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HBET reviewed the second Fugro report and came to the following conclusion: <br /> As indicated in the attached report, the geophysical survey identified a <br /> linear, horizontal anomaly that extends from the surface sinkhole <br /> openings in the trench to the vertical anomaly previously identified. Based <br /> upon all of the available data, HBET believes that the horizontal anomaly <br /> represents the pathway from the sinkhole openings to the old air shaft. <br /> The recent survey also identifies a horizontal anomaly north of the air <br /> shaft. However, the anomaly does not appear to connect to the air shaft. <br /> In addition, no surface sinkhole expression was observed in this area. <br /> Although the survey identified two horizontal anomalies, the data did not <br /> identify any horizontal anomaly extending from the rock pile feature <br /> discussed in the report.As indicated in the referenced Fugro report, water <br /> was dumped into this feature and as a result, HBET would have <br /> anticipated that any horizontal anomaly extending from this location <br /> would be identified during the survey. (See HBET report dated August 25, <br /> 2016 located in Appendix 14-15) <br /> The air shaft was constructed in the 1979 time frame to ventilate a mining area known <br /> as the northwest section, also know as C-section. According to the old mine maps, C- <br /> section was mined out in September 1979. It appears the shaft was constructed post <br /> law(after August 3, 1977) but prior to the 1981 permit issuance. <br /> The Operator does not have any detail on how the shaft was constructed or how the <br /> shaft was sealed. It is likely the shaft was sealed by dumping soil and rock into the shaft <br /> until it was filled to the surface. A void in the shaft could have been created by settling <br /> of the backfill. <br /> The Fugro reports show the extent of the hydrologic communication are the old air shaft <br /> and the near surface anomalies extending between the trench and the old shaft. The <br /> following repair plan will stop the hydrologic communication between the underground <br /> workings of the Roadside Mine and the properties overlying these workings that belong <br /> to Mr. Rudolph Fontanari and Mr.Jason Carey <br /> Air Shaft Repair and Pathway to the Air Shaft <br /> The Operator proposes to use a large backhoe to excavate the area from the Fontanari <br /> trench to the shaft as shown on Figure 14-17. The excavation should uncover the near <br /> surface anomalies that run from the trench to the shaft. The shaft will be excavated 16 <br /> feet deep. A 12-inch thick low slump concrete slab will be placed to seal off the shaft <br /> at this elevation.The native soils excavated from the area should be void of rocks larger <br /> than 6 inches and placed in compacted lifts back up to original grade. <br /> TR-69 14-34 12/16 <br />