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002902 . . was observed to have a negligible flow). The remalnlng 58 metric tons per day were due to saline groundwater inflows, irrigation return flow, and other non-point contributions (see Table 3). Although TDS concentrations at most sampling locations were generally twice as high during the "low flow" period as during the "high flow" period, the greatest salinity load in the White River occurred at "high flow" during Spring runoff (Table 3). During this period, the salinity load increased from 32 metric tons' per day near the headwaters (NF-1B) to 922 metric tons per day at Rangely (WR-l). This great increase is due primarily to leaching of dissolved minerals from the exposed river banks during periods of "high flow". Sampling on Milk Creek revealed these same general trends during each flow period. Specific conductance (conductivity) measurements were made at all locations and can be compared with TDS concentrations for each location. Except for Yellow Creek, conductivity values in the White River drainage averaged generally less than 1000 ~mhos/cm, ranging from 90 ~mhos/cm near Trappers Lake to 790 ~mhos/cm near Rangely. . . . . Suspended Solids Total suspended solids (TSS) concentrations and loads were, as expected, much greater during Spring runoff than during the "low flow" study (see Table 3 and Fig. 9). Concentrations averaged generally two to ten times higher during Spring runoff (maximum concentration of 620 mg/l at WR-l), while loadings were as much as 50 times higher during runoff than during the "low flow" period (maximum load of 2432 metric tons per day at WR-l). Part of the reason for the high suspended solids concentration and load at Rangely (WR-l) during Spr~ng runoff was that Douglas Creek was contributing approximately 1.42 m /s of extremely muddy water to the White River just upstream from Rangely. However, since Douglas Creek was not included in the sampling program, no chemical samples were obtained. The recommended mean TSS criterion of 25 mg/l for fish and wildlife protection was exceeded during Spring runoff at all sampling locations on the White River below Meeker and in Yellow Creek, Little Beaver Creek, Coal Creek, and Milk Creek. During "low flow", TSS concentrations still averaged above the criterion level in all these streams and in the White River below Yellow Creek (RM 111.0). The data in Table 3 appears to show good correlation between measured turbidity values and TSS concentrations, as would be expected. . . ! . Common Mineral s . Concentrations of the common minerals (calcium, magnesium, sodium, potassium, and chloride) were generally highest during the "low flow" period when groundwater recharge constituted a larger portion of the total river flow. The profiles for sodium and chloride concentrations shown in 28 . '1 ;'-