Influence of In-Situ Scaling on Variability of Polluted Soil Erodibility Parameters

Middle and southern Iraq suffers from polluted soils due to crude oil, spilled on land, leakage from transmitting pipe networks, or petroleum products from refineries. Many researchers have studied pollution impacts on the soil in details, but there is a clear lack of investigation on the influence of crude oil on soil erodibility. Recent researches have investigated the influence of pollution on erodibility parameters, which include critical shear stress (tau(c)) and detachment factor (d(c)). The variability of d(c) and tau(c) due to different in-situ scaling has not been thoroughly established for polluted and unpolluted soils. Thus this research aims at investigating the influence of different in-situ scaling ratios (1: 1, 1: 30, and 1: 50) on variability of d(c) and tau(c) for polluted and unpolluted soils under controlled laboratory conditions, using Jet Erosion Test (JET), and tries to compare the three solution techniques (namely, Blaisdell's approach, depth scour approach, and iterative approach) to solve d(c) and tau(c) from JETs for polluted and unpolluted soils. The polluted soil samples have been prepared by submerging the soil surface with crude oil for 24 hours prior to testing. Results show that there have been statistical differences in d(c) and tau(c) between polluted and unpolluted soil samples on the dry side of water contents with no statistically significant difference of measured d(c) and tau(c) being observed across different in-situ scale ratios for polluted and unpolluted soils. All told, the study shows less variability of measured d(c) and tau(c) across different solution techniques, compared to previous study findings.