HYDROGEN SULFIDE

In the Oilfield

OVERVIEW

General H2S Information

API Guidance BLM Onshore

Order #6 Other Regulations

DOT EPA

WHAT IS HWHAT IS H22SS

Colorless gasColorless gas FlammableFlammable Heavier than airHeavier than air Extremely toxic Extremely toxic ““Rotten egg” smellRotten egg” smell Deadens sense of Deadens sense of

smellsmell

WHY DOES HWHY DOES H22S OCCURS OCCUR

Biological breakdown of organic matter in Biological breakdown of organic matter in an anaerobic environmentan anaerobic environment

HEALTH EFFECTSHEALTH EFFECTS

Low concentrations (<10ppm)– Low concentrations (<10ppm)– irritation of eyes, nose, throat and irritation of eyes, nose, throat and respiratory systemrespiratory system

Moderate concentrations Moderate concentrations (10<x>30ppm)– headache, (10<x>30ppm)– headache, dizziness, nausea, coughing, dizziness, nausea, coughing, vomiting and difficulty breathingvomiting and difficulty breathing

High concentrations (>30ppm)– High concentrations (>30ppm)– shock, convulsions, coma, deathshock, convulsions, coma, death

EXPOSURE LIMITSEXPOSURE LIMITS

ACGIH TLV (8hr)= 10 ppmACGIH TLV (8hr)= 10 ppm OSHA ceiling (15 min)= 20 ppmOSHA ceiling (15 min)= 20 ppm OSHA peak (instantaneous) = 50 OSHA peak (instantaneous) = 50

ppmppm IDLH = 100 ppmIDLH = 100 ppm ATSDR MRL = 0.07 ppm (acute), 0.03 ATSDR MRL = 0.07 ppm (acute), 0.03

ppm (intermediate)ppm (intermediate)

OTHER PHYSICAL PROPERTIESOTHER PHYSICAL PROPERTIES

ExplosiveExplosive Reacts with water to form Sulfuric AcidReacts with water to form Sulfuric Acid

– TearsTears– LungsLungs

Reacts with iron/steel to form Iron Sulfide Reacts with iron/steel to form Iron Sulfide (extremely flammable)(extremely flammable)– Iron spongeIron sponge

Burns to form Sulfur Dioxide (toxic gas)Burns to form Sulfur Dioxide (toxic gas) May lead to metal fatigueMay lead to metal fatigue

HH22S PRODUCTIONS PRODUCTION

AMERICAN PETROLEUM INSTITUTE Recommended Practice 49 -Recommended Practice

for Drilling and Well Servicing operations Involving Hydrogen Sulfide Applies to well drilling, completion, servicing, workover,

downhole maintenance and plug & abandonment procedures.

Establishes location classifications Addresses personnel training, monitoring equipment,

personal protective equipment, contingency planning and emergency procedures.

Also establishes Sulfur Dioxide requirements

LOCATION CLASSIFICATIONS No Hazard Area Condition 1 Area – low hazard

<10 ppm Condition 2 Area – medium hazard

>10ppm, <30 ppm Condition 3 Area – high hazard

>30 ppm

WARNING SYSTEMS Condition 1 Area –

warning sign with green flag or light

Condition 2 Area - warning sign with yellow flag or light; visual and audio alarms

Condition 3 Area – warning sign with red flag or light; visual and audio alarms

MONITORING Equipment

Manufacturer certified for H2S and SO2

Accurate in a range from well below to well above action levels (H2S = 10 ppm, SO2 = 2 ppm)

Mixture of fixed and portable monitors as needed to protect workers

MONITORING EQUIPMENT Used during all activities where a potential of H2S

and SO2 to exceed action levels exists. Located in the following areas:

Bell nipple Mud return line or shale shaker Pipe-trip tank Driller’s station Living quarters Other areas of potential accumulation

Calibrated and functionally tested per manufacturer

WARNING SYSTEM ACTIVATION Typical 2 level alarm

10 ppm 20 to 300 ppm

TRAINING All personnel working in an area with potential of

H2S and SO2 to exceed action levels exists. Minimum topics;

Hazards, characteristics and exposure symptoms Sources Detection equipment, warning signs and wind direction

awareness Workplace procedures, location of safety equipment and

location of safe breathing areas PPE Emergency response

CONTINGENCY PLAN May be required by certain federal, state or local

agencies. Must contain:

Facility specific description and maps Monitoring equipment locations Safety equipment locations Safe breathing area locations Evacuation routes

Training and drill requirements Emergency response procedures

BUREAU OF LAND BUREAU OF LAND MANAGEMENTMANAGEMENT

Onshore Oil and Gas Order No. 6, Onshore Oil and Gas Order No. 6, Hydrogen Sulfide OperationsHydrogen Sulfide Operations

APPLICABILITYAPPLICABILITY

All onshore Federal and Indian oil and All onshore Federal and Indian oil and gas leases.gas leases.

Drilling, completing, testing, reworking, Drilling, completing, testing, reworking, producing, injecting, gathering, storing, producing, injecting, gathering, storing, or treating operations.or treating operations.

