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Area 8 <br />The dugout pond contains the run-off from topsoil stockpile #1. The drainage area for the dugout <br />pond is comprised predominately of lush orchard grass. Of the 0.4 acre area, an estimated 0.3 <br />acres is lush grasses with ground cover that is almost 100%. The south facing slope of the topsoil <br />pile is relatively bare with fair ground cover. Two curve numbers were selected for this area. A <br />curve number of 74 was selected for 0.3 acres of lush vegetation and a curve number of 82 was <br />selected for the 0.1 acre south facing slope. <br />Area 9 -Small Area Exemntion #1 <br />Area 9 is the outslope of the facilities pad, the loadout facility and the railroad spur track. This <br />area encompasses 3.2 acres. It would be very difficult to construct a sediment pond below this <br />area to collect the runoff from it. For this reason, alternative sediment control is provided as <br />shown on Map 14. There is no reason to suspect this area contains acidic, toxic or alkalinity <br />forming materials. Drainage from the outslope area would flow down the face of the <br />embankment and then routed along the toe of the embankment into one of two culverts. Run-off <br />from the track area will generally flow west on the north side of the tracks to one of four culverts. <br />In all cases, run-off will pass through alternate sediment control such as straw bales, straw <br />waddles or siltfence before it flows into the culverts. <br />Sampling points SAE-1 through SAE-4 were established at the original culvert outlets to confirm <br />that run-off from the small area exemption meets the effluent limitations. With railroad <br />construction in 2000, SAE-2 was eliminated. See Map 14 for details. Before samples were <br />collected, it was to be determined if irrigation water is causing or supplementing the flow at the <br />SAE sample point. If ittigation water is influencing the flow, then upstream water samples would <br />be taken at one of the sample points shown on Map 14. Upstream irrigation water samples would <br />be analyzed for settleable solids. If available, samples from the sample points would be collected <br />during a significant precipitation event or during snowmelt to confirm compliance. After two <br />samples have been taken that confirm compliance, no further sampling would be performed <br />unless further sampling is required by the Division. Samples not influenced by irrigation water <br />will be in compliance if they contain settleable solids levels of 0.5 ml/1 or less. Samples <br />influenced by irrigation water will be in compliance if they contain settleable solid levels of no <br />more than the settleable solid level contained in the upstream imgation water sample plus 0.5 <br />ml/1. <br />Item # 2 of this Exhibit 9 provides a summary of SAE compliance demonstrations. SAE sample <br />point No. 3 was sampled on 9/10/1992 and SAE sample point No 2 was sampled on 5/25/1993. <br />The results of the sampling indicate compliance with the effluent limitations. <br />Sediment Pond <br />The run-off calculations presented on pages 5, 7 and 8 show that the sediment pond must contain <br />0.48 acre-feet of water, 0.05 acre-feet of sediment and the emergency spillway must be designed <br />to pass 8.62 cfs. The existing sediment pond has a water capacity of 0.84 acre-feet and a <br />sediment capacity of 0.14 acre-feet. See Map 7, Sedimentation Pond Design. The capacity of the <br />sediment is therefore adequate to contain the design event and the calculated sediment loading. <br />-3 - <br />Rcv. August 2005 <br />TR-9 <br />/` PPROVE/~ <br />$'/26/65 <br />