Oily residue, white foam and rust color in drainage ditch
Didn't get much help in the organic forum, I asked there first because I thought it could be related to application of milorganite.
Here's the original post, and below the update to it
I applied milorganite at the proper bag rate on my 13000sq ft lawn... In the sane timeframe I leveled out and fixed some parts of my drainage ditch in the front yard. (The ditch was graded improperly and held water for up to a week after rain) I used soil from the woods behind my house, the top layer was 1 ft of good black soil, then about a foot of sand, and then another foot of clay/sand mix. I mixed it up pretty well, and didn't notice any oil in the soil when I put it down.
After getting almost 5 inches of rain in two weeks, the drainage is much better, but can't be fixed until my neighbor fixes a high spot in his... But the ditch is now a rusty color and also had quite a bit of oily residue, like if you washed oil off concrete. I can see how the milorganite could cause some rust but not the oil... Any ideas? New to this
Now, there is white foam forming in the ditch , every time the sprinkler hits it it all goes away, similar to popping bathtub bubbles - but it's back the next day...
What could be causing this? It's a subdivision and we see tons of rain so I doubt it just all of a sudden washed off the road when it never had before. No cars park near there that would've leaked oil either