North Dakota Administrative Code › Title 33.1 - Department of Environmental Quality › Article 33.1-18 - Water Well Contractors › Chapter 33.1-18-01 - Water Well Construction and Water Well Pump Installation › Appendix - Appendix

Current through Supplement No. 393, July, 2024
I. WELL DISINFECTION.
A. General.
Immediately after construction or repair, always disinfect
				  with a strong chlorine solution of fifty to one hundred milligrams per liter.
				  Materials used in construction or repair of a well are contaminated with dirt
				  and bacteria and the water from a well is considered safe to drink only when
				  laboratory tests show that no harmful bacteria are present.
B. Procedure.
1. Determine the amount of water in the well by referring to
				  the table.
2. Add the amount of chlorine compound necessary to give a
				  dosage of fifty milligrams per liter as indicated on the table, into the
				  opening between the casing and the drop pipe. On new well construction, the
				  chlorine should be added just before installation of the pumping
				  equipment.
a. Chlorine tablets may be dropped in the top of the well
				  and allowed to settle to the bottom.
b. Deep wells with high water levels may require that
				  chlorine solutions be added through a hose inserted down the well casing to
				  ensure proper diffusion of the chlorine.
Chlorine can destroy only the bacteria with which it comes
				  in contact. Agitation of the water in the well may be required to assure
				  thorough mixing. After adding the chlorine, start the pump and operate until
				  the odor of chlorine is detected at the pump discharge.
3. The storage and distribution system should be disinfected
				  along with the well. Open the house faucets and let the water run until the
				  odor of chlorine is apparent.
4. Allow the chlorine solution to remain in the well and
				  distribution system for a period of twenty-four hours. Pump the well and flush
				  the distribution system to remove all traces of chlorine.
5. After pumping, collect a water sample and submit to a
				  laboratory for a bacteriological analysis to assure the safety of the water
				  supply. If contamination is shown to be still present in the water supply, the
				  chlorination procedure should be repeated.
6. When time does not permit well disinfection by the
				  procedure previously described, apply to the entire depth of the well a total
				  volume of 50 mg/l chlorine solution at least four times greater than the volume
				  of water in the well. Allow the chlorine solution to remain in the well for a
				  period of at least two hours. Pump the well and flush the distribution system
				  to remove all traces of chlorine.
QUANTITY OF DISINFECTANT REQUIRED TO GIVE A
						  DOSE OF 50 MILLIGRAMS PER LITER CHLORINE
Diameter of Well,
Ounces of Disinfectant Per 10-Ft.Depth of
						  Water
Spring, or Pipe, in Inches
Gallons of Water Per Foot of Water Depth
65% Calcium Hypochlorite
5 1/4% Sodium Hypochlorite*
2
0.16
0.02
0.21
3
0.37
0.04
0.47
4
0.65
0.07
0.83
5
1.00
0.10
1.30
6
1.47
0.15
1.87
8
2.61
0.27
3.32
10
4.08
0.31
5.19
12
5.88
0.60
7.47
18
13.22
1.36
16.80
24
23.50
2.41
29.87
36
52.88
5.43
67.20
48
94.01
9.65
119.47
*Sodium Hypochlorite, also known as Bleach, Clorox, etc.,
				  can be purchased at most drug and grocery stores.
One heaping tablespoon of 65% calcium hypochlorite =
				  approximately 1/2 oz.
Six (6) 65% calcium hypochlorite tablets = approximately 1
				  oz.
Heavy concentrations of chlorine on or near the well screen
				  with waters very high in iron and/or iron bacteria may result in oxidation of
				  iron on the well screen. Efficiency of the well screen and well output could be
				  reduced under such conditions.
