Fig. 8. Measured, fitted and predicted B breakthrough curves for the sandy loam soil at pH 7 and 9, and water flow rates, q of 2.9 and 0.19 cm h^–1. Dashed line was calculated by the LE-NE model for the fast-velocity data at pH7 using the rate coefficient of Table 2 and solid lines were obtained by fitting the LE-NE model to the fast-velocity data at pH 7 and 9 (best-fit values f and ₀ are given in Table 6) and by predicting the slow-velocity data at pH 7 and 9.