I know this topic is a bit of a political lightning rod, but I recently came across this video and was impressed with the innovative approach to constructing the foundations for the US Border Wall. I’ve seen the DeWind One-Pass Trencher used for cutoff walls before, but this is a great application of the technology. They essentially create a mass-mix soil-cement foundation block about 8 feet below grade by 6 feet wide just inches from the border. Then they come back and cut a key slot down the middle to pour concrete and embed the above-ground portion of the wall. Pretty slick. I wonder if there are other applications for this technology for wall foundations?