Field sampling and laboratory analyses are initiated during the site characterization phase of the Remedial Investigation/Feasibility Study (RI/FS). A preliminary site characterization summary is prepared to provide the lead agency with information on the site early in the process before preparation of the full remedial investigation (RI) report. This summary is useful in determining the feasibility of potential technologies and in assisting both the lead and support agencies with the initial identification of Applicable or Relevant and Appropriate Requirements (ARARs). The summary can also be sent to the Agency for Toxic Substances and Disease Registry (ATSDR) to assist them in performing their health assessments. (see Terms of Environment)
A baseline risk assessment is developed to identify the existing or potential risks that may be posed to human health and the environment by the site. Because this assessment identifies the primary health and environmental threats at the site, it also provides valuable input to the development and evaluation of alternatives during the feasibility study (FS).