Kingston can post up a link for "Misty"with in depth expansive info for "her".
In this area we have a lot of issues with clay impregnated sand. It creates a lot of issues around expansion, hardening, and compression, all which can negatively impact a backstop. The sooner either Dave (local cheaper) has the opportunity the examine that backstop the better.
I like Kingston's work, but gee, with just my one PHD, I feel so like such an under achiever....and of course, that's reflected in his price.