The East St. Louis project consists of the installation of a seepage control cut-off wall to protect from potential flooding. The original contract was awarded to Bauer Foundation Corp. (BFC) by the United States Army Corps of Engineers (USACE), St. Louis District, in November 2019. The project is located along the east bank of the Mississippi River, in the St. Louis area and was designed by USACE to guarantee the structural integrity of the levee by minimizing underground water seepage. The levee protects a vast area east of the river from potential flooding events that would be disastrous for the residents and the economy.

 

The single-phase cut-off wall was installed by a combination of a grab and a cutter which excavated under a self-hardening slurry designed by Bauer.

 

• Owner: U.S. Army Corps of Engineers (USACE), St. Louis District
• Client: U.S. Army Corps of Engineers (USACE), St. Louis District
• Execution: BAUER Foundation Corp.

 

Location

East St. Louis, Illinois, USA. Levee system on the east bank of the Mississippi River.

 

Scope of Work

Cut-off Wall: Total of approx. 618,000 square feet (57,400 m²) of single-phase cut-off wall self-hardening slurry, over a length of 4600 feet (~1,350 m) and to a maximum depth of approx. 143 feet (43.5 m). Including embedment in limestone bedrock.

 

Jet Grouting: Installed a single-fluid jet grouting cut-off wall under two culvert structures (utility tunnels) including a total of 167 jet grout columns, with inclinations varying from 0 to 30 degrees and to depths between 97 and 146 feet.

 

Geological condition

Sand, silt, clay, boulders, bedrock: limestone

 

Equipment:

• MC 96 with BC 40 Cutter
• MC 96 with DHG diaphragm grab,
• Klemm KR720 in jet grouting configuration.

 

Construction period: April 2020 – July 2022

 

Miscellaneous:

BFC, as the main contractor, was also commissioned with the provision of the necessary work platform, the installation and dismantling of the guide wall for the cut-off wall works, and the project quality control and laboratory testing.

After cut-off wall installation, the work platform was degraded, the clay cap material was placed, followed by topsoil, seeding and mulching. The same operations were conducted during the installation of the jet grouting barrier wall.

The location of the project poses a particular challenge: two vital utilities cross the alignment of the cut-off wall. In addition to this challenge, several other utilities cross the cut-off wall alignment or are located within the footprint of the project, including a gas line, water lines, high voltage transmission lines, and a conveyor belt used to load grains into barges on the Mississippi River. Bauer’s responsibilities include coordination with all utility owners and execution of the work within a series of complicated time windows at various locations onsite.