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n <br />Ms. Jennifer Lindahl, P.E. Page 3 of 4 <br />June 5, 2015 <br />Larimer Pits will not exceed the amounts decreed in case no. 2000CW142 during the mining of Pit <br />No. 21. In case no. 2000CW142, the "Larimer Pits" are defined as Pit Nos. 13, 14, 15, 18, and 20. <br />A maximum of 20,000 tons of aggregate may be produced at the Larimer Pits annually. The <br />material is mined below the ground water table, but in a dewatered state, and is washed; therefore <br />the water retained in the mined product is considered to be 4.0% of the mined material by weight <br />(9.6 gallons per ton). A maximum of 125,000 cubic yards of concrete may be produced at the <br />Larimer Pits annually. Water consumption for concrete production is estimated at 3,750,000 gallons <br />based on a consumption rate of 30 gallons of water per cubic yard of concrete. A maximum of <br />1,440,000 gallons of water may be used for dust control at the Larimer Pits annually. Dust control is <br />considered to be 100% consumptive. Consumption from mining uses at Pit Nos. 13, 14, 15, 18, 20, <br />and 21 will therefore be limited to 16.52 acre-feet per year (see Table 2). The monthly ground water <br />depletions from Pit No. 21 will be lagged to the Big Thompson River using AWAS with the parameters <br />identified for Pit No. 21 above. <br />LRM will replace all depletions that impact the stream during mining operations and those <br />that lag out beyond the completion of mining at Pit No. 21 with their available replacement supplies, <br />discussed below. <br />Proposed Replacements <br />LRM's available replacement supplies include a portion of 120 Barnes Ditch inches diverted <br />from the Big Thompson River and previously used for irrigation of the mined property and a portion <br />of 200 acre-feet per year of fully consumable water leased from the City of Loveland. <br />An amount of 16.52 acre-feet of the irrigation season credits associated with the Barnes Ditch <br />inches were dedicated to replace mining depletions at the Larimer Pits and will also be used to <br />replace consumption from mining uses at Pit No. 21 pursuant to a substitute water supply plan to be <br />obtained by LRM prior to commencement of mining at Pit No. 21. The Barnes Ditch inches were <br />quantified and changed for multiple uses in case no. 2000CW143, including augmentation of <br />depletions resulting from operations at the Larimer Pit site. The 120 Barnes Ditch inches were <br />historically used to irrigate varying amounts of land up to 243 acres, all of which have since been <br />removed from irrigation. The decree in case no. 2000CW143 found the irrigation season credits for <br />the entire 120 Barnes Ditch inches to be 243.5 acre-feet with a winter return flow requirement of <br />6.70 acre-feet. Credits will be bypassed at the Barnes Ditch headgate and left in the Big Thompson <br />River or diverted through LRM Pond Nos. 1 and 2 and returned to the Big Thompson River at the <br />water commissioner's discretion on a monthly or more frequent basis. Deliveries are limited to the <br />period of May 8 through October 12 of each year. <br />Replacement for depletions during the period of September through April and at times when <br />the Barnes Ditch inches are out -of -priority will be met by releases of fully consumable water leased <br />from the City of Loveland. LRM has a total of 200 acre-feet of fully consumable water available <br />pursuant to a lease agreement dated January 13, 1998. The subject lease is valid for a term of 25 <br />years, ending on December 31, 2022. LRM has dedicated 100.66 acre-feet of this leased water to the <br />augmentation plan decreed in case no. 2009CW105. The remaining 99 acre-feet are currently <br />dedicated for use in the Loveland Ready -Mix Concrete, Inc. Combined Substitute Water Supply Plan, <br />