26 MAC Pt. 2, Ch. 1, R. 1.66
OPERATIONS INVOLVING HYDROGEN SULFIDE
Cite as 26 Miss. Admin. Code Pt. 2, Ch. 1, R. 1.66
OPERATIONS INVOLVING HYDROGEN SULFIDE. Preventative measures
shall be taken to control the effects of hydrogen sulfide (H2S) at all operations where H2S
concentrations in the gas stream are equal to 100 ppm or more. Such operations shall include,
but may not be limited to drilling, working over, testing, producing, gathering, metering,
processing, storing, transporting, and injecting.
(1) Definitions.
In addition to the definitions set forth in State Oil and Gas Board Order No. 201-51, Rule 2,
unless the context otherwise requires, the following words shall have the meanings indicated
when used within this rule.
(a) Radius of exposure: That radius constructed with the point of escape as its
starting point and its length calculated as provided for in Paragraph (10)(b).
(b) Area of exposure: The area within a circle constructed with the point of escape as
its center and the radius of exposure as its radius.
(c) Public area: Shall include but not be limited to a dwelling, place of 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 expect
to be populated.
(d) Public road: Any federal, state, county, or municipal street or road owned or
maintained for public access or use.
(e) Sulfide stress cracking: The cracking phenomenon which is the result of corrosive
action of hydrogen sulfide on susceptible metals under stress.
(f) Facility modification: Any change in the operation, such as an increase in
throughput, in excess of the currently permitted capacity; or any change that
would increase the radius of exposure.
(g) Public infringement: A public area and/or a public road has been established
within an area of exposure to the degree that such infringement would change the
applicable requirements of this rule to those operations responsible for creating
the area of exposure.
(h) Contingency plan: A written document that shall provide an organized plan of
action for alerting and protecting the public within an area of exposure following
the accidental release of a potentially hazardous volume of hydrogen sulfide.
(i) Civil authorities shall include but not be limited to the following agencies:
Governor, Assistant to Governor, local Government Emergency Management/Civil Defense
agency, Mississippi Adjutant General, Mississippi National Guard, Mississippi Emergency
Management Agency, Bureau of Pollution Control, Red Cross, Mississippi State Department of
Health, Department of Public Safety, and such other agencies as in the discretion of the
Supervisor of Oil and Gas deems advisable.
(2) Operator Responsibility.
(a) It shall be the responsibility of each operator to conduct operations in accordance
with Paragraph (3) through (8) below. Paragraph (9) requires each operator to file a Certificate
Of Compliance For Hydrogen Sulfide Operations (Certificate) for each operation that handles or
could reasonably be expected to encounter sour oil and/or gas.
(b) Exemptions to Paragraph (3) through (8) may be obtained by filing a Certificate
with the Supervisor as directed under Paragraph (10) below.
(c) Variances to or waivers from the specifications of this rule may be granted by the
Supervisor upon showing a good cause by the operator.
(3) Safety Program.
A safety program shall be established and maintained to promote safety procedures. All
personnel that are assigned, contracted, or employed shall be instructed as to hazards of H2S,
including physiological responses and the application of first aid to victims of H2S exposure.
(4) Equipment and Materials.
All equipment and materials that will be exposed, or can reasonably be expected to be
exposed to H2S, shall be designed and maintained in accordance with specifications evolved
through technology of the latest state-of-the-art to resist damage caused by hydrogen sulfide
stress cracking, embrittlement, or corrosion.
(5) Warning Systems.
(a) Warning signs.
1. For above-ground and fixed surface facilities, the operator shall post, where
permitted by law, clearly visible warning signs on public streets or roads which provide direct
access to facilities.
2. On offshore facilities, the operator shall display clearly visible warning signs
on at least two sides of the rig and at points of access to the rig or platform.
3. In populated areas such as townsites and cities where the use of signs is not
considered to be acceptable, an alternate warning plan may be approved upon written request to
the Supervisor.
(b) Monitors and Alarms.
1. Unless otherwise approved by the Supervisor, each drilling, workover, test, or
plant facility shall have an H2S monitoring system which activates visible alarms when the
concentration of H2S exceeds 10 parts per million (ppm) in air and audible alarms when the
concentration of H2S exceeds 20 parts per million (ppm) in the air. This system shall be capable
of sensing a minimum of 5 ppm in the air.
