Table 3. Slurry impoundment - wetland development: Generalized characterization
of preevaluation site
conditions and reclamation considerations.


Water             Revegetation
Table                Factors
(AMWT)'      (Phytotoxicity/Nutrients)


Direct Revegetation
Potential


RECLAMATION CONSIDERATIONS
Site Preparation


3.0-15.0'     Texture: Coarse grained
Soil Moisture: Droughty
Acidity: Excessive total
potential acidity (60-100
tons CaCO3/acre deficiency
at discharge zone;
decreasing acidity down-
slope.
Nutrients: pH limited.


Intermediate   1.5-3.0'


Texture: Medium-fine
Soil Moisture: Dry surface
(0-6") to saturated sub-
surface (@1.5').
Acidity: Total potential
acidity may be high (50-
60 ton CaCO3/acre
deficiency) at upper por-
tion, decreasing downslope.
Nutrient: pH limited in
surface horizon; low in
saturated root zone
(below 1.5').


Low-Shallow      0.5-1.5'     Texture: Fine texture
Saturated                     silts and clays
Substrate                     Soil Moisture: Moist
surface (0-6") over a
shallow saturated sub-
strate (H<1.5')
Acidity: Total potential
acidity decreasing to mod-
erate levels (10-40 tons
CaCO3/acre), with no
active acidity in saturated
subsurface.
Nutrient: pH limited in
upper horizon; low to
moderate P and K in
saturated zone.
Low-             0.0-0.5'     Texture: Very fine textured
Seasonally                    silts and slimes.
Inundated                     Soil Moisture: Annual
saturation.
Acidity: Limited acid
producing potential
(10-30 tons CaCO3/acre).
with little or no active
acidity due to saturation
and seasonal inundation.
Nutrient: Low to moderate
P and K availability.
Permanently      0.0--15'     Permanent Water - 0.1 -
Impounded                     15.0'.
Acidity: Buffering
capacity should maintain
circumneutral conditions.


Poor Feasibility:
Excessive liming
required-appl ication
rates and potential
acidity are limiting.
Covering may be only
feasible solution for
areas with excessive
acidity.
Moderate Feasibility:
liming or leaching
(with irrigation) may
be required to obtain
initial vegetation
establishment through
leaching of accumu-
lated surface salts.
Good Feasibility:
Shallow saturated
substrate provides
adequate moisture
and prevention of
pyrite acidification
to facilitate direct
planting of adapted
hydrophyte rootstock.
Excellent Feasibility:
Extensive saturated
zone and seasonal
inundation provides
natural leaching and
ideal site conditions
for hydrophyte
establishment (from
both seed and root-
stock).


Remove and/or cover
(>1') toxic materials
in immediate vicinity
of discharge cone
(.c5 acres)-
stability analysis
required.
Direct lime and seed
less toxic downslope
portion.
Surface liming on
limited area with
initial spray
irrigation to esta-
blish annual cover
crop and perennials,
and tree seedlings
on impoundment
perimeter.
Pothole development
through zone to pro-
vide open water
diversity and initial
colonization sites for
hydrophyti c vegetation.
Initial nurse crop
(millet) establish-
ment on scarified
surface followed by
temporary water level
increase (0.5'-0.8')
to enhance seedling
survival.
Pothole development
to enhance diversity
(not required for
vegetation
establishment).


Handplanting required
for all areas due to
surface instability.


Soil cover and limestone:
20-60 tons/acre limestone
and 1,600 cu yds cover/
acre-foot.
Neutralize only: Direct
lime and seed (30-60 tons
CaCO3/acre).
Lime amendment (20-60
ton CaCO3/acre) may be
required on small portion
of upper zone; however,
leaching and rapid cover/
mulch establishment may
negate or reduce
neutralization requirement.
Lime amendment (10 tons
CaCO3/acre) may be bene-
ficial; but not required
for upper zone. Temporary
inundation of millet and
adapted hydrophyte would
preclude need for liming.


No lime amendment neces-
sary if saline adapted
vegetation or hydrophytes
are the principle species.


Buffering capacity and
runoff volume - reservoir
capacity rates should not
require treatments.


Drought tolerant pasture/prairie
grasses and woody shrubs; shal-
low rooting depth will limit
species selection.
Nurse crop establishment
(initial irrigation may be
required) for organic matter
enhancement with inter-
planting of perennials.
Annual nurse/mulch crop and
perennial grass and shrubs on
mesic sites. Hydrophytes
around pothole perimeters.
Moist soil annuals and
perennials at lower
elevations of zone.
A diversity of moist-soil
annuals and perennial hydro-
phytes can be directly
established on the slurry
surface; lowland trees and
woody shrubs can be used to
enhance diversity through
the zone.


Moist soil annuals and peren-
nials adapted to seasonal
inundation. Volunteer
establishment may contribute
significantly after initial
stabilization.
Shoreline emergents,
floating aquatics, and
rooted submergents can be
established to provide
diversity as well as
functional attributes
of sediment and waste
filtration.


'Elevation above mean water table.


Reclamation
Management
Zone


High/
Discharge
Cone


Amendments


Vegetation