Q.: Is there any experience with lead embedded in concrete? A lead-sheathed cable is intended to pass through a 10-foot length of concrete slab-on-grade. Will this cause any problems with the concrete?

A.: If there are no other metals in the concrete it shouldn't harm the concrete. As long as the slab stays moist, however, the calcium hydroxide in the concrete can attack the lead and within a few years the lead sheath could be disintegrated. The sheath could be protected from the concrete with a thick bituminous coating or by enclosing it in a polyethylene or other alkali-resistant plastic sleeve.