Tex. Water Code § 31.001

In this chapter:

(1) "Commission" means the Texas Commission on Environmental Quality.

(2) "Executive director" means the executive director of the Texas Commission on Environmental Quality.

(3) "Ground movement" means any horizontal or vertical displacement of the strata, including the earth surface, resulting from or related to activities of subsurface construction, operation, or use including subsidence, uplift, shear along shaft walls, or other disturbance of the natural strata or land surface.

(4) "Industrial waste" means waterborne liquid, gaseous, or solid substances that result from any process of industry, manufacturing, trade, or business, including runoff water from mined materials and associated solids storage or disposal areas.

(5) "Permit" means a subsurface excavation permit issued by the commission.

(6) "Person" means an individual, corporation, organization, government or governmental subdivision or agency, business trust, partnership, association, or any other legal entity.

(7) "Pollution" means alteration of the physical, thermal, chemical, or biological quality of or the contamination of water in the state that:

(A) makes the water harmful, detrimental, or injurious to humans, animal life, vegetation, or property or to public health, safety, or welfare; or

(B) impairs the usefulness or the public enjoyment of the water for a lawful or reasonable purpose.

(8) "Spoils" means material removed from subsurface excavations and brought to the land surface for storage or disposal.

(9) "Subsurface excavation" means shafts and underground workings but does not include excavations associated with the exploration, development, and production of oil, gas, or geothermal sources and does not include excavations designed to serve as permanent tunnels.

(10) "Underground workings" means an excavation below the land surface connected to and associated with shafts, including adits, raises or inclines, tunnels, rooms, drifts, shaft stations, and chambers, that:

(A) penetrate into, through, or below the uppermost water-bearing strata; and

(B) are used for access, transportation of persons and materials, ventilation, storage, or removal of materials.

(11) "Water" or "water in the state" means groundwater, percolating or otherwise, lakes, bays, ponds, impounding reservoirs, springs, rivers, streams, creeks, estuaries, marshes, inlets, canals, the Gulf of Mexico inside the territorial limits of the state, and all other bodies of natural and artificial surface water that are inland or coastal, fresh or salt, and navigable or nonnavigable and includes the beds and banks of all watercourses and bodies of surface water that are wholly or partially inside or bordering the state or inside the jurisdiction of the state.

(12) "Water inflow" means water movement into subsurface excavations from surface or subsurface sources, including:

(A) inrushes from underground isolated water pockets and from fault conduits; and

(B) flow from:

(i) primary and natural or induced secondary permeability;

(ii) manmade conduits such as shafts, adjacent underground workings, subsidence fractures, and open, plugged, or abandoned boreholes; and

(iii) surface flooding.