Ohio Administrative Code
Title 3745 - Ohio Environmental Protection Agency
Chapter 3745-9 - Water Well Standards
Section 3745-9-09 - Well development and pumping test
Universal Citation: OH Admin Code 3745-9-09
Current through all regulations passed and filed through December 16, 2024
(A) A public water system well shall be developed upon completion to remove the native silts and clays, drilling mud or finer fraction of the filter pack until turbidity or sand content in the well is minimal.
(1) Mechanical development shall
be performed so as not to cause damage to the components of the well.
Mechanical development techniques include: mechanical surging; air surging or
air lifting; overpumping and backwashing; high velocity jetting; bailing; and
hydrofracturing.
(2) With prior
consultation with the district office, chemical development procedures may be
used in conjunction with mechanical procedures. Chemical development techniques
include use of an acid or dispersant that has standard ANSI/NSF 60
certification. The director may require submission of chemical development
procedures with specifications for the method, equipment, chemicals, and
testing for residual chemicals.
(a)
Dispersants that contain phosphorous compounds shall not be used during the
development of a well.
(b)
Dispersant may be used to disaggregate clay particles to enhance removal.
Dispersant shall be immediately flushed from the well and aquifer to prevent
bacterial growth in the aquifer.
(c) Dispersant shall be premixed and used
according to the manufacturer's recommendations.
(d) Acid shall be used according to the
manufacturer's recommendations. Proper pH shall be maintained in the borehole
to ensure the effective action of the acid.
(B) A pumping test shall be conducted upon completion of development of the public water system well and conform to the following:
(1) Be used to
calculate the specific capacity of the well at the
anticipated permanent design pumping rate for all high
use wells intended to serve as a source to a community public water
system.
(2) Be used to
demonstrate that the well can supply water at the anticipated permanent design
pumping rate while at a minimum maintaining the operational capacity of the
well field and without degrading the water quality of any well in the well
field.
(3) The determination of a
permanent design pumping rate for a new public water system well shall include
analysis of the effects of interference drawdown from other wells owned by the
public water system as well as other high capacity wells not owned by the
public water system. Operational practices and the potential to cause
degradation of water quality at the well field should also be considered when
establishing a permanent design pumping rate for a new public water system
well.
(4) The pumping test
classification is determined from the estimated average daily water demand of
the well and type of water system, as illustrated in the following table.
Estimated average daily water demand may be determined by the director from the
design pumping rate of the well. With prior consultation, the director may
accept an alternative constant rate pumping test that is conducted under the
supervision of a qualified ground water professional or person with
demonstrated competency in performing pumping or aquifer tests.
|
Pumping Test Classification |
Estimated Average Daily Demand of the Well (gallons per day) |
|
Low use |
0 to 10000 |
|
Medium use |
10001 to 100000 |
|
High use |
greater than 100000 |
Acceptable pumping tests for low, medium and high use classifications are as follows:
(a)
For low or medium use wells, the pumping test shall be conducted at a constant
rate for a period of at least normal operation either at the peak hourly
demand, or at least 1.5 times the anticipated permanent design pumping rate, whichever is greater
. If
the well cannot sustain peak hourly demand, the pumping test shall be conducted
at a minimum of 1.5 times the anticipated design pumping rate. For a
community water system well, the duration of the constant rate pumping test
shall be no less than twenty-four hours.
(b) For all high use wells, a step-drawdown
test shall be conducted, followed by a constant rate pumping test.
(i) The step-drawdown test shall be used to
obtain sufficient hydrogeologic information to design an appropriate constant
rate pumping test for the well. The step-drawdown test shall, at a minimum
conform to the following:
(a) Consist of three
or more steps of progressively increasing pumping rates.
(b)
One step shall be
performed at the anticipated permanent design pumping rate.
(c)
Each step shall be of approximately equal duration.
(d) Each step shall be
performed
at a constant pumping rate for no less than forty-five minutes.
(ii) The constant rate pumping
test shall be conducted for at least twenty-four hours at a pumping rate of at
least 1.5 times the anticipated permanent design pumping rate. The constant
rate pumping test shall not commence until the water level has recovered to at
least ninety per cent of the drawdown caused by the step-drawdown test or
twenty-four hours after the completion of the step-drawdown test, whichever
comes first.
(c) The
public water system shall consult with the Ohio environmental protection agency
to determine if the constant rate pumping test will need to extend beyond
twenty-four hours if any of the following conditions exist at the time a new
well site is proposed or can be expected to result from the well's operation:
(i) Pumping at the new well may cause
interference with existing wells.
(ii) Prolonged pumping at the new well may
cause changes in water quality.
(iii) The well will have special design
criteria such as a radial collector well.
(iv) Information about the aquifer's response
to pumping is needed for ground water modeling.
[Comment: If any of these conditions exist, the public water system should consult with a qualified ground water professional to design and implement a pumping test or tests which will address the noted condition.]
(d)
For low, medium or high use wells, the constant rate pumping test may be
conducted at a lower pumping rate if there is concern that pumping the well at
1.5 times the anticipated permanent pump design rate will be overly excessive,
will not be possible, or will have adverse effects on the long-term performance
of the well or aquifer. The test may be conducted at a lower pumping rate if
the following criteria are met:
(i) The
constant rate pumping test is conducted at no less than 1.2 times the pump
design rate.
(ii) A demonstration
is provided that supports the reasoning for a lower pumping rate that even
under adverse conditions, including but not limited to severe drought, the well
will likely be able to supply water at the anticipated permanent design pumping
rate over the anticipated functional life of the well.
