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and ditches; and by whom the study was conducted. Additional information is needed to substantiate that subirrigation is not present along both Scullion Gulch and Red Wash, especially since subirri- gated vegetation species have been identified in these areas. Areas of subirrigation within the AVF study area should be identified on the Alluvial Valley Floor Map. If any of these areas are greater than 10 acres in size, the applicant should submit arty additional information concerning subirrigation available (e.g., data from backhoe pits within the alluvium to check for groundwater and soil mottling, geophysical measurements of soil moisture, and the use of infrared photos). If no specific information is available, additional studies may be required. The potential for flood irrigation of areas of Scullion Gulch and Red Wash also needs to be assessed. Red Wash, especially, has a large enough drain- age area to make limited irrigation a distinct possibility. (4) Application Contents for Operations Affecting Alluvial Valley Floors This Section, Section 2.06.8(5), and Section 4.24 of the Colorado permanent regulatory program delineate the information which must be submitted for those areas which are identified as Alluvial Valley Floors. The applicant should carefully review these sections of the regulations and submit the appropriate information as part of the permit application. Specifically for the White River AVF, pump -tests should be run on the alluvial wells to determine the aquifer characteristics of the alluvium. Based on the aquifer characteristics, the applicant should then estimate the impact that worst -case pumping conditions could have on the AVF, e.g., the extent of draw - down, the effect on subirrigation both adjacent to the wells and downstream/ down gradient of the wells, and the reduction in flow in the White River and its alluvium as a result of pumping. -22-