Residual‐Wax Soil Treatments for Water Harvesting

Paraffin wax is being used as a soil treatment to increase the water runoff yield from precipitation. However, the increasing costs of petroleum products and occasional treatment failures prompted this laboratory study to improve treatment‐weathering resistance, decrease wax application rates, and substitute residual waxes for the more expensive paraffin. Ten residual waxes and two paraffin waxes were applied to Tremant soil (fine‐loamy, mixed, hyperthermic Typic Haplargids) at three rates (0.25, 0.50, and 1.00 kg/m 2 ). Each wax contained three rates of antistripping agent (0, 2, and 4% by weight). Before the wax application, the soil was stabilized either by wet compaction alone, or by compaction followed by application of cellulose xanthate. The treated soils were weathered by alternately subjecting them to freeze‐thaw cycling, to erosion, and to water repellency testing. The laboratory results showed that the less costly residual wax treatments were generally more weather resistant than the paraffin treatments. Generally, the antistripping agent and cellulose xanthate improved weatherability of the waxes tested. Results also indicated that, with soil prestabilization and the addition of antistripping agent, the wax application rate for most waxes on soils similar to the one tested could be reduced to 0.25 kg/m 2 , which is one‐fourth to one‐eighth the currently recommended rate. The best treatments will be field‐tested to confirm these laboratory findings and to extend the use of wax treatments to other soils and climates.