Laserfiche WebLink
~~4nr <br />March 30, 2007 <br />Mr. Aiex Schatz <br />Banks & Gesso <br />720 Kipling St., Suite 117 <br />Lakewood, CO 80215 <br />Dear Alex: <br />Martin and Wood Water Consultants, lnc. <br />602 Park Point Ddve, Suite 275, Golden, CO 80901 <br />Phone: (303) 526-2600 . Faz: (303) 526-2624 <br />www.martinandwood.mm <br />Re: Lafarge Sundance Gravel Pit <br />Dewatering Effects <br />Project Number: 536.4 <br />This letter report presents the results of a ground water modeling study conducted on <br />behalf of Lafarge for their proposed sand and gravel pits located within portions of Sections 9, <br />10, 14, 15, 22, and 23, Township 17 South, Range 65 West in EI Paso County, Colorado. This <br />study was conducted to determine the effects of dewatering of the gravel pits on the surrounding <br />area and nearby wells. <br />Background <br />Lafarge is planning to mine a gravel pit over approximately 15 years on property south of <br />the Fountain adjacent to Fountain Creek. A map of the proposed gavel pit locations is presented <br />as Figure 1. Lafarge is proposing to mine the site in phases. Each small mine cell will be <br />dewatered, and Lafarge will remove the gravel with dry mining techniques in Phases 1 and 2. <br />Two large areas (Cells 5 and 6) will be mined after constructing slurcy walls around the proposed <br />cells. Generally, the smaller cells with be mined from north to south. After each pit is mined, it <br />will either be completed and converted to a reservoir or filled in with native material as <br />subsequent cells are mined. The cells shown are for modeling purposes and may change when <br />mining occurs. <br />As is required for a gravel pit-mining permit from the DRMS, the effects of dewatering <br />wells within 600 feet must be determined. Banks and Gesso, LLC, has provided us with a map <br />locating these wells (Banks and Gesso Exhibit C-1). These wells, identified by their Exhibit C-1 <br />well number, are also presented in Figure 1 of this report. <br />Geology <br />The proposed gravel pit is located within the Fountain Creek alluvium. Martin and Wood <br />utilized United States Geological Survey Water-Supply Paper 1583 (Jenkins, 1964), geologic <br />(lithologic) boring logs provided by Lafarge, and Colorado State Engineer records of wells in the <br />vicinity to interpolate the geology of the alluvium near the mining area. <br />