2013-03-12_HYDROLOGY - M1977439 - Laserfiche WebLink

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Mr. Heintz and Ms. Wynne Upper Poudre Combined SWSP March 12, 2013 Page 4 projected, MMM may supplement their replacement supplies with other sources subject to the Division Engineer's approval. From 2006 to 2012, 5.75 Taylor and Gill Ditch shares have been diverted into the recharge pond to produce accretions to the stream for replacement purposes. In 2012, this resulted in a total delivery of 140.43 acre -feet. For 2013, 11 shares will be used to replace out -of- priority depletions through a combination of a recharge program and direct returns to the river. Using those shares, MMM projects to deliver 263.31 acre -feet to the river for direct replacement and 196.41 acre -feet to recharge. The evaporation losses from the recharge pond during this approval period are estimated at 2.57 acre -feet (see attached Table 5). Deducting appropriate losses and return flow requirements, this operation will create a total of 95.40 acre -feet of recharge credits and 140.37 acre -feet of direct flow credits during 2013. See Table 5 for a monthly breakdown of these credits. This SWSP relies on the average historical farm headgate delivery, consumptive use, and associated return flow analysis that was performed and approved in its previous SWSPs. The historic average farm headgate delivery was determined to be 41.79 acre -feet per share. This historic consumptive use credit was determined to be 21.36 acre -feet per share. Table 4 Column (E) provides the return flow obligation factors which will be used to determine return flows during the irrigation and non - irrigation season. Return flow obligations will be calculated based on the actual timing of diversions into recharge and direct returns. A monthly breakdown of the stream depletions from the mining operation as well as the replacements made by lagged timing of the historical consumptive use credit is shown in the attached Table 5. Long Term Augmentation In accordance with the letter dated April 30, 2010 (copy attached) from the Colorado Division of Reclamation, Mining, and Safety ( "DRMS "), all sand and gravel mining operators must comply with the requirements of the Colorado Reclamation Act and the Mineral Rules and Regulations for the protection of water resources. The April 30, 2010 letter from DRMS requires that you provide information to DRMS to demonstrate you can replace long term injurious stream depletions that result from mining related exposure of ground water. The DRMS letter identifies four approaches to satisfy this requirement. In accordance with approach nos. 1 and 3, you have provided bonds through DRMS which may be used to backfill or line areas of exposed ground water. According to the mining permits with DRMS, the reclamation plan for the Home Office Pit and North Taft Hill Expansion Site is to create unlined ground water ponds. These two sites also have conditional water storage rights for future lined reservoirs in water court case 92CW157. For the Overland Ponds site, the DRMS mining permit reclamation plan is to create lined reservoirs and the site has pending water storage rights for future lined reservoirs in water court case 00CW251. If reclamation at any mine site produces a permanent water surface exposing ground water to evaporation, an application for a plan for augmentation must be filed with the Division 1 Water Court at least three years prior to the completion of mining to include, but not be limited to, long -term evaporation losses. If a lined pond results after reclamation, replacement of lagged depletions shall continue until there is no longer an effect of stream flow. A summary of the final reclamation plan and the current posted bond amounts for each site is shown on the next page.