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-46- No information has been provided to indicate the presence or absence of subirrigation in Santistevan Canyon. The information on alluvial ground water included in the application is limited to the Picketwire Valley (Exhibit 6). However, the presence of springs in Santistevan Canyon is shown on the USGS topographic map of the area. Because of a lack of site specific information and the presence of springs, the Division must assume that subirrigation does occur in Santistevan Canyon, unless the permittee demonstrates the absence of subirrigation in the canyon. Based on the information provided, Santistevan Canyon is found to be an alluvial valley floor based upon the capability for subirrigation. Apache Canyon and Santistevan Canyon Findings 1. With the acceptance of Stipulation No. 12, the Division can find that the proposed operation would not interrupt, discontinue or preclude farming on the Apache Canyon or Santistevan Canyon alluvial valley floors. The applicant has proposed no surface disturbance in Apache Canyon and Santistevan Canyon. However, portions of the canyons are planned to be undermined. The applicant has not projected the effects of full extraction mining under Apache and Santistevan Canyons. Development mining should result in no subsidence effects and, based on monitoring of inflows into mine workings below Apache Canyon at the Allen and Maxwell Mines, development mining will not significantly affect the alluvia] aquifers of Apache and Santistevan Canyons. 2. With the acceptance of Stipulation No. 12, the Division can find that the proposed operation would not cause material damage to the quantity and quality of ground water that supplies the Apache Canyon and Santistevan Canyon alluvial valley floors. The applicant has proposed no surface disturbance in Apache Canyon and Santistevan Canyon. Therefore, the proposed operation will not affect the quality of water that supplies the alluvial valley floors. However, portions of both canyons are planned to be undermined. The applicant has not projected the effects of full extraction mining upon the alluvial valley floors. As previously discussed, development mining will not result in significant depletion of the alluvial aquifers of Apache and Santistevan Canyons. 3. With the acceptance of Stipulation No. 12, the Division can find that the proposed mining operation would preserve the essential hydrologic functions of the Apache Canyon and Santistevan Canyon alluvial valley floors. The Division has conservatively assumed that Apache Canyon and Santistevan Canyon are subirrigated alluvial floors significant to agriculture. Therefore, the essential hydrologic function must be preserved throughout the mining operation. The essential hydrologic functions are those geologic, hydrologic, and topographic characteristics which make the ground water usefully available for subirrigated agriculture.