SECTION 165:10-3-16. Operation in hydrogen sulfide areas  


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  • (a)   Applicability. Each operator who conducts operations as described in this subsection shall be subject to this Section and shall provide sufficient safeguards to protect the general public from the occupational exposure limit of gas with a hydrogen sulfide content of 20 or more ppm and the immediate danger to life and health from a release of gas with a hydrogen sulfide content of 100 or more ppm:
    (1)   Operations including drilling, working over, producing, injecting, gathering, processing, transporting, and storage of hydrocarbon fluids that are part of, or directly related to, field production, transportation, and handling of hydrocarbon fluids that contain gas in the system which has hydrogen sulfide as a constituent of the gas to the extent as specified in (b) of this Section. The Commission may fine an operator up to $5,000.00 for any violation of this Section.
    (2)   This Section shall not apply to:
    (A)   Operations involving processing oil, gas, or hydrocarbon fluids which are either an industrial modification or products from industrial modifications, such as refining, petrochemical plants, or chemical plants.
    (B)   Operations involving gathering, storing, and transporting stabilized liquid hydrocarbons.
    (C)   Operations where the concentration of hydrogen sulfide in the system is 20 ppm or less.
    (b)   General provisions.
    (1)   Each operator shall determine the hydrogen sulfide concentration in the gaseous mixture in the operation or system. Tests shall be made in accordance with industry standards or other methods approved by the Commission.
    (2)   For all operations subject to this Section, the radius of exposure shall be determined by the following Pasquill-Gifford equations or by other methods approved by the Commission such as air dispersion models accepted or approved by the U.S. Environmental Protection Agency:
    (A)   For determining the location of the 100 ppm radius of exposure: x = [(1.589)(mole fraction H2S)(Q)] to the power of (.6258).
    (B)   For determining the location of the 300 ppm radius of exposure: x = [(0.6743) (mole fraction H2S) (Q)] to the power of (.6258).
    (C)   For determining the location of the 500 ppm radius of exposure: x = [(0.4546)(mole fraction H2S)(Q)] to the power of (.6258); Where: x = radius of exposure in feet; Q= maximum volume determined to be available for escape in cubic feet per day; H2S = mole fraction of hydrogen sulfide in the gaseous mixture available for escape.
    (3)   The volume used as the escape rate in determining the radius of exposure shall be that specified below as is applicable:
    (A)   The maximum daily volume rate of gas containing hydrogen sulfide handled by that system for which the radius of exposure is calculated.
    (B)   For existing gas wells, the current adjusted open flow rate or the operator's estimate of the well's capacity to flow against zero back-pressure at the well head shall be used.
    (C)   For new wells drilled in developed areas, the escape rate shall be determined by using the current adjusted open-flow rate of offset wells or the field average current adjusted open-flow rate, whichever is larger.
    (D)   The escape rate used in determining the radius of exposure shall be corrected to standard conditions of 14.65 psia and 60° Fahrenheit.
    (4)   For drilling of a well in an area where insufficient data exists to calculate a radius of exposure but where hydrogen sulfide may be expected, then a 100 ppm radius of exposure equal to 3,000 feet shall be assumed. A lesser-assumed radius may be considered upon written request to the appropriate Conservation Division District Office setting out the justification for same.
    (5)   As used in this Section, a public area is defined as a dwelling place, business, church, school, hospital, school bus stop, government building, a public road, all or any portion of a park, city, town, village, or other similar area that can reasonably be expected to be populated by humans.
    (6)   As used in this Section, a public street or road is defined as any federal, state, county or municipal street or road owned or maintained for public access or use.
    (7)   As used in this Section, a rural residential subdivision is defined as an assemblage of 5 or more residential housing units per 10-acre tract.
    (8)   As used in this Section, a flare system is defined as a gas recovery process of well control for the flaring of gas through means of a closed system comprised of, but not limited to, a separator, compressor, flare lines, knock-out drum, sealed scrubber drum, back-pressure check valves, flare stack assembly and automatic ignitor.
    (9)   Facilities where the 100 ppm radius of exposure extends into a public area shall use materials for new construction, or modification of or repairs to existing facilities, subsequent to the effective date of this paragraph, selected and manufactured so as to be resistant to hydrogen sulfide stress cracking under operating conditions for which their use is intended.