(i) As a minimum, H2S sensors for onshore drilling and workover rigs shall
be located at the rig floor, bell nipple, shale shaker, and mud pits; for offshore drilling and
workover rigs, the sensors shall be located at the rig floor, bell nipple, shale shaker, mud pits,
and living quarters.
(ii) For drilling operations, this monitor and alarm system shall be on site and
operational prior to penetrating the H2S bearing zone in accordance with the time specified in the
contingency plan and approved by the Supervisor. Said equipment shall be on site and
operational prior to commencing all other operations involving H2S.
2. As approved by the Supervisor, the operator of each gathering system,
production well, and injection well shall install and maintain in operable condition safety devices
to include automatic shut-down devices designed to prevent the undetected continuing escape of
hydrogen sulfide.
3. The operator of each unplugged inactive well shall establish safety procedures,
as approved by the Supervisor, which are designed to prevent the undetected continuing escape
of hydrogen sulfide.
(c) Wind Direction Equipment. Wind direction equipment shall be installed at
prominent locations on or near the drilling, workover, test, or plant facility to indicate the wind
direction at all times and the safe upwind areas in the event H2S becomes present in the
atmosphere.
(d) Danger Signals.
1. Danger signals consisting of signs and flags shall be displayed in a manner
visible to all traffic approaching the facility. All signals shall be illuminated under conditions of
limited visibility when in use. If illumination is not feasible, signals must be constructed of
reflective material or covered with reflective paint so they will be readily visible from other light
sources such as automobiles. Danger signals shall be displayed to indicate the following
operational conditions and requirements:
(i) Possible danger - green - When the concentration of H2S
is less than 10 ppm in air;
(ii) Moderate danger - yellow - When the concentration of H2S reaches 10
ppm in air. If the concentration of H2S reaches 20 ppm in air, breathing apparatus shall be worn
by all personnel and all nonessential personnel shall proceed to the safe briefing areas;
(iii) Extreme danger - red - When the concentration of H2S reaches 50 ppm in
air. All nonessential personnel shall be evacuated, immediate notification shall be given to local
civil authorities, and traffic in the immediate vicinity of the facility shall be diverted. The State
Oil and Gas Board and other appropriate governmental agencies shall be notified as soon as
possible when conditions of extreme danger exist.
(6) Training Requirements.
(a) Each operator whose operations are subject to this rule shall provide training of
personnel responsible for his operations. An attendance list of these training sessions shall be
maintained by the operator.
(b) The training of personnel shall include the following elements:
1. Safety precautions;
2. Operation of safety equipment and life support systems;
3. Corrective action and shutdown procedures;
4. Effect on metal components of the system.
(7) Personnel Safety Equipment.
(a) Breathing apparatus shall be provided and be readily accessible. A minimum
requirement shall be to provide self-contained breathing equipment for all personnel that could
be exposed to H2S concentrations in excess of 10 parts per million (ppm) in air.
(b) Where H2S concentrations reach 20 ppm in air, a system of breathing air
manifolds, hoses, and masks shall be provided. A rechargeable cascade air bottle system shall be
provided to refill individual bottles of breathing air. Additional equipment such as a first aid kit,
nose cups, ear plugs, spectacle kits, portable H2S detectors, retrieval ropes and harnesses, chalk
boards, note pads, bull horns, flashing lights, resuscitators, and a litter shall also be available.
(c) For drilling operations, the equipment specified in Paragraphs (7)(a) and (7)(b)
shall be on site and operational prior to penetrating the H2S bearing zone in accordance with the
time specified in the contingency plan and approved by the Supervisor. Said equipment shall be
on site and operational prior to commencing all other operations involving H2S.
(d) Explosion-proof ventilation devices shall be provided in critical work areas of the
drilling, workover, test, or plant facility and be multidirectional and capable of dispersing H2S
vapors.
(e) If H2S is detected, frequent inspections of all areas of poor ventilation shall be
made with an H2S detector instrument, and personal H2S detectors shall be made available to
personnel.
(8) Contingency Plan.
