The Groundwater Statistics and Monitoring Compliance (GSMC) web-based guidance is designed to help users without deep statistical expertise to understand the statistical techniques and methods related to groundwater cleanup and how to use them in all project life cycle stages: release detection, site characterization, remediation, monitoring and closure. The GSMC web-based technical and regulatory guidance document brings clarity to the planning, implementation, and communication of groundwater statistical methods and should lead to greater confidence and transparency in the use of groundwater statistics for environmental site management.