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Resources for Planning Projects that Use Existing Data

Below are some links to help you get started.

Data Quality Assessment - Before existing data can be used, it will need to be assessed against its intended use.
Chapter 3 of the Guidance for Quality Assurance Project Plans (G-5) identifies elements to consider when planning projects that use existing data.
Checklist for Quality Concerns - Draft checklist and list of resources for evaluating secondary data.
Checklist for the Assessment of Existing Information/Secondary Data - Printable form listing elements to track when assessing existing information/secondary data.
EPA's Science Policy Council Assessment Factors - General Assessment Factors for Evaluating the Quality of Scientific and Technical Information.
For additional guidance on performing data quality assessments on existing data, see also these resources.

Resources for Planning Projects that Use Existing Data

Managing the Quality of Environmental Information