Section 0400-45-09-.10 - WELL CONSTRUCTION STANDARDSThese rules will apply solely to wells constructed for the production of water from underground sources and have no application to wells constructed for quarry blast holes or mineral prospecting, or any purpose other than production of water.
(1) Requirements (a) No person shall construct, reconstruct, or repair, or cause to be constructed or reconstructed or repaired any water well; nor shall any person install, repair, or cause to be installed or repaired any pump, pumping equipment, water filter or water treatment device to be used on a water well except in accordance with the provisions of the Wells Act (T.C.A. §§ 69-10-101 et seq.) and these rules.(b) Every well driller, within sixty (60) days after completion of a water well, shall submit a report on the construction or reconstruction of the well to the Department. The well completion report shall be made on a form provided by the Department or a reasonable facsimile approved by the Department.(c) A Notice of Intent to drill a water well must be submitted by the property owner or the licensed well driller to the Director in the manner prescribed by the Department, prior to commencement of drilling a water well in Tennessee. The licensed driller is required to have sufficient documentation that a Notice of Intent was submitted to the Division of Water Resources before beginning operations at a drill site. Sufficient documentation for a Notice of Intent being filed may include one of the following:1. Fee receipt of the Notice of Intent.2. Confirmation number of the Notice of Intent or other approved format approved by the Director and issued by the Department.(d) The Notice of Intent fee or copy of the receipt for a Notice of Intent fee shall accompany the submission of the driller's report. No well or borehole shall be drilled unless the driller has documentation that a Notice of Intent has been filed. All well reports shall be submitted with documentation of the Notice of Intent fee being paid. Documentation of the fee being paid shall consist of the receipt originating from a Notice of Intent or money collected and enclosed with the original driller's report by the driller for the Notice of Intent. A Notice of Intent and fee is not required for well closure, deepening or reworking any water well or closed loop geothermal borehole. The amount of the Notice of Intent fee shall be reviewed by the Department at least every five (5) years and shall currently be scheduled as follows:1. Water wells for production of water per property site $75(e) The requirement to furnish the Department a Notice of Intent fee payment shall not apply to water wells drilled in any local jurisdiction which is authorized, by private act or pursuant to the provisions of an adopted "home rule" charter, to regulate the location and construction of these wells and which has established a fee for the inspection of both geothermal and water wells approved by the Commissioner.(f) A Notice of Intent fee shall not apply to any property owner, who within the past five years has filed a notice of intent and paid the fee for the same property. The property owner or driller must identify on the new Notice of Intent submitted for the property the identification number from the first Notice of Intent fee submitted.(g) Checks returned for insufficient funds will be charged an established check processing fee and the Division will seek payment from the individual responsible for writing the check.(h) A Notice of Intent shall expire one hundred and eighty days from the original date filed by the well driller or homeowner.(i) When strict compliance with these standards is impractical, the driller or installer shall make application to the Department for approval of an alternative standard prior to the work being done. The Department may grant the request for an alternative standard if it determines the proposed standards offer an equivalent or higher level of protection to the environment. In an emergency or in exceptional instances, the Department will respond to a verbal request provided the applicant submits a written application within ten (10) days of the verbal application.(j) Every well driller or person holding a well closure license, within sixty (60) days of abandonment of a water well, shall submit a report of the abandonment of the well or borehole to the Department. The abandonment report shall be made on a form provided by the Department or a reasonable facsimile approved by the Department. The report shall include the same information as required on the completion report and shall include specific information on how the well was closed and the placement and type of backfill placed in the well bore. The abandonment report shall be signed by the licensed driller or person holding a well closure license. All well closure reports shall include a diagram showing the location and distance in feet of the closed well from one specific landmark and septic system or sewer systems on the property.