Current through all regulations passed and filed through December 16, 2024
(A) All class I
wells shall be sited in such a fashion that they inject into a formation which
is beneath the lowermost formation containing, within one-quarter mile of the
well bore, an underground source of drinking water.
(B) All class I wells shall be cased and
cemented to prevent the movement of fluids into or between underground sources
of drinking water. The casing and cement used in the construction of each newly
drilled well shall be designed for the life expectancy of the well. In
determining and specifying casing and cementing requirements, the following
factors shall be considered:
(1) Depth to the
injection zone.
(2)
Injection pressure, external pressure, internal pressure, and axial loading.
(4) Size and grade of all casing strings
(wall thickness, diameter, nominal weight, length, joint specification, and
construction material).
(5)
Corrosiveness of injected fluid, formation fluids, and temperatures.
(6) Lithology of injection and confining
intervals.
(7) Type or grade of
cement.
(C) All class I
injection wells, except those municipal wells injecting non-corrosive wastes,
shall inject fluids through tubing with a packer set immediately above the
injection zone, or tubing with an approved fluid seal as an alternative. The
tubing, packer, and fluid seal shall be designed for the expected service.
(1) The use of other alternatives to a packer
may be allowed with the written approval of the director. To obtain approval,
the operator shall submit a written request to the director, which shall set
forth the proposed alternative and all technical data supporting its use. The
director shall approve the request if the alternative method will reliably
provide a comparable level of protection to underground sources of drinking
water. The director may approve an alternative method solely for an individual
well or for general use.
(2) In
determining and specifying requirements for tubing, packer, or alternatives,
the following factors shall be considered:
(b)
Characteristics of injection fluid (chemical content, corrosiveness, and
density).
(e)
Rate, temperature and volume of injected fluid.
(3) All areas of a well that may come into
contact with corrosive wastes shall be constructed of corrosion-resistant
materials.
(D)
Appropriate logs and other tests shall be conducted during the drilling and
construction of new class I wells. A descriptive report interpreting the
results of such logs and tests shall be prepared by a knowledgeable log analyst
and submitted to the director. At a minimum, such logs and tests shall include:
(1) Deviation checks on all holes constructed
by first drilling a pilot hole, and then enlarging the pilot hole by reaming or
another method. Such checks shall be at sufficiently frequent intervals to
assure that vertical avenues for fluid migration in the form of diverging holes
are not created during drilling.
(2) Such other logs and tests as may be
needed after taking into account the availability of similar data in the area
of the drilling site, the construction plan, and the need for additional
information, that may arise from time to time as the construction of the well
progresses. In determining which logs and tests shall be required, the
following logs shall be considered for use in the following situations:
(a) For surface casing intended to protect
underground sources of drinking water:
(i) Resistivity,
spontaneous potential, and caliper logs before the casing is installed.
(ii) A cement bond, temperature, or density
log after the casing is set and cemented.
(b) For intermediate and long strings of
casing intended to facilitate injection:
(i)
Resistivity, spontaneous potential, porosity, and gamma ray logs before the
casing is installed.
(ii)
Fracture finder logs.
(iii) A cement bond,
temperature, or density log after the casing is set and cemented.
(E) At a
minimum, the following information concerning the injection formation shall be
determined or calculated for new class I wells:
(4) Other physical and chemical
characteristics of the injection matrix.
(5)
Physical and chemical characteristics of the formation fluids.
(6) Compatibility of injected fluids with
formation fluids.