Construction of the sump required earth retention to protect adjacent plant facilities. The system consisted of internally-braced sheet piles designed and installed by HBI. The elevation of the floor was located about 24 ft below the existing grade, which was to be excavated. The concrete sump floor was to be poured prior to helical pile installation. Due to difficult access constraints, the installation method was limited to working from the existing grade. Also, an existing clarifier tank adjacent to the new sump limited HBI's access around the sump. The location of all new and retrofit pipe support locations was located along a busy corridor within the plant, limiting the helical pile section, drive motor, and excavator sizes.

A combination of helical piles and sheet piles allowed for the construction of the sump. The project team worked with the general contractor and engineers to provide an alternate solution that met the original design load requirements. Hayward Baker completed work in restricted access conditions safely and on time.

Source: Petrochemical Sump and Pipe Support Project