UNITED STATES ENVIRONMENTAL PROTECTION AGENCY
REGION 5
77 WEST JACKSON BOULEVARD
CHICAGO. IL 60604-3590
December 21,2009
EPA CONCLUSIONS REGARDING CITIZEN CONCERNS ON THE DMDF
Over the past months, members of the Great Lakes Bay community have approached EPA with a
number of concerns about the U.S. Army Corps of Engineers Saginaw River dredging project
and its dredged materials disposal facility (DMDF). Many of the issues are outside EPA's
jurisdiction, but the agency worked with the Corps of Engineers to respond to community
concerns.
Impact of dredging on drinking water supplies
Some area residents feared that contaminants suspended during dredging would move into
Saginaw Bay and affect the municipal drinking water intakes there. EPA and the Corps have
concluded that this would not occur. To help allay concerns, EPA sampled drinking water being
drawn from Saginaw Bay when there was no dredging activity to establish background
conditions. Samples were collected of both the water entering the municipal water treatment
systems and of the treated water sent to the local communities. EPA analyzed the samples for a
wide range of chemicals including dioxins, furans, volatile organics, semi-volatile organics,
PCBs, pesticides and metals and found no contamination. The results from this background
testing are available on EPA's Web site. EPA is planning another round of sampling in spring
2010 when the Corps is expected to resume dredging.
Impact of the DMDF
Public concerns about the DMDF focused on several potential problems: odors, effects on
wildlife, standing water allowing mosquitoes to breed; and residential well contamination. EPA
asked the Corps of Engineers to address these issues. After a series of meetings, the Corps
developed a fact sheet that EPA believes is responsive to the concerns that were raised. Below
are summaries of Corps answers to some of the questions addressed. The entire fact sheet is
attached and is online at http://bit.ly/usace_dmdf
• Will the DMDF affect nearby residential wells? No The DMDF is constructed
over natural clay soils and is surrounded by clay dikes that prevent contaminants from
leaving the site. The Corps has installed a network of monitoring wells around the
DMDF and will take immediate action if ground water is affected. EPA has also
reviewed available information from wells in the general area of the residential wells
and consulted with the Saginaw County Public Health Department. Based on this,
EPA has determined that nearby residential wells are not used for drinking because
the water quality in the area is brackish, of poor quality.
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• What will be the effect of the DMDF on wildlife? The Corps is taking a number of
steps to minimize the exposure of wildlife to dredged materials. For example, the
Corps plans to dredge the most contaminated material first and dispose of it in the
bottom of the DMDF. Then, it will be buried under less contaminated material.
• Why is the area surrounding the DMDF sometimes flooded? The area
surrounding the DMDF is intentionally flooded periodically to provide a place for
wildlife to live and reproduce. It is owned by Saginaw County and is being managed
as a wetland mitigation project in cooperation with the State of Michigan.
• Will there be odor problems related to the DMDF? Odor is not generally an issue
at DMDFs. However, the Corps will be monitoring for this and will take steps to
correct any problems.
The Corps of Engineers fact sheet provides contact information for additional information
regarding the DMDF. For questions about EPA's Superfund cleanup of the Tittabawassee River,
Saginaw River & Bay, please contact EPA community involvement coordinator Don de Blasio
(312-886-4360 or deblasio.don@epa.gov). There is also extensive information on EPA's Web
site at epa.gov/region5/sites/dowchemical.
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U.S. Army Corps of Engineers fact sheet
Upper Saginaw River DMDF
Fact Sheet
The Corps of Engineers (USAGE) constructed a Dredged Material Disposal Facility
(DMDF) for placement of sediments from maintenance dredging of the Upper Saginaw
River Federal Navigation Channel. The facility is located on 281 acres of farmland
located within portions of Saginaw and Bay Counties, Michigan and is designed to hold
3.1 million cubic yards of material to be dredged over a minimum 20-year period. The
facility site is underlain by clay and has clay perimeter dikes constructed to a height of
approximately 11 feet. The proposed DMDF includes a weir to release effluent to the
Saginaw River after meeting State of Michigan 401 water quality standards. Sediments
to be placed in the DMDF contain low levels of contamination. The local sponsor for this
project is Saginaw County. After the site is full it will be turned over to the county who
will then be responsible for maintenance and monitoring.
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U.S. Army Corps of Engineers fact sheet
FREQUENTLY ASKED QUESTIONS:
Will the DMDF affect nearby residential wells?
The DMDF will not affect nearby residential wells because the DMDF, constructed on a
site with natural clay soils with dikes constructed of clay with a six foot deep compacted
clay "key", provides a barrier to keep contaminants from leaving the site. In order to
verify that contaminants are not leaving the site, the Corps has installed 28 ground water
monitoring wells around the DMDF, including in the residential area between the facility
and the Saginaw River. These monitoring wells will be sampled to see if the DMDF is
affecting ground water quality at the site. The Corps will take immediate action if it is
determined ground water is being affected by the placement facility. Ground water
monitoring will continue for several dredge cycles, and then the frequency will be re-
evaluated in consultation with Michigan Department of Environmental Quality.
What will be the effect of the DMDF on wildlife?
Wildlife exposure will be limited at the site through several controls. Dredging will most
likely take place in the summer and fall so the material in the site will be allowed to settle
during the winter months. Ice conditions will limit exposure during the settling process.
In the spring, the water in the site will be evaluated to determine if it meets water quality
standards and released when it does. Through many years of experience, USAGE has
found that dredged material is very high in nutrient rich soil and seeds, which causes
vegetation to grow quickly. After the first year, plant growth on exposed sediment will
take place and further limit wildlife exposure to the site by covering and stabilizing the
sediment.
USAGE plans to dredge the most contaminated material first and dispose of it in the
lower sections of the DMDF. Then less contaminated material will be dredged and placed
on top of the more contaminated material. This way, the most contaminated sediment will
be buried beneath less contaminated material. When practical, wildlife exposure will also
be limited by using only one cell for sediment placement during dredging operations.
Wildlife exposure to the sediment in the DMDF will not be significantly different from
the exposure it is currently experiencing in the uncontrolled river sediment and the
surrounding habitat.
Why is the area surrounding the DMDF sometimes flooded?
The area surrounding the DMDF is owned by Saginaw County and is being managed by
the county as a wetland mitigation project in cooperation with the State of Michigan. The
area is flooded periodically to provide a place for wildlife to live and reproduce. Saginaw
County is responsive to concerns about long periods of standing water and is willing to
adjust water levels as needed. For additional information concerning this issue please
reach the County at the contact information listed below.
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U.S. Army Corps of Engineers fact sheet
Will there be odor problems related to the DMDF?
Odor has generally not been an issue at USAGE dredged material disposal facilities. The
USAGE will monitor the DMDF for odors and in the event an inspection finds a problem
corrective measures would be taken. If residents detect a smell, it should be reported to
the USAGE'S Chief of operations, at the contact information listed below, who is
responsible for ensuring proper actions are taken to stop the problem. The first cycle of
placement has occurred and no odor has been detected.
Who should I contact if I have concerns, questions or complaints about the DMDF?
USAGE: Wayne Schloop, Chief, Operations and Maintenance Division
313-226-5013
wayne.schloop@usace.army.mil
MDEQ: Brenda Brouillet, MDEQ Saginaw Bay District Office multimedia coordinator
989-686-8025
BROUILLB@michigan.gov
Saginaw County: Jim Koski, Public Works Commissioner
989-790-5258
jkoski@saginawcounty.com
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