Could this be an oil seep?

[SnoopLeon]

While the gang was doing some landscaping on our rural property, we uncovered a small spring. The water's mostly clear, but theres an oily film with a crude oil smell in the still areas. Normal? Or something to worry about?

 

[PipeDreamer]

I've seen that on rural land. The oily film is often iron bacteria or decaying stuff. Stir it; if it breaks up and stays that way, it's just biofilm and not a worry. If it sticks together and smells like gas, get your water tested.

Did the film break when you touched it? Are there any old tanks around?

 

[RedOnTheRig]

While the gang was doing some landscaping on our rural property, we uncovered a small spring. The water's mostly clear, but theres an oily film with a crude oil smell in the still areas. Normal? Or something to worry about?

A crude oil smell and oily film are not normal for a natural spring!
It suggests some form of petroleum contamination.
I'd say err on the safe side and contact your local environmental protection agency or department of natural resources right away to report it.
They can investigate the source and advise on next steps.
Don't use the water for anything until it's been tested and deemed safe!

 

[JonJon]

That's definitely something to keep an eye on. A little natural oil can show up in some springs, but a persistent crude smell and film could indicate contamination, consider testing the water before using it.