This paper shows application potential of H-jointed steel pipe sheet piles (SPSPs) and H-H joints on vertical cuttoff barriers used in coastal landfills. The authors have developed a number of technologies such as developing the H-jointed SPSPs and H-H joints for SPSP joint sections aimed at improving performance and widening application areas of SPSPs. Hydraulic conductivity of the H-jointed SPSPs with H-H joints was evaluated by experimental studies. In addition, a new construction technique is proposed for vertical cuttoff barriers in which H-jointed SPSPs with H-H joint is applied. The technique uses soil-cement columns to make pile driving easy and simultaneously improves the soil around and underneath the foundation of the structure.