Sites 30 to 34 are located on broad expanses of glacial outwash. Major disadvantages
of these
are the shallow depth to groundwater and the highly permeable soils. The
need for soil borrow
to build the dikes and the final cover would increase the overall impact
of a disposal facility ox
sites. These sites have sufficient volume to hold the tailings and would
not block streams or o(
large areas of wetlands. These sites would be at or below the mill elevation
making gravity or
pressure pumping of tailings possible.

Sites 40 to 42 are drumlin uplands at or above the mill elevation thus eliminating
the advantage
gravity flow systems. The soils consist of well-consolidated, moderate to
low permeability sill
sands (glacial till) and provide the greatest separation between the ground
surface and the watt
table. These sites also minimize transport distances, eliminate most wetland
crossings by pipe
and do not interfere with major surface watercourses. The upland locations
have the best soils
constructing dikes and liners, greater potential for deeper excavations,
and decreased need for
borrow areas. Sites 40 to 42 have only minor confining topographic features,
however, and upi
sites with earthen embankments (the proposed design) are more expensive than
valley fills in t4
construction and material costs. This cost however, is offset by pipeline
rights-of-way, constr
and operation costs for distant sites. The drumlin sites closest to the mine/mill
are west and e
Little Sand Lake, sites 40 and 41, respectively. Other upland areas are more
distant, for exam
west of Lake Metonga, between Lakes Metonga and Lucerne, and north of Lake
Lucerne.

Only relatively subtle differences exist between the two best upland sites,
sites 40 and 41. Bol
would be close to the proposed mill and would meet the "least overall
environmental impact"
requirement. Site 41, however, has less permeable soils, provides more separation
from ground
is approximately the same distance from the mill, and has less need for a
soil borrow area. Sit
consistent with administrative code requirements emphasizing the location
of the MWDF withi
same drainage area as the mine/mill. By locating the MWDF where surface water
impacts and
drainage area disturbances are minimal, direct environmental disturbances
would be minimized

Alternative arrangements of the tailings ponds at site 41 were considered
to reduce wetland
disturbance. These arrangements, however, would have greater surface area
and drainage bay
disruption with consequent erosion and siltation impacts compared to a compact
site which wo
cover some wetlands.

MINE REFUSE DISPOSAL FACILITY (MRDF)

Some alternative on-site locations for the landfill could be utilized. Advantages
of the proposj
location are the depth to groundwater and leachate attenuating capacity of
the underlying till)
The proposed location, however, confines the MWDF and reclaim ponds. This
location also mal
interfere with efficient transport of soil materials between the MWDF and
the construction
area. The landfill site might be a convenient borrow source or storage location
for soil stock
Landfill interference with MWDF construction and operation could be eliminated
if one of the
following alternative sites was utilized:

1. The wooded area north of the preproduction ore storage pad would be close
to the mill ait
    source of all refuse except for air curtain destructor wastes from MWDF
clearing and
    operations. The soils in this area are suitable for landfill siting.
This location is close td
    water treatment plant for leachate treatment.

2.  A location west of the reclaim ponds would be suitably isolated (greater
than 1,000 feet.,
    both Duck and Skunk Lakes) and the soils are acceptable. This site is
covered by till soi.
    a depth of approximately 50 feet to groundwater. This location would
be easily accessib
    both the mill and the MWDF by a side road extending from the haul road.
Leachate co
    pumped to the treatment plant by a small-diameter pipe along the haul
road pipeline co

The two alternative sites, however, would cause more land disturbance and
require more mo
wells.



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