Current through September 21, 2024
(a) The following
shall apply to the drilling of all wells unless altered, modified, or changed
for a particular well, pool, unit, area or lands upon hearing before the
Commission:
(i) Surface casing shall be run to
reach a depth below all known or reasonably estimated utilizable groundwater
(as defined in Chapter 3, Section 8(c)(iv)) to protect the Use Class category
and to prevent blowouts or uncontrolled flows. Unless otherwise approved by the
Supervisor, surface casing shall be set at a minimum of three (3) joints or
approximately one hundred (100) to one hundred twenty (120) feet below the
depth of any Wyoming Office of State Engineer permitted water supply wells
designated for domestic, stock water, irrigation or municipal use, within a
minimum of one-quarter (1/4) mile radius and shall be cemented to surface. Any
coalbed methane well receiving a Ground Water Appropriate Permit (Form UW 5)
from the State Engineer's Office is exempt from this specific subsection. Fresh
water flows detected during drilling, including seismic, core, or other
exploratory holes, shall be recorded on Form 19 (Report of Fresh Water Flows)
and reported to the Commission on the next business day. Information contained
on the form shall describe the depth at which the sand was encountered, the
thickness, and the rate of water flow, if known. In areas where pressures and
formations are unknown, surface casing shall be of sufficient size to permit
the use of an intermediate string or strings of casing. Surface casing shall be
set in or through an impervious formation and shall be cemented by the pump and
plug or displacement or other approved method with sufficient cement to fill
the annulus to the top of the hole, all in accordance with reasonable
requirements of the Supervisor. The Supervisor may require the Owner or
Operator to pump a specified quantity of excess cement above the design volume
if severe washed out hole conditions are known to exist on the surface hole
portion of wells in the immediate vicinity of the well to be drilled. If cement
is not circulated to the surface during the primary operation, the
Owner/Operator shall perform supplemental cementing operations to assure that
the annular space from the casing shoe to the surface is filled with cement.
The Supervisor may require the Owner or Operator to provide cased hole bond
logs to be run for casing strings to demonstrate isolation from the placement
of cement across and above the productive intervals or above the last casing
shoe in the well, if there is a demonstrated reason to believe an inadequate
cement job was performed.
(ii)
Unless otherwise provided by specific order of the Commission for a particular
well or wells or for a particular pool or parts thereof, cemented casing string
shall stand under pressure until the cement at the shoe has reached a
compressive strength of five hundred pounds per square inch (500 lbs./sq. in.).
In addition, the API free-water separation for all cement slurries used shall
average no more than four (4) milliliters per two hundred fifty (250)
milliliters of cement. All cements used shall achieve a minimum compressive
strength of one hundred (100) psi in twenty-four (24) hours measured at eighty
degrees Fahrenheit (80? F.). Testing for these properties shall be in
accordance with accepted industry standards. The term "under pressure" as used
herein shall be complied with if one float valve is used or if pressure is
otherwise held;
(iii) There shall
be installed and maintained on all wells blowout preventers and related
equipment in accordance with Chapter 3, Section 23(i) of these rules;
(iv) Setting depths of all casing strings
shall be determined by taking into account formation fracture gradients and the
maximum anticipated pressure to be maintained within the wellbore;
(v) If and when it becomes necessary to run a
production string, such string shall be cemented by the pump and plug method
and shall be properly tested by the pressure method before cement plugs are
drilled;
(vi) Natural gas, which
may be encountered in a substantial quantity in any section of cable tool
drilled hole above the ultimate objective, shall be shut off with reasonable
diligence either by mudding, by casing, or other approved method, and confined
to its original source to the satisfaction of the Supervisor. Any gas escaping
from the well during drilling operations shall be, so far as practicable,
conducted to a safe distance from the well site and burned.
(b) Before drilling commences,
approval to construct proper and adequate reserve pits for the reception and
confinement of mud and cuttings and to facilitate the drilling operation shall
be applied for and received in accordance with Chapter 4, Section 1 of these
rules. Special precautions including, but not limited to, an impermeable liner
and/or membrane, monitoring systems, or closed systems, shall be taken, if
necessary, to prevent contamination of streams and potable water and to provide
additional protection to human health and safety in instances where drilling
operations are conducted in close proximity to water supplies. Wells, pits,
wellheads, pumping units, tanks, and treaters shall be located no closer than
three hundred fifty feet (350') from any water supply. The Supervisor may grant
a variance to increase or decrease this distance for good cause.
(c) Before drilling commences, the
Owner/Operator shall notify the Commission of his intent to spud the well and
an approximate time the BOP test will be run.
(d) For each well drilled within the Special
Sodium Drilling Area - A or - B (SSDA - A or - B), as defined in Chapter 1,
Section 2(ww) and (xx) of these rules, a complete proposed casing and cementing
program shall be submitted on the Application for Permit to Drill (Form 1). For
the life of the well each drilling and casing program, unless altered,
modified, or changed for a particular well, pool, unit, area or lands upon
hearing before the Commission, shall be designed to:
(i) Provide suitable and safe operating
conditions for the total measured depth proposed;
(ii) Confine fluids to the
wellbore;
(iii) Prevent migration
of fluids from one stratum to another;
(iv) Assure control of well pressures
encountered;
(v) Prevent
contamination of freshwater;
(vi)
Prevent significant damage to Trona Mineral Resources; and,
(vii) Provide well control until the next
casing is set.
All pertinent factors for well control should be considered,
including formation fracture gradients, formation pressures, casing setting
depths, proposed total depth, and projected mining.
