Superfund Remedial Investigation/Feasibility Study (Site Characterization)

After a site is listed on the National Priorities List (NPL), a remedial investigation/feasibility study (RI/FS) is performed at the site.

The remedial investigation (RI) serves as the mechanism for collecting data to characterize site conditions, determine the nature of the waste, assess risk to human health and the environment, and conduct treatability testing to evaluate the potential performance and cost of the treatment technologies that are being considered. The feasibility study (FS) is the mechanism for the development, screening, and detailed evaluation of alternative remedial actions.

The RI and FS are conducted concurrently - data collected in the RI influence the development of remedial alternatives in the FS, which in turn affect the data needs and scope of treatability studies and additional field investigations. This phased approach encourages the continual scoping of the site characterization effort, which minimizes the collection of unnecessary data and maximizes data quality.

RI/FS Guidance Documents