(a) Operations that handle gas containing 100 ppm H2S or more in the gas stream
must formulate a contingency plan unless exempted under Paragraph (10). Unless otherwise
approved, a contingency plan should be filed (in triplicate) with the Supervisor within 30 days of
the approval of the drilling permit application.
The contingency plan must be approved by the Supervisor prior to commencing the
following operations;
1. Penetrating the H2S bearing zone during drilling operations.
2. Working over or recompleting a well in an H2S bearing zone;
3. Testing or putting on permanent production a well that is completed in an H2S
bearing zone;
4. Producing hydrocarbons bearing H2S into a pipeline or gathering system;
5. Starting up a plant or facility that will remove H2S from production;
6. Implementing any modification to an existing operation or facility which
increases the radius of exposure in a public area or results in a change of the
applicable requirements of this rule.
.
(b) A contingency plan shall include a plat or aerial photograph covering the area
of exposure or an area having a radius of one mile, whichever is greater. The plat shall include
the location of the well, plant, or corridor showing all good roads, residences, public areas and
places, areas of low elevation where H2S might accumulate, the direction of prevailing winds, oil
and gas wells, separators, heaters, corridors of gathering or pipeline systems, pumping stations,
plants, refineries, transformer stations, and other manmade structures or features that may be of
importance. An index list of houses and places of business with telephone numbers and names
and numbers of residents and employees as well as the identification of residents needing
assistance in evacuation shall accompany the plan. This index list shall be limited to those
houses and places of business located within a radius of one mile. The radius about the well,
plant, or corridor may be extended beyond one mile if deemed necessary by the operator, or at
the request of the Supervisor. The plan shall also include:
1. Information about the safety program established in Paragraph (3), the training
requirements in Paragraph (6), the personnel safety equipment required in Paragraph (7), the
location of briefing areas, and responsibilities of personnel during different operational
conditions;
2. A description of the warning systems required in Paragraph (5) to include
number, location, and detection limits of all monitors as well as the schedules for calibrating and
testing said systems;
3. For drilling operations, a specification of the time at which the warning
systems required in Paragraph (5) and the personnel safety equipment required in Paragraph (7)
will be on site and operational;
4. Procedures to evacuate residences, businesses, and public places;
5. Procedures to divert traffic in the immediate vicinity and to notify the local
civil authorities, the State Oil and Gas Board, and other appropriate governmental agencies;
6. Procedures to evacuate non-essential personnel from the well and/or facility in
the event attempts to control the well and/or facility are unsuccessful;
7. A list including names, addresses, and telephone numbers of the closest
hospitals, ambulance services, medical personnel, and other individuals or facilities that could
assist in the event of an emergency;
8. The name, address, and telephone number of the individual in charge of
administering the plan;
9. Any other information that the operator deems appropriate;
10. Other information deemed necessary by the Supervisor.
(c) A new or amended contingency plan shall be filed with the Supervisor when any
significant change in public exposure caused by public infringement of an existing radius of
exposure requires such changes to be made. Otherwise, the contingency plan for each facility
shall be reviewed and updated on an annual basis. Any updates, revisions, and/or amendments to
a contingency plan shall be submitted to the Supervisor within 30 days of the plan's anniversary
date or within 30 days of the date an operator becomes aware of the public infringement, as
applicable. If there are no changes, an annual statement of review shall be filed with the
Supervisor.
(d) The filing requirement may be waived if a current plan has previously been
submitted and is in compliance with the requirements set forth herein. Plans filed prior to the
effective date of this rule must be reviewed and modified, if necessary, to obtain compliance
with this Paragraph within 180 days of said effective date.
(e) Unless previously provided, copies of the approved contingency plan shall be
provided to local civil authorities prior to commencing any one of the operations set forth in
Paragraph (8)(a) and be readily available at the drilling, workover, test, or plant facility.
(9) Certificate Of Compliance For Hydrogen Sulfide Operations.
(a) A Certificate shall be filed in triplicate with the Supervisor for each facility or
operation subject to any requirement of this rule.
(b) The Certificate shall certify that the operator has complied, or will comply, with
the applicable requirements of this rule.
(c) For drilling operations, the Certificate shall be filed with the Supervisor as a part
of the application to drill. For facilities involving other types of H2S operation, as set forth in
Paragraph (8)(a), the Certificate shall be filed with and approval granted by the Supervisor prior
to commencing those operations.
