Condon-Johnson (CJA) & West Coast General joint ventured on this design-build public works project. The city of Chula Vista was in need of a secant pile wall for the purpose of protecting Telegraph Canyon road from the erosion that has been occurring in a nearby creek. The secant pile wall consisted of 30” diameter piles that spanned a length of 770’. Soils had potential for caving and water was present. CJA utilized a dual-head secant pile drilling technique where both the casing and hollow stem auger are simultaneously drilled into the ground and concrete is pumped through auger during tooling withdrawal.