Structural engineer pages added to basement project

I have added a new page to the basement project post. It contains three images of pages that the structural engineer gave me when he consulted me on digging under the foundation. He said it was very difficult to find any information on the topic, so hopefully these three pages will come in handy to someone. Obviously, if you actually do dig under your basement foundation, I am not liable if something goes wrong! This is not something that should be done without advice from a structural engineer.