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Climate More detailed climatic information can be found in Tab 8 of the permit application. The region is chazacterized by a semi-arid steppe climatic regime with cold winters and mild to cool summers. The prevailing wind is from the northwest (reversing at night due to southeasterly upslope winds). Average annual precipitation is 16 inches and the growing season in the region is approximately 94 days. Climatic information was collected from both Hayden Station, one mile away, and the Seneca II-W Mine, six miles south of the loadout. Surface Water HvdroloQy Surface water information is found in the following sections of the permit application: Tabs 7, 12, 13, 14, 15 and 16 and Exhibits 12-2, 12-3, and 12-4. A summary of this information is included here, below in the Description of the Operations Plan and in Section B, Item III of this document. Most of the permit azea drains to Dry Creek. A small, northern portion of the railroad loop drains directly into the Yampa River. Dry Creek flows into the Yampa River neaz the town of Hayden. Stokes Gulch, an intermittent stream, flows into Dry Creek just south of the rail loadout. Precipitation averages approximately 16 inches annually in the permit area and the volume of runoff is limited. Most runoff comes from snowmelt or intense thunderstorm events. Flows in Dry Creek have ranged from 0 to 126 cfs (cubic feet per second) upstream of the loadout to from 0 to 225 cfs downstream. Two sediment ponds handle runoff at the loadout: the Truck Loop Pond usually discharges during spring snowmelt; the Rail Loop Pond has razely dischazged. Stream flow in Dry Creek generally increases downstream although some sections aze ephemeral. During the growing season diversions of water from Dry Creek above the permit can significantly reduce and even periodically eliminate streamflow in the vicinity of the loadout, while at the same time return flows from surrounding irrigated fields can dischazge small volumes of water to Dry Creek below the loadout. The dominant cations in Dry Creek water aze: magnesium, calcium and sodium; the dominant anion is sulfate. The pH is generally around 8.2. The concentration of the major cations, total dissolved solids, and nitrate (possibly due to agricultural return flow) increase during periods of low flow (baseflow). Total suspended solids (TSS), aluminum and total iron increase during high flows. Average values for total dissolved solids (TDS) aze higher downstream than upstream of the loadout, with average values of 2,439 and 3,175 mg/1(milligrams per liter), respectively. Please see Section B, Item III of this document for a discussion of the probable hydrologic consequences (PHC) of the Loadout on surface water quantity and quality and