Current through Register Vol. 47, No. 17, September 10, 2024
a.
General.
(1) Operators will avoid
any uncontrolled release or hazardous accumulation of hydrogen sulfide ("H2S")
gas. If releases or hazardous accumulations of H2S cannot be avoided, or during
upset conditions or malfunctions, Operators will employ mitigation measures to
reduce potential harms to safety.
(2)
Scope. To protect and
minimize adverse impacts to public health, safety, welfare, the environment,
and wildlife resources, Operators will comply with this Rule 612 where oil and
gas exploration and production occurs in areas known or reasonably expected to
contain H2S.
b.
Radius of Exposure
Calculation. When an Operator is conducting drilling, workover,
completion, or production operations in a geologic zone where the Operator
knows or reasonably expects to encounter, or a laboratory gas analysis detects,
H2S in the gas stream at concentrations at or above 100 parts per million
("ppm"), the Operator will calculate the radius of exposure to any Building
Unit, High Occupancy Building Unit, or Designated Outside Activity Area.
(1) Radius of exposure will be calculated
pursuant to Bureau of Land Management ("BLM") Onshore Order No. 6 (Jan. 22,
1991). Only the 1991 version of Onshore Order 6 applies to this Rule; later
amendments do not apply. All materials incorporated by reference in this Rule
are available for public inspection during normal business hours from the
Public Room Administrator at the office of the Commission, 1120 Lincoln Street,
Suite 801, Denver, CO 80203. In addition, these materials are available from
the BLM Colorado State Office, 2850 Youngfield St., Lakewood, CO 80215, and are
available online at
https://www.blm.gov/sites/blm.gov/files/energy_onshoreorder6.pdf.
(2) If insufficient data exists to calculate
a radius of exposure, the Operator will assume the radius of exposure is 3,000
feet.
(3) Operators will perform
gas stream laboratory analysis if any concentration of H2S of 20 ppm or greater
is detected by using field measurement devices during drilling, completion, or
production operations. Operators will report any gas stream laboratory analysis
greater than 1 ppm H2S to the Director and the Relevant and Proximate Local
Government(s). If the Operator ever detects H2S concentrations greater than 1
ppm, the Operator will repeat gas stream laboratory analysis
annually.
c.
H2S Public Protection Plan. A public
protection plan is required if:
(1) The 100
ppm radius of exposure is greater than 50 feet and there is a Building Unit,
High Occupancy Building Unit, or Designated Outside Activity Area within the
radius of exposure;
(2) The 100 ppm
radius of exposure is equal to or greater than 3,000 feet and includes any
publicly-maintained road; or
(3)
The Director determines that a public protection plan is necessary to protect
and minimize adverse impacts to public health, safety, welfare, the
environment, or wildlife resources.
d.
H2S Drilling
Operations Plan.
(1) When proposing to
drill a Well in areas where H2S gas can reasonably be expected to be
encountered, Operators will submit a H2S drilling operations plan with their
Form 2, unless the plan was already submitted with their Form 2A, pursuant to
Rule 304.c.(10).
(2) Operators will
prepare the H2S drilling operations plan pursuant to BLM Onshore Order No. 6,
as incorporated by reference in Rule 612.b.(1).
e.
Designated H2S Locations. If
an Operator ever measures H2S gas stream concentrations of 100 ppm or greater
at a Well, the Well is a designated H2S location. All designated H2S locations
will be designed and operated in accordance with BLM Onshore Order No. 6, as
incorporated by reference in Rule 612.b.(1). Designated H2S locations will
have:
(1) Signs indicating the presence of H2S
not less than 200 feet or more than 500 feet from the entrance of the
location;
(2)
H2S monitoring with audible and visible alarms at 10 ppm
of H2S;
(3)
At least one wind indicator; and
(4) With landowner approval, adequate
fencing.
f.
Operations in Designated H2S Locations.
