Ohio Administrative Code
Title 3745 - Ohio Environmental Protection Agency
Chapter 3745-9 - Water Well Standards
Section 3745-9-10 - Abandoned well, test hole, dry well sealing
Universal Citation: OH Admin Code 3745-9-10
Current through all regulations passed and filed through December 16, 2024
(A) An abandoned well, test hole, or dry well shall be sealed in accordance with this rule and rule 3745-9-07 of the Administrative Code.
(1) "The State of Ohio Regulations and
Technical Guidance For Sealing Unused Water Wells and Boreholes
" shall be used as a guide.
(2) Plan approval is not required in
accordance with Chapter 3745-91 of the Administrative Code to seal an abandoned
well, test hole or dry hole. A public water system may apply to the director
for a variance from this rule in accordance with rule
3745-9-02 of the Administrative
Code.
(B) A test hole shall either be permanently sealed or converted into a well upon completion of testing.
(C) An abandoned well shall be sealed in accordance with the following:
(1) All obstructions shall be removed from
the abandoned well, including the pump and related equipment, drop pipe,
pitless adapter, suction line, trash or other debris. Unless permanently
attached, all liner pipe shall be removed from the well prior to placement of
sealing materials.
(2) Casing shall
be removed, ripped or perforated, or with prior consultation with the district
office the casing may be left intact or in place.
(a) Casing shall be removed to a depth of at
least three feet below ground surface, except for a dug or bucket augered well
covered by paragraph (C)(13)(b)(ii) of this rule. The remaining borehole shall
be filled with clean clay.
(b) If
possible, casing shall be removed by overdrilling when the annular seal is
inadequate, or water is flowing from around the outside of the casing, or
gravel packing connects two or more hydraulic zones.
(3) Where evidence of microbiological growth
is present, an abandoned well shall be disinfected by slowly wetting the casing
or borehole with a solution of sodium hypochlorite or calcium hypochlorite.
Disinfectant concentration in the water column shall be at least fifty
milligrams per liter total chlorine.
(a)
Disinfectant shall have standard ANSI/NSF 60 certification.
(b) Contact of disinfectant with bentonite
shall be avoided.
(4)
Cement grout may be gravity poured into a dry hole where no water is
present.
(5) After the sealing
material and grout have been placed into the abandoned well, the grout shall
cure a minimum of twelve hours to assess whether any settling of the sealing
material has occurred. If settling has occurred, then additional grout shall be
placed into the remaining borehole.
(6) The finished grade shall ensure that
surface water runoff drains away from the sealed abandoned well.
(7) An abandoned well that is less than two
hundred feet deep and greater than four inches in diameter may be sealed using
coarse grade bentonite.
(8) An
abandoned well that is less than one hundred feet deep and greater than four
inches in diameter may be sealed using pelletized bentonite or coarse grade
bentonite.
(9) An abandoned well
that is constructed into or through a single aquifer that is not flowing at the
surface shall be sealed in accordance with the following:
(a) Clean and disinfected sand or gravel may
be placed either from the bottom of the abandoned well to the top of the
aquifer, or to twenty-five feet below ground surface, whichever is encountered
first.
(b) An abandoned well shall
be sealed by either pressure grouting, or pouring coarse grade bentonite from
twenty-five feet below ground surface to the ground surface.
(c) If casing is removed, sealing material
and grout shall be placed while casing is being removed from the
borehole.
(10) An
abandoned well that is constructed into or through multiple aquifers that is
not flowing at the surface shall be sealed in accordance with the following
requirements:
(a) An abandoned well shall be
sealed by pressure grouting.
(b)
Pelletized bentonite or coarse grade bentonite may be poured.
(c) If detailed construction and geologic
data is available, then clean and disinfected sand or gravel may be placed
adjacent to the aquifer zones and grout placed adjacent to the confining units.
The abandoned well shall then be sealed from the top of the uppermost aquifer
or from twenty-five feet below ground surface, whichever is encountered first,
to the surface with either cement grout or bentonite grout.
(11) An abandoned well that is
flowing shall be sealed in accordance with the following requirements:
(a) If practical, the casing may be extended
until the flow of water over the top of the casing stops. An abandoned well
shall be sealed by pressure grouting, or coarse grade or pelletized bentonite
may be poured.
(b) If casing
extension is impractical because of the hydraulic head, one of the following
shall be met:
(i) An inflatable packer shall
be installed at the top of the producing formation to stop or restrict the flow
of water. The abandoned well shall be sealed by pressure grouting through the
packer from the bottom of the hole to the bottom of the packer. The packer
shall then be deflated and pressure grouting shall continue to the ground
surface.
