Final

Quality System, an Agency-wide program of quality assurance for environmental data. One component of this Quality System is the requirement that investigators use a systematic planning process as mandated in EPA Order 5360.1 CHG 1: Policy and Program Requirements for the Mandatory Agency-wide Quality System (EPA, 1998b). EPA strongly recommends the Data Quality Objectives (DQO) Process as the appropriate systematic planning process for decision making. The DQO Process is an important tool for project managers and planners to define the type, quality, and quantity of data needed to make defensible decisions. Data Quality Objectives Process for Hazardous Waste Site Investigations (QA/G-4HW) i based on the principles and steps developed in Guidance for the Data Quality Objectives Process (QA/G-4) (EPA, 1994b) but is specific to hazardous waste site investigations. This guidance i