In this Act, unless the context otherwise requires,—

(a) “Board” means the Central Board or a State Board;

(b) “Central Board” means the Central Pollution Control Board constituted under section 3;

(c) “member” means a member of a Board and includes the chairman thereof;

(d) “occupier”, in relation to any factory or premises, means the person who has control over the affairs of the factory or the premises, and includes, in relation to any substance, the person in possession of the substance;

(e) “pollution” means such contamination of water or such alteration of the physical, chemical or biological properties of water or such discharge of any sewage or trade effluent or of any other liquid, gaseous or solid substance into water (whether directly or indirectly) as may, or is likely to, create a nuisance or render such water harmful or injurious to public health or safety, or to domestic, commercial, industrial, agricultural or other legitimate uses, or to the life and health of animals or plants or of aquatic organisms;

(f) “prescribed” means prescribed by rules made under this Act by the Central Government or, as the case may be, the State Government;

(g) “sewage effluent” means effluent from any sewerage system or sewage disposal works and includes sullage from open drains;

(h) “State Board” means a State Pollution Control Board constituted under section 4;

(i) “State Government” in relation to a Union territory means the Administrator thereof appointed under article 239 of the Constitution;

(j) “stream” includes—

(k) “trade effluent” includes any liquid, gaseous or solid substance which is discharged from any premises used for carrying on any industry, operation or process, or treatment and disposal system, other than domestic sewage.