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i flow (baaePlor) conditions dominate. Total avapendad aolida (TSS), total aluminum (Ali) and total iron (Far) were at generally higher concentrations at both sites during the spring enoxmelt period, in comparison with observed concentrations of these three constituents during the baeeflox months (August - November). Nitrate (NO3) lavala at both sites generally increase measurably at both aitea after spring enoxmelt ends and the growing season progresses, suggesting that up-drainage return flow Prom irrigated, fertilized fields contributes to nitrate lavala in the reach o£ Dry Creek in the vicinity of the Loadout during the baseflor period (August - November). Concern xaa expressed by CDMG regarding the proximity of the downstream monitoring site (HGSD2) to the Loadout. As a consequence, a ner, proximate doxnatream Bite (HGSD3) was aetabliahed on 10/21/93. A comparison of aur£ace water quality data collected at stream monitoring eitea HGSD1, HGSD2, and HGSD3 during 1993 is presented in Tables 7-9. With the exception of alkalinity, N03, and A1, there is a progrea9ive doxnatream increase in the concentrations of the major ions and trace metals between Sites HGSD1 and HGSD2. Site HGSD3 is intermediate betraen the two, but located closer to HGSD2. Constituent concentrations at HGSD3 ware approximately 70 to 90 percent o£ those measured at HGSD2 on the same date. • Trilineer diagram and Schoeller plots for the three stream sites era shown on Figures 7- 8 to 7-10 and 7-11 to 7-13, respectively. Aa xaa previously mentioned in the ground water diacuseion, the concentrations oP R and C1 for all pre-1993 samples ware estimated using meq/1 percentages determined from the averaged poet-1993 analyaea which did include R and C1 concentrations. The cation and anion points for HGSD1 and HGSD2 show some scatter, but there are no trends to the scatter. The trilinear and Schoeller plots for HGSD1 indicate the 5/5/85 sulfate value is erroneous. Historically, atraem site HGSD1 has exhibited a NgNaCaSO~ or NgCaNa30~ water type and stream Bite HGSD2 hea shown either a MgNaSO~ or MgNaCaSO~ water type. The new doxnstraem monitoring site (HGSD3) also exhibits a MgNaSO~ water type. Considering the concentration increase trend doxngradiant Prom the Loadout, the more proximate doxnatream site (HGSD3) should be appropriate for use in assessing any stream rater quality impact tranda. Perusal of the long-term data for sites HGSD1, HGSD2, and HGSD3 (Tables 7-5, 7-6, and 7-7) indicates there era no discernible increasing concentration tranda Por any of the chemical parameters. The data indicate that the Loadout has not caused any measurable impacts on the Dry Creak atraem water quality. • /ZN-o/ 22 Revised 2/9H