Document ID: EPA_FRDOC_0001-17064
Agency: epa
Document Type: Notice
Title: Sole Source Aquifer Designation of the Mahomet Aquifer System in East-Central Illinois
Posted Date: 2015-03-19T04:00Z

[Federal Register Volume 80, Number 53 (Thursday, March 19, 2015)]
[Notices]
[Pages 14370-14371]
From the Federal Register Online via the Government Printing Office [www.gpo.gov]
[FR Doc No: 2015-06365]

=======================================================================
-----------------------------------------------------------------------

ENVIRONMENTAL PROTECTION AGENCY

[FRL-9923-75-Region 5]

Sole Source Aquifer Designation of the Mahomet Aquifer System in 
East-Central Illinois

AGENCY: Environmental Protection Agency (EPA).

ACTION: Notice of final determination.

-----------------------------------------------------------------------

SUMMARY: Notice is hereby given that pursuant to the Safe Drinking 
Water Act (SDWA) Section 1424(e) and in response to a petition by a 
coalition of cities, a town, villages, and a public university in east-
central Illinois, the Regional Administrator for Region 5 of the 
Environmental Protection Agency (EPA) has determined that a portion of 
the Mahomet Aquifer System in east-central Illinois is a sole or 
principal source of drinking water and if contaminated, would create a 
significant hazard to public health. As a result of this action, all 
projects receiving Federal financial assistance are subject to review 
by EPA regarding whether such projects may contaminate the designated 
aquifer system through a recharge zone so as to create a significant 
hazard to public health.

DATES: This determination is effective immediately.

FOR FURTHER INFORMATION CONTACT: William Spaulding, EPA Region 5, Water 
Division, Ground Water and Drinking Water Branch, by mail at 77 W. 
Jackson Boulevard, Chicago, IL 60604; by telephone at (312) 886-9262; 
or by email at spaulding.william@epa.gov.

SUPPLEMENTARY INFORMATION: 

I. Background

    Section 1424(e) of the SDWA provides as follows:

    If the Administrator determines, on his own initiative or upon 
petition, that an area has an aquifer which is the sole or principal 
drinking water source for the area and which, if contaminated, would 
create a significant hazard to public health, he shall publish 
notice of that determination in the Federal Register. After the 
publication of any such notice, no commitment for Federal financial 
assistance (through a grant, contract, loan guarantee, or otherwise) 
may be entered into for any project which the Administrator 
determines may contaminate such aquifer through a recharge zone so 
as to create a significant hazard to public health, but a commitment 
for Federal financial assistance may, if authorized under another 
provision of law, be entered into to plan or design the project to 
assure that it will not so contaminate the aquifer.

42 U.S.C. 300h-3(e). The authority to designate an aquifer under this 
section has been delegated to the Regional Administrator.
    EPA in general considers a ``sole or principal source'' or sole 
source aquifer (SSA) to be an aquifer or aquifer system that is needed 
to supply fifty percent or more of the drinking water ``for the aquifer 
service area,'' and for which there is no reasonably available 
alternative source or sources that could physically, legally, and 
economically supply those dependent upon the aquifer. See U.S. EPA, 
1987, Sole Source Aquifer Designation Decision Process, Petition Review 
Guidance (``EPA Petition Review Guidance''). A portion of an aquifer 
can be designated if it is hydrogeologically separate from the rest of 
the aquifer. Id. at 6. Similarly, a system of hydrogeologically 
connected aquifers can be designated as an SSA. Id.
    On December 12, 2012, EPA received a petition to designate a 
portion of the Mahomet Aquifer System in east-central Illinois as an 
SSA from the City of Champaign and several partners, including the 
Cities of Urbana, Delavan, and Gilman; the Town of Normal; the Villages 
of Savoy, Mansfield, and Mahomet; and the University of Illinois at 
Urbana-Champaign. Following receipt of the petition, additional 
entities expressed support for the petition, including Champaign and 
DeWitt Counties; the Cities of Clinton and Watseka; the Villages of 
Armington and Waynesville; and the Illinois-American Water Company.
    In response to the petition, EPA published a notice of its intent 
to designate a portion of the Mahomet Aquifer System in east-central 
Illinois as an SSA and announced two Public Hearings in Champaign, 
Illinois on May 13, 2014, and in Morton, Illinois on May 14, 2014. This 
notice was published in two newspapers of general circulation in the 
area: The Champaign News Gazette and Peoria Journal Star, on March 12, 
2014. This notice also announced the request for written comments 
during the public comment period from March 13, 2014 to June 12, 2014.
    The public comments received by EPA generally support designation. 
EPA also received significant comments and additional scientific 
studies on the geology of the Mahomet Aquifer System during the comment 
period. These comments and additional studies required extensive 
evaluation and consideration. EPA has responded to the public comments 
in a document titled: ``Responsiveness Summary--Sole Source Aquifer 
Petition for the Mahomet Aquifer System in East-Central Illinois--March 
2015.'' The Responsiveness Summary and other relevant documents are 
available for public inspection during normal business hours at the 
following locations: Champaign Public Library, 200 W. Green St., 
Champaign, Illinois; Bloomington Public Library, 205 E. Olive St., 
Bloomington, Illinois; Pekin Public Library, 301 S. Fourth St., Pekin, 
Illinois; Havana Public Library, 201 W. Adams St., Havana, Illinois; 
Watseka Public Library, 201 S. 4th St., Watseka, Illinois; U.S. EPA's 
Region 5 Office Library, 77 W. Jackson Blvd., Chicago, Illinois.

