Over the years, my students and I have developed new approaches for high-resolution characterization of unconsolidated aquifers, based largely on direct-push technology. The approach provides details about the stratigraphic controls on groundwater flow and solute transport at a scale of measurement that is not possible with conventional drilling-based methods. Ongoing research in alluvial aquifers demonstrates the capabilities of our approaches, and includes examination of recharge at floodplain-terrace and at stream-aquifer interfaces. The new tools are extremely relevant for environmental site characterization projects and the design of remediation strategies at contaminated sites. Recently, we have used direct-push tools to conduct a tracer test at a uranium-contaminated, DOE site and at a large municipal landfill site.