II. LABORATORY SERVICE.Chemical and microbiological
				  laboratory service is provided by the department of environmental quality
				  laboratory located at 1205 Avenue A West, Bismarck, North Dakota.Mailing
				  address is:
Department of Environmental Quality
Division of Laboratory Services
P.O.Box 937
Bismarck, ND 58502
Microbiological laboratory service is available from:
First District Health Unit 801 11th Avenue SW P.O.Box
						  1268 Minot, ND 58702-1268
Southwestern District Health Unit 2869 Third Avenue West
						  Dickinson, ND 58601
Fargo Cass Public Health Environmental Laboratory 435
						  14th Avenue South Fargo, ND 58103
Grand Forks EnvironmentalLaboratory 503 South Fourth
						  Street Grand Forks, ND 58201
III. RECOMMENDED PROCEDURES.
A. Plumbness and Alignment.
Every public water well, before being officially accepted,
				  should be tested for plumbness and alignment.The test method to be followed
				  should be clearly stated in the specifications. As a minimum, a forty-foot
				  [12.19-meter] section of pipe, or rigid dummy of the same length, having an
				  outside diameter not more than one-half inch [12.7 millimeters] smaller than
				  the diameter of the casing or hole being tested, shall move freely throughout
				  the length of the casing or hole to the lowest anticipated pump setting. The
				  well should not vary from the vertical in excess of two-thirds of the smallest
				  inside diameter of that part of the well being tested, per one hundred feet
				  [30.48 meters] of depth.
B. Abandoned Wells.
For detailed procedures for abandoning wells, see Section
				  A1-13, Sealing Abandoned Wells, AWWA Standards for Deep Wells, A100-66 or later
				  amendments prepared by the American Water Works Association and the National
				  Water Well Association.
C. Springs.Springs should be considered as a water supply
				  only when it is not possible to develop an acceptable well.Springs shall be
				  protected from entry of surface water and should be housed in a permanent
				  structure. Continuous chlorination of springs is recommended to assure the
				  bacterial purity of the water supply.
D. Continuous Chlorination of Public Well Water Supplies.
				  Continuous chlorination is recommended for the safeguarding of public well
				  water supplies. Chlorination not only assists in maintaining the bacterial
				  purity of the water, but also eliminates the growth of taste-and-odor-producing
				  nuisance organisms.
E. Livestock Wells.
A check valve on the pump discharge line is not required on
				  nonpressurized wells for livestock use that would be damaged by freezing. The
				  pump discharge line shall have a minimum airgap equal to twice the effective
				  diameter of the discharge line to prevent backflow or siphonage into the well
				  to prevent contamination of the well.
IV. MEASUREMENT OF WATER WELL DRAWDOWN AND SPECIFIC
				  CAPACITY.
Pumping tests of water supply wells can serve many purposes.
				  Properly planned and conducted tests will reveal information about the
				  performance and efficiency of the well being pumped. In addition, from the data
				  obtained, calculations can be made which interpret ground water aquifer
				  performance.
Measuring each well for pump and well yield, depth to water
				  level, drawdown, and specific capacity should be done on a routine basis. These
				  test results should be compared with previous tests to estimate current well
				  and/or aquifer conditions.
A. Terminology.
It is important to understand the meaning of the terms used
				  relating to the pumping test. Some of these terms are as follows:
1. Static Water Level. This is the level at which water
				  stands in the well when no water is being pumped. It is generally expressed as
				  the distance in feet from the ground surface to the water level in the
				  well.
2. Pumping Level. This is the level at which water stands in
				  the well when pumping is in progress. The pumping level may also be referred to
				  as the dynamic water level.
3. Drawdown. When a well is pumped, the water level in the
				  vicinity of the well will be lowered. Drawdown is the difference, measured in
				  feet, between the static water level and the pumping level.
4. Well Yield. The well yield is the volume of water per
				  unit of time discharged from a well either by pumping or by free flow.
5. Specific Capacity. Specific capacity of the well is its
				  yield per unit of drawdown, usually expressed as gallons per minute (gpm) per
				  foot of drawdown.
