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0,,:0', Ju ... 0.... _ Buckhorn Creek, and Little Buckhorn Creek) and from USGS publications for South Fork Salmon River (Williams et al., 1989), Suspended-sediment samples were analyzed by standard procedures; mass of sediment was determined by weighing sediment after filtration and concentration is expressed in milligrams per liter. The percent of sediment at the sand-silt break (0.063 mm) was determined by weight. Concentration was convened to suspended-sediment load, Gs. in tons per day. was estimated by: G s = 0.00269568(c)(Q) (2) where C is concentration in milligrams per liter and Q is water discharge in cubic feet per second. The associated water discharge was determined by reference to the discharge rating curve for the station and the correspondiT1g stages during the sampling interval. . Example values of bedload and suspended-sediment load, with supplemental data, are shown for the USGS site, Boise River near Twin Springs, Idaho, in Table 5, and included for all sites in Appendix 4. For USGS sites, sediment data are routinely published in annual water-year repons by USGS. Slight differences in values of data reponed herein and in USGS repons may be attributed to: 1. Bedload data: use of the constant (0.38095238) herein rather than (0.381) USGS, but primarily due to checking all computations. Bedload-transport rates, t/d (tons per day), are expressed to three significant figures not to exceed two decimal places. 2. Suspended load data: USGS routinely rounds values of concentration to the nearest whole number and uses the constant (0.0027); herein, concentrations are determined to two decimal places and the used constant is 0.00269528. The effect of rounding the input (concentration) rather than the output by USGS is apparent for small concentrations. USGS would express concentrations of 1.49 and 1.51 as I and 2. While the actual difference is about 1.3 percent, rounding the input creates a difference of 100 percent. Suspended-load transpon rates, t/d, are expressed to three significant figures not to exceed two decimal places. 3. Total-load transport rates, t/d, presented herein are the arithmetic addition of bedload and suspended load, regardless of significant figures. The consistency in value reporting herein leads to reasonable further use (e.g., determining the ratio of bedload to total load). United Slates' Expert Report Disclosing Methodologies for Quantification of Organic Act Claims Consolidated Subcase No, 63-25243 31