It should be appreciated that the vibro methods generate considerably lower greenhouse gases, notably carbon dioxide, than the common conventional foundation solutions, and have, with the exception of vibro concrete columns, no detrimental impact on the groundwater. Cements and other cementitious materials are commonly used in vibro concrete column construction are very caustic and need to be included in the risk assessment and enforcement of safe working conditions on-site. The general application of the vibro concrete column method for a specific project to be executed in water-bearing soils follows the same rules of applications as any concrete pile foundation in such circumstances, and the choice of specific cements may have to be observed. As we have seen previously, vibro compaction and vibro replacement use only flushing water and compressed air and, when stone columns are built, inert backfill material (sand, gravel, or crushed stone). Should in specific cases the use of recycled concrete material pose economical advantages, not only the abrasion resistance and hardness of such materials need to be sufficiently high, but also their chemistry, when exposed to the groundwater should be reviewed to prevent unwanted groundwater pollution or any negative impact of the groundwater on the material chosen (see also Section 4.3.5).