(2) Location (a) The construction of a water well is prohibited at other than a safe distance from any known potential source of contamination. The minimum safe distances shown in Table A shall apply for the sources of contamination listed therein.(b) A water supply well may be constructed in an area subject to flooding provided the top of the water tight casing extends not less than two (2) feet above the one hundred (100) year flood plain.(c) Relation to buildings, pits, and basements:1. A well located adjacent to a building shall be so located that the center line of the well extended vertically will clear any projection from the building by not less than five (5) feet.2. New wells shall not be constructed in pits or basements.(d) New wells shall not be located closer than ten (10) feet from a property line. New wells located from ten (10) feet to twenty-five (25) feet from a property line shall require a minimum of thirty-five (35) feet of casing installed below land surface with impervious material such as cement grout or bentonite chips, tablets or bentonite grout backfilled in the annular space to a depth of thirty-five feet. TABLE A
MINIMUM DISTANCES TO SEPARATE WATER WELLS FROM POTENTIAL SOURCES OF CONTAMINATION
SOURCES OF CONTAMINATION | MINIMUM DISTANCES |
Animal pens or feed lots | 100 feet |
Leaching Pits; sewage lagoons | 200 feet |
Pit Privys | 75 feet |
Sewer lines | 50 feet |
Sludge and septage disposal sites | 100 feet |
Septic tanks and drain fields | 50 feet |
House to septic tank connections, if the line is tight | 10 feet |
House to sewer line, if the line is tight | 10 feet |
(3) Source of Water Supply (a) The source of water for any well shall be at least nineteen (19) feet below the surface of the ground. 1. In the event that no other ground water source is available, a source of less than nineteen (19) feet deep may be developed provided that:(i) Prior to the installation of the casing in the well, the Division of Water Resources Central Office is notified by phone regarding:(I) County and street address of the well(II) Name and phone number of the well owner(III) Street address of owner if different from address of the well(ii) A minimum of ten (10) feet of casing is installed below ground surface.(iii) The well is sealed from land surface to a minimum ten (10) feet below ground with either cement grout or bentonite.(iv) The owner of the well is advised by the driller concerning the development of a water bearing zone less than nineteen (19) feet deep by sending a written report to the homeowner and to the Division, at the time the completion report is submitted, containing the following advisory:(I) The owner may need to place a chlorinator on the well to treat the water for potential problems with microbiological contamination.(II) A shallow water bearing zone may be more subject to surface contamination surrounding the well and the well yield may diminish over time.(III) The homeowner should provide a copy of the report and disclaimer to any prospective buyer prior to any resale of the property where the well is located.(b) The driller shall develop the most favorable water-bearing zone(s) and seal off any source(s) of less desirable quality.(c) It shall be the duty of any person attempting to construct a water well to seal off salt water, oil, gas, or any other fluid or material which might contaminate a source of fresh water.(4) Drilling Fluids for Water Wells(a) Water used during the construction of a water well shall be obtained from a public water supply, water well or protected spring box. Water taken from ponds, lakes, streams or other surface sources shall not be used.(b) All water used shall also be treated with enough liquid bleach or hypochlorite granules to retain a free chlorine residual of at least two (2) parts per million.(c) The driller shall denote on the water well report submitted to the Department from what source his drilling process water was obtained.(d) Drilling fluids and additives shall be materials specified by the manufacturer for use in water well construction and approved by the Department.(e) During the course of drilling a water well with air rotary equipment, a minimum of one (1) gallon of water per minute must be injected or added into the air stream. The amount of water injected shall be sufficient to control dust and to keep the hole cleaned out.