I have personally installed five such plugs. What hydrostatic head are you designing for?? What size drift dimensions?? Nature /geology of the rock?? What do you know about grouting because you're going to learn a lot before this project is over. Is the plug close to surface?? If so you have to consider hydrojacking potential....this is easily overlooked. Again what do you know about concrete pumping because youre going to become quite familiar with that as well.
