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of the model calibration process. The State Engineer finds that Mr. Bedard and James <br /> Thomson, P. G., provided persuasive explanations for adjusting the recharge value as part <br /> of the calibration process. The State Engineer, therefore, finds the final recharge value <br /> used in the model to be reasonable. Certain parties also objected to the manner in which <br /> the NSJB Model was calibrated to springs. The State Engineer finds,based upon the <br /> testimony of Mr. Bedard and Mr. Thomson, that the model was appropriately calibrated <br /> to springs. <br /> Fourth, the State Engineer finds that there is clear and convincing evidence that the NSJB <br /> Model was appropriately adjusted based upon corrections to the storativity values for <br /> cells located at the outcrop. The State Engineer finds that these corrections were <br /> necessary to correctly model unconfined conditions at the outcrop. <br /> Fifth, the State Engineer finds the peer review of the NSJB Model, in the form of the <br /> participation of experienced engineers and hydrogeologists in a Technical Advisory <br /> Group, to be additional clear and convincing evidence that the NSJB Model is capable of <br /> accurately delineating areas within the Fruitland Formation in the NSJB. In particular, <br /> the State Engineer finds convincing the testimony of Phillippe Martin, P.G., C.P.G., a <br /> hydrogeologist with many years of experience working directly with ground water <br /> models, Colorado water issues and Colorado water law. The State Engineer finds the <br /> participation of these individuals is additional evidence that the NSJB Model was <br /> developed in a conservative manner using accepted and supported values and <br /> methodologies. Participation by these individuals also addressed any concerns raised <br /> regarding the experience of Mr. Bedard with respect to Colorado water law issues as it <br /> may relate to developing the conceptual and numerical models. <br /> In summary, the State Engineer finds the NSJB Model to be well-conceived and <br /> consistent with the known geologic/hydrogeologic framework of the Northern San Juan <br /> Basin. The inputs to the NSJB Model are based upon particularly complete and robust <br /> data. All data were within the expected range. The NSJB Model was thoroughly <br /> calibrated and had undergone appropriate peer review. No aspects of the conceptual and <br /> numerical models are indicative of errors that would cause significant error in the <br /> proposed line derived from the NSJB Model demarcating the division between tributary <br /> and nontributary ground water. The State Engineer thus finds there to be clear and <br /> convincing evidence supporting his adoption of a rule identifying water withdrawn from <br /> the Fruitland Formation by wells located within areas delineated through use of the NSJB <br /> Model to be nontributary for purposes of his administration and permitting of wells <br /> pursuant to C.R.S. § 37-90-137(7). <br /> Rules for Piceance Basin—Neslen Formation. The State Engineer finds there is clear <br /> and convincing evidence supporting his adoption of a rule identifying water <br /> withdrawn from the Neslen Formation within a delineated area of the geologic <br /> formation known as the Piceance Basin in Garfield and Rio Blanco Counties, <br /> Colorado to be nontributary for purposes of his administration and permitting of wells <br /> 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 /> -15- <br />