(1) In the numerous basin closure areas in Montana, the department cannot process an application unless it qualifies as a basin closure exception.

(2) An applicant must provide a written summary of their application information explaining how their application meets the basin closure exceptions and why their application located in a basin closure area can be processed.

(3) The department will determine whether an application in a basin closure area can be processed based on the information received from the applicant and will document its findings before it will review the application to determine whether it is correct and complete.

(4) While the department may determine that an application located in a basin closure area can be processed, an objector is able to refute the department's determination.

(5) In a basin closure area, evaporation losses must be mitigated.

(6) Augmentation plans are allowed in basin closure areas. An augmentation plan must mitigate the effects to the surface water source that would be depleted because of a proposed application.

(7) Augmentation must occur in the depleted reach and during the season of depletion.

(8) An augmentation plan must include a measuring plan to ensure that the source being depleted is receiving the benefits of the augmentation.

(9) If an augmentation plan requires more than one application, all applications will be processed simultaneously. If any of the augmentation applications is terminated or denied, all related applications will be terminated or denied.

(10) If an augmentation plan includes the filing of a Notice of Completion of Groundwater Development, the water must be from a nontributary source. The Notice of Completion must be filed with the department as soon as the water is used for augmentation.

(11) In basin closure areas that allow applications for groundwater that is not immediately or directly connected to surface water, information must be included in the document required in (2) demonstrating that the application qualifies as a groundwater exception.

(12) The department will not determine an application to be for a permit to appropriate groundwater unless the department can determine from the information provided that the cone of depression or zone of influence of a pumping well will not induce surface water infiltration during the proposed period of diversion.

(13) The department hydrologist shall make a written determination that the evidence submitted by an applicant is sufficient on which to base a determination that the proposed source aquifer is not hydraulically connected or if hydraulically connected to surface water, will not induce surface water infiltration.

(14) An applicant must address whether the source aquifer is hydraulically connected to any surface water sources that lie within an estimated or actual delineated zone of influence. An applicant may use the results of an appropriate nearby aquifer test to approximate the zone of influence. Depending on circumstances, such as proposed flow rate and volume, cyclic pumping, well depth, or distance to surface water, an applicant may be able to demonstrate that there is not nor will there be a hydraulic connection to surface water when water is pumped at the proposed flow rate during the period of diversion.

(a) High and low transmissivity and storativity values can be evaluated and used to estimate a zone of influence. The applicant must determine if the source aquifer is hydraulically connected to surface water within the delineated zone of influence.

(b) Relative or absolute elevations of groundwater levels and beds of surface water sources are needed to evaluate whether a hydraulic connection exists.

(c) Water level data may be obtained from existing wells located within the zone of influence or at the surface water source.

(d) If existing wells are not available, the installation of small diameter wells, pits, wellpoints, or piezometers, including those adjacent to or in the surface water source, can be used to determine the existence of a hydraulic connection.

(e) If an applicant demonstrates that the static groundwater level is greater than ten feet below the bed of a surface water source, the source aquifer is not considered hydraulically connected to surface water at that location. Further testing for induced surface water infiltration at the tested location is not required.

(f) If an applicant demonstrates that the static groundwater level is less than ten feet below the bed of a surface water source, additional proof is required to show whether the source aquifer is hydraulically connected to surface water. Additional proof must include an evaluation of capillary pressure, saturation, and unsaturated flow between the bed of the surface water source and the water table, and diurnal and seasonal fluctuations of static water levels. If additional proof is not provided, the source aquifer is considered to be hydraulically connected to surface water at that location. Further testing must be conducted to determine whether pumping the proposed well will induce surface water infiltration during the proposed period of diversion.

(15) An aquifer test must be conducted using methods described in ARM 36.12.121 that will determine the aquifer properties needed to determine the zone of influence for the period of diversion and the potential for drawdown to induce infiltration of surface water within the zone of influence.

(a) One or more observation wells may be needed to measure groundwater levels between the proposed production well and surface water sources and to determine hydraulic gradients before and during aquifer testing.

(b) Staff gage(s) must be installed in surface water source(s) adjacent to the observation well(s) to monitor stage(s) during the aquifer test for comparison with groundwater level(s) .

(c) Relative or absolute elevations of groundwater levels and surface water stages must be compared to determine whether the hydraulic gradient between the source aquifer and gaining surface water sources is reversed or whether the hydraulic gradient between losing surface water sources and the source aquifer is steepened. The occurrence of either during the aquifer test constitutes induced surface water infiltration.

(d) To evaluate whether induced surface water infiltration will occur during the period of diversion, an applicant must project drawdown to the surface water sources for the period of diversion using aquifer properties determined from the aquifer test. Analytical equations, an analytical groundwater flow model, or a numerical groundwater flow model may be used to evaluate whether induced surface water infiltration will occur.

(e) An applicant must evaluate whether a surface water body or reach is losing or gaining to evaluate whether a proposed well will induce surface water infiltration.

(i) If the applicant projects that drawdown will reach a losing surface water source that is hydraulically connected to groundwater during the period of diversion, the department will determine that pumping the proposed well will induce surface water infiltration.

(ii) For gaining surface water sources, the hydraulic gradient must be compared with the slope of the cone of depression that would be created during the period of diversion. If the comparison shows that the slope of the cone of depression is greater than the hydraulic gradient, the department will determine that pumping the proposed well will induce surface water infiltration.

(16) For groundwater pits, the department will determine that evaporation losses do not induce surface water for all infiltration. If water is being pumped from the pit, then a hydraulic analysis is required to determine if pumping will induce surface water infiltration.