A: I recall seeing an article in Concrete Construction about some kind of grout material you can pour into drilled holes in concrete and cause the concrete to crack apart so it can be easily broken up and taken away. I can't seem to find the article and nobody around here stocks anything like that for sale. Where can I get it?

B: You must be thinking of a silent, nonexplosive demolition agent. One such agent was described in an article that appeared in the April 1982 issue, page 366. Such products are based on portland cement and are used by mixing with water, pouring into 1 1/2-inch or slightly larger holes spaced 1 to 2 feet apart, and waiting about 10 to 24 hours. We know of two companies that currently manufacture the materials:

Construction and Industrial Supply
189 Cobb Parkway North B-3
Marietta, Georgia 30062

Sumimoto Corporation
Box 10141 Pacific Centre
Vancouver, British Columbia
Canada V7Y 1E9