B. Determination of Depth to Water Level.
1. Wetted Tape Method. The wetted tape method will
				  accurately measure the depth to water in a well and can be used for depths up
				  to one hundred feet [30.5 meters] or more. Attach a lead weight to the end of a
				  steel measuring tape, if needed. Wipe dry the lower three or four feet [.91 or
				  1.22 meters] of the tape and coat with carpenter's chalk. Lower the tape into
				  the well through the air vent or other opening until part of the chalked
				  section is below water. Continue to lower the tape until the next even foot
				  mark can be held exactly at a reference point and record the number of feet
				  indicated. The tape is then removed from the well and note is made of the
				  footage of chalked section washed away by the water. Subtract this reading from
				  the reading obtained at the top reference point. The difference in these
				  readings is the depth from the reference point to the water level.
2. Air Line Method. The air line method measures depth to
				  water level by determining the air pressure required to push all of the water
				  out of a submerged tube of known length. The air line consists of a one-fourth
				  inch [6.35 millimeters] pipe, copper or plastic tubing, extending from the top
				  of the well to a point several feet below the lowest anticipated water level.
				  To avoid turbulence near the intake of the pump, the lower end of the air line
				  should be at least five feet [1.52 meters] above or below the point where water
				  enters the pump. The exact length of the air line must be known or should be
				  measured as it is placed in the well. Make all joints airtight with white lead
				  or piping compound. The upper end of the tube is fitted with suitable
				  connections for an air gauge, a tire valve, and an air pump.
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Pump the air into the line until the gauge pressure is
				  constant. This indicates that all of the water has been expelled from the tube.
				  The gauge reading shows the pressure necessary to support a column of water of
				  a height equal to the depth the tube was submerged. If the gauge indicates feet
				  of water, then it shows directly the submerged length of the line in feet.
				  Subtracting the submerged length from the total length of the air line gives
				  the depth to static water level. Gauges calibrated in pounds per square inch
				  (psi) may be converted to feet of water by multiplying by 2.31.
C. Determination of Drawdown.
Example:
Depth to water before pumping
						  =
100 feet
Depth to water after pumping =
125 feet
Drawdown
= Depth after pumping - depth before
						  pumping
= 125 feet - 100 feet = 25 feet
First, determine the static water level. Second, after the
				  well has achieved a constant pumping rate or yield, measure the depth to the
				  water level. The difference of these readings before and after pumping the well
				  at a specific rate is measured in feet and recorded as feet of drawdown.
D. Determination of Specific Capacity.
Example:
Yield of well
=
160
						  gpm
Drawdown
= 20
feet Specific
						  capacity
=
160/20
=
8 gpm per foot of
						  drawdown
Specific capacity is calculated by dividing the yield of the
				  well in gallons per minute by the drawdown. Both measurements shall be taken at
				  the same time.
E. Interpretation of Water Well Problems.
With proper records of water well tests, well problems can
				  be interpreted. Some rules to follow are:
1. If the output of the well (gpm) drops, the drawdown
				  decreases, and the specific capacity remains the same, the problem is most
				  likely the pump.
2. If the output of the well (gpm) drops, the static water
				  level remains the same, the drawdown increases and the specific capacity
				  decreases, the well may be plugging. Acid clean the well when the specific
				  capacity drops about twenty-five percent.
3. If the output of the well (gpm) drops and the static water
				  level is declining, the aquifer may be depleting.
V. GENERAL POLICY - GEOTHERMAL ENERGY.
Geothermal energy is the renewable thermal energy of the
				  earth or ground water. Using this form of energy for heating and cooling
				  purposes has become increasingly popular for both commercial and residential
				  purposes. Geothermal regulations are administered by the North Dakota
				  Geological Survey, and require a permit from the State Geologist prior to the
				  installation of a geothermal system. All construction of geothermal energy
				  systems must comply with the rules contained in
				  chapter
				  43-02-07, Geothermal
				  Energy Production. These regulations cover both vertical-loop and
				  horizontal-loop systems. Installers should contact the North Dakota Geological
				  Survey for more information regarding installation of geothermal energy
				  systems.
Because of the potential for contamination of drinking water
				  systems and aquifers, and the pollution of surface waters, the department
				  provides the following guidance for users of geothermal energy. This policy
				  relates primarily to private individual systems. Commercial and industrial
				  projects should be constructed only after consultation with the department
				  regarding water supply and disposal requirements and the North Dakota
				  Geological Survey regarding construction permitting requirements.