II. Description of Mahomet Aquifer System in East-Central Illinois

    The Mahomet Aquifer is located in Illinois, Indiana, Ohio, and 
possibly West Virginia. This SSA designation is for a hydraulically and 
hydrogeologically distinct portion of the aquifer system in east-
central Illinois bounded in the east by the Iroquois River and the 
North Fork of the Vermilion River and in the west by the Illinois 
River. Within the SSA area, deposits of saturated sand or sand and 
gravel found within the Quaternary

[[Page 14371]]

deposits are aquifers that provide most (approximately 94 percent) of 
the water used in this region. These Quaternary deposits directly 
overlie the bedrock and bury features on the bedrock surface. As a 
result of geological processes that have shaped the region, the 
hydrogeology is very complex.
    To define the boundary of the designated Mahomet Aquifer System, 
EPA verified that the 500-foot contour line and saturated thicknesses 
of the Mahomet Aquifer best represent the buried valleys that contain 
enough sand and gravel to be significant sources of groundwater. The 
Mahomet Aquifer has been mapped by studies that used boreholes to 
penetrate into the top surface of the Mahomet sand, providing greater 
accuracy on the extent of the aquifer than the bedrock surface alone. 
Recharge of the Mahomet Aquifer occurs throughout the designated SSA 
area. While much of the eastern portion of the SSA area is confined by 
low-permeability glacial till, studies demonstrate that recharge of the 
principal aquifer is occurring in this area, even though it may be 
occurring at a low rate. Recharge of the Mahomet Aquifer occurs at a 
much greater rate in the western portion of the SSA area. In addition, 
there are studies documenting connections between the aquifer zones in 
the shallower formations, namely the Glasford Formation, and the 
Mahomet Aquifer within the SSA area. For these reasons and those 
explained in more detail in the Responsiveness Summary, EPA is 
designating the entire aquifer system within the SSA area.

III. Basis for Determination

    In accordance with Section 1424(e) of the SDWA, 42 U.S.C. 300h-
3(e), the Regional Administrator considered the following factors to 
determine whether the petition should be granted: (1) Whether the 
Mahomet Aquifer System in east-central Illinois is the area's sole or 
principal source of drinking water; and (2) whether contamination of 
the aquifer system would create a significant hazard to public health. 
Based on information available to EPA, the Regional Administrator makes 
the following findings \1\ in favor of designating the Mahomet Aquifer 
System in east-central Illinois as an SSA:
---------------------------------------------------------------------------

    \1\ The findings that support designation are set out more fully 
in an EPA publication titled: ``Support Document for Proposed 
Designation of the Mahomet Aquifer System as a Sole Source.'' This 
document is available to the public at the locations identified 
above.
---------------------------------------------------------------------------

