Underground oil tank

[Sooyeon Kim]

Hi, Hope to get some help regarding my situation. I just got an accepted offer in jersey city and my inspector copper lines for oil tank in the basement. Oil tank is supposed to be in the front yard ((it's a brown stone building) but there is a pile of stones to see any fuel or vent pipes. The seller says that it was removed in late 70's or early 80's but cannot find the certificate. Requested to jersey city to find a record, but not sure if they keep the records this long. In this case, what should I do? Should I ask for the sweep test and if we can't find it, move forward? If it is removed more than 30 years ago, either we have a certificate or not, it's done deal, right? Would there be any chance in next 30 years that someone mandate the soil test even though there is no more tank left? Thanks and would appreciate any input. Soo