1. The department encourages the conservation of ground
				  water resources, therefore, closed-loop geothermal systems are recommended.
				  Closed-loop systems also have fewer maintenance problems. If an open-loop
				  system is constructed, whenever possible, the water should be reinjected into
				  the supply aquifer or used for other beneficial purposes such as irrigation or
				  stock watering.
2. Users of open-loop geothermal energy systems must be
				  aware of the scale-forming or corrosive nature of some of the highly
				  mineralized water in North Dakota. Some ground water supplies may require
				  treatment prior to use, or serious problems with operation of the heat exchange
				  system can develop. Chemicals used for cleaning the heat exchange system, and
				  the material removed through cleaning, may not be suitable for discharge to the
				  storm sewer system. Problems with the development of scale will often reduce
				  the volume of water that can be disposed into injection wells.
3. All supply and disposal wells shall be constructed to
				  comply with department rules,
				  33-18-01, "Water Well
				  Construction and Water Well Pump Installation". The geothermal system should be
				  constructed to eliminate all sources of contamination to the water supply
				  system and the ground water aquifer.
4. If municipal water supply systems are to be used as a
				  source of geothermal energy, an approved backflow prevention device shall be
				  used to separate the geothermal energy from the public water supply
				  system.
5. To protect the drinking water supply, heat exchangers,
				  unless otherwise permitted under the North Dakota state plumbing code, shall be
				  of double-wall construction with a space between the two walls which is vented
				  to the atmosphere.
6. Geothermal energy systems shall not discharge water to
				  either municipal drinking water or sanitary sewer systems. Discharge to the
				  municipal drinking water system is a cross-connection and could result in
				  chemical and/or microbiological contamination of the system. Nearly all cities
				  in the state have sewer use ordinances specifically prohibiting the connection
				  of clear water discharges to the sewer system.
7. Geothermal energy systems may discharge to municipal
				  storm sewer systems with approval of the municipality, and if the discharge
				  water is compatible with the waters of the receiving stream. Degradation of
				  surface waters by discharges from geothermal energy systems will not be
				  allowed.
8. If water is to be reinjected into the ground water system,
				  the discharge should be made to a similar or inferior quality aquifer.
9. Highly mineralized or saline waters, such as from the
				  Dakota formation, should be returned to those aquifers if secondary use is not
				  possible.
10. Evaporation ponds, which do not discharge, may be used as
				  a means of disposal where other methods of disposal are not feasible.
11. Disposal permits under the Underground Injection Control
				  Program or the National Pollutant Discharge Elimination System Regulations may
				  be required. Users of geothermal energy systems should contact the department
				  to determine whether a permit is required for their installation.
VI. ABANDONMENT OF TEST HOLES, PARTIALLY COMPLETED WELLS, AND
				  COMPLETED WELLS.
Reprinted from AWWA Standard for Water Wells, A100-84, by
				  permission. Copyright © 1984, American Water Works Association.
Section 1.1 - General
The recommendations contained in this appendix pertain to
				  wells and test holes in consolidated and unconsolidated formations. Each
				  sealing job should be considered as an individual problem, and methods and
				  materials should be determined only after carefully considering the objectives
				  outlined in the standard.
Section 1.2 - Wells in Unconsolidated Formations
Normally, abandoned wells extending only into consolidated
				  formations near the surface and containing water under water-table conditions
				  can be adequately sealed by filling with concrete, grout, neat cement, clay, or
				  clay and sand. In the event that the water-bearing formation consists of coarse
				  gravel and producing wells are located nearby, care must be taken to select
				  sealing materials that will not affect the producing wells. Concrete may be
				  used if the producing wells can be shut down for a sufficient time to allow the
				  concrete to set. Clean, disinfected sand or gravel may also be used as fill
				  material opposite the water-bearing formation. The remainder of the well,
				  especially the upper portion, should be filled with clay, concrete, grout, or
				  neat cement to exclude surface water. The latter method, using clay as the
				  upper sealing material, is especially applicable to large-diameter abandoned
				  wells.
