Aquitards generally have a strong influence on the sustainable yield of aquifers and provide a degree of aquifer protection ( aquitard integrity) from surface contamination. This primarily field-based research seeks to define and characterize aquitard units through a combination of complimentary methods to determine their physical, chemical and microbial properties. Knowledge of these properties helps in determining what combination of geophysical and geobiochemical characteristics offer good aquitard integrity against different types of contamination, for example, DNAPLs, radionuclides, viruses and pathogens, organic and inorganic solutes. G360 aquitard research is focused on both clayey unlithified aquitards and lithified (sedimentary rock) aquitards. Assessment of aquitard integrity has significant relevance to aquifer protection, flow system delineation and surface water protection, hazardous waste disposal, siting of deep geologic repositories (DGRs) for radioactive waste, shale gas and oil shale exploitation.