Ground Hemlock Lake is a stratified, moderately hard water (mean hardness
of 112 ppm), alkaline
(average pH of 7.9), clear lake. Low dissolved oxygens levels, typically
lower than one ppm, occur
from June through September in the hypolimnion and blue-green algal blooms
frequently occur in
June, July, and August. Metal concentrations in lake water are below or slightly
above detection
limits.

Rice Lake - Rice Lake is a drainage lake about two miles northwest of the
orebody. The lake has a
surface area of 208 acres and a maximum depth of six feet. The lake bottom
is predominantly muck.
Much of the lake has depths of four feet or less and supports extensive beds
of wild rice as well as
floating and submergent aquatic vegetation. Rice Lake has five inlets (the
largest being Swamp
Creek) and one outlet (Swamp Creek) which flows to the Wolf River. The outlet
has a water control
structure that partially maintains water levels. The watershed is 43 square
miles and the shoreline
consists entirely of wetlands. Black bullhead and pumpkinseed are the dominant
fish species with
northern pike also present.

Rice Lake is an unstratified, moderately hard water (mean hardness of 105
ppm), neutral (average pH
of 7.2), light-brown stained lake. Low dissolved oxygen concentrations occur
in Rice Lake during the
winter and the summer. Metal concentrations in lake water are below or slightly
above detection
limits.

Rolling Stone Lake - Rolling Stone Lake is a drainage lake about 3.5 miles
south of the orebody. The
lake has a surface area of 672 acres and a maximum depth of 12 feet. The
lake bottom is primarily
sand and gravel or muck. About 60% of the shoreline is forested while the
remaining 40% is
wetlands. Three streams on the north shore drain from the hydrologic study
area (Upper Pickerel
Creek, Creek 11-4, and Creek 12-9). Three smaller streams, Creeks 13-2 and
13-5 and Agnes Creek
also enter the lake. The Pickerel Creek outlet has a rocky substrate which
partially maintains lake
water levels. Rolling Stone Lake has a diverse warmwater fishery with walleye
and northern pike the
dominant predators. The abundant panfish community consists largely of yellow
perch.

Rolling Stone Lake is an unstratified, moderately hard water (mean hardness
of 93 ppm), slightly
alkaline (average pH of 7.7), light-brown stained lake. During the winter
of 1978, low dissolved
oxygen levels caused a partial fish kill. Low winter dissolved oxygen levels
chronically stress the
lake's fishery. High levels of phosphorous and chlorophyll-a occur and aquatic
vegetation is
abundant. Metal concentrations in lake water are below or slightly above
detection limits.

A lake district was established in 1975 to provide lake protection and rehabilitation.
The lake
district, with assistance from the DNR, has been active in managing the lake
's resources.

Duck Lake - Duck Lake is a seepage lake about one mile southeast of the orebody
with an effective
watershed of 306 acres. The lake has a surface area of 26 acres, a maximum
depth of 10 feet, and a
predominantly muck bottom. The shoreline is about 60% wetlands (53 acres
of wetland, swamp
conifer or bog vegetation). The remaining 40% of the shoreline vegetation
consists of upland
hardwood and pine. The lake receives surface runoff but does not have any
well-defined permanent
inlets. An intermittent outlet stream flows to Little Sand Lake during high
water levels. This bog
lake has a warmwater fish community of yellow perch, black bullhead, and
mudminnow. These three
species are tolerant of the low dissolved oxygen concentrations which occur
during the winter.

Duck Lake is an unstratified, acidic (average pH of 5.0 during prepump conditions
- see following
paragraph), soft water (mean hardness of 16 ppm), medium-brown colored lake.
The lake, typical of
acid bog lakes, is high in humic content and low in nutrients. Metal concentrations
in Duck Lake
water samples are below or slightly above detection limits.

In June and July 1980, Exxon conducted groundwater pumping tests adjacent
to Duck Lake. The
groundwater discharged to the lake during the pumping test altered the lake
water chemistry. Data
(pH, alkalinity, conductivity, hardness, and total dissolved solids) collected
in 1984 indicates all
parameters except for pH have values within the normal seasonal range found
during pre-pump
conditions. The average pH in Duck Lake was 5.6 during 1984.



- 65 -



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Creek) and one outlet (Swamp Creek) which flows to the Wolf River. The outlet
has a water control
structure that partially maintains water levels. The watershed is 43 square
miles and the shoreline
consists entirely of wetlands. Black bulthead and pumpkinseed are the-, dominant
fish species with
northern pike also present.

Rice Lake is an unstratified, moderately hard water (mean hardness of 105
ppm), neutral (average pH
of 7.2), light-brown stained lake. Low dissolved oxygen concentrations occur
in Rice Lake during the
winter and the summer. Metal concentrations in lake water are below or slightly
above detection
limits.

RollingStone Lake - Rolling Stone Lake is a drainage lake about 3.5 miles
south of the orebody. The
lake has a surface area of 672 acres and a maximum depth of 12 feet. The
lake bottom is primarily
sand and gravel or muck. About 60% of the shoreline is forested while the
remaining 40% is
wetlands. Three streams on the north shore drain from the hydrologic study
area (Upper Pickerel
Creek, Creek 11-4, and Creek 12-9). Three smaller streams, Creeks 13-2 and
13-5 and Agnes Creek
also enter the lake. The Pickerel Creek outlet has a rocky substrate which
partially maintains lake
water levels. Rolling Stone Lake has a diverse warmwater fishery with walleye
and northern pike the
dominant predators. The abundant panfish community consists largely of yellow
perch.

Rolling Stone Lake is an unstratified, moderately hard water (mean hardness
of 93 ppm), slightly
alkaline (average pH of 7.7), light-brown stained lake. During the winter
of 1978, low dissolved
oxygen levels caused a partial fish kill. Low winter dissolved oxygen levels
chronically stress the
lake's fishery. High levels of phosphorous and chlorophyll-a occur and aquatic
vegetation is
abundant. Metal concentrations in lake water are below or slightly above
detection limits.

A lake district was established in 1975 to provide lake protection and rehabilitation.
The lake
district, with assistance from the DNR, has been active in managing the lake's
resources.

Duck Lake - Duck Lake is a seepage lake about one mile southeast of the orebody
with an effective
watershed of 306 acres. The lake has a surface area of 26 acres, a maximum
depth of 10 feet, and a
predominantly muck bottom. The shoreline is about 60% wetlands (53 acres
of wetlands swamp
conifer or bog vegetation). The remaining 40% of the shoreline vegetation
consists of upland
hardwood and pine. The lake receives surface runoff but does not have any
well-defined permanent
inlets. An intermittent outlet stream flows to Little Sand Lake during high
water levels. This bog
lake has a warmwater fish community of yellow perch, black bullhead, and
mudminnow. These three
species are tolerant of the low dissolved oxygen concentrations which occur
during the winter.

Duck Lake is an unstratified, acidic (average pH of 5.0 during prepump conditions
- see following
paragraph), soft water (mean hardness of 16 ppm), medium-brown colored lake.
The lake, typical of
acid bog lakes, is high in humic content and low in nutrients. Metal concentrations
in Duck Lake
water samples are below or slightly above detection limits.

In June and July 1980, Exxon conducted groundwater pumping tests adjacent
to Duck Lake. The
groundwater discharged to the lake during the pumping test altered the lake
water chemistry. Data
(pH, alkalinity, conductivity, hardness, and total dissolved solids) collected
in 1984 indicates all
Parameters except for pH have values within the normal seasonal range found
during pre-pump
conditions. The average pH in Duck Lake was 5.6 during 1984.