurst Resources started trucking coal from its Stockton mine to the former Pike River coal stockpile and load-out facility at Ikamatua, following the collapse.
There are up to 75 truck cycles a day between 7am-7pm.
In an update, KiwiRail South Island regional infrastructure manager Gary Ikin said it had begun assessing the damage by sending drones in to get pictures.
"In the coming days we will be doing further drone work, including scans to check for any movement in the tunnel."
To understand the extent of the damage and scope of repairs required in the 370m-long tunnel, a detailed physical inspection would be required.
"Safety is our priority and we will need to develop a re-entry plan, which then needs to be approved. This work is under way and we will be liaising with WorkSafe NZ on it."
KiwiRail engineers had started working on potential remediation options, which would depend on the outcome of the physical inspections.
At the moment he could not provide a timeframe for when the tunnel could be reopened.
"We appreciate our customers’ patience and understanding, and we are working closely with them to keep their coal moving to Lyttelton.
"Coal is now being road bridged from their mines and being loaded on to our coal trains at Ikamatua and Stillwater."
The Stillwater-Ngakawau line, which carries mostly coal from Stockton to the Port of Lyttelton, remains closed indefinitely. — Greymouth Star
