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(i) Groundwater encountered and/or surface water intercepted. As stated in Site Description (c): The proposed area of operations lies to the East of the San Juan River on an elevated terrace approximately 10 to 14 feet above the current surface of the river. Onsite test pits excavated to the basement Mancos Shale to average depths of 12 feet intercepted some minimal groundwater seepage on the top of the shale emanating from the hillside slope to the west. Lateral groundwater seepage was also observed in pits located close to the river. These test pits were excavated in 1999-2000. Current water levels are lower due to extended drought conditions and seepage is expected to be much less than previously observed. A settlement pond/sump is planned to be installed in the south end of the pit excavation in order to control and contain intercepted groundwater or seepage that may be encountered during mining activities. These waters will be allowed to settle prior to controlled release back into [he river. The entire approximate 5 acres of planned pit area will be reclaimed as a developed water resource area (pond) with an inlet and outlet ditch and headgate structures similar to ones currently in use at other pond locations on the Mask Ranch. The location oY these existing ponds and the proposed pond may be found on the Exhibit A -Map 5. Silt fences and sediment retention berms or ditches will be maintained alongside roads and excavation areas to reduce erosion and limit runoff from storm events. (j) Compliance with applicable Colorado water laws and regulations governing injury to any existing water rights. See (i) above and Site Description (c ). (k) Refuse and acid-forming or toxic materials exposed handling and disposal. No refuse and acid forming or toxic materials will be involved in this operation. The mining operation will be completed and the site fully reclaimed as quickly as possible. Sand and gravel will be produced with no chemicals required for processing and refuse will not be generated. Sand and gmvel are basically inert materials. (1) Measures to minimize disturbance to the hydrological balance, prevent offsite drainage, and provide for a stable configuration of the reclaimed area consistent with the proposed future land use. The hydrologic balance issue has been addressed previously in Site Description (c), and items (i) and (j) above. Astable configuration will be accomplished by the 3:1 backsloping of the pit faces on all sides of the pit area. The ultimate shoreline of the pond will be slightly irregular and a small island will be installed as recommended by the Archuleta County Soil Conservation District/USDA Pagosa Springs Field Office. (m) Specify whether the deposit will be processed on-site. As stated in (e) 4 above: A portable crusher/screening plant will be mobilized ro process material at this site. The entire planned mine pit area will be excavated processed and stockpiled during a single crusher mobilization to the site. All material will be handled onsite using bulldozers and front-end loaders to temporarily stockpile and load to haul trucks. Material stockpiles for commercially available material will be located on the northwest side of the mine pit/reclaimed pond area. Approximately 40% of the processed material will be reserved for road construction activities on the Mask Ranch. This material will be stockpiled outside the proposed permit azea. No structures are proposed onsite.