2012-12-26_HYDROLOGY - M2003091 - Laserfiche WebLink

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David Heintz or Kristina Wynne 4 -0 — Bishop - Brogden Associates 333 West Hampden Ave., Ste 1050 Englewood, CO 80110 DEPARTMENT OF NATURAL RESOURCES DIVISION OF WATER RESOURCES December 24, 2012 Re: Duckworth Substitute Water Supply Plan (WDID 0602525) Duckworth Pit, DRMS Permit No. M.003 -091 (WDID 0603005) Section 35, T1S, R67W, 6 t'' P.M. Mt i.003-091 Division 1, Water District 2, Adams County r s John W. Hickenlooper Governor Mike King Executive Director Dick Wolfe, P.E. Director /State Engineer RECEIVED DEC 2v� 2 12 Division of Reclamation, Mining & Safety Approval Period: November 1, 2012 through October 31, 2013 Contact phone number for Mr. Heintz or Ms. Wynne: 303 - 806 -8952 Dear Mr. Heintz & Ms. Wynne: We have reviewed your letter dated September 10, 2012 requesting a substitute water supply plan ( "SWSP ") in accordance with § 37 -90- 137(11), C.R.S., to cover depletions caused by mining operations at the Duckworth Pit operated by Martin Marietta Materials ( "MMM" or "Applicant ") along Boulder Creek. The original plan was approved on July 20, 2005 and it was most recently approved in a letter dated April 2, 2009. Mining never commenced under those plans and the SWSP was allowed to expire. This is a new plan and the required fee of $1,593 for the SWSP has been submitted (receipt numbers 3656976 & 3657454). Plan Operation This SWSP covers depletions caused by sand and gravel mining operations at the Duckworth Pit. Mining operations are projected to occur in two phases over four or five years beginning in November 2012. This plan period will see approximately 14 acres mined in the southeastern corner of the property. Dewatering will occur to allow for dry mining at the site. Operations that will consume water include exposing ground water, dewatering, mining and removal of product, and dust control. Replacement water will come from dewatering credits, Rural Ditch shares, and excess accretions from MMM's South Platte Combined SWSP (WDID 0202581). Depletions Evaporation and Mining Operations Net evaporative depletions are calculated using a gross annual evaporation of 40 inches per year per NOAA Technical Report NWS -33. This is reduced by applying a credit of 9.1 inches for effective precipitation which is 70% of the average annual precipitation based on Longmont 2, CO (ID #5116) NOAA weather station. Based on an exposed acreage of 0.45 acres, the total net evaporative depletion is 1.15 acre -feet per year as shown on Table 1. The Applicant has estimated that 7.94 acre -feet of water will be used for dust suppression at the site and will occur during the months of aggregate production. Mining is expected to occur in the months of March, April, June, and September of 2013 with a total amount mined of 365,000 tons. The aggregate will be crus not washed and mined in a Office of the State Engine v SC 1313 Sherman Street, Suite 818 • Denver, CO 80203 • Phone: 303 -866 -3581 • Fax: 303 - 866 -3589 www.water.state.co.us