Has anyone seen this before?

[Patrick Harding]

We just cleaned a building with softwash and it cleaned up all the mold but there where some marks underneath. They don’t appear to be stains but more just weathering in the concrete surface. they are all over the building and I am hoping to be able to explain what they are to the property owner. There is a micro-crack in the middle and on either side the concrete is darker/ wet looking. Any insight would be appreciated.
Just to check I did try high pressure and also some f-9 barc with no effect.

 

[Art Oliveri]

Looks like Creosote

 

[Patrick Harding]

Looks like Creosote

I had to look that up, is creosote a tar like substance? I’m not sure if you can tell from the picture but I don’t think there is any substance on the concrete, its more like under the concrete and each mark has a small crack going down the center. Have you dealt with this before? or is there anything that can be done to it?

 

[Ron Musgraves]

Pollution , you near a freeway?

 

[Patrick Harding]

Pollution , you near a freeway?

It is right by a high way but the surface is totally clean. Looks like the concrete is a different shade. I think it is just from weathering but I wanted to double check.

 

[Ron Musgraves]

It is right by a high way but the surface is totally clean. Looks like the concrete is a different shade. I think it is just from weathering but I wanted to double check.

YEAH, its Damage from Pollution
HOW DID I KNOW?

 

[Patrick Harding]

YEAH, its Damage from Pollution
HOW DID I KNOW?

Is it something that can be lightened or cleaned?

 

[Ron Musgraves]

Is it something that can be lightened or cleaned?

YEAH a type of HIGH Alkaline Degreaser