Rule 26-2-1.62 - STORAGE TANKS, SOUR CRUDE OIL On all storage tanks or batteries of storage tanks where there is stored, either permanently or temporarily, crude oil, distillate or condensate produced from an oil well or a gas well where any hydrogen sulphide (H2S) is produced in conjunction with the fluid such that the vapor or fumes from such liquid, when measured in the free gas space inside the tank, has a hydrogen sulphide (H2S) concentration in excess of twenty (20) ppm, as measured using a hydrogen sulphide (H2S) detection device of a type capable of measuring hydrogen sulphide concentrations ranging from zero (0) to fifty (50) ppm, the following safety provisions shall pertain, in addition to all other applicable statewide or special field rules:
A. All access hatches to the tanks capable of being readily operable shall be kept closed securely at all times except when necessary for such hatches to be open for inspection and gauging.B. All stairways or ladders leading from ground level to the top of each of such tank or tanks shall have installed thereon a gateway or doorway permanently affixed in such a manner as to impede further ascent of such ladder or gangway to the top of such tank or tanks except through the open gate or door. The gateways or doorways shall be kept securely locked except when necessary to gauge or inspect such tanks.C. All fumes and vapor in such tank or tanks shall be suitably recovered in a vapor recovery unit or flared to the atmosphere. If flared to the atmosphere, fumes and vapor shall be flared through a flare stack with a permanent pilot attached thereon so that the emissions do not exceed applicable air quality standards.D. Vapor recovery units shall be suitably provided with standby facilities for flaring of fumes and vapors to the atmosphere in the event of an upset. Such standby venting and flaring facilities shall be the same as those provided for in Paragraph C above.E. A self-contained breathing apparatus shall be worn and used by all personnel passing through the gateway or doorway provided in Paragraph B above at all times while on the ladder or on top of the tank or tanks.F. All such storage tanks and the nearby surrounding area shall be conspicuously marked and posted in a manner advising of the presence of potentially lethal fumes and vapors.G. This rule shall take effect on and after July 1, 1971; provided, however, that owners and operators of existing installations shall have sixty (60) days from said date in which to comply with these rules without incurring any penalty.H. Penalty: Any person, firm or corporation willfully violating any of these rules and regulations shall be punished as provided by law.I. Provided, however, that storage tank or tanks within the boundaries of a petroleum refinery or petrochemical plant shall be exempt from the provisions of this rule.MCA Section 53-1-17(3) (1972)