2015-02-05_PERMIT FILE - M2015003

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G -3. PROJECT WATER REQUIREMENTS: Water use for extracting and processing aggregates from the pit will be low, amounting to less than 6 acre -feet per year under worst case conditions. This water will come from the temporary industrial use of agricultural water from existing water rights for the property, from the San Juan River. Based on data available on historic irrigation of the property, of irrigated land, it may be necessary for the landowner to dry up approximately 3 acres of land in order to provide augmentation, if such is necessary, and the landowner is willing to do so. However, to the best of our knowledge, the San Juan River is not overappropriated and no augmentation or substitution is required. The primary use of water on the site is for dust control and other pollution control, with secondary use for washing (if washing is done on site) and compaction of backfill. Use of dust control chemicals will reduce water use on site. If materials are washed, water will be recycled, reducing use and discharge, as well as protect water quality. For evaluation purposes, based on the assumptions listed below Table G4, the estimated operating losses of water for the Constant Pit are shown in this table.7 i aDie Lj-4. iviaximum rro ect vvater Ke uirements Lfiyh Acre -Feet Period Flow Remarks ep r year (gal/day) Dust control of roads 2.0 0.1 in /day, 120 days 5,430 2.0 acres max Dust control of plant sites 1.0 0.1 in /day, 30 days 11,132 4.1 acres max Dust control of pit area 1.0 0.1 in /day, 60 days 5,702 2.1 acres max Water removed with materials mined 0.03 Variable 11,191 4% of weight of product Washing of materials 1.2 30 days 6,667 Evaporative loss Total water required 5. 2T acre -feet 40,122 Worst -case Water available 9.00 As needed Not including direct precipitation This is based on the following assumptions: • 70,000 tons per year produced. • Maximum (all roads in operation): total affected area for roads is 2.0 acres. • Plant areas include long -term stockpiles, storm water structures, and other areas with no traffic and no need for dust control. Total plant areas are 4.1 acres, but only 1/2 (2 acres) will require regular dust control. Plant sites are also seasonal: the asphalt plant would usually only operate approximately 8 months per year, the concrete plant approximately 9 months per year. • Maximum pit area with exposed surface including temporary topsoil stockpiles is 2.1 acres for any given year, which are assumed to be completely open and require application of water for the entire period of their use, but actual mining and processing (crushing /screening) is expected to take approximately 60 days per year. • No precipitation during any operations on site. (In actuality, as many as 30 days per year we can expect at least 0.1 in /day and so require no watering.) (Annual precipitation in the area is 17 inches per year.) • No dust control chemicals be used. (In actuality, air permit requirements will have to be met and magnesium chloride brine, sodium lignite, or other dust control chemicals will be applied to areas with high traffic. • No water from any source other than the San Juan River to be used for dust control. • No open water except wash pits (included in wash water use). As no ground water is exposed (by mining below the water table) and no water is retained in surface impoundments (actually incised basins), no requirement for a substitute water supply plan to be prepared and submitted to the State Engineer, pursuant to SB 89 -120 and SB 93 -260 has been identified. A temporary water use agreement will probably be necessary to allow landowners' irrigation water to be used on a temporary basis each year for the above purposes, with such water to be provided together with irrigation water delivered for the normal irrigation season. Any water needed would be taken from the River DOWNSTREAM from the neighbor's irrigation ditch intake to prevent disturbance of that water system. 7 Based on assumptions as discussed in Exhibit M. C &J Gravel Products, Inc. Page 33 01 JAN 2015 Application for Permit: Two Rivers Pit M -2015- C &J- TRP -V5 -001