In many homeowner's policies (that most don't read about coverage, exclusions, etc.) there are limits on flammable liquid amounts for home storage. Whether oil can be considered one-I'm not sure.
BTW-if 50 gallons of stored gas contributed to a fire-the fire department will know..........................
Just because you don't tell your agent-doesn't mean there isn't a PRINTED EXCLUSION.
If you have 50gl of stored oil on site and there's a fire, the fire Dept most assuredly will know and you may have a [duty to inform] them of such. As for the "don't ask, don't tell" approach.. I'm not sure that gets you out of your policies language, if any. Ignorance is not always a legal defense.
Fwiw, I'm in the 40gl range now and was just wondering today about it since it's policy renewal time. I am with the other guy leaning towards NOT bringing it up...I guess I was just wondering aloud about the possible implications, if any.