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Table 5. Percentage of riverbank bordering mapped cover classes between sample stations U5 <br />and D5. <br />Upstream Downstream <br />Cover Class_ of Discharge of Dischar P <br />Riparian Shrub 13 20 <br />Immature Riparian Woodland 18 6 <br />Mature Riparian Woodland 2 21 <br />Herbaceous vegetation 0 6 <br />Riprap 47 23 <br />Cobble 19 19 <br />Eroded (vertical soil banks) 1 5 <br />100 100 <br />discharge point, and gradually decreased to close to ambient upstream values by the farthest <br />downstream station at D5 (Figure 4). The presence of the plume was also detectable to a lesser <br />extent by temperature measurements. However, the temperature measurements shown in <br />Figure 4 were also influenced by time of day and the gradual warming of the river water. The <br />field measurements were taken at the same time that water samples were collected, and it took <br />several hours to complete this task. This was more than enough time for noticeable warming to <br />occur. Measurements were started at the farthest downstream station, working upstream, and <br />this produced an upward drift in temperatures seen on Figure 4. The effect of the plume on <br />field pH measurements was less obvious. An upward spike immediately downstream of the <br />discharge can be seen in the October measurements, but is absent or muted in the March data. <br />We believe the downward spike in the March pH data just upstream of the discharge to be an <br />anomalous value unrepresentative of either the river water or the plume. Dissolved oxygen <br />measurements indicated that the water was saturated with oxygen throughout the system and <br />concentrations varied according to water temperature. A complete table of all field <br />measurements, including those taken of the discharge, is given in Appendix 5. <br />Analytical results from the water samples are shown for selected parameters in Figures 5 and <br />6. The patterns shown by the data within each season are consistent, with the October data <br />showing a greater plume effect than the March data. In fact, the sample for station D 1 <br />immediately downstream of the discharge point appears to be representative of the river water, <br />and we suspect that it was taken outside of the plume (the plume is very narrow at D1, so this <br />could easily have happened). The analytical data from the October samples appear to be <br />consistent with the conductivity field measurements. Results of laboratory analyses for all <br />water samples are shown in Appendix 5. <br />16 <br />