The excavation or h2o alternative system is beneficial for soils which might be way too loose to collect an intact Main or clod, or for soils made up of gravel. Both the intact clod and excavation methods are explained in detail by Cresswell and Hamilton (2002). GeoTech Engineering Minimal (GEL) https://humanity56655.blogs100.com/33799599/the-definitive-guide-to-soil-investigation-experts-bangladesh