Physical Properties - A number of tests were run to determine the physical
characteristics of the
tailings. Grain size analyses indicate the largest tailings particles would
be the size of fine sand with
the majority of the particles in the silt-size range. In engineering terms,
the tailings would be
classified as a uniformly graded silt. The tailings had a density greater
than naturally occurring
mineral soils due to the presence of sulfide minerals, such as pyrite, sphalerite,
and chalcopyrite.
Particle size analysis, particle density studies, and other laboratory tests
indicate average
permeabilities (0.014 feet/day) would be relatively high for a silt-sized
material. The higher than
expected permeability was caused by increased pore size and greater number
of pores resulting from
the angular shape of the tailings. Consolidation tests resulted in only a
small reduction of tailings
permeability.

The ore to be removed from the mine, particularly the stringer ore, is generally
unweathered and clay
minerals are scarce. Due to the lack of clay and anticipated particle density
and shape, the tailings
should rapidly settle and consolidate in the tailings ponds. Lab tests indicate
additional consolidation
during tailings accumulation, dewatering, and placement of the grading layer
and final cover should
be minimal.

Chemical and Mineralogical Properties - The chemical and mineralogical testing
of the pilot plant
tailings included elemental analysis, mineralogical examinations, EP toxicity
tests (extraction
procedure), potential acid generation tests, and agitation and column leaching
tests. Results reported
in this section were taken from analyses of tailings typical of those to
be produced by the mill.

    Elemental Analysis - The tailings samples were composed primarily of
iron sulfide (FeS2), silica
    (SiO2), and silicates of aluminum, magnesium and potassium. Pyrite was
the most abundant
    sulfide mineral in the samples and generally comprised over 45% by volume
of the-tailings fines.
    Sulfur content ranged from-22% to 41%. Minor amounts of copper, lead,
zinc, arsenic-iron
    sulfides, and calcium/magnesium carbonate also were present. The following
substances also
    were found: chloride (less than 120 ppm), chromium (18 to 27 ppm), cyanide
(4 to 5 ppm),
    fluoride (450 to 730 ppm), gold (0.5 to 0.9 ppm), manganese (440 to 490
ppm), mercury (2.2 to 3.4
    ppm), nickel (11 to 46 ppm), phosphorus (90 to 120 ppm), selenium (less
than 40 to 110 ppm),
    silver (43 to 58 ppm), and titanium (360 to 660 ppm).

    Potential Acid Generation - All tailings subjected to the acid generation
tests (chemical and
    microbiological confirmation tests) were acid producers.

    Leachate Properties - A series of tests were conducted to determine tailings
leachate
    characteristics under varying conditions. The EP toxicity tests indicate
more metals were
    leached from tailings compared with the waste rock but metal concentrations
were still below
    the threshold levels established for hazardous wastes. Additional leaching
tests also were
    conducted under acid and alkaline conditions. These tests indicate thy
tailings had a buffering
    effect on both acid and alkaline leaching solutions. The elemental composition
of the leachate
    was generally similar but the columns alternately submerged and exposed
to the air leached the
    most due to increased decomposition of sulfide minerals.

    The amount and quality of the leachate was dependent on the amount of
water and oxygen
    coming in contact with the tailings and the presence of the Thiobacillus
ferrooxidans bacterium
    which is pervasive in the environment. Sulfide mineral decomposition
is greatly accelerated by
    biological activity if the pore water becomes very acidic (pH less than
2.5). During the operation
    of each tailings pond the natural acid buffering capacity of the tailings,
lime additions from the
    milling process, and lime added specifically for pH control would limit
the potential for highly
    acidic conditions developing. The initial leachate quality is expected
to include sulfate, calcium,
    magnesium, and manganese as the major constituents. The concentration
of all the constituents
    is expected to decrease with time but sulfate, calcium, and magnesium
should remain the major
    constituents.

Radiological Properties - A comparison of the radioactivity of tailings versus
soil samples collected
near the tailings ponds, the mine/mill, and one of the alternative tailings
ponds locations was
conducted. The tests indicate tailings radioactivity was lower than the radioactivity
of the naturally



tUhe literatur fVlo glapcil soiUls UULn norU LUt Michig I anldl   Wis oUnS
Win.
the literature for glacial- soils in northern Michigan and Wisconsin.



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