Petroleum Act 1923

Every lessee and every holder of an authority to prospect unless in any case wholly or partially excused by the Minister from so doing, shall properly case each well with metal casing in accordance with the best approved methods, landing and effectually cementing 1 or more strings of the casing in clay or other water-impervious strata and generally shall take all such steps as may be reasonably necessary for effectually shutting off the escape of all water and for effectually preventing any water from penetrating any petroleum deposits, and for effectually preventing any petroleum from penetrating any aquifer.