    (A)   Other materials which are non-susceptible to hydrogen sulfide stress cracking, such as fiberglass and plastics, may be used in hydrogen sulfide service provided such materials have been manufactured and inspected in a manner which will satisfy applicable industry standards, specifications or recommended practices.
    (B)   Existing facilities which are in operation prior to the effective date of paragraph (b)(9), above, and where there has been no failure of existing equipment attributed to hydrogen sulfide stress cracking, shall satisfy the requirements of paragraph (b)(9) until such time as the facility experiences a failure.
    (10)   The handling and installation of materials and equipment used in hydrogen sulfide service are to be performed in such a manner so as to prevent hydrogen sulfide stress cracking.
    (c)   Storage tank provision. Storage tanks which are utilized as a part of a production operation, and which are operated at or near atmospheric pressure and where the vapor accumulation has a hydrogen sulfide concentration that when measured one (1) foot above the open tank thief hatch exceeds 100 ppm, shall be subject to the following:
    (1)   It shall not be necessary to determine a radius of exposure for storage tanks as described in this Section.
    (2)   A warning sign shall be posted at the facility which shall meet the following requirements:
    (A)   A sign shall be located within 50 feet of the facility and be of sufficient size to be readable from the road or at the entrance to the facility.
    (B)   The warning sign shall state at a minimum that hydrogen sulfide has been found and could be present.
    (C)   Signs constructed to satisfy paragraph (c)(1) shall use the language "Caution, Poisonous Gas May Be Present" using black and yellow colors, or "Danger Poison Gas (Hydrogen Sulfide)" using red and white colors or equivalent language. Colors shall satisfy Table 1 of American National Standards Institute Standard Z390.1-2017. Signs installed to satisfy paragraph (c)(1) must be compatible with Federal Occupational Safety and Health regulations.
    (3)   A wind indicator is to be located at the highest point of the tank battery site so that it may be seen from the entrance to the site.
    (4)   Fencing as a security measure is required when storage tanks are located inside the populated limits of a townsite or city or a rural residential subdivision, where conditions cause the storage tanks to be exposed to the public. In other areas where storage tanks may be considered to be a danger the Commission may require additional security measures.
    (5)   Vapor safety. A flare system, vapor recovery system or H2S stripping system shall be installed.
    (d)   Drilling, completion, workover and production operations. All operators whose operations are subject to this Section, and where the 100 ppm radius of exposure is in excess of 50 feet, shall be subject to the following:
    (1)   Warning and marker provision.
    (A)   For aboveground and fixed surface facilities, the operator shall post, where permitted by law, clearly visible warning signs on access roads or public streets, or roads which provide direct access to facilities located within the area of exposure.
    (B)   In populated areas such as townsites, cities or rural residential subdivisions where the use of signs is not considered to be appropriate, an alternative warning plan may be approved upon written request to the appropriate Conservation Division District Office.
    (C)   For buried lines subject to this Section, the operator shall comply with the following:
    (i)   A marker sign shall be installed at public road crossings on both sides of the road as close to the pipeline as possible.
    (ii)   Marker signs shall be installed along the line, when it is located within a public area or along a public road, at intervals frequent enough in the judgment of the operator so as to provide warning to avoid the accidental rupturing of line by excavation.
    (iii)   The marker sign shall contain the name of the operator and a 24-hour phone number (including area code), and shall indicate by the use of the words "Warning", "Caution", or "Danger" and "Poison Gas" that a potential danger exists. Markers installed in compliance with the regulations of the Federal Department of Transportation shall satisfy the requirements of this provision. Marker signs installed prior to June 12, 1987 shall be acceptable provided they are in good condition and indicate the existence of a potential hazard.
    (D)   In satisfying the sign requirement of this subsection, the following will be acceptable:
    (i)   Sign of sufficient size to be readable from the road or at the entrance to the facility.
    (ii)   New signs constructed to satisfy this subsection shall refer to (c)(2) of this Section.
    (2)   Security provision.
