“Nobody will ever find that underground storage tank!”
What if its been filled properly??
Funny I didn’t think of that. I modified the report to incorporate that unlikely scenario. Thanks Sean.
Then there will be Documents supporting this. 
They must be cleaned prior to filling. The fill tubes are removed, interiors cleaned and then filled with sand, concrete slurry or foam. I have a similar set up. The darn fill tubes are remote on the exterior of the home but the 500 gallon tank is underneath the family room. It is not going anywhere.
I found this one last week under an addition. Shown my light down the open fill pipe and it reflected back at me. Also smelled of oil.
I didn’t open the cap. I wish I had. This is the first time in 5 years I’ve seen a UST beneath a home.
A GC friend of my did a custom home for a client upon which their was a UST, he did exactly what Sean said…fill it with sand and be done with it.
Several years ago I did a fix and flip, UST on the outside of the foundation…in that particular case the lender required it to be removed…once the tank was carefully removed I had to hire a soil engineer to verify that the tank had not leaked. I was fortunate, if it had it would have been costly to clean it up… from that point on I know longer do fix and flips with UST on the property.
Oh, when I say costly, I have another GC friend who does more commercial building… his tab to clean up several UST was over 100,000.00…ouch. He hired several lawyers but in the end the EPA prevailed.