Concrete question

I recently had a concrete sidewalk poured. After the city left, it looks like "tunnels" were formed. This is the craziest thing I've ever seen. Is it possible there are concrete moles? Or some other kind of animal that could've pushed the concrete up? I've got a call into the city, only the good Lord knows when they will show back up.
Thanks
Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload
Keep calling the city, the Mole is probably a cheap contractor they will end up not not paying Unless he is : Connected ", but removal -redo may be the only answer
Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload
sounds like did not prep under the concrete and had air pockets formed and worked their way to the surface ?

Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload

HomeOwnersHub.com is a website for homeowners and building and maintenance pros. It is not affiliated with any of the manufacturers or service providers discussed here. All logos and trade names are the property of their respective owners.