The site is underlain by London Clay, however the ground situation has been complicated by previous earthworks and construction, with a made ground area in the southern part of the project. This made ground, of depth up to 4 m, comprises clay matrix with inclusions of some bricks and concrete elements.
In addition, the site will be subject to a significant cut/fill exercise to bring the levels to a suitable development plateau, with up to 3 m of upfill that will generate settlements in the softer top layer of the London Clay. The presence of uncontrolled made ground and upfill requires therefore some ground improvement to ensure a sufficient bearing capacity and reduce the settlements, both total and differential, to acceptable limits. The characteristics of different soil layers, including the recently placed upfill, have been determined precisely thanks to an extensive Cone Penetration Test (CPT) survey on site.