(e) In addition, the following requirements
apply to all wells drilled within the Special Sodium Drilling Area - A (SSDA -
A), as defined in Chapter 1, Section 2(ww) of these rules, unless altered,
modified, or changed for a particular well, pool, unit, area or lands upon
hearing before the Commission:
(i) Any oil or
gas wells that will be drilled within the area of influence of underground
trona mining shall be:
(A) Designed and
installed to withstand the forces and potentially damaging influences from
mining as certified by a Registered Professional Engineer registered in the
state of Wyoming or
(B)
Demonstrated to be located outside the mining influence area. Mining influence
includes surface subsidence and underground formation collapse, faulting
fracturing and related stresses that may provide avenues for communication with
active or inactive underground mine works, open mine voids, and corrosive mine
fluids that may cause well casing corrosion or failure as a result of
mining.
(ii) Conductor
casing must be set to a depth of at least forty feet (40') or into a competent
stratum, whichever is greater. The casing must be cemented with a quantity of
cement to fill the annular space up to the surface and topped off if not at the
surface. Cement fill must be verified by observation of cement
returns.
(iii) Centralized surface
casing shall be set below the Trona Interval from the surface. Centralizers
shall be spaced to ensure enough casing annulus is maintained on all sides of
the casing to allow cement fill space throughout the cased interval. The casing
shall be set into a competent stratum and cemented with sufficient cement in
the annulus to circulate to the surface. If cement does not circulate to the
surface, the open annulus must be cemented to the surface before drilling
ahead. A cement bond log or cement evaluation tool must be run to verify
adequate cement around surface casing. Remedial cementing may be required if it
is determined that insufficient bonding occurred.
(iv) Prior to well completion, a directional
survey shall be run from the base of the Trona Interval to surface to verify
wellbore location relative to surface location. Results of the survey shall be
submitted to the Supervisor pursuant to Chapter 3, Section 21 of these
rules.
(v) Intermediate and/or
production casings, if required to be cemented, shall be cemented with a
sufficient quantity of cement to provide annular fill up from the surface
casing shoe to two hundred feet (200') above the Trona Interval. All casing
annuluses reaching the production zones shall be cemented for two hundred feet
(200') or more above the highest producing zone. All casings shall be
centralized throughout their cemented annulus intervals. Before drilling ahead,
all casings shall be tested in accordance with subsection (e)(vii) of this
section.
(vi) Liners may be set and
cemented as an extension of casings provided that the cemented liner has a
minimum of two hundred feet (200') of cemented lap within the next larger
casing. Before drilling ahead, a cemented liner and lap must test in accordance
with subsection (e)(vii) of this section, to determine that a seal between the
liner top and next larger casing has been achieved.
(vii) Before drilling out the liner after
cementing, all casing, liners, and liner laps must be tested to a surface
pressure of one thousand five hundred (1,500) psig, or 0.25 psi/ft multiplied
by the true vertical depth of the casing shoe, whichever is greater; however,
surface pressure must not subject the casing to a hoop stress that will exceed
seventy percent (70%) of the minimum yield strength of the casing. Sufficient
notice of pressure test must be given, so that a representative of the
Commission may witness the test. A cement bond log or other appropriate log
shall be obtained to evaluate cement integrity in each cemented zone for each
cemented casing annulus and the results submitted to the Supervisor for
approval, pursuant to Chapter 3, Section 21 of these rules. If there are
indications of improper cementing, or the pressure declines more than ten
percent (10%) in 30 minutes, corrective measures shall be taken.
(viii) Casing annuluses not cemented through
the Trona Interval that extend to the surface shall be continually monitored
for leaks by equipping the surface termination with a rupture disk (fail open)
pressure relief valve with tattle-tale (or similar device) to detect, alarm,
and relieve excess annular pressure buildup. The device shall be set to fail
open at one hundred (100) psi. Blocking of this pressure relief valve in an
open position shall be prohibited. In the event the monitored casing pressure
exceeds one hundred (100) psi, the Supervisor and the trona producers holding
valid Wyoming DEQ permits to mine trona shall be notified as soon as possible
and remedial actions shall be implemented with the Supervisor's approval. The
pressure relief device shall be tested every two (2) years to insure it is
functioning properly. Tattle-tale monitoring units that cease to monitor or
communicate shall be promptly repaired. Pressure devices shall be repaired or
replaced immediately upon failing a pressure test or following a
rupture.
(ix) If a well has not
been tested for mechanical integrity within five (5) years and is shut-in for
an extended period the casing strings capable of being tested shall be
evaluated for mechanical integrity during the shut-in period.
(x) Cathodic protection or other equivalent
corrosion prevention shall be applied to all casing strings.
(f) Within the Special Sodium
Drilling Area - A or - B, as defined in Chapter 1, Section 2(ww) or (xx) of
these rules, or all wells defined in Chapter 1, Section 2 of these rules unless
altered, modified, or changed upon hearing before the Commission, or shown to
contain no Trona Mineral Resources, shall only use stimulation methods that do
not significantly damage the Trona Mineral Resources. A plan of work for any
stimulation operation shall be submitted to the Supervisor and approved before
the work is undertaken.
(i) Well stimulation
operations within the Trona Interval shall include a post stimulation survey
that identifies the extent of induced fractures. Results of the survey shall be
submitted to the Supervisor for evaluation to determine if induced fractures
have significantly intersected the Trona Mineral Resources and if corrective
action is required.
(ii)
Stimulation fluids shall be designed to prevent significant dissolution to the
Trona Mineral Resources. The Supervisor shall require corrective action if it
is determined that significant damage to the Trona Mineral Resources has, or is
likely to occur.
(g)
Within the boundaries of the Special Sodium Drilling Area - A or - B, as
defined in Chapter 1, Section 2(ww) or (xx) of these rules, all wells defined
in Chapter 1, Section 2 of these rules unless altered, modified, or changed
upon hearing before the Commission, shall use drilling fluids that will not
significantly dissolve the Trona Mineral Resource.
