Fifteen foundries from three states participated in this study. Atterberg limits, compaction characteristics, bentonite content, particle size distribution, and resistance to physical and chemical distress were determined for all foundry sands. Based on this study, guidelines for the construction of barrier layers with foundry sand were developed. Only green sands can be readily used in the construction of barrier layers. For other type of foundry sands, such as chemically bonded sand, addition of bentonite is necessary.
Foundry sands are less sensitive to compaction water content than clayey soils.
This makes barrier layers easier to construct with foundry sand than with clayey soils.