Involving zones which are known or Involving zones which are known or could reasonably be expected to could reasonably be expected to contain Hcontain H22S present in concentrations S present in concentrations equal to or greater than 100 ppm.equal to or greater than 100 ppm.

REQUIREMENTSREQUIREMENTS

Written HWritten H22S Drilling Operations Plan S Drilling Operations Plan submitted with APDsubmitted with APD

Written Public Protection Plan submitted Written Public Protection Plan submitted with APD, notification of production or with APD, notification of production or when radius of exposure criteria are metwhen radius of exposure criteria are met

Training Program available for review Training Program available for review upon requestupon request

All plans and programs available at siteAll plans and programs available at site

REQUIREMENTSREQUIREMENTS

HH22S Drilling Operations PlanS Drilling Operations Plan– Site diagrams showing all safety Site diagrams showing all safety

equipment, topography, exit roads, briefing equipment, topography, exit roads, briefing (safe breathing) areas, flare lines and pits(safe breathing) areas, flare lines and pits

– Appropriate well control equipment, Appropriate well control equipment, personal protective equipment, Hpersonal protective equipment, H22S S monitoring equipment, visual and audio monitoring equipment, visual and audio warning system, appropriate mud system, warning system, appropriate mud system, appropriate metallurgical plan and means appropriate metallurgical plan and means of communication from wellsiteof communication from wellsite

REQUIREMENTSREQUIREMENTS

Public Protection PlanPublic Protection Plan– Drilling or production site where:Drilling or production site where:

The 100 ppm radius of exposure is The 100 ppm radius of exposure is greater than 50 feet and includes any greater than 50 feet and includes any occupied residence, scholl, church, occupied residence, scholl, church, park, school bus stop, place of business park, school bus stop, place of business or other are where the public could be or other are where the public could be reasonably expected to frequentreasonably expected to frequent

REQUIREMENTSREQUIREMENTS

Public Protection PlanPublic Protection Plan– Drilling or production site where:Drilling or production site where:

The 500 ppm radius of exposure is The 500 ppm radius of exposure is greater than 50 feet and includes any greater than 50 feet and includes any part of a federal, state, county or part of a federal, state, county or municipal road maintained for public municipal road maintained for public useuse

REQUIREMENTSREQUIREMENTS

Public Protection PlanPublic Protection Plan– Drilling or production site where:Drilling or production site where:

The 100 ppm radius of exposure is The 100 ppm radius of exposure is equal to or greater than 3,000 feet and equal to or greater than 3,000 feet and includes any facility or part of a federal, includes any facility or part of a federal, state, county or municipal road state, county or municipal road maintained for public use.maintained for public use.

RADIUS OF EXPOSURERADIUS OF EXPOSURE

Pasquill-Gifford derrived equation:Pasquill-Gifford derrived equation:X = [1.589)(HX = [1.589)(H22S concentration)(Q)]S concentration)(Q)]0.62580.6258

X = radius of exposureX = radius of exposure

HH22S concentration = decimal equivalent of the S concentration = decimal equivalent of the volume fraction of Hvolume fraction of H22S in the gas streamS in the gas stream

Q = maximum volume of gas determined to Q = maximum volume of gas determined to be available for escape in cubic feet per daybe available for escape in cubic feet per day

ESCAPE RATE (Q)ESCAPE RATE (Q)

Gas production facility = maximum Gas production facility = maximum daily absolute open flow gas daily absolute open flow gas production rateproduction rate

Oil production facility = (gas/oil ratio of Oil production facility = (gas/oil ratio of production) (maximum daily production) (maximum daily production rate)production rate)

Exploration well = use the above from Exploration well = use the above from producing wells from the target producing wells from the target interval in the areainterval in the area

PUBLIC PROTECTION PUBLIC PROTECTION PLANPLAN Must include: Must include:

– responsibilities of key personnel and responsibilities of key personnel and institutions for alerting the public and institutions for alerting the public and requesting assistance; requesting assistance;

– list of telephone numbers and names of list of telephone numbers and names of response agencies or contractors, response agencies or contractors, residents, those responsible for occupants residents, those responsible for occupants of public buildings and those responsible of public buildings and those responsible for safety of public roadways; for safety of public roadways;

– a plat of the 100 ppm and 500 ppm radius a plat of the 100 ppm and 500 ppm radius of exposure showing all private and public of exposure showing all private and public buildings and roads; buildings and roads;

– emergency response measuresemergency response measures

PUBLIC PROTECTION PUBLIC PROTECTION PLANPLAN May be required May be required

to include: public to include: public education education seminars, mass seminars, mass alert systems alert systems (including (including telephone, telephone, commercial radio commercial radio or television), and or television), and public input public input allowancesallowances

OTHER REGULATIONSOTHER REGULATIONS

OSHAOSHA Process Safety Management Process Safety Management

DOTDOT Pipeline Safety RequirementsPipeline Safety Requirements

EPAEPA Risk Management Plan requirementsRisk Management Plan requirements SARA Title 3 requirementsSARA Title 3 requirements

STATE SPECIFICSTATE SPECIFIC