The grouting of an area in which (closely spaced) shallow holes have been drilled in a pattern in bedrock. This grouting has the effect of strengthening the upper portions of the bedrock and making it less pervious.
The grouting of an area in which (closely spaced) shallow holes have been drilled in a pattern in bedrock. This grouting has the effect of strengthening the upper portions of the bedrock and making it less pervious.