2003-11-10_REVISION - M1978056 - Laserfiche WebLink

Home Browse Search

STATE OF COLORADO OFFICE OF THE STATE ENGINEER Division of Water Resources Department of Natural Resources 1313 Sherman Street, Room 818 Denver, Colorado 80203 Phone (303) 866-3581 FAX (303) 866-3589 www.waterstate.co.us July 10, 2003 Ms. Cheryl Signs Cheryl Signs Engineering 109 East Fourth Avenue Denver, CO 80203 Re: Substitute Water Supply Plan, Durham Pit (DMG #M-78-056) Sections 3, 9 and 10, T5N, R65W, 6th P.M. Water Division 1, Water District 3, Weld County Dear Ms. Signs: n"-.-4 Bin owens Greg E. wakher Executive Director Hal D. Simpson, P.E. State Engineer This letter is in response to your application for a substitute water supply plan for the Durham Pit. The required fee of $1,343 for the substitute water supply plan has been submitted. The anticipated net depletion for this plan, based on the numbers provided in the substitute water supply plan report, is 194.9 acre-feet per year. The currently exposed ground water at the site totals 38.1 acres. However, the plan anticipates that a total of 79.2 acres of water surface will be exposed at the site if dewatering ceases, therefore this plan will cover replacements for depletions associated with the 79.2 acres. According to the information submitted, 44.6 acres of water surface, out of a total of 123.8 acres to be exposed at the site, was exposed within the reclamation permit boundary prior to January 1, 1981. You have provided a monthly breakdown of the annual depletions made up of 184.30 acre-feet of net evaporative loss, 7.8 acre-feet of water lost with the mined product (which represents 267,931 tons of mined product), and 2.8 acre-feet of water used for dust control. Using to the State Engineer's General Guidelines for Substitute Supply Plans for Sand and Gravel Pits, the State Engineer has determined the net depletion for this plan to be 222.99 acre-feet for the 79.2 acres of water surface to be exposed at the site: Based on the above- mentioned guidelines the net. evaporation for the 79.2 acres was calculated as the difference between gross evaporation and the effective precipitation, where the effective precipitation is equal to 70% of the total precipitation. Therefore, for this plan no benefit was given for the total precipitation but only for 70% of the total precipitation, which increased the annual evaporative loss from 184.30 acre-feet to 212.39 acre-feet. A monthly breakdown of the annual depletions made up of 212.39 acre-feet of net evaporative loss, 7.8 acre-feet of water lost with the mined product (which represents 267,931 tons of mined product), and 2.8 acre-feet of water used for dust control can be found on the attached table. Phreatophyte credits of 24.1 acre-feet per year . have been applied to this plan, which reduced the anticipated net depletions to 198.48 acre-feet per year. The proposed source of replacement for this pit is 98.1 acre-feet of historic stream delivery from the dry-up of 33.7 acres of land historically irrigated with five shares of Greeley Irrigation Company's interests in Greeley Canal No. 3 and Fossil Creek Reservoir diverted from the Cache la Poudre River and previously used for irrigation of the mined property. The values