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<br />At this time, all structures will remain at the site in anticipation of <br />improved market conditions. The operation is in compliance with the <br />requirements of this section. <br />B. Roads <br />Based on information presented in Section 2.05.3 (Volume I) of the <br />application, it has been determined that the roads are designed in compliance <br />with Rule 2.05.3(3) and performance standards in Rule 4.03. The operation is <br />in compliance with the requirements of this section. <br />C. Impoundments <br />Two major areas of concern were raised during the sediment control review. <br />These were: 1) Sediment yields that were questionably calculated using the <br />Universal Soii Loss Equation, and 2) Inadequate culvert sizing. <br />Because the assumptions used were not conservative for calculating runoff <br />volumes and sediment yield for the capacity of pond H-G-B, it was at first <br />believed that the pond may be undersized. In light of further information <br />supplied by the applicant and additional analyses by the Division staff it has <br />been determined that the pond design is in compliance with the Rules and <br />Regulations. Pond H-G-8 was originally designed to contain three years of <br />sediment accumulation in addition to the runoff from the 10-year 24-hour <br />storm. Using more conservative parameters for crop cover and sediment density <br />and giving consideration to the surface manipulation which is employed by the <br />operator, it is evident that the design allows for the storage of at least one <br />years sediment accumulation plus the runoff from the 10-year 24-hour storm. <br />This satisfies the requirements of Rule 4.05.6(3)(b). <br />To determine any need for sediment removal H-G Coal Company has agreed to <br />monitor the level of sediment in all ponds. Sediment levels in the ponds will <br />be surveyed during mid to late summer every year and a report will be prepared <br />and certified by a registered professional engineer. If the sediment level is <br />at 60% of maximum volume it will be cleaned. <br />The remaining ponds for the shop area, sanitary facilities, explosive storage <br />and tipple areas do not have devices for dewatering to the maximum sediment <br />storage level. Topographic restrictions prevent the placement of a functional <br />dewatering device in all ponds but the one at the shop area. Principal and <br />emergency spillways are appropriately sized and all ponds are designed to <br />contain a maximum sediment volume in addition to the volume of runoff from the <br />10-year 24-hour storm event. <br />H-G Coal Company has agreed to pump any water stored in the ponds at the <br />sanitary landfill and explosive storage area within 24 to 36 hours of a storm <br />event. Additionally, information has been supplied showing that water levels <br />in ponds at the shop area and tipple can be maintained to allow further <br />storage of the 10-year 24-hour event. This information is located in Appendix <br />E (Volume III) of the application. <br />-31- <br />~ _. <br />