    (1) The Mahomet Aquifer System provides approximately 94 percent of 
the drinking water to the service area today. This exceeds the 50 
percent usage criteria for SSA designation in EPA's guidance. EPA 
Petition Review Guidance at 8. Moreover, demand on this aquifer system 
is expected to increase in the future. The Mahomet Aquifer System 
currently provides an estimated 53 million gallons per day (mgd) of 
drinking water to approximately 120 public water supplies and thousands 
of rural wells, together serving over 500,000 people. There currently 
are no intakes from surface waters for public water supplies within the 
aquifer service area.
    (2) Over 50 percent of the population in the Mahomet Aquifer System 
service area would be unable to find either a physically available or 
economically feasible alternative source of drinking water should the 
aquifer system become contaminated. Potential alternative sources of 
drinking water near the proposed aquifer service area include: (1) Sand 
and gravel aquifers outside the SSA area; (2) bedrock aquifers; (3) 
reservoirs; and (4) free-flowing streams and rivers. Due to low 
potential yields and poor water quality, bedrock aquifers are not a 
viable alternative source of drinking water. Similarly, nearby water 
supply reservoirs lack enough additional capacity to serve as viable 
alternative drinking water sources. Finally, for over 70 percent of the 
communities that are near enough to use sand and gravel aquifers 
outside the SSA area or free-flowing streams and rivers to deliver 
drinking water of the same or better quality, it would be economically 
infeasible to do so.
    (3) Contamination of the Mahomet Aquifer System would create a 
significant hazard to public health for east-central Illinois. The 
Mahomet Aquifer System is a significant water resource that is 
critically important to the safety and economic development of the 
area. It is the primary source of drinking water for over 100 
communities and tens of thousands of rural homeowners located within 14 
Illinois counties. In addition, the Mahomet Aquifer System furnishes 
water to many self-supplied agricultural, industrial, institutional, 
and commercial users that rely upon it for cooling, process water, and 
row-crop irrigation, providing an estimated 170 mgd to these users.

IV. Information Relevant to the Designation

    The information referenced to make this designation is available to 
the public and may be inspected during normal business hours at EPA 
Region 5 Library, 77 West Jackson Boulevard, Chicago, Illinois 60604. 
In addition, documents related to this designation are available at 
area public libraries listed above.

V. Project Review

    Following publication of this determination, ``no commitment for 
Federal financial assistance (through a grant, contract, loan 
guarantee, or otherwise) may be entered into for any project which the 
Administrator determines may contaminate such aquifer through a 
recharge zone so as to create a significant hazard to public health, 
but a commitment for Federal financial assistance may, if authorized 
under another provision of law, be entered into to plan or design the 
project to assure that it will not so contaminate the aquifer.'' 42 
U.S.C. 300h-3(e). EPA may review any such proposed projects and, where 
possible, make suggestions or recommendations to plan or design the 
project to ensure it will not contaminate the aquifer system so as to 
create a significant hazard to public health. Proposed projects that 
are funded entirely by state, local, or private concerns are not 
subject to SSA review by EPA.
    The project review area for this SSA consists of the designated SSA 
area plus three watersheds adjacent to the designated SSA area that 
provide recharge to the Mahomet Aquifer System. These watersheds are 
the Sugar Creek, the Sangamon River near Fisher, and the Tributary to 
the Middle Fork Vermilion River. A map of both the SSA area and the 
project review area can be found at the locations listed above.

VI. Conclusion

    Today's action designates the Mahomet Aquifer System in east-
central Illinois as an SSA. The designated SSA area and project review 
area are located in the following counties in Illinois: Cass, 
Champaign, DeWitt, Ford, Iroquois, Livingston, Logan, Macon, Mason, 
McLean, Menard, Piatt, Tazewell, Vermilion, and Woodford. Maps 
depicting the designated SSA and project review areas are available to 
the public at the locations listed above.

    Dated: March 11, 2015.
Susan Hedman,
Regional Administrator, Region 5.
[FR Doc. 2015-06365 Filed 3-18-15; 8:45 am]
BILLING CODE 6560-50-P