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operations, access roads, and the mazble waste piles. There also exists a 10,000 gallon diesel fuel tank and asemi-trailer mounted diesel-electric generator on the site. No significant additions to facilities or roadways aze envisioned for Sierra's operations. The underground portions of the quarry receive water from faults in the marble, primarily in early summer. Water is stored underground in settling ponds and is used in the stone cutting operations for dust contro{ and cooling. During the spring and eazly summer high runoffperiods, excess water is drawn from the settling ponds at points where it is least likely to pick up sediments, then pumped out the south quarry entry (Entry No. 3) and duectly East over to Yule Creek. CYMC sampled the water and provided data to the Colorado Department of Health. Records indicate no water quality problems and none aze expected in the fitture. Flow from the quarry never exceeded 100 gpm (0.4 cfs) during pumping operations (late spring and early summer), so there should be no noticeable impact on Yule Creek from such discharge. With the exception of a very small amount at the extreme northwest part of the affected area, all stormwater that flows into the affected area fmds its way into and under the existing marble waste piles. The water exits at the toe of the waste piles at the north end of the property, then enters Yule Creek shortly thereafter. CYMC took measures to control sediment that might fmd its way down through the waste piles and into Yule Creek. Siena plans to continue and improve upon these efforts. The nature of the waste piles works to minimize any potential damage to Yule Creek. The marble blocks and the fines deposited in the waste pile are over 99 percent pure calcium carbonate, a material used to condition acid mine drainage at other sites. The pH of the water runoff from the waste piles tends to be slightly high (basic). Yule Creek tends to be acidic, so the result may be a very slight improvement in the overall quality of Yule Creek water. CYMC's filings report minor buildup of sediment in the sediment control structure it built at the toe of the waste pile at Outfall Point 001. At the time of the preparation of this permit application, snow hides most of the surface features outlined in CYMC's plan. Upon snowmelt, Siena will inspect the structures built by CYMC and assure they continue to perform their function. One structure installed by CYMC is a sediment control trap (hay bales) that may be located on an adjacent landowner's property (just north of Outfall Point 001). It may be located outside of the affected azea, and was appazently paced without permission from the landowner. If permission can be obtained, Siena will continue to utilize this trap. If not, Siena will control sediment at the property line with an appropriately sized sediment control trap and hay bale structure. A very small amount of stormwater may fmd its way into a ditch along the haul road just to the north of the main quarry portal. This portal slopes down into the quarry, so water does not flow freely from the quarry out through the portal. It is also the lowest entry into the quarry so water would need to fill the quarry up to this level before it would flow out of the quarry. Stormwater is allowed to flow along the private access road a distance of approximately ?00 feet to the north to a point where the water is allowed to percolate into the topsoil just above what is known as Quarry Town. Although none has been required in the past, if erosion begins to show up at this location, a water diffusion structure will be built.