Erosion potential of compacted surface soils for multilayered cover system

Industrialization and urbanization have led to a rapid increase in hazardous and reactive wastes that need to be disposed safely. Multilayered cover systems (MLCS) are used for such waste disposal to impede contaminant interaction with the subsurface and atmosphere. Based on multiple forensic studies, soil erosion has been identified as a primary stressor of landfill covers that results in cover failure and exposure to contamination. The pinhole test is one of the most commonly adopted index tests to evaluate the erosion rate of soil. The main objective of this technical note is to measure the erosion potential of a soil at nine different compaction states and three runoffs, which correspond to three forms-rainfall-heavy, excessive, and cloudburst-that can result in significant erosion. A total of 729 pinhole tests on 9 different loamy soils were conducted in the current study, and the individual effects of initial moisture content, soil density, and runoff flow rate are discussed. It is observed that compaction of the surface layer for MLCS can be done at wet optimum moisture content with the highest possible soil density to minimize risk of erosion for all loamy soil. Furthermore, fine fractions of soils (percentage finer than 75 μm) was identified as a parameter that can be used to predict the maximum erosion rate of a soil using a simple linear relation.