(f) The amount of rock drill oil used to lubricate down hole drilling hammers shall not exceed hammer manufacturer's recommendations. The oil used to lubricate the hammer shall be specifically designed for that purpose.(g) Petroleum based products or byproducts spilled or leaked from a drill rig or pump truck in any quantity greater than one (1) quart shall be removed from the area within a twenty-five (25) foot radius around the well by the driller or installer responsible for the spill before the drill rig or pump truck leaves the site.(5) Casing (a) Wells drilled for the production of water shall be cased with watertight casing extending from at least nineteen (19) feet below the land surface to a minimum of six (6) inches above land surface. For wells located in areas subject to flooding, see subparagraph (2)(b) of this rule. For water sources less than nineteen (19) feet deep see subparagraph (3)(a) of this rule.1. The watertight casing in wells constructed to obtain water from a consolidated rock formation shall be firmly seated and sealed below all crevices that release inferior quality water or mud into the well or to a depth of at least five (5) feet below the top of the consolidated rock whichever is greater.2. The watertight casing in wells constructed to produce water from an unconsolidated aquifer (such as saturated gravel or sand) shall extend at least to the top of the aquifer or to a depth of nineteen (19) feet which ever is greater.(b) Except as otherwise specified in these regulations, the permanent well casing shall: 1. Casing shall be new or in like new condition. Such casing or pipe shall not be used unless free of leaks, corrosion, and dents; is straight and true, and not out of round, seamless or welded, black or galvanized steel pipe conforming to the weights and dimensions given in Table B and meeting the American Society for Testing and Materials (ASTM) Standards A53-87b or A589-85. Reject pipe shall not be used;2. Have watertight joints that may be welded, or threaded and coupled; and3. Be equipped with a drive shoe if the casing is to be driven.4. Pipe sizes that are not listed in Table B and are less than ten (10) inches in diameter shall match listed values as closely as possible.5. Pipe sizes that are ten (10) inches in diameter or larger shall be Schedule 20 pipe as a minimum. TABLE B
MINIMUM DIMENSIONS AND WEIGHTS FOR WATER WELL CASING
Diameters in inches | Minimum Wall Thickness in Inches | Weight in Pounds per foot |
External | Internal | in Inches | Plain Ends Only |
3.500 | 3.250 | 0.125 | 4.51 |
4.000 | 3.732 | 0.134 | 5.53 |
4.500 | 4.216 | 0.142 | 6.61 |
5.500 | 5.192 | 0.154 | 8.79 |
6.000 | 5.672 | 0.164 | 10.22 |
6.625 | 6.255 | 0.185 | 12.72 |
8.625 | 8.249 | 0.188 | 16.90 |
(c) Thermoplastic well casing may be installed in wells constructed to obtain water from unconsolidated aquifers (such as saturated gravel, sand or overburden) provided: 2. The casting meets or exceeds the requirements of ASTM Standard F-480-88 and bears the NSF (National Sanitation Foundation) seal in each section of casing;3. The Standard Dimension Ratio (SDR) shall not exceed 26;4. The casing is installed after the borehole has been drilled to the final depth of the finished well, and no additional drilling takes place after the casing has been installed; and5. Joints shall be solvent cemented with a quick-setting cement, or threaded and coupled.(d) In areas where the water is obtained from overburden above the consolidated rock surface, the casing shall be set at or just above the consolidated rock. A screen may be attached to the bottom of the casing or the lowermost few feet of the casing may be slotted or perforated to allow water to enter the well provided the top of the screen or the topmost perforation in the casing is at least 20 feet below land surface. The completed well shall be finished so that extraneous material such as sediment cannot enter the well.(e) Water well casing shall extend a minimum of six inches above the finished land surface unless, site conditions dictate that the well head will be better protected below ground surface and the upper terminus is constructed in the following manner: 1. The casing is terminated just below ground surface in a watertight manhole cover.2. The manhole cover lid and skirt shall be all cast steel or aluminum construction.3. The manhole cover shall have a sufficient diameter to use a well cap below the manhole lid.4. The manhole shall be secured by a concrete pad two inches thick and no less than 24 inches in diameter.5. The manhole cover shall be equipped with a positive drain to an area where water cannot enter from flooding or where excessive runoff could back up through the drain to the well head. The drain may be located in the basement area of a house.6. The manhole cover shall be clearly marked on the cover as a "water well".7. Construction techniques for casings cut off below ground level shall conform to the drawing in figure 1. BELOW GROUND SURFACE W ELL HEAD CONSTRUCTION
