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(970)824-4943 regarding the as-built configuration of the pond. Mr. Frey concurs that the pond does not fall within the jurisdiction of MSHA because 1) the inside toe of the embankment portion of the pond is less than 20 feet high; 2) the pond is only 6 ac-ft in size rather than the 20 ac-ft for jurisdictional ponds and 3) the pond is located such that it does not pose a threat [o the health and safety of the miners. Mr. Frey indicated he would be pleased to discuss the matter further with you if you so desire. We have also included for the Division's information a copy of an MSHA "Program Policy Manual" that states that jurisdictional structures do not include incised ponds, constructed on undisturbed flat ground unless such ponds present a hazard [o coal miners. Such is the case with the East Taylor pond. We hope this information is helpful. CDMG Comment # 2 Colowyo has utilized the SedCad modeling program to design the East Taylor pond such that among meeting other requirements, it will be in compliance with Rule 4.05.6(3)(a) by containine the runoff or inflow entering the pond as a result of a theoretical 10-year, 24-hour precipitation event rather than treatine the runoff: We believe the Division's concern fora "permanent pool" is primarily applicable to those ponds designed to "treat" runoff, such as those ponds having combined open spillways or perforated inverts without a manual dewatering device. In these examples it is quite possible that a permanent pool could exist for an extended period of time. The presence of a permanent pool was never intended to be a component of the design nor the anticipated operation of the East Taylor pond. The design, construction and operation of the East Taylor pond is similaz to that found for all of the other eight sedimentation ponds used at Colowyo, all of which have been successfully operated for up to fifteen years. In general, the ponds are designed and operated such that the water level is maintained at minimum levels providing for sufficient capacity to store the inflow from a theoretical design runoff event. Runoff water is then held temporarily in the pond until such time that it meets applicable dischazge standazds then released through the manual headgate. When compared to automatic pond dischazge systems, this manual headgate system provides a faz superior level of control over the quality of water discharged from the pond. Under normal circumstances, we can control the water quality leaving the pond, unlike an automatic discharge system which cannot be controlled, even if noncompliance situations are encountered. Attached for the Division's information are the as-built volumetric calculations for the East Taylor pond, showing that the sediment and water capacity exceed the required capacity. For example, where, the theoretical modeling indicated that the pond should have the capacity to hold 5.66 ac-ft of runoff volume, it is capable of containing 5.99 ac-ft of water volume before discharging. Since mining (and ultimately, future reclamation) has now started in the watershed