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• All existing ponds in both the Southfield mine and loadout areas were <br />constructed by Dorchester prior to EFCI's purchase of the properties in <br />early 1985. Ponds were constructed using conventional earth moving <br />practices and were functioning as designed at the time of purchase with <br />no evidence of any stability or significant erosion problems. EFCI has <br />completed minor modifications to the ponds to ensure continuing compliance <br />with applicable regulations. In addition, the ponds have been inspected <br />on a quarterly basis to identify any evidence of structural weakness or <br />significant erosion and to verify that all associate spillway and <br />discharge structures are functioning properly. <br />Based upon current plans for development and production from the <br />Southfield Mine, EFCI does not anticipate the need to construct any <br />additional sedimentation ponds. Existing ponds have been designed to be <br />stable under all conditions of construction and use and to minimize <br />maintenance requirements. EFCI will continue regular quarterly pond <br />• inspections and as appropriate will correct any situation which may impact <br />structural or hydraulic integrity of pond embankments. This will include <br />repair of any significant erosion, removal of any excess vegetation which <br />may hinder inspection or interfere with operation of discharge structures, <br />clean-out of discharge structures as required, and removal of excessive <br />accumulations of sediment as necessary. These measures will ensure that <br />ponds continue to function as designed and maintain required storm <br />retention capacity. <br />Existing sedimentation ponds are operated in compliance with NPDES <br />discharge standards. EFCI holds NPDES discharge permits CO-0036595 (Mine) <br />and CO-0037109 (Loadout). Under NPDES discharge permits, EFCI regularly <br />monitors any pond discharge to ensure compliance with effluent <br />limitations. Sedimentation ponds have been designed to capture and retain <br />runoff from contributing disturbed and non-disturbed drainage areas. With <br />a design minimum detention time of 24 hours, any suspended solids in the <br />runoff are allowed to settle out in sedimentation ponds prior to discharge <br />• of water to natural drainages. In the four (4) years that EFCI has <br />operated the Southfield Mine there has been no significant degradation of <br />2.05.3-48 <br />