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Witt were on the lower end of the range of values for coal deposits as commonly <br /> presented in the literature. However, the values were within the acceptable range. In <br /> addition, the values provided were supported by research of coal fractures and <br /> permeability in nearby coal mines conducted by other investigators. The State Engineer <br /> finds this independent, site-specific data to be convincing evidence that values used were <br /> correct and that these values are further supported by supplemental evidence provided by <br /> Mr. Witt regarding the dry condition of adjacent coal mines. <br /> Certain parties commented with respect to whether Mr. Witt considered all appropriate <br /> potential points of depletion. Specifically, these parties questioned whether Mr. Witt <br /> should have included depletions to ephemeral streams located within the study area as a <br /> point of depletion to a"natural stream" for purposes of the definition of nontributary <br /> water at C.R.S. § 37-90-103(10.5). The State Engineer believes it is unclear at this time <br /> whether and when modeling to an intermittent or ephemeral stream is appropriate. As <br /> noted by Mr. McElhaney, for bedrock aquifer applications, it has been the general <br /> practice of the State Engineer's Office to model depletions to the nearest perennial stream <br /> and its saturated alluvium,rather than to intermittent or ephemeral streams, in order to <br /> avoid classifying as natural streams channels where stream flow is often only associated <br /> with extreme or prolonged precipitation events and the alluvial saturation is unknown, or <br /> where the condition of the channel or alluvium otherwise does not justify modeling <br /> depletions to that location. However, the State Engineer has in certain circumstances <br /> modeled stream depletions to ephemeral or intermittent streams with saturated alluvium. <br /> In this case, the State Engineer does not need to reach a decision on this issue with <br /> respect to the rule for the Piceance Basin—Mesaverde formation,because the evidence <br /> was clear, and all parties agreed, that in this instance modeling to any additional <br /> intermittent or ephemeral streams would not have altered the location of the line <br /> demarcating the tributary and nontributary areas. <br /> In summary, the inputs to the analysis are appropriate and based upon site specific data. <br /> All inputs to the data are within the expected range. No aspects of the analysis are <br /> indicative of errors that would cause meaningful error in the proposed line derived from <br /> the model demarking the division between tributary and nontributary ground water. The <br /> State Engineer finds the Glover analysis performed by Mr. Witt to provide clear and <br /> convincing evidence in support of the State Engineer's adoption of a rule identifying <br /> water withdrawn from the Cameo and South Canyon Coal Groups of the Mesaverde <br /> Formation by wells located within a delineated area of the Piceance Basin in Delta and <br /> Gunnison Counties, Colorado to be nontributary for purposes of his administration and <br /> permitting of wells pursuant to C.R.S. § 37-90-137(7). <br /> Produced Nontributary Ground Water Rules 2 CCR 402-17, Statement of Basis and Purpose <br /> -12- <br />