Hello all, I am located in SE Michigan and want to get off LP gas as my source of fuel. Natural gas is not really an option (well its a 23K option) so I have been researching GEO. I have a question regarding closed loop systems. How much does the ground soil effect efficiency? I essentially live on a gravel pit (think sand/gravel) so I have fantastic drainage which is great for not flooding a basement but not so much for GEO from what I have read. I mentioned this to Waterfurnace dealer but they seem to think that since its buried 6 ft I will be fine. Any thoughts? I have also looked at a cheaper solution (open loop by WellConnectGeo out of Alpena, MI) but just not sure I want to maintain two systems (new heat pump + existing 20 yr old furnace) and deal with potential water quality issues. My well pump is also 210' deep so cost to pump and upgrading pump is in my mind. I can package it all into the 30% rebate. Still on the fence regarding what system but want to act within next two years to get rebate.