2008 ISGS Annual Report - University of Illinois at Urbana-Champaign

Wetlands and Environmental Assessments
Tollway Runoff Monitoring
Project Begins
Wetland scientists at the
Illinois State Geological
Survey began a 3-year
project monitoring water
quality for the Illinois State
Toll Highway Authority.
The project goal is to
determine the effectiveness
of bioswales that are now
under construction along
a section of I-294, which is
being widened.
Bioswales, or vegetated
wetland drainageways, are
intended to lessen the impact
of contaminants from
tollway runoff on groundwater
quality. The bioswales
are intended to increase
runoff contact time with
Charles Knight, ISGS scientist in the Wetlands
Section, collects discharge data from a
roadside ditch at the future site of a bioswale
along I-294 in Des Plaines, Illinois.
wetland vegetation and soils, which transform nutrients and remove
suspended sediment and certain other pollutants.
The first phase of this project involves the emplacement of automated
samplers, flow meters, and water-quality data loggers at three stations
along the tollway. The information provided by these instruments
will help the scientists to monitor runoff prior to construction of the
bioswales and to establish the baseline loads of target contaminants
leaving the roadway onto adjacent lands owned by the Forest
Preserve District of Cook County or directly into the Des Plaines
River. Later phases will measure the effectiveness of the bioswales
after construction and compare the quality of runoff discharged by the
bioswales to the present load.
Preliminary Site Assessments
The Environmental Site Assessments Section of the ISGS conducts
preliminary environmental site assessments for the Illinois Department
of Transportation (IDOT). These assessments are designed to
provide IDOT with environmental information early in project planning
stages, so that State infrastructure projects can be completed on
time and on budget. Site assessments are conducted in all nine IDOT
districts and can range in scope from work at intersections to major
bridge and highway projects. Potential hazards identified by ISGS
work can then be avoided, remediated, or mitigated, depending on
IDOT project needs. During the period covered by this annual report,
the section completed 107 site assessments for IDOT.
Interstate 355 Extension Opens
Illinois State Geological Survey staff members played a large role
in the environmental studies for the I-355 tollway south extension
from I-55 to I-80, which opened on November 11, 2007. Beginning in
1989, various proposed alignments were evaluated for their potential
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Site assessment equipment during the environmental
studies along the I-355 extension route
from I-55 to I-20.
for hazardous waste,
and the results of those
studies were used in
alignment selection.
The studies continued
through 2002, when
specific parcels to be acquired
were assessed for
potential environmental
hazards in a cooperative
agreement between the
Illinois Department of
Transportation and the
Illinois State Toll Highway
Authority.
Significant delays in construction
were caused
by the presence of the
Hines emerald dragonfly,
a federally endangered
insect that inhabits seeps along the tollway route in the lower Des
Plaines River valley. Scientists at the ISGS were involved in several
phases of habitat planning for the tollway. Involvement began in the
early 1990s with a study on the impacts on dragonfly habitat from the
potential reduction of seep discharge caused by the loss of infiltration
from new impermeable roadway surfaces. Routing and design alterations
were suggested at that time. The ISGS is currently working to
help mitigate the tollway’s impacts on the dragonflies by studying the
hydrology and geochemistry of the current dragonfly habitats to help
design new dragonfly habitat restoration areas.
ISGS Provides Environmental
Work for Mississippi River Bridge
On Monday, December 17, 2007, the McKinley Bridge, which connects
Venice, Illinois, to St. Louis, Missouri, reopened to traffic. Built
in 1910 for rail lines, the
bridge was closed in 2001
for major reconstruction.
ISGS Environmental
Site Assessments staff
conducted environmental
studies for the Illinois Department
of Transportation
prior to the rehabilitation
of the bridge, which
included evaluation of
potential excavation sites
for the presence of hazardous
waste. Formerly a
toll bridge, the bridge has
reopened as a toll-free
bridge and now has lanes
devoted to bicycle and
pedestrian traffic.
McKinley Bridge connecting Venice, Illinois, to
St. Louis, Missouri.