Inputs/Ideas on insulating dump bay compartment??

Thanks again for the advice. I temporarily installed a small heater in the bottom of the dump area that has a fan to help thaw the frozen line.
Got busy visiting my son & his wife and figured I'd chance the heater only until we get home and I can permanently insulate the plastic.

Great news is it's 4 degrees this morning and we have running water. That little heater did the trick.

Stay warm!! It's cold almost everywhere from what we're seeing on the news.