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2010 Release of CADDIS (Causal Analysis/Diagnosis Decision Information System)

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Environmental Protection Agency (EPA).


Notice of public release.


The U.S. Environmental Protection Agency (EPA) is announcing the public release of the 2010 version of the Causal Analysis/Diagnosis Decision Information System (CADDIS). This Web site was developed to help scientists find, develop, organize, and use environmental information to improve causal assessments of biological impairment. The CADDIS Web site was developed and prepared by EPA's National Center for Environmental Assessment (NCEA), in the Office of Research and Development (ORD), and is available at​caddis.


The 2010 CADDIS Web site will become publically available on September 24, 2010.

Additional Information: For additional information on the CADDIS Web site, please contact the Information Management Team via mail: Mailcode 8601P, National Center for Environmental Assessment, U.S. Environmental Protection Agency, 1200 Pennsylvania Avenue, NW., Washington, DC 20460; telephone: 703-347-8561; facsimile: 703-347-8691; or e-mail:

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Over a thousand water bodies in the United States are listed by states as biologically impaired. For many of these sites, the cause of impairment is reported as “unknown.” Before appropriate management actions can be formulated for impaired water bodies, the causes of biological impairment (e.g., excess fine sediments, nutrients, toxics, and other stressors) must be identified. Effective causal analyses require knowledge of the mechanisms, symptoms, and stressor-response relationships for various stressors, as well as the ability to use that knowledge to draw appropriate, defensible conclusions. To aid in these causal analyses, NCEA developed CADDIS, a web-based decision support system to help regional, state, and tribal investigators find, access, organize, and share information useful for causal evaluations in aquatic systems. CADDIS is based on EPA's Stressor Identification process, which is a formal method for identifying causes of impairments in aquatic environments. Features of CADDIS include a step-by-step guide to conducting causal assessments; a summary of relevant causal assessment history and concepts; summary information for common sources and stressors; applied examples of causal assessment methods; information on basic and advanced data analyses; downloadable software tools; and an online application for collaborating on conceptual diagrams and using them to update and access a database of supporting literature.

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Dated: September 20, 2010.

Lynn Flowers,

Acting Director, National Center for Environmental Assessment.

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[FR Doc. 2010-23966 Filed 9-23-10; 8:45 am]