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with credits (historic consumptive use) will be replaced in time <br />and location with augmentation water. <br />8. Based upon engineering data submitted by the <br />Applicants, it would appear that total annual replacement need <br />for augmentation at post-mining build-out will be 5.09 acre-feet <br />of water. while the mine is active additional augmentation of <br />water will be required to offset the consumptive use of entrapped <br />water in the mined product. The final operating year of the mine <br />will be the highest total augmentation requirement estimated at <br />6.56 acre-feet of water, including the losses due to any storage <br />vessel used to store the augmentation water. <br />9. Applicants plan on building an augmentation pond to <br />receive water historically utilized under the Sunrise Ditch <br />Priority No. 13, and to store the water for release during those <br />months when and if a call is placed upon the river. This plan <br />will then contemplate a change of use of a portion of the Sunrise <br />Ditch appropriation to augmentation use adjusted to annual <br />requirements on the river. <br />10. The Applicant intends to proceed with the <br />construction of an on-site water storage pond to satisfy the <br />requirements for winter replacement water so that gravel mining <br />can be initiated. This augmentation plan will provide the long <br />term, permanent solution to winter losses. Due to the slow <br />development of the pond/mine site, it is the Applicant's stated <br />intent to use on-site overburden for the construction of the <br />storage pond. The pond will be constructed and operational prior <br />to the FWS area of the mine exceeding 5 acres in size. It is <br />anticipated that this will provide sufficient selectively <br />excavated material for the pond's construction. The augmentation <br />storage pond is to be approximately one acre in water surface and <br />have a long term release capacity of 5.09 acre-feet of stored <br />water. To accommodate the release requirement, a storage right <br />of 6.56 acre-feet is required to account for the long term winter <br />time evaporative and leakage losses from the storage pond. <br />11. The augmentation pond will maintain the following <br />essential features to serve its function: An average of one net <br />acre water surface (set at 1/2 depth = 1 acre); a maximum of 2:1 <br />interior and exterior side slopes; hydraulic conductivity of the <br />pond soils should not exceed 5.0 E-7 cm/sec; a minimum of one <br />foot thick soil lines; outlet device easily operated by the <br />division capable of releasing the entire pond; total pond depth <br />8.5 feet (including freeboard); a full build-out of the gravel <br />pit during year 15 operating season the pond is to be full by <br />approximately November 7; a staff gauge and capacity table to <br />measure pond volume. <br />12. As a result of the operation of the foregoing plan <br />for augmentation, replacement water will be provided to the <br />-3- <br />