--ABSTRACT: In this paper, the premature failure of a stainless-steel stack from a mining company was analyzed. The stack was manufactured using stainless-steel according to ASTM A312 Type 316L and, after just one year of service, massive leakages and cracks were observed near the welds. After visual examination of the stack, a representative sample was extracted, and it was analyzed using visual and radiographic inspection, metallographic examination and Scanning Electron Microscopy (SEM) coupled with Energy Dispersive Spectrometry (EDS), optical emission spectrometry (OES), ferrite number (FN), and leak testing (LT). The corrosion mechanisms involved were identified, as well as the sequence of events leading to the failure. Two different mechanisms were observed: acid dew-point corrosion caused by condensation of H2SO4 and HCl at the inner walls of the chimney followed by stress-corrosion cracking near the welded joints.