In gravel-packed, gravel-envelope, or other wells in which
				  coarse material has been added around the inner casing to within twenty to
				  thirty feet [6.1 to 9.1 meters] of the surface, sealing outside the casing is
				  very important. Sometimes this sealing may require removal of the gravel or
				  perforation of the casing.
Section 1.4 - Wells in Noncreviced Rock Formations
Abandoned wells encountering noncreviced sandstone or other
				  water-bearing consolidated formations below the surface deposits may be
				  satisfactorily sealed by filling the entire depth with clay, provided there is
				  no movement of water in the well. Clean sand, disinfected if other producing
				  wells are nearby, may also be used through the sandstone up to a point ten to
				  twenty feet [3.0 to 6.1 meters] below the bottom of the casing. The upper
				  portion of this type of well should be filled with concrete, neat cement,
				  grout, or clay to provide an effective seal against entrance of surface water.
				  If there is an appreciable amount of upward flow, pressure cementing or mudding
				  may be advisable.
Section 1.5 - Multiple Aquifer Wells
Some special problems may develop in sealing wells extending
				  into more than one aquifer. These wells should be filled and sealed in such a
				  way that exchange of water from one aquifer to another is prevented. If no
				  appreciable movement of water is encountered, filling with concrete, neat
				  cement, grout, or alternate layers of these materials and sand will prove
				  satisfactory. When velocities are high, the procedures outlined in section 1.6
				  are recommended. If alternate concrete plugs or bridges are used, they should
				  be placed in known nonproducing horizons or, if locations of the nonproducing
				  horizons are not known, at frequent intervals. Sometimes when the casing is not
				  grouted or the formation is nocaving, it may be necessary to break, slit, or
				  perforate the casing to fill any annular space on the outside.
Section 1.6 - Wells With Artesian Flow
The sealing of abandoned wells that have a movement of water
				  between aquifers or to the surface requires special attention. Frequently the
				  movements of water may be sufficient to make sealing by gravity placement of
				  concrete, cement grout, neat cement, clay, or sand impractical. In such flow,
				  if preshaped or precast plugs are used, they should be several times longer
				  than the diameter of the well, to prevent tilting.
Since it is very important in wells of this type to prevent
				  circulation between formations or loss of water to the surface or to the
				  annular space outside the casing, it is recommended that pressure cementing,
				  using the minimum quantity of water that will permit handling, be used. The use
				  of wells, large stone aggregate (not more than one-third of the diameter of the
				  hole), lead wool, steel shavings, a well packer, or a wood or cast-lead plug or
				  bridge will be needed to restrict the flow and thereby permit the gravity
				  placement of sealing material above the formation producing the pressure
				  mudding instead of this process if sometimes permissible.
In wells which the hydrostatic head producing flow to the
				  surface is low, the movement of water may be arrested by extending the well
				  casing to an elevation above the artesian-pressure surface. Previously
				  described sealing methods suitable to the geologic conditions can then be
				  used.
Section 1.7 - Sealing Materials
A number of materials that can be used for sealing wells
				  satisfactorily, including concrete, cement grout, neat cement, clay, sand, or
				  combinations of these materials, are mentioned in this appendix. Each material
				  has certain characteristics and distinctive properties; therefore, one material
				  may be especially suited for doing a particular job. The selection of the
				  material must be based on the construction of the well, the nature of the
				  formations penetrated, the material and equipment available, the location of
				  the well with respect to possible sources of contamination, and the cost of
				  doing the work.
Concrete is generally used for filling the upper part of the
				  well or water-bearing formations, for plugging short sections of casings, or
				  for filling large-diameter wells. Its use is cheaper than neat cement or grout,
				  and it makes a stronger plug or seal. However, concrete will not penetrate
				  seams, crevices, or interstices. Furthermore, if not properly placed, the
				  aggregate is likely to separate from the cement.
