I will tell a short tale of UST removal here in Northern NJ. I had a tank ca. 1957, 550 ga. properly abandoned in 2000- Local muni. permits pulled, tank opened and cleaned, AHJ signs off. Tank is filled with pea gravel, left in the ground, permit approved, all good. My house to be sold 13 years later. My feeling is pull the tank 'cause it will scare buyers. The neighbor also has a tank, ca 1955, 1000 ga. Neighbors tank taken out of service approx. 2008. Sits for that time. We join forces to remove both tanks at the same time as they are under our adjoining, not shared, driveways. My tank comes out soiled at exterior, rusty, full of wet gravel inside. All good. No evidence of leaks. His tank, within a few feet of mine comes out. It has a hole the size of a dime. 50K to start the cleanup on his side. $0 for me.