Soil deterioration as influenced by land disposal of reject brine from Salbukh water desalination plant at Riyadh, Saudi Arabia

Impact of reject brine chemical composition on soils in Riyadh Saudi Arabia, was evaluated. Soil samples at three depths along transect on both sides of the pond were taken, in addition to, water samples from feed, product, reject and pond. Results showed that, the salinity of the brine reached up to, 5500 mg l− 1. The concentrations of soluble ions were exceeding the allowable limits in most water samples. The ratio of major ions and concentration factor was higher. The concentrations of heavy metals were in the allowable limits for drinking water standards especially, in the feed, and product waters. Results pertaining soil properties indicated that the soil pH, ECe values and, the concentrations of soluble ions were higher in soils closed to the pond. Also, the concentrations of heavy metals were negatively correlated with CaCO3 content and soil pH (expect for Pb; Zn; Cd and Cr), while it was highly correlated with clay content of the soil. Generally, higher ESP and ECe values in the studied soils can lead to lower permeability, poor aeration and consequently soil deterioration. © 2009 Elsevier B.V. All rights reserved.

Disposal of reject brine from Salbukh water desalination plant at Riyadh, Saudi Arabia, has a significant environmental consideration. The obtained results pertaining water analysis indicated that, the lowest values of pH, ECw, as well as the concentrations of soluble ions, were obtained for the product water. The pH values ranged from 6.9 to 8.3. The total salinity ranged from 407.2 to 80,009 mg l− 1). Also, the concentrations of Ca2+, Mg2+, Na+, K+, Cl−, and SO2− were exceeding the allowable limits for drinking water set by the Gulf Cooperation Council Countries [19] in most water samples. The ratio of major ions of feed water and reject brine was found to be higher. The respective concentration factor in the disposal ponds was also higher. Moreover, the concentrations of heavy metals were found to be in the allowable limits for drinking water standards. Results pertaining to soil properties emphasized the role of reject brine from Salbukh water desalination plant, on deteriorating the soil chemical properties. As the soil pH, ECe and ESP values as well as, the concentrations of Ca2+, Mg2+, Na+, K+, Cl−, and SO2− were so much higher in the upper soil layers especially in the soil samples that were closer to the pond. Higher ECe and ESP values of the studied soils can lead to lower permeability, thus, increase irrigation and rain water runoff, poor aeration and reduce leaching of salts from the root zone, consequently lead to soil deterioration.