OAR 690-512-0010: Definitions

Unless specified in these rules the definitions in OAR 690-300-0010 apply to the below rules: (1) “Adaptive Management Checkpoint” means the scheduled interval at which the Department evaluates changes in groundwater levels and determines if adjustments to scheduled reductions in groundwater use are required as described in OAR 690-512-0080. (2) “Exempt Groundwater Uses” are those defined in ORS 537.545. (3) “Groundwater Level Change Envelope” means the modeled trajectory for groundwater levels to achieve the target groundwater level trend by 2058. A groundwater level change envelope is modeled for each subarea including the median, 10th, 25th, 75th, and 90th percentiles relative to the modeled groundwater levels in 2028. The envelope describes the range of values that will be used to inform the adaptive management process in OAR 690-512-0080. The trajectories are modeled using “Groundwater model of the Harney Basin, southeastern Oregon” by S.B. Gingerich, D.E. Boschmann, G.H. Grondin, and H.J. Schibel, 2024, U.S. Geological Survey Scientific Investigations Report 2024-5017. (4) “Initial Allotment” means the maximum annual volume of water that may be used by each groundwater right upon completion of the contested case. (5) “Permissible Total Withdrawal” is the annual volume of groundwater pumping the Department has determined can achieve the target groundwater level trend by 2058 when following the schedule of reductions defined in OAR 690-512-0070. The unit of measure for the permissible total withdrawal is acre- feet. (6) “Public Uses” are those uses defined in ORS 537.332. (7) “ Regulated off” and “reduce” means the act of limiting groundwater use through a regulatory order. (8) “Subarea” means an administratively defined portion of the critical groundwater area to which corrective control provisions under ORS 537.735(3)(a)-(f) may be applied. (9) “Target Groundwater Level Trend” means the goal for the rate of change in groundwater levels within a subarea of the critical groundwater area. (10) “Totalizing flow meter” is an instrument used to measure and display both the instantaneous flow rate, and the total volume of groundwater produced from a well.