2020-08-04_INSPECTION - C1981008 (2)

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July 28, 2020 C-1981-008/New Horizon Mine JHB HYDROLOGIC BALANCE - Rule 4.05 Drainage Control 4.05.1, 4.05.2, 4.05.3; Siltation Structures 4.05.5, 4.05.6; Discharge Structures 4.05.7, 4.05.10; Diversions 4.05.4;; Impoundments 4.05.6, 4.05.9; Stream Buffer Zones 4.05.18: The high intensity storm from the previous night, 7/27 into the early hours of 7/28, resulted in shallow pools of water in the bottom of many of the ponds. The only pond that was found to be discharging was Pond 13. ERMR directs CC ditch water into Pond 13, in addition to the French drains and spoil spring drainage, in order to manage discharge water quality. ERMR has created small catch basins up -gradient from Pond 13 to help slow runoff flow and drop out sediment in this temporarily graded slope. This proactive land management was effective in reducing the volume of sediment moving downslope and eventually depositing in Pond 13. Piping improvements, valve and meter installation had been completed at the inflow to Pond 13. Once the public comment period for TR99 has closed, the operator will be able to implement this revision. Pond 13 was holding a full pool of water, was relatively pond -weed free. Cattails remain near the pond inlet, but the main area of the pond was open water. Pond 13 was discharging 0.46 on the staff gauge. Effluent had a slight sulfur smell to it. The receiving stream, Tuttle Gulch was cloudier than the effluent from Pond 13. Some individual Russian knapweed plants were observed along the pathway to the primary discharge. Pond 16 had a shallow pool of water, well below the discharge point and well below impounding against the embankment. The in slopes to Pond 16 are fine, though vegetation is sparse. The area has been exceedingly dry. One small Tamarisk plant was becoming established at the base of the in slope of the emergency spillway. Frank dug it out by the roots during the inspection. The storm caused a gully to form in the swale in the irrigated Cropland field (Morgan property). Sediment was deposited in the ditch adjacent to BB road on the north side of the field. The Irrigation sprinklers were currently running. The field had recently been planted with the rotation crop, so vegetative cover was fairly thin with the establishment of the new crop. Some runoff had overtopped the county road and run over the road and washed some gravel and soil into the Enstrom pasture. The operator is already working with the farmer (JoEllen Turner) on the south side of BB road regarding mitigation efforts. Ms. Turner spoke with the inspector while we were looking at the sediment deposition. Ms. Turner said that she was satisfied with the mitigation plans that ERMR has discussed with her. She has also located areas that need repair after the storm event and notified the operator. ERMR will also need to contact the Enstroms on the north side of BB road regarding mitigation to the pasture. A minimal amount of material deposited in the Enstrom pasture, but it is still required to be addressed. The culvert on this north side of the Morgan property did not get blocked by sediment. Some sediment is present in the culvert inlet, but there was still open space for water to pass. The ditch and culvert will require cleaning. It appears that so much flow came down quickly with the recently replanted field that the system was overwhelmed. The irrigated cropland field had previously achieved Phase II bond release standards based upon the crop rotation. Pond 15 was damp with no standing water and no gullying into the pond. Pond 12 was damp and not holding a pool of water. Pond 9 is in the process of being reclaimed as approved in TR93. Material is being brought across 2700 road and backfilled against the southern slope at the south side of the pond. Water trucks were actively watering the work area to minimize dust. Number of Partial Inspection this Fiscal Year: 0 Number of Complete Inspections this Fiscal Year: l Page 3 of 11