35 Ill. Adm. Code 730.187
Logging, Sampling, and Testing Prior to Injection Well Operation
Section 730.187 Logging, Sampling, and Testing Prior to
Injection Well Operation
a) During
the drilling and construction of a Class VI injection well, the owner or
operator must run appropriate logs, surveys and tests to determine or verify
the depth, thickness, porosity, permeability and lithology of all relevant
geologic formations and the salinity of any formation fluids in those
formations, to ensure conformance with the injection well construction
requirements under Section 730.186 and to establish accurate baseline data
against which future measurements may be compared. The owner or operator must
submit to the Agency a descriptive report prepared by a knowledgeable log
analyst that includes an interpretation of the results of the logs and tests.
At a minimum, these logs and tests must include the following information
items:
1) Deviation
checks made during drilling on all holes constructed by drilling a pilot hole
that is enlarged by reaming or another method. These checks must be at
sufficiently frequent intervals to determine the location of the borehole and
to ensure that vertical avenues for fluid movement in the form of diverging
holes are not created during drilling;
2) Before and upon
installation of the surface casing, the following:
A) The
resistivity, spontaneous potential, and caliper logs before the casing is
installed; and
B) A
cement bond and variable density log, to evaluate cement quality radially, and
a temperature log after the casing is set and cemented;
3) Before
and upon installation of the long-string casing, the following:
A) The
resistivity, spontaneous potential, porosity, caliper, gamma ray, fracture
finder logs, and any other logs the Agency requires for the given geology
before the casing is installed; and
B) A
cement bond and variable density log and a temperature log, after the casing is
set and cemented;
4) A
series of tests designed to demonstrate the internal and external mechanical
integrity of injection wells, which may include the following:
A) A pressure test with
liquid or gas;
B) A tracer survey, such as
oxygen-activation logging;
C) A temperature or noise
log; and
D) A casing inspection log;
and
5) Any
alternative methods that provide equivalent or better information and which are
required by or approved of by the Agency.
b) The
owner or operator must take whole cores or sidewall cores of the injection zone
and confining system and formation fluid samples from all injection zones, and
the owner or operator must submit a detailed report prepared by a log analyst
to the Agency that includes the following information: well log analyses (including
well logs), core analyses, and formation fluid sample information. The Agency
must accept information on cores from nearby wells if the Agency determines
that the owner or operator has demonstrated that core retrieval is not possible
and the nearby cores are representative of conditions at the well. The Agency
must require the owner or operator to core other formations in the borehole if
the Agency determines that coring those other formations is necessary for
evaluation of the well project.
c) The
owner or operator must record the fluid temperature, pH, conductivity,
reservoir pressure, and static fluid level of each injection zone.
d) At a
minimum, the owner or operator must determine or calculate the following
information concerning the injection and confining zones:
1) The fracture pressure;
2) Other
physical and chemical characteristics of the injection and confining zones; and
3) The
physical and chemical characteristics of the formation fluids in each injection
zone.
e) Upon completion,
but prior to operation, the owner or operator must conduct the following tests
to verify hydrogeologic characteristics of each injection zone:
1) A pressure fall-off
test and a pump test; or
2) A pressure fall-off
test and injectivity tests.
f) The
owner or operator must provide the Agency with the opportunity to witness all
logging and testing by this Subpart H. The owner or operator must submit a
schedule of these activities to the Agency no later than 30 days prior to
conducting the first test, and the owner or operator must submit any changes to
the schedule to the Agency no later than 30 days prior to the next scheduled
test.
BOARD NOTE: This Section
corresponds with 40 CFR 146.87 (2011).