Wood River Deep Cut Off Wall Seepage Improvements
The project consists of improvements to the Wood River Levee system. The improvements are along the Lower Wood River Levee system between the intersection of L-143 / Enviroway and IL-143 / Wood River Creek, in East Alton, Illinois. GFA International has performed quality control (QC) testing of the Deep Cut Off Wall’s Self-Hardening Slurry (SHS). The deep Cut Off Wall with permeability of not less than 1 x 10-6 extending to depths of upwards of 140’ and 2,000 linear feet in length into the existing embankment with total thickness of 24”.
Challenges encountered during verification borings included compressive strengths as low as 28 psi. to overcome these challenges our highly experienced drillers utilized a triple barrel HQ wire line core barrel with low to water pressure. Additional challenges included extremely high hydraulic permeability test results from pre-placement sample in the range of 8x10-9 resulting in delays in the reporting. We also coordinated with our client and the Corp to reduce duplicative testing requirements and added additional equipment to get reporting of samples on time to meet the project schedule.