Q.: We have a 32- by 120-foot earth-sheltered house built of precast prestressed slabs, with a 2-inch-thick cast-in-place deck over the slabs, coated with two coats of waterproofer, insulated with 4-inch polystyrene slabs, covered with polyethylene with only one seam, then covered with 2 1/2 feet of earth. Walls are reinforced concrete masonry. There is slight leakage on the backwalls, mainly where the precast slabs meet. Is it possible that the problem could be remedied without removing the earth?

A.: This may be a possibility depending on the nature of the leak. There is a good new and fairly simple method of repair by epoxy injection that does not require a pump. It may work if the masonry walls have been filled solid. The equipment and materials are sold by Ostarr of America, 623 South La Grange Road, La Grange, Illinois 60525.

Addresses of manufacturers of epoxy injection equipment have previously been listed (March 1977, page 135).