35.15.230 Regulations – Mining on river and stream shorelines.
(1) Mining within the active channel or channels (a location waterward of the ordinary high water mark) of a river may be permitted as a conditional use, consistent with Table 2-2, when consistent with this Program and the following:
(a) Removal of specified quantities of sand and gravel or other materials at specific locations will not adversely impact the natural processes of sediment transport for the river system as a whole; and
(b) The mining and any associated permitted activities will not have adverse impacts to habitat for priority species nor cause a net loss of ecological functions of the shoreline.
(2) Specific studies accompanying applications for in-river mining shall demonstrate that no adverse flood, erosion, or other adverse environmental impacts occur either upstream or downstream of extraction sites. Mining extraction amounts, rates, timing, and locations shall be based on a scientifically determined sediment budget adjusted periodically according to data provided by a regular monitoring plan.
(3) Aggregate washing and ponding of wastewater are prohibited in floodways.
(4) Storage of mining equipment or materials within the FEMA floodway is prohibited during the flood season (November 1st through March 1st); provided, that temporary stockpiling is permitted during working hours if all such materials are removed from the floodway at the end of each day’s operation.
(5) All applicable permits and approvals, including but not limited to a Hydraulic Project Approval (HPA) from the Department of Fish and Wildlife, shall be obtained prior to commencement of any mining activity and all applicable provisions attached thereto shall be adhered to.
(6) Open pit mining may be permitted in a floodplain as a conditional use when consistent with this Program and when all of the following criteria are met:
(a) All pits and other operations should be located outside of the channel migration zone.
(b) All pits of each operation should be located and excavated to a depth to function as a self-flushing chain of lakes whenever the pits are overtopped by floods in order to prevent eutrophication and fish entrapment.
(c) The entire operation should be sized and designed so that additional bank erosion, catastrophic changes in channel location, or adverse impact to fish resources or water quality will not likely result in the long term.
(d) The scale and mode of operation will not have adverse impacts on fish resources, water quality, and recreation resources, nor adversely impact a stream’s natural capacity to erode, shift, accrete, and/or flood.
(e) All equipment, works, and structures are designed to withstand flooding without becoming a hazard in themselves nor causing adverse impacts on shore features, without the necessity for shore stabilization structures.
(f) All structures or equipment which are not floodproofed shall be located outside of the 100-year floodplain during the flood season (November 1st through March 1st); provided, that such equipment is permitted during daily operations.
(7) Overburden or other mining spoil or nonputrid solid wastes shall comply with the fill policies of this Program, and be disposed of in an approved manner to protect shoreline ecological functions and processes, other uses, and aesthetic values.