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Cemex Vernalis Quarry Mining and Reclamation Project 3.6.3 Processing Facility Water It is estimated that overall project operations would require approximately 3,840,000 gallons of water per day (approximately 3,040 acre feet annually)at 1.7 mty. The volume of water required for dust suppression would be approximately 80,000 gpd during dry months; landscaping would _ require approximately 8 acre feet per year for approximately 17 acres of land;and water demand for the Ready Mix Plant would be approximately 25,000 gpd. The Applicant would use well water and recycled water from silt ponds for water supply.Well water would be used exclusively until silt ponds are established. Once the silt ponds are established,the Applicant would recycle the decanted waters from the silt pond for use in — washing the sand and gravel; however it is anticipated that approximately 25 percent of the project's water requirement would be supplied from the well water. A temporary silt pond would be built in the Phase IVR VII area by stripping the overburden from the Phase I area and creating a basin.The applicant would use well water at the rate of approximately 3.8 mgd to 8.9 mgd(based on a production range of 1.7 mty to 4.0 mty) until there — is enough wastewater to be recycled in the temporary silt pond. Once water recycling begins,the applicant would only need to replenish the amount of water lost to evaporation and/or sold in the product. Once the silt pond is established,it is anticipated that only 0.28 mgd to 0.4 mgd of water supply would be supplied by well water. The volume of water needed for replenishment is provided below. — • Evaporation loss: The temporary silt pond in the Phase WB VII area would measure 40 acres. Therefore,evaporation for the year(at 6 feet per year)would be 78.2 million gallons annually (240 acre-feet),or 214,200 gallons daily. — • Production loss: Assuming seven percent loss in the product(i.e.,products will have an average of 7 percent moisture when they leave the project site)at a production rate — of 1.7 million tons per year,product loss would be approximately 210 million pounds of water annually,or 68,500 gallons of water daily. • Total loss: By adding the evaporation and product losses the total water loss would be 282,700 gpd with a production rate of 1.7 million tons per year.With a production rate of 4.0 million tons per year,the total loss would be 396,800 gallons of water daily. — 3.6.4 Reclamation The Applicant and its consultants have prepared a reclamation plan for the RMC Pacific (Now Cemex)Vernalis Quarry, dated OntebeF November 2003, pursuant to the requirements of the _ Surface Mining and Reclamation Act(SMARA)and the County's mining ordinance. Cemex Vernal¢Quarry Mining and Reclamation Project 4-12 ESA 12 15 Final Emironnental Impact Report June 20ne