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Figure 1
(f) The upper terminus of the well head shall be capped with a watertight well seal or cap specifically designed for capping the well.(6) Backfilling and Grouting(a) The grout material used in the backfilling or grouting of a water well shall consist of a mixture of Portland Class A cement or quick setting cement in a ratio of not over six (6.0) gallons of water per ninety-four (94) pound sack of cement, or a high solids mixing bentonite grout with a minimum of 20% solids and a weight of no less than nine and two tenths (9.2) pounds per gallon as measured by a standard mud balance. The use of bentonite, in chip or tablet form, ranging in size from one-quarter inch (1/4) to three-quarters of an inch (3/4) will be allowed as an alternate seal to slurry grouting. The bentonite shall be mixed and applied in accordance with the manufacturer's recommendations. The use of low solids bentonite drilling clay designed for use as a drilling fluid to form a filter cake on the side walls of the borehole and to increase viscosity of water) is prohibited for use as a grout or sealing material except as an additive. Only bentonite grout, bentonite tablets, or bentonite chips approved by the National Sanitation Foundation (NSF) or American National Standards Institute (ANSI) certified parties as meeting NSF product standard 60 or 61 shall be approved by the Department as appropriate grouting or sealing material.(b) For wells completed with either steel or plastic well casing, the annular space between the casing and borehole wall of the well from a depth of three (3) feet to ten (10) feet below land surface shall be backfilled with an impervious material of either cement grout or bentonite as defined in subparagraph (a) of this paragraph. The remaining annular space between the casing and borehole wall shall be backfilled with an impervious material or combination of materials such as cement, bentonite, sand , puddled clay or well cuttings. However, the department recommends that the remaining annular space between the casing and the borehole wall of the well to the bottom of the watertight casing, be filled with the same grout or sealing material used from three to ten feet.(c) Placement of the backfill material shall be done in such a way that there are no bridges or gaps in the annulus. The top of the backfill material shall remain level with the land surface surrounding the well.(d) If bentonite is used for backfill, it shall be placed in accordance with the manufacturer's recommendations. For example, the product "Holeplug" from Baroid requires the annular space in a well to be one and one half inches (1-1/2") in clearance or more when "Holeplug" three fourths inch (3/4") is used. The annular space must be a minimum of three fourths inch (3/4") in clearance in the event that "Holeplug" three eighths inch (3/8") bentonite is used.(e) If cement based grout or bentonite based grout is used for backfill, it shall be placed around the casing by one of the following methods:1. Pressure The annular space between the casing and the borehole wall shall be a minimum of one and five-tenths (1.5) inches, and grout shall be pumped or forced under pressure through the bottom of the casing until it fills the annular space around the casing and overflows at the surface; or
2. Pumping The annular space between the casing and formation shall be a minimum of one and five tenths (1.5) inches and grout shall be pumped into place through a pipe or hose extended to the bottom of the annular space which can be raised as the grout is applied, but the grout pipe or hose shall remain submerged in grout during the entire application; or
3. Other The annular space between the casing and the borehole wall shall be a minimum of two (2) inches and the annular space shall be completely filled with grout by any method that will insure complete filling of the space, provided the annular area does not contain water or other fluid. If the annular area contains water or other fluid, it shall be evacuated of fluid or the grout shall be placed by the pumping or pressure method.
