As used in this chapter:

    “Area of regional significance” means an area designated by the State Mining and Geology Board which is known to contain a deposit of minerals, the extraction of which is judged to be of prime importance in meeting future needs for minerals in a particular region of the state within which the minerals are located and which, if prematurely developed for alternate incompatible land uses, could result in the premature loss of minerals that are of more than local significance.

    “Bench” means a level area that interrupts a slope, constructed for such purposes as to retain or limit rock falls, provide working surfaces or access, and to control erosion.

    “Borrow pits” means excavations created by the surface mining of rock, unconsolidated geologic deposits or soil to provide material (borrow) for fill elsewhere.

    “Critical gradient” means the maximum stable inclination of an unsupported slope under the most adverse conditions that it will likely experience, as determined by current engineering technology.

    “Compatible land uses” means land uses inherently compatible with mining and/or that require a minimum public or private investment in structures, land improvements, and that may allow mining because of the relative economic value of the land and its improvements. Examples of such uses may include, but shall not be limited to, very low density residential, geographically extensive but low impact industrial, recreational, agricultural, silvicultural, grazing and open space.

    “Exploration” or “Prospecting” means the search for minerals by geological, geophysical, geochemical or other techniques, including, but not limited to, sampling, assaying, drilling or any surface or underground works needed to determine the type, extent, or quantity of mineral present.

    “Haul road” means an internal road along which material is transported from the area of excavation to the processing plant or stock pile area of the surface mining operation.

    “Haul route” means an external road along which previously excavated, processed or stockpiled material is transported to an off-site area.

    “Idle” means surface mining operations curtailed for a period of one year or more, by more than ninety (90) percent of the operation’ s previous maximum annual mineral production, with the intent to resume those surface mining operations at a future date.

    “Incompatible land uses” means land uses inherently incompatible with mining and/or that require public or private investment in structures, land improvements, and landscaping and that may prevent mining because of the greater economic value of the land and its improvements. Examples of such uses may include, but shall not be limited to, high density residential, low density residential with high unit value, public facilities, geographically limited but impact intensive industrial, and commercial.

    “Mine” includes all mineral bearing properties of whatever kind or character, whether underground, or in a quarry or pit, or any other source from which any mineral substance is or may be obtained.

    “Mined lands” includes the surface, subsurface, and groundwater of an area in which surface mining operations will be, are being, or have been conducted, including private ways and roads appurtenant to any such area, land excavations, workings, mining waste, and areas in which structures, facilities, equipment, machines, tools or other materials or property which result from, or are used in, surface mining operations are located.

    “Minerals” means any naturally occurring chemical element or compound, or groups of elements and compounds, formed from inorganic processes and organic substances, including, but not limited to, coal, peat, and bituminous rock, but excluding geothermal resources, natural gas, and petroleum.

    “Mining waste” or “mine waste” includes the residual of soil, rock, mineral, liquid, vegetation, equipment, machines, tools, or other materials or property directly resulting from, or displaced by, surface mining operations.

    “Operator” means any person who is engaged in surface mining operations, or who contracts with others to conduct operations on his behalf, except persons who are engaged in surface mining operations as employees with wages as their sole compensation.

    “Overburden” means soil, rock, or other materials that lie above a natural mineral deposit or in between deposits, before or after their removal by surface mining operations.

    “Permittee” means any person or operator who possesses a valid permit to operate a surface mine in Alameda County that meets the requirements of this chapter and SMARA. When the operator and the permittee are not the same person, the operator shall identify the permittee to the county.

    “Person” means any individual, firm, association, corporation, organization, partnership, or any local agency as defined by Government Code Section 53090 et seq.

    “Reclamation” means the combined process of land treatment that minimizes disruption or alteration of groundwater movement, water quality degradation, air pollution, damage to aquatic or wildlife habitat, flooding, erosion, sedimentation, and other adverse effects from surface mining operations, including adverse surface effects incidental to underground mines, so that mined lands are reclaimed to a usable condition that is readily adaptable for alternate land uses, and so that adverse impacts on groundwater resources are mitigated, and no danger to public health or safety is created. The process may extend to affected lands under the control of the operator surrounding mined lands, and may require backfilling, grading, resoiling, revegetation, soil compaction, erosion and sediment control, stabilization, restoration of groundwater recharge areas, or other measures.

    “State policy” means the State Policy for the Reclamation of Mined Lands adopted pursuant to Section 2755 of the Public Resources Code.

    “Stream bed skimming” means excavation of sand and gravel from stream bed deposits above the mean summer water level or stream bottom, whichever is higher.

    “Surface mining operations” or “Mining operations” means all, or any part of, the process involved in the mining of minerals on mined lands by removing overburden and mining directly from the mineral deposits, open-pit mining of minerals naturally exposed, mining by the auger method, dredging, quarrying, or surface work incident to an underground mine. Surface mining operations include, but are not limited to:

    1.    In-place distillation, retorting or leaching;

    2.    The production and disposal of mining waste;

    3.    The removal of overburden;

    4.    Prospecting and exploratory activities;

    5.    Borrow pit activity;

    6.    Streambed skimming; and

    7.    Segregation and stockpiling of mined materials (and recovery of same).

    “Topsoil” means the upper part of the soil profile that is relatively rich in humus, which in the field of agronomy is known as the A-1 horizon of the soil profile. (Ord. 99-60 (part): prior gen. code §§ 8-113.0— 8-113.13)