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y n u ~~ ~~ (Page 3) NINE ID / OR PROSPECTING ID ~ N-79-216-HR INSPECTION DATE 11/12/96 INSPECTOR'S INISIALS ACS through to serve as a spillway. The embanJ®ent appears to have been pushed into place or dumped in place nt the angle of repose, and it dcee not appear to have been compacted. There are trees and shrubs growing in the emban]®ent and in the pond. If this pond ie going to remain a component of the storm water management system at the Deer Creek quarry, Lt will have to be completely redesigned and reconstructed (see PB f4 on the last page of this report) . Item i5 Naintenance item /5 is related to the routing of Wildcat Gulch into a culvert under the topsoil stockpile. The operator has stated that flows in Wildcat Culeh that would exceed the flow capacity of the culvert would overtop the channel and sheet flow across the terraces to the Wildcat Gulch channel below. Haaed on observations made during this inspection, it appears that flows that exceed the carrying capacity of the culvert would submerge the culvert entrance and back up into the gulch. This being the case, the culvert entrance should be stabilized by installation of wing walla or placement of riprap. A trash rack also needs to be installed at the culvert entrance, and the culvert entrance area needs to be cleared of brvsh. in addition, the culvert outlet location needs to be identif ied.~ We searched for a culvert outlet in the field, but could not find it. Once the culvert outlet has been identified, it needs to be evaluated for carrying capacity and stability (see PB /4 on the last page of this report). Genera l__Obeeroatione Related to Site Runoff 1. Noet of the runoff from the upper, undisturbed portions of wildcat Culch ie routed to the culvert under the topsoil stockpile. 2. There ie a berm rvnninq across Bench f3 that serves to detain runoff from the upper portions of the quarry. The silt depoe ited behind this berm indicates that it has been effective in settling solids from the runoff. 3. The runoff from the upper quarry that reports to the bermed azea located on Bench f3 flows primarily ae sheet flow then into gullies developed in the roads that are on ramps between the upper quarry benches. These gullies eroded into the road surfaces exit into a wedge of crusher fines piled on the uphill end of Bench #3, and a large erosion gully has eroded this pile of fines. Dtility Pole It was observed that there is a utility pole installed at the crest of the highwall above the scale house. The presence of a steeply dipping fracture oriented sub-parallel and just interior to the highwall has caused sloughLnq of the highwall adjacent to the utility pole location as evidenced by the rvbble pile at the base of the highwall and the fresh eearp on the highwall. The stability of the utility pole is threatened by continued sloughing. In accordance with Section 34-32.5-115(4)(e) of the Reclamation Act for the Extraction of Construction Materials, the operator moat secure an agreement with the owner of the utility pole that the operator will provide compensation for damage to the pole, or the pole moat be relocated to a stable Location or otherwise stabilized. Summary and Conclusions Stormwater flows through the Deer Creek quarry site need to be evaluated and these flows and the potential for discharge of suspended solids to Deer Creek need to be characterized. Based on this evaluation, a storm water management system needs to be designed and installed that is capable of containing suspended solids on site that may 6e generated during the 10- year, 24-hour storm event. It is likely that a combination of storm water management structures will be required for the Deet Creek Canyon Quarry, and that the management plan will call for efficiently routing runoff from the undisturbed area above the quarry through or around the disturbed azea, installing a aeries of ditches, cross drains, and detention structures within the disturbed area to minimize erosion and to settle solids out of the runoff, and reconstruction of the settling pond at the base of the quarry to provide a final polishing step prior to discharge of storm water to Deer Creek. The operator needs to complete such an evaluation and put together a management plan for Divleion review and approval (see PB f4 on the last page of this report). once the Division has approved the storm water management plan, specific deadlines will be established for implementation.