Strickland did not take into account the swampy lowland and high water table that characterizes the terrain around New Orleans, and so during its career the New Orleans Mint building has encountered numerous structural problems from the shifting soil beneath its foundation. In the 1840s the building was reinforced with iron rods inserted between the floors. In 1854, the federal government hired West Point engineering graduate (and Louisiana native) Pierre Gustave Toutant Beauregard to fireproof the building, rebuild the arches supporting the basement ceiling and install masonry flooring. Beauregard completed the work in conjunction with Captain Johnson K. Duncan by 1859. During this period, the Mint's heavy machinery was converted to steam power so a smokestack (since demolished) was built at the rear of the structure to carry away the fumes.