ABSTRACT
The extraction of gravel, as a constructional material, is an important economic activity in some countries. Pits are drained by mechanical pumping while extraction is continuing, but flooding follows after commercial working ceases. Some are used for recreational use, such as water-skiing, or as marinas, while others have been used as land-fill sites. The gravel pit discussed in this Appendix was, after gravel extraction ceased, allowed to flood. There was also some illegal dumping of land-fill.
