The coastal plain that hosts Garden Grove sits on deep alluvial deposits with silt, sand, and clay layers that vary across short distances. Shallow groundwater sits between 3 and 6 feet below grade in many blocks, which directly affects how impact energy propagates through the soil column. In a dynamic compaction design for Garden Grove we must first define the target depth of improvement, drop weight, and grid spacing based on the fill history and foundation loads. Before the crane arrives we run a resistivity survey to map subsurface anomalies that could absorb energy unevenly. That data lets our team adjust the pattern so each drop delivers consistent densification across the entire pad.
Shallow groundwater in Garden Grove forces us to monitor pore pressure between each compaction pass to avoid hydraulic fracturing of the soil.