Post Constrution Asphalt cleaning

We have been cleaning for a builder for the last six months. Every thing has been fine, but they now want a price to clean the asphalt in front of their townhouse's. Normaly this would be no big deal, but this site is very dirty with paint, caulking and drywall mud pressed in to the asphalt.

Do any of you guys know a better way to remove caulking from asphalt besides by hand? the caulking is silacone based and the paint exterior.