2.0 CONCEPTUAL HYDROLOGIC MODEL
Most predictive efforts require the formulation of a
model which adequately represents the system to be anal-
yzed.   This representation depends heavily upon the ex-
pected predictive use of the model.      Once the model has
been prepared and the user is assured of its accuracy in
representing the system in question, predictions can be
made by imposing a change in the system and observing the
response of the model.
We consider that the model which has been developed
for this effort adequately represents the hydrologic system
at the Crandon site. The approximate extent of the model
is the plan area bounded by Swamp Creek on the north,
Ground Hemlock Slough on the east, Pickerel Lake on the
south and Rolling Stone and Rice Lakes on the west.      The
actual boundary limits of the model are the stream channels
and lake shores which are recharged by the groundwater.
Figure 2.1 shows the study area and assumed boundaries of
the hydrogeologic model.    In cross-section the model con-
sists of a layer of coarse grained stratified drift materi-
al which is effectively continuous over the plan area of
the model.   An idealized section is shown in Figure 2.2.
The saturated thickness of this layer of coarse grained
stratified drift varies over the model area.      An isopach
map of the saturated thickness of the coarse grained stra-
tified drift was constructed from the borehole data, geo-
logic sections and areal trends inferred from the block
diagrams (included in Reference 1) and is included in Fig-
ure 2.3.   The natural water input to the hydrologic model
is the rainfall and snowmelt infiltration which percolates
into this layer of coarse grained stratified drift. This
idealized hydrogeologic system is based on the findings
presented  in the Geotechnical    Investigation(1) and Pump
Test and Analysis(2) prepared previously by Golder Associ-

ates.

Golder Associates

March, 1982

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7R6085