It is important to remember that sever damage can be caused when soft
brick is sandblasted by an amateur. The sand can actually gouge chunks
out of the brick itself, not only doing significant cosmetic damage,
but weakening the structural integrity, damaging the morter and allowing
moisture and insects access to your property as well.
One of the new products available to battle graffiti is the Baking Soda
Water Blaster. The hot water and baking soda combination is very effective
in removing certain types of graffiti. Along with its power, this technology
brings a hidden trap for the amateur graffiti remover. Although most
people consider baking soda to be a harmless substance, a baking soda/water
runoff destroys the pH balance in the surrounding soil and can destroy
landscaping sometimes requiring the soil be replaced! It might be hard
to explain to the boss how you saved money by renting this new technology
when thousands of dollars of custom landscaping is dead. Also, like
any other form of water washing equipment, the law requires retaining
pools so the materials washed from the surface (like lead-based paint)
are not swept into storm drains or allowed to filter into the ground
water.