R2012-118 AUTHORIZING GRANT AGREEMENT WITH STATE OF ILLINOIS

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Project Abstract [not m. �:han 350 characters, approx. 50 words] A0.C�1M'L1ti+ The project will truck 13,310 cubic yards of Lake Decatur dredge sediment from the City of Decatur's settling basin to a City owned closed landfill. Sediment will be spread to a 9" thickness to supplement the landfill's 6" topsoil cover so that 11 acres of native prairie grass and forbs can be established for bioenergy crop production. Project Description [if more space is needed, please attach additional project description to application] BACKGROUND AND DESCRIPTION The City of Decatur has owned and operated Lake Decatur as a public drinking water supply reservoir since the 1920s. Since then, two large scale hydraulic dredging projects have been undertaken and paid for by the City: 1993 -1994 1,294 acre feet of lake sediment removed from Basin 5 2005 - 2011 1,598 acre feet of lake sediment removed from Basin 6 The City also plans to dredge 1,945 acre feet of sediment from portions of Basin 1 from 2012 — 2014. The main benefits of these major dredging projects are: 1. Increase the water storage capacity of Lake Decatur by 4,837 acre feet. 2. Reclaim areas of the Lake that have regressed into mud flats of extremely low environmental, economical and societal value. 3. Enhance the Lake's outdoor recreational values including boating, fishing and swimming. 4. Enhance the Lake's biological diversity and improve water quality. 5. Significantly increase the recreational and aesthetic value of-several publically owned parks and natural areas adjacent to the dredged locations. 6. Create upstream sediment traps to reduce sedimentation in main body of the Lake. The traps also provide a cost effective way to perform future maintenance dredging. 7. Enhance the Decatur area economy by drawing more regional fishing tournaments to Lake Decatur. S. Increase local government real estate tax revenue due to the increased real estate values of property adjacent to the dredged locations. The dredged material from the Basin 5 and Basin 6 projects has been/is being pumped and stored to a City owned 397 surface acre settling basin located in Oakley Township near Decatur. "Limited quantities of the dredged sediment have been used throughout Macon County for agricultural farm ground drainage improvements, crop enhancement, landscaping and horticultural improvements. A large quantity of the sediment was used to raise the height of the settling basin berm in 2004. See the enclosed 2005 document titled "Potential for Beneficial Use of Lake Decatur Sediment" by the Agricultural Watershed Institute for more detail. The City also owns and maintains an 11.3 acre closed landfill named the'Corley Landfill. The site was used to store excess lime residual (primarily calcium carbonate) from the City's drinking water treatment plant. Final closure and post closure maintenance activities were approved by the Illinois Environmental Protection Agency in 1995. The landfill impermeable earthen cap is 2'2" thick with a 6" topsoil cover. The vegetative cover consists of Kentucky bluegrass, perennial ryegrass, creeping red fescue and spring oats. Due to its highly visible location adjacent to US Business Route 51, the Corley Landfill is an ideal site to promote the growth, harvesting and use of native prairie grasses and forbs as a bioenergy fuel source. The Agricultural Watershed Institute, a not for profit institution based in Decatur, has been conducting work for the past two ,years to promote the use of prairie grasses and other plants on marginal farm ground to be harvested for alternative energy sources. 214' ,