Identification of residue on pipe.

[Mahoogan]

Hello, I noticed the residue in the attached image on a pipe in a crawlspace. I could only see a few feet of the pipe exposed and didn't notice any other areas with similar characteristics.

Has anyone seen this before and know what the likely culprit is? I'm curious if it is corrosion resulting in a small leak.

Thanks

 

[Geofd]

if that's your drain its rotting out the culprit is age.....

 

[Mahoogan]

if that's your drain its rotting out the culprit is age.....

Thanks. I was afraid of that.

 

[Geofd]

if your at all handy you can change it its just very dirty the cast iron is probably very thin so you could cut it with a swazall and the correct cutting blades change as much of that pipe as possible if its all the same age its propabley close to the same condition you can use pvc in its place with the proper transition couplings