    (A)   Unattended fixed surface facilities shall be protected from public access when located within one-fourth (1/4) mile of a public area. This protection shall be provided by fencing the facility and locking the gate, the plugging of valve openings and removing the handles, or by other similar means approved by the appropriate Conservation Division District Office. For the purpose of this paragraph, any surface pipeline shall not be considered as a fixed surface facility.
    (B)   For well sites, fencing as a security measure is required when a well is located inside populated limits of a townsite, city or rural residential subdivision, where conditions cause the well to be exposed to the public.
    (C)   In other areas the Commission considers to be a danger, the Commission may establish additional security requirements.
    (D)   The fencing provision will be considered satisfied where the fencing structure is a deterrent to public access.
    (e)   Control and equipment safety; contingency plan.
    (1)   Applicability; radius of exposure. All operations subject to (a) of this Section shall be subject to (2) and (3) of this subsection, if any of the following conditions apply:
    (A)   The 100 ppm radius of exposure is in excess of 50 feet and includes any part of a "public area" or a "public road".
    (B)   The 100 ppm radius of exposure is greater than 3,000 feet.
    (2)   Control and equipment safety provision. Operators subject to this subsection shall install safety devices and maintain them in an operable condition, and/or shall establish written safety procedures designed to prevent the undetected continuing escape of hydrogen sulfide. Safety devices shall be tested annually and a record kept of such tests. All pressure relief safety valves located within the facility shall discharge into a flare system.
    (3)   Contingency plan provision. A contingency plan provision shall be developed for each drilling, producing, well servicing, and plant operation that could reasonably result in accidental exposure of the public to a concentration of hydrogen sulfide in excess of 100 ppm. The operator should make appropriate contacts with any public agency listed in the contingency plan. The contingency plan shall provide an organized plan of action for alerting and protecting the public. The details of a contingency plan are determined largely by the time required for a potentially hazardous concentration of hydrogen sulfide to reach a public area and by the population density in the public area. A copy of the contingency plan should be maintained at the location which lends itself best to activation of the plan. A copy shall be submitted to the appropriate Conservation Division District Office.
    (A)   The plan shall include instructions and procedures for alerting the general public and public safety personnel of the existence of an emergency.
    (B)   The plan shall include procedures for requesting assistance and for follow-up action to remove the public from an area of exposure.
    (C)   The plan shall include a call list which shall include the following as they may be applicable:
    (i)   Local supervisory personnel.
    (ii)   County Sheriff.
    (iii)   Department of Public Safety.
    (iv)   City Police.
    (v)   Ambulance Service.
    (vi)   Hospital.
    (vii)   Fire Department
    (viii)   Contractors for supplemental equipment.
    (ix)   District Commission Office.
    (x)   Local Department of Environmental Quality Office.
    (xi)   Other public agencies.
    (D)   The plan shall include a plat detailing the area of exposure. The plat shall include the locations of private dwellings or residential areas, public facilities, such as schools, business locations, public roads, or other similar areas where the public might reasonably be expected within the area of exposure.
    (E)   The plan shall include provisions for advance briefing of occupied dwellings within the 100 ppm radius of exposure. The following provisions apply:
    (i)   The hazards and characteristics of hydrogen sulfide.
    (ii)   The necessity for an emergency action plan.
    (iii)   Possible sources of hydrogen sulfide within the area of exposure.
    (iv)   Instructions for reporting a gas leak.
    (v)   The method by which the public will be notified of an emergency.
    (vi)   Procedures and/or processes to be implemented in case of an emergency.
    (F)   In a high density population area, or where the population density fluctuates or is difficult to ascertain, a reaction type of plan, in lieu of advance briefing for public notification, will be acceptable. The reaction plan option must be approved by the appropriate Conservation Division District Office.
    (G)   The plan shall include names and telephone numbers of residents within the area of exposure, except in cases where the reaction plan option has been approved by the appropriate Conservation Division District Office.
    (H)   The plan shall include a list of the names and telephone numbers of the responsible parties for each of the possibly occupied public areas, such as schools, churches, businesses, or other public areas or facilities within the area of exposure.
    (f)   Training and requirement provision. Each operator shall provide H2S training in accordance with American National Standards Institute Standard Z390.1-2017 for all of its employees who will be onsite. This training should include:
    (1)   Hazards and characteristics of hydrogen sulfide.
