2012-01-23_APPLICATION CORRESPONDENCE - C2010088 (3)

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There are two tributaries to the Colorado River that are associated with the Fruita Loadout. Reed Wash, a perennial stream with a drainage area of thirty square miles and which flows due to irrigation water and precipitation events, cuts through the middle of the permit area from northeast to the southwest. Loma Drain, also a perennial stream, handles runoff from precipitation events and irrigation water around the town of Loma to the northwest and flows basically north to south across the western edge of the permit and adjacent areas. CAM established upstream and downstream surface water monitoring stations on Reed Wash and Loma Drain. On Map 08, they are designated as US -RW and DS -RW for Reed Wash and as US -LD and DS -LD for Loma Drain. However, the Division noted that the downstream surface water monitoring site on Loma Drain was not entirely downstream of all of the planned disturbance. Therefore, at the Division's request, CAM established a lower downstream surface water monitoring site, designated as L -DS -LD on Map 08, about 1,500 feet downstream of DS- LD on Loma Drain. Appendix 3 contains the baseline surface water monitoring data for Reed Wash and the Loma Drain. Flow rates in both tributaries reflect the irrigation season with high flow rates in the second and third quarters while low flow rates were recorded in the first and fourth quarters. The baseline surface water data for Reed Wash show that a low flow rate of 11.5 cfs occurred in the first quarter of 2010 while a high flow rate of 176 cfs occurred in the second quarter of 2010. The data also show that there was no perceptible flow rate loss between the upstream monitoring station and the downstream monitoring station on Reed Wash. The same pattern for flow rates applies to the Loma Drain as well. Baseline surface water data for the upstream site US -LD and both downstream sites DS -LD and L -DS -LD show that high flow rates occurred in the second and third quarters while low flow rates occurred in the first and fourth quarters. The baseline data show that a high flow rate at 31 cfs at the US -LD and DS -LD sites occurred in the second and third quarters of 2010 and 34 cfs in April of 2011 at the L -DS- LD site. The low flow rate of 1.75 cfs occurred in the fourth quarter of 2010 for US -LD and DS- LD. Again, there was no apparent flow rate loss between the upstream, US -LD, and downstream, DS -LD, monitoring stations on the Loma Drain. Since the surface water monitoring dates for L- DS-LD are not the same as those for UD -LD, a direct comparison of flow rate loss could not be made. The baseline surface water quality data show the general inverse relationship between flow rate and values for total dissolved solids and conductivity. The data also show the general direct relationship between flow rate and values for total suspended solids. For the Reed Wash baseline surface water data, a high conductivity value of 4,300 µmhos /cm and a high total dissolved solids value of 3,950 mg/l occurred for the first quarter of 2010 when the flow rate was low while the high total suspended solids value of 274 mg/l. occurred in the second quarter of 2010 when the flow rate was high. For the Loma Drain baseline surface water data, a high conductivity value of 5,200 µmhos /cm and a high total dissolved solids value of 4,760 mg/l occurred in the fourth quarter when the flow rates were low while the high total suspended solids value of 508 mg/1 occurred in April of 2011 for L -DS -LD when the flow rate was high. 12