Fresh water gate valve leak

You might be able to carefully cut away and scrape down the fitting flush with the tank and install a spin weld patch, then drill and spin weld a new fitting near the patch. The fittings and patches are really cheap. The problem is the the tools that hold the patches and fittings are size specific and each one it very expensive. They have 1/4 inch shanks and are to be chucked into a router to spin them at over 20,000 RPMs to melt the plastic fuzing them to the tank.

I have some links I can give for sources for the fittings and patches. I might even have sources for the tools. I'll post them later as I need to find them and I need to get some sleep my muscle relaxer is kicking in.