To save on the use of new ballast, its transport and the associated considerable cost, the existing ballast was first cleaned and treated. The recyclable components were refitted while the spoil that was no longer usable was removed by the MFS units and deposited away from the track in Horneburg. The PM 1000 URM carried out the cleaning and recycling of the ballast as well as the installation of a formation protective layer. Depending on the quality of the existing track bed, the machine enables up to 100 percent of the track bed material to be reused and it can also respond to different load capacities of the subgrade. It was mostly not necessary to fit geotextile fabric because, after compaction, the 30 cm thick formation protective layer FPL already ensured the required load-bearing values despite the nearby marshland. It became obvious that 135 years ago people knew very well where to lay the track.
With three excavating chains the PM 1000 URM is as fast as it is thorough in excavating the existing material at any required width and depth. In the forward direction of working, the excavated material is transported to the ballast recycling, screening and washing wagon. The spoil for disposal is conveyed on belts to the construction train of MFS units coupled on to the front. The new material for the formation protective layer and to top up the ballast is simultaneously fed from the rear end of the 52-axle, ten-part PM 1000 consist of wagons. Here it is transport wagons with containers, not MFS units, that form a second construction train. Both construction trains - with spoil at the front and with the material for the FPL and new ballast at the rear - travel to the disposal and loading sites along the line, independently of the PM 1000 URM. To do this they are coupled with main-line diesel locomotives. To shorten the distances, the storage area for new material of the intermediate layer had been set up at a road leading to Dollern level crossing (which was under possession anyway) and protected with a mat. While lorries brought in more material a wheel loader loaded the containers, also known as buckets, in quick succession.
The containers were then transported using two gantry units running at the top of the transport wagons. The rear gantry unit continually brings along two containers whilst the gantry unit running closer to the machine tips one container load at a time into its bunker - either with the material for the FPL or the ballast bed, depending on the requirement. This relay system with container handover shortens the travelling distances of the two gantry units and thus accelerates the processes. The observer can see gantry units constantly moving containers to and fro at the top of the transport wagon throughout the whole working period. Their paths only cross at the respective handover point.
The plate compactors following straight after the intermediate layer installation can avoid any foundations, walls and railings next to the track in variable working width. Once the FPL and ballast have been reinstalled a tamping satellite with lifting and lining unit, which is integrated into the machine, concludes phase 1 of the permanent way reconditioning, with the old track still in place. Construction trains can travel on the track straight away at a remarkable speed of 70 km/h. Overall, the PM 1000 URM achieves a considerable output: At the nearly 5,000 metre long construction sections at Dollern, it was continuously in operation for around 50 hours day and night over the Easter weekend.