(7) Well Screens (a) Any water well finished in an unconsolidated rock formation shall be equipped with a screen or perforated pipe that will adequately prevent the entrance of soil or formation material into the well after the well has been developed and completed by the well contractor.(b) The well screen shall:1. Be of steel, stainless steel, plastic or other Department approved material and shall be of a strength to satisfactorily withstand chemical and physical forces applied to it during and after installation;2. Be of a design to permit optimum development of the aquifer with minimum head loss consistent with the intended use of the well;3. Have openings designed to prevent clogging and shall be free of rough edges, irregularities or other defects that may accelerate or contribute to corrosion or clogging; and4. Be provided with such fittings as are necessary to seal the top of the screen to the watertight casing and to close the bottom. If the screen is installed through the casing, a packer, seal or other approved design shall be used to prevent the entry of ground water into the well through any openings other than the screen.(c) Multi-screened wells shall not connect aquifers or zones which have differences in: 1. Water quality to the extent that intermixing of the waters would result in deterioration of the water quality in any aquifer or zone.2. Static water levels that would result in depletion of water from any aquifer or zone, or significant loss of head in any aquifer or zone.(8) Gravel-Packed Wells (a) In constructing a gravel-packed well: 1. The gravel shall be composed of quartz, granite, or similar rock material and shall be clean, rounded, uniform, water-washed and free from clay, silt, or other deleterious material.2. The gravel shall be placed in the annular space around the screens and casing by any method that will insure accurate placement and avoid bridging or segregation.3. The gravel pack shall have a minimum thickness of at least one-inch and shall be placed a minimum of nineteen feet below land surface.4. The gravel shall be disinfected using water with a free chlorine residual of at least 50 parts per million (ppm).(b) The gravel pack shall not connect aquifers or zones which have differences:1. In water quality that would result in deterioration of the water quality in any aquifer or zone.2. In static water levels that would result in depletion of water from any aquifer or significant loss of head in any aquifer or zone.(9) Large Diameter Wells (a) Large-diameter bored or augered wells may be cased with concrete pipe provided such wells are constructed as follows: 1. The bore hole shall have a minimum diameter of six (6) inches larger than the outside diameter of the casing.2. The annular space around the casing shall be filled with grout to a depth at least five feet below the static water level or twenty (20) feet below land surface, whichever is greater. The grout shall be placed in accordance with the requirements of subparagraph (6)(d) of Rule 0400-45-09-.10.3. The annular space around the casing below the grout shall be completely filled with sand or gravel that has been disinfected with water containing a free-chlorine residual of at least 50 parts per million (ppm).4. The sand or gravel material shall be composed of quartz, granite, or similar rock material and shall be clean, rounded, uniform, water-washed and free from clay, silt, or other deleterious material.(b) The wellhead shall be completed in the same manner as required for other water-supply wells.(10) Well Development. Prior to completion of a well for water supply, the driller shall take all steps necessary to: (a) Remove any mud, drill cuttings, or other foreign matter from the well that would render the well useless for its intended purpose;(b) Correct any damage to the aquifer that might have occurred during drilling; and(d) Fracturing as an aid in water well development:1. Fracturing includes the use of explosives, acid or pumping fluids or air into water well in an attempt to increase the yield of the well. General water well disinfection procedure with chlorine is not considered fracturing. A licensed driller shall supervise fracturing and submit a rework report for each site.2. Water used in fracturing must be obtained from a public water supply, water well or protected springbox and chlorinated a minimum of two (2) parts per million chlorine residual prior to injection.3. Wells located closer than fifty (50) feet from known sources of pollution shall not be fractured. Known sources of pollution include but are not limited to septic tanks field lines and sewers.4. All packers set in a zone to be fractured by fluid or air must be placed at depths greater than fifty feet below land surface or a depth greater than twenty feet below the bottom of water tight casing, or whichever is greater in depth from land surface.5. The driller shall submit a report of driller within sixty (60) days upon completion of fracturing the well reworking the well, and denote in the comments section the zone fractured, water used and amount of pressure induced on each zone.(11) Wellhead Completion(a) The top of the casing shall be cut off smooth and level, be free from dents and cracks, and shall terminate at least six (6) inches above the land surface. All wells shall be capped with an approved well cap.(b) Underground installations leading from the well shall employ a pitless adapter which does not require welding at the casing. Pitless units or adapters shall comply with the Water Systems Council's Pitless Adapter Division (PAD) PAS-1 (6th Ed., March 1987) and shall bear the PAD symbol of certification or shall otherwise have been approved by the Department.(c) Pitless units or adapters shall be constructed and installed so as to prevent the entrance of contaminants into the well or potable water supply, conduct water from the well, protect the water from freezing, and provide access to water system parts within the well.(d) Surface drainage shall be diverted away from the well head so that water is not allowed to stand around the casing.Tenn. Comp. R. & