The Triad approach is a next-generation framework for economically managing project decision uncertainties at hazardous waste site cleanups, including both the characterization and remediation phases. A critical Triad product is a conceptual site model accurate enough to support productive, cost-effective decisions about contaminant presence, receptor exposure, and risk reduction design. The Triad has three primary components, systematic planning, dynamic work strategies, and real-time measurements systems. The Triad approach draws on technical knowledge and expertise gained over the past 20 to 30 years of hazardous waste site cleanup, incorporating advancing science into site management policies and practices. The Triad explicitly recognizes that environmental matrices are heterogeneous in composition and contamination is heterogeneous in distribution. The Triad approach copes with the complexities caused by heterogeneity by: 1) using project-specific conceptual site models to distinguish different contaminant populations with respect to project decisions, 2) incorporating a second-generation model for environmental data quality, and 3) exploiting new characterization, analytical tools, and work strategies to expedite and improve site decision-making.

The full-benefits of the Triad are realized when systematic planning is combined with dynamic work strategies and real-time measurement systems. There may be instances where dynamic work strategies are not possible or appropriate. In these cases, portions of the Triad can still be implemented with significant benefits.