| (a) Dredging and the disposal and placement of dredged
material shall avoid and otherwise minimize adverse effects to coastal
waters, submerged lands, critical areas, coastal shore areas, and
Gulf beaches to the greatest extent practicable. The policies of this
section are supplemental to any further restrictions or requirements
relating to the beach access and use rights of the public. In implementing
this section, cumulative and secondary adverse effects of dredging
and the disposal and placement of dredged material and the unique
characteristics of affected sites shall be considered.
(1) Dredging and dredged material disposal and placement
shall not cause or contribute, after consideration of dilution and
dispersion, to violation of any applicable surface water quality standards
established under §26.21 of this title (relating to Policies
for Discharge of Municipal and Industrial Wastewater to Coastal Waters).
(2) Except as otherwise provided in paragraph (4) of
this subsection, adverse effects on critical areas from dredging and
dredged material disposal or placement shall be avoided and otherwise
minimized, and appropriate and practicable compensatory mitigation
shall be required, in accordance with §26.23 of this title (relating
to Policies for Development in Critical Areas).
(3) Except as provided in paragraph (4) of this subsection,
dredging and the disposal and placement of dredged material shall
not be authorized if:
(A) there is a practicable alternative that would have
fewer adverse effects on coastal waters, submerged lands, critical
areas, coastal shore areas, and Gulf beaches, so long as that alternative
does not have other significant adverse effects;
(B) all appropriate and practicable steps have not
been taken to minimize adverse effects on coastal waters, submerged
lands, critical areas, coastal shore areas, and Gulf beaches; or
(C) significant degradation of critical areas under §26.23(a)(7)(E)
of this title would result.
(4) A dredging or dredged material disposal or placement
project that would be prohibited solely by application of paragraph
(3) of this subsection may be allowed if it is determined to be of
overriding importance to the public and national interest in light
of economic impacts on navigation and maintenance of commercially
navigable waterways.
(b) Adverse effects from dredging and dredged material
disposal and placement shall be minimized as required in subsection
(a) of this section. Adverse effects can be minimized by employing
the techniques in this subsection where appropriate and practicable.
(1) Adverse effects from dredging and dredged material
disposal and placement can be minimized by controlling the location
and dimensions of the activity. Some of the ways to accomplish this
include:
(A) locating and confining discharges to minimize smothering
of organisms;
(B) locating and designing projects to avoid adverse
disruption of water inundation patterns, water circulation, erosion
and accretion processes, and other hydrodynamic processes;
(C) using existing or natural channels and basins instead
of dredging new channels or basins, and discharging materials in areas
that have been previously disturbed or used for disposal or placement
of dredged material;
(D) limiting the dimensions of channels, basins, and
disposal and placement sites to the minimum reasonably required to
serve the project purpose, including allowing for reasonable overdredging
of channels and basins, and taking into account the need for capacity
to accommodate future expansion without causing additional adverse
effects;
(E) discharging materials at sites where the substrate
is composed of material similar to that being discharged;
(F) locating and designing discharges to minimize the
extent of any plume and otherwise control dispersion of material;
and
(G) avoiding the impoundment or drainage of critical
areas.
(2) Dredging and disposal and placement of material
to be dredged shall comply with applicable standards for sediment
toxicity. Adverse effects from constituents contained in materials
discharged can be minimized by treatment of or limitations on the
material itself. Some ways to accomplish this include:
(A) disposal or placement of dredged material in a
manner that maintains physiochemical conditions at discharge sites
and limits or reduces the potency and availability of pollutants;
(B) limiting the solid, liquid, and gaseous components
of material discharged;
(C) adding treatment substances to the discharged material;
and
(D) adding chemical flocculants to enhance the deposition
of suspended particulates in confined disposal areas.
(3) Adverse effects from dredging and dredged material
disposal or placement can be minimized through control of the materials
discharged. Some ways of accomplishing this include:
(A) use of containment levees and sediment basins designed,
constructed, and maintained to resist breaches, erosion, slumping,
or leaching;
(B) use of lined containment areas to reduce leaching
where leaching of chemical constituents from the material is expected
to be a problem;
(C) capping in-place contaminated material or, selectively
discharging the most contaminated material first and then capping
it with the remaining material;
(D) properly containing discharged material and maintaining
discharge sites to prevent point and nonpoint pollution; and
(E) timing the discharge to minimize adverse effects
from unusually high water flows, wind, wave, and tidal actions.
(4) Adverse effects from dredging and dredged material
disposal or placement can be minimized by controlling the manner in
which material is dispersed. Some ways of accomplishing this include:
(A) where environmentally desirable, distributing the
material in a thin layer;
(B) orienting material to minimize undesirable obstruction
of the water current or circulation patterns;
(C) using silt screens or other appropriate methods
to confine suspended particulates or turbidity to a small area where
settling or removal can occur;
(D) using currents and circulation patterns to mix,
disperse, dilute, or otherwise control the discharge;
(E) minimizing turbidity by using a diffuser system
or releasing material near the bottom;
(F) selecting sites or managing discharges to confine
and minimize the release of suspended particulates and turbidity and
maintain light penetration for organisms; and
(G) setting limits on the amount of material to be
discharged per unit of time or volume of receiving waters.
(5) Adverse effects from dredging and dredged material
disposal or placement operations can be minimized by adapting technology
to the needs of each site. Some ways of accomplishing this include:
(A) using appropriate equipment, machinery, and operating
techniques for access to sites and transport of material, including
those designed to reduce damage to critical areas;
(B) having personnel on site adequately trained in
avoidance and minimization techniques and requirements; and
(C) designing temporary and permanent access roads
and channel spanning structures using culverts, open channels, and
diversions that will pass both low and high water flows, accommodate
fluctuating water levels, and maintain circulation and faunal movement.
(6) Adverse effects on plant and animal populations
from dredging and dredged material disposal or placement can be minimized
by:
(A) avoiding changes in water current and circulation
patterns that would interfere with the movement of animals;
(B) selecting sites or managing discharges to prevent
or avoid creating habitat conducive to the development of undesirable
predators or species that have a competitive edge ecologically over
indigenous plants or animals;
(C) avoiding sites having unique habitat or other value,
including habitat of endangered species;
(D) using planning and construction practices to institute
habitat development and restoration to produce a new or modified environmental
state of higher ecological value by displacement of some or all of
the existing environmental characteristics;
(E) using techniques that have been demonstrated to
be effective in circumstances similar to those under consideration
whenever possible and, when proposed development and restoration techniques
have not yet advanced to the pilot demonstration stage, initiating
their use on a small scale to allow corrective action if unanticipated
adverse effects occur;
(F) timing dredging and dredged material disposal or
placement activities to avoid spawning or migration seasons and other
biologically critical time periods; and
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