Kemi cardboard mill is founded on the alluvial bed of Kemi River at the north Easton coast of Botnic Gulf in Northern Finland. The alluvium consists of sandy and silty layers underlain by thick medium dens silty moraine layer. The first cardboard machine, having a belt width of 7.4 m, was constructed in 1972 on 7.5 to 9.5 m long wedge-shaped precast driven piles. Because of the excessive differential settlements and sometimes unexpected dynamic malfunctioning of the machine it was decided to strengthen the foundation before installing the partly new machine and increasing the running speed from 500 to 750 m/min. Piling was done under extremely strict limitations concerning space, vibrations, settlements, dust etc. Extra vertical support was made by using 23...25 long x-form steel piles driven by a compressed air pile hammer down to rock. The piles were held together with old piles by a concrete frame with diagonals, which made the total system - machine - foundation frame, piles and ground - rigid enough to avoid resonance during dynamic loading.