## 3 Results and Discussion
### Improved Application of Brine  
The high efficiency of the magnesium-chloride solution (Brine) in dust emission suppression because of vehicle transportation was already reported [18; 24]. The results of this study indicate clearly on the high efficiency of the magnesium-chloride solution in dust suppression because of wind erosion in calcareous soil bed in arid climate. The magnesium-chloride solution (Table 1) provides soluble salts to the soil that act as a cementing material for the formation of soil aggregates and soil structure [25]. Moreover, its hygroscopic property allows absorbing water from the atmosphere, even in low atmospheric humidity, agglomerating the fines and holding the aggregate matrix together through suction forces [18]. The existence of water enables the cohesive forces between the soil particles, in particular the clay-sized particles [26]. In turn, the higher soil water content, the lower wind erosion and dust emission because of the inter-particles connections and larger aggregates that are more resistance to the wind shear stress [14]. Moreover, the Brine hydro \begin{table}
\begin{tabular}{c c c c c c c} \hline \hline
**Wind Velocity (m s\({}^{-1}\))** & **Control** & **Brine** & **Lignin** & **Resin** & **Bitumen** & **PVA** \\ \hline
4.0 & N/A & 57.7 & 0.0 & 0.0 & 0.0 & 0.0 \\ \hline
6.5 & N/A & 91.7 & 0.0 & 0.0 & 0.0 & 0.0 \\ \hline
8.0 & N/A & 97.3 & 0.0 & 0.0 & 0.0 & 0.0 \\ \hline
9.5 & N/A & 99.0 & 0.0 & 0.0 & 14.3 & 3.9 \\ \hline \hline \end{tabular}
\end{table} 
Table 4: The efficiency (%) in dust-PM10 emission recorded two weeks after the dust control application on the unpaved road with 446 fides of the quarry Euclid Trucks. The dust suppression efficiency (%) was calculated as a ratio in dust flux between the treated road section and the control (no-treatment) road. \begin{table}
\begin{tabular}{c c c c c c c} \hline \hline \multirow{2}{*}{**Wind Velocity (m s\({}^{-1}\))**} & \multicolumn{6}{c}{**Dust-PM10 Emission Flux (mg m\({}^{-2}\) s\({}^{-1}\))**} \\ \cline{2-7}  & **Control** & **Brine** & **Lignin** & **Resin** & **Bitumen** & **PVA** \\ \hline
4.0 & 0.36 & 0.15 & 0.30 & 0.18 & 0.27 & 0.18 \\
6.5 & 2.95 & 0.24 & 0.87 & 2.14 & 0.45 & 0.48 \\
8.0 & 10.98 & 0.30 & 5.26 & 4.42 & 0.66 & 0.94 \\
9.5 & 36.54 & 0.36 & 13.71 & 17.16 & 1.41 & 1.98 \\ \hline \hline \end{tabular}
\begin{tabular}{c c c c c c} \hline \hline \multirow{2}{*}{**Wind Velocity (m s\({}^{-1}\))**} & \multicolumn{6}{c}{**Dust Suppression Efficiency (\%)**} \\ \cline{2-7}  & **Control** & **Brine** & **Lignin** & **Resin** & **Bitumen** & **PVA** \\ \hline
4.0 & N/A & 57.7 & 14.8 & 49.6 & 25.4 & 50.7 \\
6.5 & N/A & 91.7 & 70.4 & 27.4 & 84.7 & 83.6 \\
8.0 & N/A & 97.3 & 52.1 & 59.8 & 94.0 & 91.5 \\
9.5 & N/A & 99.0 & 62.5 & 53.0 & 96.1 & 94.6 \\ \hline \hline \end{tabular}
\end{table} 
Table 3: The calculated PM10 emission fluxes from the unpaved roads in the first field wind tunnel experiment are presented in the upper part of the table. In the lower part of the table, the dust suppression efficiency (%) calculated as a ratio in dust flux between the treated road section and the control (no-treatment) road. a byproduct, a waste material, from industrial production. In Israel, this Brine is available by the production process of potassium (K) from the saline Dead Sea. The use of waste materials is important in sustainable environment perspective. The recommended application of the Brine is wetting the soil surface at the rate of 1.5 L m\({}^{-2}\), based on the very high efficiency of the Brine to suppress dust emission in the calcareous soil. It was assumed in this study that the application rate can be reduced and still keep on high efficiency. In order to test this, five samples with different rate of Brine concentration (amount of solution in the soil) were prepared for laboratory experiment: 1.5 L m\({}^{-2}\), 1.2 L m\({}^{-2}\) (that is 80% of the recommended rate), 0.8 L m\({}^{-2}\) (60%), 0.5 L m\({}^{-2}\) (40%), and 0.3 L m\({}^{-2}\) (20%).