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• Rcsponsc-The applicant will !i~~rit *.he dewatering pit to 1-acre in size for dredge construction. Once the dredge is constructed, [he pumps wil I be shut off and the area will be we[ mined. In addition, the applicant will begin mining as tar away from the existing wells as possible. The report prepared by Leonard Rice Consulting Water Engineers, Inc. demonstrates that limiting [he dewatering activity [o a maximum area of 1-acre, will not impact adjacent well owners and infringe on their water rights. Any change in this plan (includingdry mining greater[han 1-acre in size) will need to be submitted as a revision to [he permit. At that time, [he Division will review the impacts to the hydrologic balance and surrounding well owners. 9. "Proper containment and disposal of mine and plant generated chemicals or other toxic by-products are essential to groundwater protection. These containment and disposal plans must be detailed prior to granting permit." (Scott, Brochard, Depratt, Odenbaugh, Remick & Rippe; February 11, 2001) Response-The applicant is required to properly dispose of mine and plant generated chemicals in accordance with the Regulations of the Colorado Department of Public Health and Environment. Only `'inert material" may be left on site and utilized in the reclamation plan. The plant area will facilitate portable structures including a process plant, asphalt batch plant and concrete plant. Water associated with the processing plant area will be directed to [he silt pond and contained on the mining area. The concrete and asphalt plant will be lined with a double layer of 60- mil vapor barrier and will be used as a double liner in the depression. Four inches of clean sand will cover the barrier and will be capped with roadbase material. In addition, a smal I containment berm will be placed around the plant site to contain the area. The berm will be engineered to contain the amount of liquid products stored in each plant site area. 10. "The proposed site is entirely within the 100-year flood plain for the South Platte. The applicant should provide a detailed plan of operation which will protect adjacent and downstream residents from mine or plant produced effluent in the event of periodic flooding of the adjacent South Platte River." (Sco!!, Brochard, Depratl, Odenbazrgh, Remick & Rippe; February Id, 2001) Response- The applicantwill not mine in the floodplain until a floodplain analysis and mitigation plan is developed and submitted to the Division for review and approval. I I. "The application should provide a site specific review and identification ofjurisdictional wetlands prior to granting the permit. This study should be undertaken by a neutral third party agency" (Scott, Brochard, Depratt, Odenbaugh, Remick & Rippe; Febnrary 1 ~, 2001) Response- A preliminary wetlands study was completed by ERO Resources in 2000, and a copy of the wetlands identification map was subm fitted [o the Division. Platte Sand & Gravel states [hat they wil I not impact [he wetland areas at this time. A letter dated April 1, 2001 from the Department of the Army Corps of Engineers states that the area to be mined in the next I S years is not a wetland. if and when a U.S. Army Corps of Engineers 404 Permit is issued, it must be submitted to the Division to determine what course of action will be needed regarding the reclamation plan and the reclamation cost estimate. 12. "The water which would be required For augmentation of the evaporative loss from the lake surface in this reclamation plan is significant. The water is currently available for agriculture production and i[ would be lost for such purpose in perpetuity." (Scott, Brochard, Depratt, Odenbaugh. Remick & Rippe; February Id, 2001) Response- Platte Sand & Gravel predicts that 2,274.23 acre-feet of water to evaporate from the exposed lake areas each year. This assumes a lake surface of 768.32 acres with an average net annual evaporation of 2.96 acre- ft/surfaceacre. The applicant states they have no current water rights to use for makeup water. The applicant may not expose groundwater until a well permit is issued by the Colorado Division of Water Resources, Office of the State Engineer ("OSE"). The applicant states that a Temporary Substitute Supply Plan ("TSSP") and well permit have been filed with the OSE. In the TSSP, the applicantwill commit to buying water from Longmontto cover the industrial and evaporative uses associated with [he operation during the first five years. The applicant has committed that groundwater will not be exposed until they have received necessary approvals from the OSE. 5