(d) A Certificate shall be filed for existing facilities or operations within 180 days of
the effective date of this rule.
(e) A new or amended Certificate shall be required if there is a change in public
exposure caused by public infringement of an existing radius of exposure resulting in a change in
the applicable provisions of this rule, not described by the existing Certificate. The operator
shall file the new or amended certificate within 30 days after an operator becomes aware of such
infringement.
(f) A new or amended Certificate shall be required if there is a modification of an
existing operation or facility which increases the radius of exposure in a public area or results in
a change in the applicable provisions of this rule not described by the existing Certificate. The
operator shall file the new or amended Certificate at least 10 days prior to initiating the operation
or construction. Approval of the Certificate must be granted by the Supervisor prior to
commencing that operation or construction.
(g) Each facility or operation for which a Certificate has been approved shall be
recertified by the operator on an annual basis. The recertification shall be filed with the
Supervisor within 30 days of the anniversary date of the most recently approved Certificate for
that facility or operation.
(10) Rule Exemptions. Exemptions from Paragraphs (3) through (8) may be obtained by
filing the Certificate as directed below:
(a) Each operator must determine the hydrogen sulfide concentration in the gaseous
mixture in an operation or system.
1. Tests shall be made in accordance with standards as set by American Society
for Testing and Methods (ASTM) Standard D-2385-66, or Gas Processors Association (GPA)
Plant Operation Test Manual C-1, GPA Publication 2265-68, as revised, or other methods
approved by the Supervisor.
2. Tests of vapor accumulation in storage tanks may be made with National
Institute of Occupational Safety and Health (NIOSH) approved colormetric tubes.
(b) To obtain an exemption from this rule, the radius of exposure must be
determined, except in the cases of storage tanks, using the following Pasquill-Gifford equation,
or by other methods satisfactory to the Supervisor:
For determining the radius of exposure:
X={(1.589) (mole fraction H2S) (Q)} (.6258) Where: X=radius of exposure in feet for 100
ppm H2S concentration
Q = maximum volume determined to be available for escape in standard cubic feet per
day
H2S = mole fraction of hydrogen sulfide in the gaseous mixture available for escape (i.e.
for 1% H2S (volume basis), mole fraction is .01)
(c) The volume used as the escape rate in determining the radius of exposure shall be
that specified below, as applicable:
1. The maximum daily volume rate of gas containing hydrogen sulfide handled
by that system for which the radius of exposure is calculated.
2. For existing gas wells, the estimated maximum open flow potential shall be
used.
3. For new wells drilled in developed areas, the escape rate shall be determined
by using the estimated maximum flow potential of adjacent wells in the field.
4. The escape rate used in determining the radius of exposure shall be corrected
to standard conditions of 15.025 psia and 60oF.
(d) For drilling of a well in an area where insufficient data exist to calculate a radius
of exposure but where hydrogen sulfide may be expected, then a radius of exposure equal to
one-half mile shall be assumed. A lesser-assumed radius may be considered upon written
request setting out the justification for same.
(e) Storage tanks which are utilized as part of a production operation and which are
operated at or near atmospheric pressure are exempt from Paragraphs (3) and (5) through (8);
however, where the vapor accumulation has a hydrogen sulfide concentration in excess of 500
ppm, the storage tanks shall be subject to the following:
1. Storage tanks are exempt from Paragraphs (5), 7b,c,d, and e), and (8) only;
2. A warning sign shall be posted on or within 50 feet of the facility to alert the
general public of the potential danger;
3. Fencing, as a security measure, is required when storage tanks are located
inside the limits of a townsite or city or where conditions cause the storage
tanks to be exposed to the public.
(f) Operations with a radius of exposure less than 50 feet are exempt from
Paragraphs (3) through (8) upon filing the Certificate.
(g) Provided no public area is included, operations with a radius of exposure greater
than 50 feet and less than one-half mile are exempt from Paragraphs (5)(b) through (8) upon
filing the Certificate.
(h) Operations with a radius of exposure that either is greater than 50 feet and
includes a public area or is equal to or greater than one-half mile are not eligible for an
exemption under this Paragraph.