[Code of Federal Regulations]
[Title 40, Volume 24]
[Revised as of July 1, 2005]
From the U.S. Government Printing Office via GPO Access
[CITE: 40CFR230.20]

[Page 264]
 
                   TITLE 40--PROTECTION OF ENVIRONMENT
 
         CHAPTER I--ENVIRONMENTAL PROTECTION AGENCY (CONTINUED)
 
PART 230_SECTION 404(b)(1) GUIDELINES FOR SPECIFICATION OF DISPOSAL 
SITES FOR DREDGED OR FILL MATERIAL--Table of Contents
 
Subpart C_Potential Impacts on Physical and Chemical Characteristics of 
                          the Aquatic Ecosystem
 
Sec. 230.20  Substrate.

    Note: The effects described in this subpart should be considered in 
making the factual determinations and the findings of compliance or non-
compliance in subpart B.


    (a) The substrate of the aquatic ecosystem underlies open waters of 
the United States and constitutes the surface of wetlands. It consists 
of organic and inorganic solid materials and includes water and other 
liquids or gases that fill the spaces between solid particles.
    (b) Possible loss of environmental characteristics and values: The 
discharge of dredged or fill material can result in varying degrees of 
change in the complex physical, chemical, and biological characteristics 
of the substrate. Discharges which alter substrate elevation or contours 
can result in changes in water circulation, depth, current pattern, 
water fluctuation and water temperature. Discharges may adversely affect 
bottom-dwelling organisms at the site by smothering immobile forms or 
forcing mobile forms to migrate. Benthic forms present prior to a 
discharge are unlikely to recolonize on the discharged material if it is 
very dissimilar from that of the discharge site. Erosion, slumping, or 
lateral displacement of surrounding bottom of such deposits can 
adversely affect areas of the substrate outside the perimeters of the 
disposal site by changing or destroying habitat. The bulk and 
composition of the discharged material and the location, method, and 
timing of discharges may all influence the degree of impact on the 
substrate.