Our Waterfurnace Geo system has a pond loop located ~250' from the house & the "figure-8" pipe loop has recently started to show above the water surface.I believe the pipe is 1 1/4"dia.. The installing contractor had originally sunk the loop (1999) with large cable ties & concrete blocks. I dug the backhoe trench that goes from the basement to the pond end. The cable ties have obviously broken & I want to re-sink the loop myself. The question is how? I've considered using Romex tied to blocks or sand bags placed on top of the loop. Sand bags might get some UV degradation, plus I don't have any of them. IDEAS??? Thanks!