Libertie and The Mint at the corner of 6th and Bixel in Downtown Los Angeles is a Holland Partner Group project Designed by Togawa Smith Martin and Engineered by Englekirk Structural Engineers.  The excavation for the garage ranged from 18 to 47 feet below grade with 2 to 4 parking levels.  1 to 3 rows of tiebacks were used to brace the soldier piles installed by Malcolm Drilling.  Two sides of the Bixel House property were supported at the deepest location of the project where tiebacks were coordinated beneath, threaded in orthogonal directions.  Once the plan bottom was reached, contaminated soils were discovered and excavation had to proceed further.  Geotechnologies performed a number of borings to determine the new bottom.  Using the original soldier piles and a number of additional tiebacks and walers, the petroleum riddled soils were removed and expensive pile foundations were avoided.