Ecological Status and Trends of the Wetland Resource. A nationwide network 

 would be established to monitor the wetland resource. Field surveys would ■ . 

 define the expected range of numerical values within each region for particular 

 chemicals and especially, for biological commimity metrics, across a gradient of 

 sites ranging from nearly-pristine to severely disturbed. 



Waste Assimilative Limits of Wetlands. Observable features which determine 

 the long-term ability of wetlands to retain contaminants and nutrients would be 

 tested. "Safe" loading limits for various substances would be proposed for 

 specific wetland types or regions. Similar kinds of information would also 

 become available from a research effort focused specifically on artificial wetlands 

 and coordinated by EPA-Cinciimati, in cooperation with the Corvallis and Duluth 

 Labs. That study would recommend engineering design factors essential in 

 wetlands constructed by municipalities for tertiary wastewater treatment 



Mitigation: 



Information useful to 401 certification will also originate from ORD'S mitigation 

 research. This research aims to determine if created and restored wetlands replace 

 functions lost by wetland destruction permitted imder Section 404. The research is 

 organized to (1) synthesize current knowledge on wetland creation and restoration, (2) 

 compile 404 permit information on created and restored wetlands, and (3) compare 

 created and naturally occurring wetlands. Research results will be incorporated into a 

 "Mitigation Handbook" useful for designing and evaluating mitigation projects. A 

 literature synthesis being developed as a Provisional Guidance Document wiU be 

 available in 1989. A provisional version of the handbook will be produced in 1990. 

 This win assist States in identifying areas at greatest risk due to 404 permit activities 

 and thus help target 401 certification and water quality standards activities. 



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