2015-10-08_REVISION - C1981041 (12)

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the hazard potential. On June 23`d, the DWR attempted to contact Mr. Fontanari but was unable to until the following day. However, on the evening of June 23rd, DWR stopped the water diversion off of Rapid Creek by disabling a diversion feature. On June 2411, I met with Tonya Hammond again at the South Portal to view the area. The seepage flow continued to be clear with no evidence of cloudiness or sediment, which would indicate a more serious condition. The flow at the portal area was measured by SCC at the flume and the flow was 33 gpm. The minimal seepage below the retaining wall on the north side of the backfill appeared to have decreased, with visible signs of the damp areas drying. The highest saturation point on the south side of the backfill had decreased, with visual signs of drying. No new saturation areas were observed on the backfill or the surrounding area. There has been no slumping or earth movement at the South Portal backfill identified to date. On July 23, 2014, the visual monitoring frequency of the discharge was reduced to once per week. DRMS has determined that conditions have stabilized and the flow from the french drain has returned to the level it was prior to the water application above the mine by Mr. Fontanari. The last inspection of the South Portal backfill occurred on August 11, 2014 and the flow from the portal was less that 0.1 gpm. As of August 12, 2014, the Division determined that weekly inspection of the South Portal area was no longer necessary and the potential threat of the backfill failing had diminished. Based on the Division's estimate, Mr. Fontanari applied as much as 166 acre-feet of water to the land surface above the South Portal backfill area and underground workings via the infiltration trench and Carey Pond. The calculation is based on 2 cfs flowing to the Carey Pond and as much as 1 cfs flowing in the new ditch for four continuous weeks. That equates to over 54 million gallons or an estimated 166 acre-feet of water applied to the surface. There is apparent communication between water applied to the ground above the mine and the outflow from the portal entries at the South Portal. There is, however, no substantial evidence indicating that water applied to the land at the Fontanari and Carey properties makes it way down to the Northwest Intake Pool and is then discharged via Outfall 016. This will require further investigation and understanding of potential subsidence and hydrology related impacts. The Division and Snowcap Coal Company will need to address the longer term issues associated with the apparent subsidence impacts to the Fontanari and Carey properties, and the potential impacts to land use(s) for the ground above the Roadside South Portals Mine. An Order relative to this is attached to this Findings as Attachment 16. Because of these uncertainties, specific disturbed area acreages and affected area acreages will be disallowed for final bond release. Affected areas and all surface disturbed areas that overlie underground workings that are either hydraulically down gradient or have the potential to be in hydrologic communication from the location on the Fontanari property where water was applied to the surface down to the Outfall 016 discharge will be withheld from final bond release. The disturbed areas (8.0 acres) and affected areas (114.1 acres) being withheld from final bond release pending further investigation is shown on Attachment 5. An additional 0.5 acres is disallowed for Phase III bond release for weed/vegetation concerns as previously described in this Findings document. TOPSOIL Topsoil was salvaged and replaced on all disturbed areas of the mine site excluding Pre -Law Areas. Pre -law refers to those lands that are mined prior to the passage of the Surface Coal Mining Reclamation Act on August 1, 1979. The reclamation criteria considered during this bond release inspection for those areas evaluated as Pre -Law included backfill and grading, site stability, drainage control, and erosion features. For the purposes of this bond release, this applies only to the Roadside South Refuse Disposal Area (RSRDA) and Substation B. No topsoil had been salvaged at these two Page 33