The gravel pit, the Małkinia railway station and the regulation of the Bug river were places of very hard labour of prisoners, often resulting in physical exhaustion and death. At present, it is impossible to estimate how many people lost their lives in these works and what benefits the commandant and individual companies using the prisoners had.

As a rule, all newcomers to the camp worked for some time in the gravel pit. The prisoners did the hardest work of extracting gravel and loading it onto wagons, the so-called “cradles”. These wagons were driven on “narrow” tracks and were pulled out of the middle of the gravel pit by a small steam engine. On the ramp gravel was transhipped from cradles to “wide” wagons. From there, the whole transport was transported to the railway station to Treblinka and further to its destination. The work in the gravel pit was very exhausting and after a few weeks the prisoners fell into weakness. Watchmen guarding the prisoners in the gravel pit were cruel. Those unable to work, the sick, the weak, usually died quickly or were killed by SS-officers.

In the gravel pit, the prisoners were not even allowed to look around, as this was considered an attempt to escape. There was also a group of Polish wage workers who were paid for their work. They mainly operated the narrow-gauge railway and transhipped gravel on the ramp.

The prisoners also worked by the nearby Bug river. They worked on erecting floodbanks in the vicinity of Małkinia and on drainage works, which consisted in draining marshy areas.

A group of prisoners worked on a farm producing for the needs of the camp, and located outside the camp, about 500 meters west of the fence, on the so-called Milewek.