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M*. Midnel Goulay Dccian ofMvaerats and Cxdodv Jmu(ary 18, 1999 Page 11 Comment 34 -Page 112 of Tab 17 states that two farmed fields above J. R. (sic) Temple Reservoir No. 2 are subimgated, with no mention of flood imgation above the reservoir. Exhibit 16-1 (Water Rights) indicates flood imgation of fields in Hubberson Gulch from the Hollatz Ditch No.l and No.2. This information is also discussed in Tab 16, and the Gelds appear to be located in alluvial valley floors. 7lx pro&ibte H}rl>dogrc Cmtsct7rmt~s scrtirn rrocst Ee tgx(atei to irdtde tlx possif~e aptss ojvxmnsad srrrfao= viuersalcrity cot dx irrgatel frelds rmd possiblealluctnl uxlleyflaon lcratef vt Hul~erst~t Gtdth. Tab 17, Probable Hydrologic Consequence, has been updated to include the following (Insested after paragraph 2, page 109, Tab 17J Surface water monitoring locations within Hubberson Gulch include three stations (WSH17, WSH7 and WSHF]). Available data suggest that the upstream station may act as a gaining stream reach for minimal groundwater discharge from the 2003 pit area. Station WSH17 may also receive groundwater and spoil discharge from the 2003 pit area. Downstream stations WSH7 and WSHFi will receive grotrndwazer and spoil discharge from the entire Seneca Il-W South area. Results from the surface water loading calculations in Hubberson Gulch suggest a posunirung TDS of 1,888 me/L (WSHFl). The downstream concentration represents aloes-flow percentage TDS increase of approximately 95 percent. However, aher mixing with surface water from Watering Trough Gulch, the resulting TDS increase to Dry Creek is significantly decreased (see Table 42a, Summary of Projetted Loading Impacts to Surface Water in the Seneca II-W South Area from Spoil Discharge). (Inserted after paragraph 3, page 112, Tab 17J Native rangelands and native subimgated wetlands characterize all upper portions of Hubberson Gulch. However, there are several small hay fields in lower Hubberson Gulch located in the Sections 16 and 21, Township SN, range 88W, from approximately r/+-mile southeast of the Smith Ranch to the confluence of Hubberson and Watering Trough Gulches. The fields are approximately 26 acres in area and are flood irrigated with surface water diverted from Hubberson Gulch through Hollarz Ditch Numbers 1 and 2. The hay crops are composed of mixed hay grasses with a production rate of approximately 2.5 tons of grass per acre per year. The fields Ge between surface water monitoring stations WSH17 and WSH7. Therefore, a water quality projection, which represents the mean TDS value of these stations, is utilized to project potential crop reductions due to increased TDS in Hubberson Gulch surface water. As shown in Table 7-50, Comparison of Surface Water QuaGry to Imgation Standards), irrigation standards at site WSH7 have been exceeded for six analyzes in surface water samples, including total aluminum, field pH, total iron, dissolved and total manganese, total molybdenum, and total sulfate. Per paragraph 2 on page 144 of Tab 7, surface water monitoring stations in Hubberson Gulch have a low sodium_-high salinity hazard, and are marginal}y suitable for irrigation of tolerant and semi-tolerant crops. The grass hay in the fields is not specifically designated within the vegetation survey, because the Fields are outside of the permit boundaries of both Seneca II-W and Seneca II-W South. However, because a vast majority of hay produced in R9utt County is not a specific grass species but rather a mixture of smooth brome, timothy, orchard grass and Gamson foxtail barley (cumulatively referred to as "odawrrhay", Banta, 1988), this designation will be utilized to estimate potential crop reductions to the fields as a result of "urnst-care" salinity increases in Hubberson Gulch from upstream mining activities at Seneca II-W South. Variables are provided in Banta (1988), Saw (1972), IppoGto (1992), and previously in this doatment for barley, orchardgrass,