(1) In a designated H2S location, Operators
will employ a secondary means of immediate Well control at all Wells that are
known to have H2S through use of a christmas tree or downhole completion
equipment. The equipment will allow downhole accessibility (reentry) under
pressure for permanent Well control. When the presence of H2S is detected
during drilling in formations not tested, completed, or produced, the Operator
will report depth intervals, concentrations measured at surface or within
drilling Fluid, and the control measures used.
(2) At Oil and Gas Locations producing gas
with greater than 100 ppm H2S, Operators will monitor all storage Tanks. Any
headspace field measurement or laboratory analysis greater than 500 ppm H2S, or
10 ppm H2S in ambient air, will require mitigation measures to control and
minimize accumulation within the storage Tank.
(3) All operations at an Oil and Gas Location
with potential H2S concentrations greater than 100 ppm will:
A. Use equipment that can withstand the
effects and stress of H2S;
B. Be
conducted pursuant to American National Standards Institute ("ANSI")/National
Association of Corrosion Engineers ("NACE") Standard MR0175/ISO 15156-2015-SG,
Petroleum and natural gas industries - Materials for use in H2S-containing
environments in oil and gas production (2015), or some other Director approved
standard for selection of metallic equipment. Only the 2015 version of
ANSI/NACE Standard MR0175/ISO 15156-2015-SG applies to this Rule; later
amendments do not apply. All material incorporated by reference in this Rule
are available for public inspection during normal business hours from the
Public Room Administrator at the office of the Commission, 1120 Lincoln Street,
Suite 801, Denver, CO 80203. In addition, these materials are available from
NACE International, 15835 Park Ten Pl, Houston, TX 77084; and
C. If applicable, use adequate protection by
chemical inhibition or such other methods that control or limit H2S's corrosive
effects.
(4) Operators
in designated H2S locations will conduct a laboratory analysis of the gas
stream for H2S at least monthly. If the H2S concentration increases by greater
than 25%, the Operator will recalculate the radius of exposure and notify the
Director and the Relevant and Proximate Local Government(s).
g.
Operator Reports of
H2S.
(1)
Operators will report on a Form 42, Field Operations Notice - Notice of H2S on
an Oil and Gas Location any laboratory analysis indicating the presence of H2S
gas to the Director within 48 hours. Upon receipt of the Form 42, the Director
will notify the Relevant and Proximate Local Government(s).
(2) If a laboratory analysis indicates any
concentrations of H2S gas greater than 100 ppm in the gas stream, or headspace
field measurement or laboratory analysis greater than 500 ppm
H2S, or 10 ppm H2S in ambient air, the Operator will
report such findings to the Director on a Form 4, including the information
required in Rules 612.b-d, as applicable, within 45 days.
h. Unless deemed an immediate operational
need for safety reasons and the release does not pose a risk to public safety,
Operators may only intentionally release H2S gas with prior Director approval
of a Form 4. The Form 4 will include a proposed air monitoring plan for H2S. If
combustion or Flaring is proposed, the air monitoring plan will include a SO2
by-product detection plan.
i. If an
intentional release of H2S gas occurs due to Upset Conditions or malfunctions,
the Operator will notify the Director, the Relevant and Proximate Local
Government(s), and the local emergency response agency orally within 24 hours,
followed by the filing of a Form 4 within 5 days.
j. All H2S monitoring,
mitigation, and safety equipment will be maintained and functioning in good
working order at all times.
k.
Temporary Abandonment of a H2S Well.
(1)
Prior to temporarily abandoning a Well with potential concentrations of greater
than 100 ppm H2S in its gas stream, the Operator will
file a Form 4, Notice of Temporarily Abandoned Status to obtain the Director's
approval.
(2) Operators will
install a cast iron bridge plug and maintain H2S monitoring and telemetry
equipment when temporarily abandoning a Well with potential concentrations of
greater than 100 ppm H2S in its gas stream.
