FLOOD08883

• County: Statewide
• Basin: Statewide
• Title: Federal Register EPA Guidelines for Specification of Disposal Sites for Dredged or Fill Material
• Date: 12/24/1980
• Prepared By: EPA
• Floodplain - Doc Type: Educational/Technical/Reference Information

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Federal Register / Vol. 45. No. 249 / Wednesday. December 24. 1980 / Rules and Regulations 85349

proposed for discharge snd the msterisl
constituting the substrate at the disposal
site. and any potential changes in
substrate elevation and bottom
contours, including changes outside of
the disposal site which may occur 8S a
result of erosion. slumpage, or other
movement of the discharged material. .
The duration and physical extent of
substrate changes shall also be
considered. The possible loss of
environmental values (I 230.20) and
actions to minimize impact (Subpart H)
shall also be considered in making these
determinations. Potential changes in
substrate elevation and bottom contours
shall be predicted on the basis of the
proposed method. volume: location, and
rate of discharge. 8S well as on the
individual and combined effects of
current patterns, water circulation. wind
and wave action. and other physical
factors that may affect the movement of
the discharged material.
(b) Water circulation. fluctuation. and
salinity determinations. Determine the
nature and degree of effect that the
proposed discharge will have
individually and cumulatively on water.
current patterns. circulation including
downstream flows. and normal water
fluctuation. Consideration shall be given
to water chemistry. salinity. clarity.
color. odor. taste. dissolved gas levels.
temperature. nutrients. and
eutrophication plus other appropriate
characteristics. Consideration shall also
be given to the potential diversion or
obstruction of flow. alterations of
bottom contours. or other significant
changes in the hydrologic regime.
Additional consideration of the possible
loss of environmental values (1230.23-
.25) and actions to minimize impacts
[Subpart H). shall be used in making
these determina Hans. Potential
significant effects on the current
patterns, water circulation. normal
water fluctuation and salinity shall be
evaluated on the basis of the proposed
method. volume. location, and rate of
discharge.
(e) Suspended particulate/turbidity
determJnotions. Determine the nature
and degree of effect that the proposed
discharge will have, individually and
cumulatively. in terms of potential
changes in the kinds and concentrations
of suspended particulate/turbidity in the
vicinity of the disposal site.
Considf'ralion shall be given to the grain
sIze of the material proposed for
discharge. the shape and size of the
plume of ';llspended particulates. the
duration of the discharge and resulting
plume and whether or not the. potential
changes will cause violations of
applicable water quality standards.

Consideration should slso be given to
the possible loss of environmental
values (t Z30.21)<md to sclions for
minimizing impscts (Subpsrt H).
Consideralion shall include the
proposed method. volume. location. snd
ra te of discharge. as well as the
individusl snd combined effects of
current patterns. water circulation and
fluctuations. wind and wave action, and
other physical factors on the movement
of suspended particulates.
(d) Contaminant determinations.
Determine the degree to which the
material proposed for discharge will
introduce. relocate. or increase
contaminants. This determination shall
consider the material to be discharged.
the aquatic environment at the proposed
disposal site, and the availability of
contaminants.
(e) Aquatic ecosystem and organism
determinations. Determine the nature
and degree of effect that the proposed
discharge will have. both individually
and cumulatively. on the structure and
function of the aquatic ecosystem and
organisms. Consideration shall be given
to the effect at the proposed disposal
site of potential changes in substrate
characteristics and elevation. water or
substrate chemistry. nutrients. currents,
circulation. fluctuation. and salinity. on
the recolonization and existence of
indigenous aquatic organisms or
communities. Possible loss of
environmental values U 230.31), and
actions to minimize impacts (Subpart H)
- shall be examined. Tests as described in
i 230.61 (Evaiualion and Testing). may
be required to provide informa tion on
the effect of the discharge material on
communities or populations of
organisms expected to be exposed to it.
(f) Proposed disposal site
determinations. (1) Each disposal site
shall be specified through the
application of these Guidelines. The
mixing zone shall be confined to the
smallest practicable zone within each
specified disposal site that is consistent
with the type of dispersion determined
to be appropriate by the application of
these Guidelines. In a few special cases
under unique environmental conditions,
where there is adequate justification to
show that widespread dispersion by
natural means will result in no
significantly adverse environmental
effects, the discharged material may be
intended to be spread naturally in a very
thin layer over a large area of the
substrate rather than be contained
within the disposal site.
(:2) The permitting authority and the
Regional Administrator shall consider
the following factors in determining the
acceptability of a proposed mixing zone:
(i) Depth of water at the disposal site;

(ii) Current velocity. direction. snd
vsriability st the disposal site;
(iii) Degree of turbulence;
(iv) Strslification attributsble to
causes 8uch as obstructions. salinity or
density profiles at the dispossl site;
(v) Disi:hsrge vessel speed snd
direction. if sppropriate;
(vi) Rste of dischsrge;
(vii) Ambient concentration of
constituents of interest;
(viii) Dredged material chsracterislics.
particularly concentrations of
constituents. amount of material. type of
mSlerial (sand. silt. clay. elc.) snd
settling veloci ties;
(ix) Number of dischsrge actions per
unit of time;
(x) Other factors of the disposal site
that sffect the rates and patterns of
mixing.
(g) Determination of cumulative
effects on the aquatic ecosystem. (1)
Cumulative impacts are the changes in
an aquatic ecosystem that are
sttribulsble to the coileclive effect of a
number of individual discharges of
dredged or fiil material. Although the
impact of a particular discharge may
constitute a minor change in itself. the
cumulative effect of numerous such
piecemeal changes can result in a major
impairment of the water resources and
interfere with the productivity and
water quality of existing aquatic
ecosystems.
[2J Cumulalive effects attributable to
the discharge of dredged or fill material
in waters of the United States should be
predicted to the extent reasonable and
practical. The permitting authority shall
collect information and solicit
information from other sources about
the cumulative impacts on the aquatic
ecosystem. This information shall be
documented and considered during the
decision-making process concerning the
evaluation of individual permit
applications. the issuance of a General
permit. and monito~ing and enforcement
of existing permits.
(h) Determination of secondary
effects on the aquatic ecosystem. (1)
Secondary effects are effects on an
aquatic ecosystem that are associated
with a discharge of dredged or fill
materials, but do not result from the
actual placement of the dredged or fill
material. Information about secondary
effects on aquatic ecosystems shall be
considered prior to the time final section
404 action is taken by permitting
authorities.
(2) Some examples of secondary
effects on an aquatic ecosystem are
fluctuating water levels in an
impoundment and downstream
associated with the operation of a dam.
septic tank leaching and surface runoff