Cement grout or neat cement and water are far superior for
				  sealing small openings, for penetrating any annular space outside of casings,
				  and for filling voids in the surrounding formation. When applied under
				  pressure, they are strongly favored for sealing wells under artesian pressure
				  or those encountering more than one aquifer. Neat cement is generally preferred
				  to grout because it does not separate.
Clay, as a heavy mud-laden or special clay fluid applied
				  under pressure, has most of the advantages of cement grout. Its use is
				  preferred by some competent authorities, particularly for sealing artesian
				  wells. Others feel that it may, under some conditions, eventually be carried
				  away into the surrounding formations.
Clay in a relatively dry state, clay and sand, or sand alone
				  may be used advantageously as sealing materials, particularly under water-table
				  conditions where diameters are large, depths are great, formations are caving,
				  and there is no need for achieving penetration of openings in casings, liners,
				  or formations, or for obtaining a watertight seal at any given spot.
Frequently combinations of these materials are necessary.
				  The more expensive materials are used when strength, penetration, or
				  watertightness are needed. The less expensive materials are used for the
				  remainder of the well. Cement grout or neat cement is now being mixed with
				  bentonite clays and various aggregates. Superior results and lower cost are
				  claimed for such mixtures.
ASTM STANDARD A 53*
Welded and Seamless Steel
Pipe Schedule 40 - Standard Weight
Nominal Size (Inches)
External Diameter (Inches)
Internal Diameter (Inches)
Weight Per Foot (lb)
Wall Thickness (Inches)
Plain End
Threads and Couplings
1 1/4
1.660
1.380
0.140
2.27
2.28
1 1/2
1.900
1.610
0.145
2.72
2.73
2
2.375
2.067
0.154
3.65
3.68
2 1/2
2.875
2.469
0.203
5.79
5.82
3
3.500
3.068
0.216
7.58
7.62
3 1/2
4.000
3.568
0.226
9.11
9.20
4
4.500
4.026
0.237
10.79
10.89
5
5.563
5.047
0.258
14.62
14.81
6
6.625
6.065
0.280
18.97
19.18
8
8.625
7.981
0.322
28.55
29.35
1 0
10.750
1 0.020
0.365
40.48
41.85
1 2
12.750
1 2.000
0.375
49.56
51.15
1 4
14.000
1 3.250
0.375
54.57
57.00
1 6
16.000
1 5.250
0.375
62.58
65.30
1 8
18.000
1 7.250
0.375
70.59
73.00
2 0
20.000
1 9.250
0.375
78.60
81.00
2 2
22.000
2 1.000
0.500
114.81
2 4
24.000
2 3.000
0.500
1 25.49
2 6
26.000
2 5.000
0.500
1 36.17
2 8
28.000
2 7.000
0.500
1 46.85
3 0
30.000
2 9.000
0.500
1 57.53
3 2
32.000
3 1.000
0.500
1 68.21
3 4
34.000
3 3.000
0.500
1 78.89
3 6
36.000
3 5.000
0.500
1 89.57
ASTM STANDARD A 589*
Water-Well Reamed and Drifted Pipe
Nominal Size (Inches)
External Diameter (Inches)
Internal Diameter (Inches)
Weight Per Foot (lb)
Wall Thickness (Inches)
Plain End
Threads and Couplings
1 1/4
1.660
1.380
0.140
2.27
2.30
1 1/2
1.900
1.610
0.145
2.72
2.75
2
2.375
2.067
0.154
3.65
3.75
2 1/2
2.875
2.469
0.203
5.79
5.90
3
3.500
3.068
0.216
7.58
7.70
3 1/2
4.000
3.548
0.226
9.11
9.25
4
4.500
4.026
0.237
10.79
1 1.00
5
5.563
5.047
0.258
14.62
15.00
6
6.625
6.065
0.280
18.97
19.45
8
8.625
7.981
0.322
28.55
29.35
1 0
10.750
1 0.020
0.365
40.48
41.85
1 2
12.750
1 2.000
0.375
49.56
51.15
*From "1973 Annual Book of ASTM Standards"
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