# Forum Home Renovation Concreting  Coloured concrete driveway stained during cleaning

## SoupNazi83

Hi 
I have a coloured concrete driveway at my house which I'm worried I may have ruined. I have someone helping me with odd jobs around the house at the moment and two days ago I asked him to clean the driveway with a 10% solution of hydrochloric acid. My intention was to seal the driveway after it had been cleaned. 
I told him to scrub the concrete with the acid solution using a brush and then use a pressure washer to clean and rinse away the acid. As far as I'm aware this is exactly what he did but it seems like in some places the acid has caused discolouration (image attached). 
Does anyone know where I've gone wrong and whether there's anything I can do to fix this?    
thanks 
John

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## Random Username

Essentially, the acid has reacted with the oxide colouring (hydrochloric acid loves oxidised iron pigments).  About the only sure-fire fix would be to paint it over with a paving paint. 
You could try evening it out, creeping up on it with maybe a 5% solution so it's not so fast and you can rinse it off when it seems to match, but that's about the only thing I can think of.  But if they just did a shake-on type of surface colour rather than concrete that's pigmented the whole way through then you risk removing all the colour.  I'd stick with repainting!

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## SoupNazi83

> Essentially, the acid has reacted with the oxide colouring (hydrochloric acid loves oxidised iron pigments).  About the only sure-fire fix would be to paint it over with a paving paint. 
> You could try evening it out, creeping up on it with maybe a 5% solution so it's not so fast and you can rinse it off when it seems to match, but that's about the only thing I can think of.  But if they just did a shake-on type of surface colour rather than concrete that's pigmented the whole way through then you risk removing all the colour.  I'd stick with repainting!

  
Thanks 
The colour is the whole way through; I'll try with some more acid 
John

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