[Comment: If the permanent pump design rate will not be known until after the constant rate test, then the maximum permanent pump design rate will be based on back-calculation of the pumping rate used for the constant rate test. For example, if the constant rate test is performed at three hundred gallons per minute, the maximum permanent pump design rate will then be two hundred gallons per minute if the 1.5 times factor is used or two hundred and fifty gallons per minute if the 1.2 times factor is used.]
(5) The pumping test
shall include the following:
(a) The flow rate
shall be measured using an orifice weir with manometer, or equivalent method
acceptable to the director.
(b)
During a step-drawdown or constant rate pumping test, water level measurements
shall be taken from the well starting with the static water level and
continuing during drawdown to the nearest 0.1 foot, as measured from an
identified datum.
(i) Water level measurements
shall be at the following time intervals:
|
Time After Test Started (minutes) |
Time Interval Between Measurements (minutes) |
|
0 - 15 |
1 |
|
16 - 60 |
5 |
|
61 - 120 |
10 |
|
121 - 180 |
20 |
|
181 - 300 |
30 |
|
Greater than 300 |
60 |
(ii)
Recovery water level measurements shall be taken immediately after termination
of the constant rate pumping test at time intervals of five minutes for the
first hour and every thirty minutes thereafter until the water level has
recovered to at least ninety per cent of the drawdown caused by the pumping
test, twenty-four hours after the completion of the pumping test, or recovery
is interrupted by pumping of another well, whichever occurs first.
(iii) For high use wells, all pumping tests
shall include water level measurements from observation or surrounding wells.
An observation well shall be selected or sited such that the water level
measurements obtained before, during and after the pumping test will, upon
analysis, provide information about the aquifer's response to pumping. The
selection or siting process shall consider the distance between the observation
well and the pumping well, the type of aquifer from which water is being
withdrawn, the hydraulic gradient and other aquifer characteristics.
(6) The well owner
shall submit a report of the pumping tests with their results, interpretations
and conclusions.
(a) The pumping test report
shall include the following:
(i) The date and
times of starting through ending the pumping test.
(ii) A data table for each well used to
observe the drawdown and recovery water level measurements, as required by
paragraph (B)(5)(b) of this rule, showing the time after the pump test started
and the corresponding water level measurements to the nearest 0.1
foot.
(iii) The height above ground
(in feet) of the water level measurement reference point.
(iv) The pumping rate and depth at which the
pump used for the test was set.
(v)
The anticipated permanent pump setting depth (in feet below ground).
(vi) The specific capacity of the well at the
tested pumping rates.
(vii)
For high use wells only,
the
specific capacity of the well at the anticipated permanent design pumping rate
after
drawdown has stabilized.
(b) In addition to paragraph (B)(6)(a) of
this rule, the report for a high use well pumping test report shall include the
following:
(i) A map showing the location of
the pumping wells and the location of other wells used to observe drawdown. The
map shall, at a minimum, include the names of the wells as used in the report
and the distance between the pumping well and other wells used to observe
drawdown.
(ii) Graphs plotted on
semi-logarithmic graph paper showing the drawdown measurements on the
arithmetic scale and time on the logarithmic scale.
Graphs must be submitted for the pumping well and any other wells used to observe drawdown and recovery during the pumping test.
(iii) Graphs plotted on
semi-logarithmic graph paper showing the recovery measurements on the
arithmetic scale and time on the logarithmic scale.
Graphs must be submitted for the pumping well and any other wells used to observe drawdown and recovery during the pumping test.
(iv) Arithmetic graphs showing all
water-level data collected during the pumping test and recovery period from the
pumping well and all observation wells.
(c) In addition to paragraph (B)(6)(b) of
this rule, when a high use community water system well is part of a
multiple-well system the report shall include documentation that the well meets
the demonstration requirements in paragraphs (B)(2) and (B)(3) of this
rule.
(C) Samples shall be collected and analyzed from a public water system well for contaminants at the conclusion of the constant rate pumping test, performed in accordance with paragraph (B) of this rule, and prior to initiation of the recovery period.
(1) A
community water system well shall be sampled and analyzed for the contaminants
that are listed in appendix A of this rule, "Required Analyses for Wells
Utilized by Community Public Water Systems."
(2) A nontransient noncommunity water system
well shall be sampled and analyzed for the contaminants that are listed in
appendix B of this rule, "Required Analyses for Wells Utilized by Nontransient
Noncommunity Public Water Systems."
(3) A transient noncommunity water system
well shall be sampled and analyzed for the contaminants that are listed in
appendix C of this rule, "Required Analyses for Wells Utilized by Transient
Noncommunity Public Water Systems."
(4) The director may reduce or add to the
contaminants that are listed in the appendices to this rule because of well
siting, well construction, treatment, promulgated drinking water standards, or
other criteria to assess if the ground water is acceptable for human
consumption.
(5) Samples that are
collected from a public water system well in accordance
with this
rule shall be analyzed in a laboratory certified to analyze drinking water for
contaminants in accordance with Chapter 3745-89 of the Administrative Code. The
analytical methods shall be the same as required by the entry point to the
distribution system monitoring in accordance with rule
3745-81-27 of the Administrative
Code and shall include all the volatile organic and synthetic organic analytes
that are quantified by the laboratory for the organic analytical method.
Per- and polyfluoroalkyl substances (PFAS) shall be
analyzed using EPA analytical method 533 or EPA method 537.1.
[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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