The loading facility is very unusual as it is a completely circular siding. We would ordinarily expect to see a balloon loop at such a facility or perhaps a conventional loop. Effectively for train working purposes this is a single ended siding because there is only one junction of the siding to the main line. There is no loop within the siding itself. Trains must enter and leave the siding in the same configuration as there is no ability for locomotives to be changed from one end of the train to the other.
A train coming up from Christchurch which needs to turn around and go back to Christchurch would either go first to Ikamatua railway station 1.5 km further north, run around there, return to the siding and propel its wagons in for loading, or enter directly, propel out after loading and then carry on to Ikamatua to run around. In either case additional staff would have to be on hand apart from the train driver for these shunting operations. That is why a balloon loop would have been a more logical design as the train would be turned right around and extra staff and shunting operations would not be needed. Another option for loading is a train coming to Christchurch from Reefton or Ngakawau where other mines load coal onto the rail. But the train would still have to be propelled in even if it didn’t need to turn around, so shunting crew would still be needed. It may well be the case that additional staff are needed for the loading operation as it is a kind of shunt, so maybe that is not the issue it seems.
Here is the map of the sidings overlaid on Google Earth.
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To see this map you must have the Google Earth Plugin installed in your browser. If you don’t have this you might need to install it. Here is the same map in Google Maps, but you won’t be able to see the sidings because Google Maps doesn’t have the latest Google Earth coverage.
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