In December of 1930, the first “mud jack” job took place in Burlington, Iowa. A State Highway Commission Mechanic by the name of John W Poulter had designed a machine that would pump a slurry mix of dirt, water and portland cement through small drilled holes in the concrete using hydraulic pressure. This would raise the slab of cement and fill any voids of soil that caused the cement to sink. Mudjacking is still the fastest and most effective concrete leveling and lifting method today.