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Journey Ventures Pit SWSP Page 2 of 5 <br /> July 24, 2024 <br /> replacement for the losses within the lined reservoir and replace any captured precipitation within the <br /> reservoir as required under the 19CW3088 decree. <br /> You have provided monthly breakdown of thedepletionsduringthis plan period of 6.25 acre-feet of water <br /> consumed fordust control as shown on attached Table 1. Water used for dust control will be pumped from <br /> the lined reservoir from water collected from precipitation. The Applicant must measure all water diverted <br /> for dust control and replace all depletions resulting from such diversions. <br /> The IDS AWAS stream depletion model, using the alluvial aquifer option,was used to determine the lagged <br /> depletions to the South Platte River from past mining operations.The following parameters were used in <br /> the model: transmissivity (T) = 100,000 gallons per day per foot, distance (X) from the centroid of the <br /> surface of the exposed ground water to the river = 4,766 feet, distance (W) from the aquifer boundary <br /> through the exposed ground water to the river channel = 9,500 feet, and specific yield (SY) = 0.2. The <br /> lagged depletions include actual depletions during this plan period plus any remaining 5% of depletions <br /> remaining due to past mining operations wrapped back into this SWSP plan period totaling 9.78 acre-feet, <br /> as shown in attached Table 2. <br /> Since all depletions during this plan period will occur within the boundaries of the slurry wall from <br /> precipitation collection and the gravel pit borders a year-round live seep, the Applicant has assumed that <br /> such depletions are instantaneous. Therefore, the total depletions during this plan period are estimated <br /> to total 16.03 acre-feet, as shown in attached Table 2, which include the 9.78 acre-feet of wrapped lagged <br /> depletions from pre April 2022 operations. <br /> Replacements <br /> The operator proposes to provide replacement for this pit using fully consumable water leased from the <br /> Central Colorado Water Conservancy District ("CCWCD"). A copy of the lease agreement with CCWCD for <br /> up to 17.84 acre-feet for one year from April 1, 2024 through March 31, 2025 was provided to this office <br /> with the SWSP request and is attached to this letter. The leased water includes additional water to cover <br /> transit losses, based on a transit loss of 0.5 percent per mile and 6.8 miles. <br /> Water will be released from the Geisert Pit, located along the Cache La Poudre River in Greeley and <br /> approximately 6.8 miles upstream from the Journey Ventures Pit. The Ogilvy Ditch headgate on the Cache <br /> la Poudre River is a potential summer dry-up point that is located between Geisert Pit and the location of <br /> the Journey Venture Pit depletion point, in the SE '/a of Section 7, Township 5 North, Range 64 West of the <br /> 61" P.M. Central has a bypass structure at the Ogilvy Ditch headgate to pass augmentation flows by the <br /> Ogilvy at times when the Ogilvy is diverting the entire flow of the Cache la Poudre River. Alternatively, <br /> CCWCD will release water for the Nissen Pit, located along the lower South Platte just upstream of the <br /> confluence with the Cache La Poudre River. Central must include in their accounting the amount of water <br /> delivered through Central's bypass structure for use in this plan. <br /> Long Term Augmentation <br /> In accordance with the letter dated April 30, 2010 (copy attached) from the Colorado Division of <br /> Reclamation, Mining, and Safety ("DRMS"), all sand and gravel mining operators must comply with the <br /> requirements of the Colorado Reclamation Act and the Mineral Rules and Regulations for the protection of <br /> water resources. The April 30, 2010 letter from DRMS requires that you provide information to DRMS to <br /> demonstrate you can replace longterm injurious stream depletions that result from mining related exposure <br /> of groundwater. The DRMS letter identifies four approaches to satisfy this requirement. <br /> In accordance with approach nos. 1 and 3, of the DRMS April 30, 2010 letter the Applicant obtained a bond <br /> for $487,550 through the DRMS for the current mining phases, TR3 and 1, 2, 3 and 4 of this site to assure <br />