    (2)   Effect on metal components of the system.
    (3)   Operations of safety equipment and life support systems.
    (4)   First aid in event of an employee exposure.
    (5)   Use and operation of H2S monitoring and personal detector equipment.
    (6)   Emergency response procedures to include corrective actions, shut-down procedures, evacuation routes, and rescue methods.
    (g)   Injection of fluids. Injection of fluids containing hydrogen sulfide shall not be allowed under the conditions specified in this Section unless the operator has received prior approval from the Underground Injection Control Department.
    (h)   Venting and flaring.
    (1)   Venting and flaring of gas shall be conducted in accordance with OAC 165:10-3-15. Vent/flare lines or stacks must have properly installed and operating stack arrestors.
    (2)   Flaring equipment in public areas shall be designed and installed so as to resist hydrogen sulfide stress cracking. Existing equipment which is in operation prior to the effective date of this paragraph, and where there has been no failure attributable to hydrogen sulfide stress cracking, shall satisfy the requirements of this paragraph until such time as the equipment experiences a failure. Materials used in any new construction, or modification of or repair to existing equipment subsequent to the effective date of this paragraph shall be selected and manufactured so as to be resistant to hydrogen sulfide stress cracking under the conditions for which the use of such materials is intended.
    (3)   Flare systems shall be designed so as to eliminate restrictions and low points creating differential pressure drops in lines which could cause overpressuring of tank hatches.
    (4)   Flare systems with insufficient pilot fuel gas supply are required to have an alternate fuel gas supply or automated ignition source.
    (5)   The flare tip shall be required to extend a safe distance from the tank as determined in accordance with API Standard 2017 or similar industry practice.
    (i)   Other requirements. In addition to any other requirements of this Section, drilling, production workover operations and processing plant sites where the 100 ppm radius of exposure is 50 feet or greater shall be subject to the following:
    (1)   Protective breathing equipment shall be maintained in a safe operating condition at two or more locations at the site where the occupational exposure limit of gas with a hydrogen sulfide content of 10 ppm or more has been exceeded.
    (2)   Wind direction indicators shall be installed at strategic locations at or near the site and shall be readily visible from all areas of the site and from the entrance to the site.
    (3)   Automatic hydrogen sulfide detection and alarm equipment, including the required detection equipment for each person on the site that will warn of the presence of hydrogen sulfide gas in concentrations of 10 ppm or more shall be utilized at the site.
    (4)   The appropriate Conservation Division District Office shall be notified of the intention to conduct a drill stem test of a formation containing hydrogen sulfide in concentrations of 10 ppm or more to meet the requirements of this Section.
    (j)   Incident and accident notification. Operators shall immediately notify the appropriate Conservation Division District Office or field inspector of any incident involving a release of hydrogen sulfide gas of 100 ppm or more and shall report all hydrogen sulfide related accidents resulting in death or hospitalization of personnel.
    (k)   Exception provision. Any application for exception to the provisions of this Section should specify the provisions to which exception is requested, and set out in written detail the basis on which the exception is to be requested. Written requests for exceptions are to be submitted to the appropriate Conservation Division District Office.
    (l)   Referenced organizations and publications. The following organizations and publications are referenced in this Section:
    (1)   ANSI - American National Standards Institute 1899 L Street, NW, 11th Floor, Washington, DC 20036; Table I, Standard Z390.1-2017.
    (2)   API - American Petroleum Institute 1220 L Street, NW, Washington, DC 20005; API Standard 2017.
    (3)   EPA - U.S. Environmental Protection Agency, Office of Air Quality Planning and Standards, Technical Support Division, Mail Drop C404-03, U.S. EPA, Research Triangle Park, North Carolina 27711.
[Source: Amended at 13 Ok Reg 2395, eff 7-1-96; Amended at 15 Ok Reg 2989, eff 7-15-98; Amended at 24 Ok Reg 1784, eff 7-1-07; Amended at 25 Ok Reg 2187, eff 7-11-08; Amended at 27 Ok Reg 2128, eff 7-11-10; Amended at 33 Ok Reg 593, eff 8-25-16; Amended at 36 Ok Reg 534, eff 8-1-19; Amended at 37 Ok Reg 1121, eff 10-1-20]