Hi,
I recently had a boundary wall replaced, and the builders were a bit messy with the mortar, and the short driveway is looking very messy. I was intending to get it off while it was fresh with a power jet, but a couple of days of hard frost later and the morter is well hard. I know from experiece that using a high-presurre with a "pulsing" nozzle is great at cleaning /removing but this is too vicious and breaks up the surface of the tarred driveway.
I will eventually be replacing it but is there a quick/easy way to remove the mortar off without affecting the softish tarred surface ? I recall reading that dilute Hydorcloric acid eats cement - but what would it do to tar ? ... and can this simply be washed down and diluted flowing into the street/drains.
-- Ham