(ii) A shut-in device
shall be installed at the top of the abandoned well to prevent flow. A
conductor pipe shall be inserted through the shut-in device and the abandoned
well shall be sealed by pressure grouting from the bottom of the hole to the
ground surface.
(iii) Disinfected
gravel shall be poured into the abandoned well to reduce the flow of water and
the abandoned well shall be sealed by pressure grouting from the top of the
aquifer, or from twenty-five feet below ground surface, whichever is
encountered first.
(iv) If
additives are used to increase the density of cement grout to control the flow
of water, appropriate placement techniques shall be used to ensure that
separation does not occur.
(12) An abandoned well drilled through
fractured or cavernous formations or a mine shaft, shall be sealed in
accordance with the following:
(a) The depth
and thickness of the fractured, cavernous zone or mine shaft shall be
determined, if possible, and the fractured, cavernous zone or mine shaft shall
be sealed in accordance with the following:
(i) Where the fractured, cavernous zone or
mine shaft is greater than twenty-five feet from the ground surface, a packer,
shale trap, or another similar device shall be installed at the top of the
fractured, cavernous zone or mine shaft and the well shall then be sealed by
pressure grouting up to the ground surface. In lieu of installing a packer,
shale trap, or another similar device, the fractured, cavernous zone or mine
shaft may be filled with clean and disinfected gravel, or cement grout, and the
abandoned well shall then be sealed by pressure grouting up to the ground
surface.
(ii) Where the fractured,
cavernous zone or mine shaft is less than twenty-five feet from the ground
surface, the abandoned well shall be filled with cement grout with additives
that promote bridging across the fractured, cavernous zone or mine
shaft.
(b) The remainder
of the abandoned well shall be sealed by pressure grouting.
(13) A dug or bucket auguered
abandoned well that is greater than twenty-four inches in diameter and less
than twenty-five feet deep shall be sealed in accordance with
one of the following:
(a)
The entire depth
of the dug abandoned well shall be filled with concrete that meets the
specifications of paragraph (B)(1)(c) of rule
3745-9-07 of the Administrative
Code and the concrete mix shall not exceed aggregate sizes greater than medium
sand or three-fourths inch gravel.
(b)
The static water level shall be measured and the abandoned well pumped dry, if
possible.
(c) If the static water
level is less than five feet below ground surface, then the following apply:
(i) The abandoned well shall be filled with
clean clay or cement grout to the elevation of the static water
level.
(ii) The liner shall be
removed to the depth of the static water level, and the borehole shall be
excavated radially six inches beyond the original borehole.
(iii) A one foot layer of bentonite or cement
grout shall be placed in the abandoned well at the elevation of the static
water level. If the abandoned well is dry and bentonite is used, it shall be
hydrated with five gallons of water per fifty pounds of bentonite.
(iv) The remaining borehole shall be filled
with clean clay to ground surface.
(d) If the static water
level is greater than five feet below ground surface, then the following apply:
(i) The abandoned well shall be filled with
clean clay or cement grout to the elevation of the static water
level.
(ii) At least the top three
feet of casing, wall or liner material shall be removed and the borehole shall
be excavated radially six inches beyond the original borehole.
(iii) A one foot layer of bentonite or cement
grout shall be placed in the abandoned well at the elevation of the static
water level. If the abandoned well is dry and bentonite is used, it shall be
hydrated with five gallons of water per fifty pounds of bentonite.
(iv) A layer of clean clay or cement grout
shall be added above the grout until the level in the abandoned well is three
feet below ground surface.
(v)
Another one foot thick layer of bentonite or cement grout shall be added at the
level at which the casing, wall or liner material was removed. If the abandoned
well is dry, the bentonite shall be hydrated with five gallons of water per
fifty pounds of bentonite.
(14) A dug or bucket auguered abandoned well
that is greater than twenty-four inches in diameter and greater than
twenty-five feet deep shall be sealed in accordance with either paragraph
(C)(9) or (C)(10) of this rule.
(D) A copy of the well sealing report that is required by section 1521.05 of the Revised Code shall be submitted to the district office within thirty days of sealing a public water system well. The abandoned well location shall be clearly noted on a site map with reference to highways, streets, corporate boundaries and local physical landmarks.
[Comment: For dates of non-regulatory government publications, publications of recognized organizations and associations, test methods, federal rules, and federal statutory provisions referenced in this rule, see paragraph (AA) of rule 3745-9-01 of the Administrative Code titled "Incorporation by reference."]
Disclaimer: These regulations may not be the most recent version. Ohio may have more current or accurate information. We make no warranties or guarantees about the accuracy, completeness, or adequacy of the information contained on this site or the information linked to on the state site. Please check official sources.
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