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reclamation does not include backfilling or lining, the applicant can still provide <br />sufficient bonding (through the Division of Minerals and Geology) to cover lining or <br />backfilling during operation. <br />9. The effect of stream depletions from the operation shall be evaluated. It will not be <br />assumed that depletions occur instantaneously unless the outside edge of the pit is <br />located within 100 feet from the river or site specific geologic and hydrologic <br />information warrants this assumption. Generally, timing of depletions may be <br />calculated using Glover techniques [parallel drain theory, stream depletion <br />factor(SDF)], or numeric modeling. Special procedures may be necessary to analyze <br />depletions and injury on intermittent streams. <br />10. Historical native vegetation (including phreatophytes) consumptive use may be <br />credited against monthly gross evaporation only if engineering documentation is <br />included. The credit shall only be applied for the area under the free water surface <br />and cannot exceed the amount of gross evaporation. Documentation of the <br />vegetative growth shall be based on aerial and perspective photographs depicting <br />the growth. Consumptive use analysis of this growth shall be based upon published <br />engineering studies acceptable to our office and engineering analysis of site specific <br />information for the type of growth, ground water depth, and soil information. <br />11. The historical consumptive use credit may be assigned to precipitation or ground <br />water. The amount of consumptive use credit from precipitation and ground water <br />during the growing season can not exceed the total potential consumptive use of the <br />native vegetation. No benefit is given for excess consumptive use credits. The net <br />depletion will be calculated as gross evaporation minus historical consumptive use. <br />The historical consumptive use for non-irrigated native sites without phreatophytes <br />or subirrigation is equal to the effective precipitation which is equal to 70% of total <br />precipitation for each month. Higher maximum effective precipitation amounts must <br />be supported with engineering documentation. The maximum effective precipitation <br />must be adjusted accordingly for sites with historical irrigation or subirrigation. <br />REPLACEMENT SOURCES <br />12. Replacement water to compensate out-of-priority depletions must be available <br />either directly or by exchange in the proper quantity, quality, place and time to insure <br />that existing water rights are not injured. All plans, whether the pit has exposed <br />water or not, submitted to this office will be required to have concurrent replacement <br />water available in order to obtain approval from the State Engineer. <br />13. Plans for replacement generally utilize three primary sources of water to <br />compensate the stream system for depletions resulting from evaporation and mining <br />losses. These sources include direct flow water rights, reservoir storage, and <br />nontributary and transbasin water. Water right decrees and other pertinent <br />information regarding the replacement sources shall be included. The applicant shall <br />also provide signed lease agreements or recorded non-encumbered ownership <br />documents authorizing use of the proposed replacement sources. Although the <br />substitute water supply plan may be approved on a temporary basis using leased or