Lime Stabilizing soils. (What is that white powder?)

Lime modification/stabilization is typically used to dry or stabilize over-moist clay based subgrade soils to allow follow on work to proceed quicker. There is some experiential evidence that it actually improves "strength" of the subgrade although that has been hotly contested by some engineers. It is basically a Lime Kiln Dust (powdered cement is sometimes substituted if the soils contain too much sand, at a much greater cost.) that is thoroughly incorporated into the top 12-16 inches typically and then recompacted with a sheepsfoot roller, regraded and then smooth-rolled before subbase is installed.
This job took place mid July of 2018 on a school parking lot expansion project in West Lafayette, Indiana.