Chemical soil injection is done to reduce the ability of expansive clay soils to retain water, reducing "heave" in soil and the damage it can cause. The varying wet and dry cycles during the year cause the realignment of platelets in clay soils. This causes the soils to contract. Chemical injection allows excess moisture to be drained away by loosening the bond between molecules of water and the platelets. Chemical injections change the composition of the soil and reduce the expansion/contraction cycles. Injections into the soil are made by Power Jack with the aid of a high pressure insertion process, with equipment designed and produced specifically for chemical soil injection.