CHICAGOLAND UNDERFLOW PLAN (CUP)
MCCOOK RESERVOIR - GROUT TEST

Chicago, Illinois

ACT was awarded the grout curtain test cutoff contract through a Best Value Selection process (RFP) by the US Army Corps of Engineers Chicago District. The overall project initiative was to complete 2 separate test sections utilizing 2 separate drilling methods to install grout holes. The drilling methods were evaluated throughout construction utilizing borehole washing data, water testing data, grouting data, borehole imaging results, and borehole deviation surveys. The data and knowledge gained from the test program was used to design the remainder of the anticipated grout curtain for the McCook Reservoir.

Work included: overburden drilling and overburden casing installation, water powered DTH percussion rock drilling, rotary rock drilling, initial exploratory core drilling, borehole washing, bore hole imaging, deviation surveying, and final exploratory verification hole core drilling.

IntelliGrout®, a proprietary computer monitoring system was utilized for real‐time electronic monitoring and recording of the permeability testing and grouting. IntelliGrout® provides powerful analytical and graphical tools for production grouting analysis allowing the grouting program to be adjusted in real‐time. The data was uploaded weekly to the IntelliGrout® Website allowing all project participants access to the data remotely.

The permeation grouting perform on this project was completed in the underlying limestone bedrock to a depth of 420 feet deep, making this project one of the deepest grout curtains ever constructed in North America. Much of the equipment utilized for the project was custom built to reach the required depths for hole washing, water testing and grouting. The residual permeability of the 2 test grout curtains that were constructed was in the order of 1 Lugeon.

Client: US Army Corps of Engineers, Chicago District

Owner: US Army Corps of Engineers, Chicago District