Sink Hole

[wayne soper]

1950's ranch
1/3 basement , crawlspaces on both sides.
left side crawl has sink hole
3 feet deep by 12 feet across.
Appears to have been holding water at some point but was dry at time of inspection. Sand at bottom.
Foundation footings visble.
Very little dirt or debris in the crawl that would indicate owner digging.
Small opening in upper foundation wall that could have been a leak area fro rear yard although grade slopes well away in this area.
Possible buried tank at same location at rear wall. May have been sand filled but yet to be determined.
Any thoughts would be appreciated.

[Jerry Peck]

left side crawl has sink hole
3 feet deep by 12 feet across.

Any thoughts would be appreciated.

I think you covered it pretty well with "sink hole".

I would be concerned with the footing you are seeing as the soil under it is most likely gone, having been replaced with the soil which collapsed into the hole. That means the soil under the footing is not virgin undisturbed soil nor is it compacted in any way.

Which means there may not be any support for that footing, at least no support like what was intended.

[John Dirks Jr]

How thick is that slab? It looks very thin. Is less required because its a crawl? I mean, some crawls are just dirt but if there is a slab, are there standards?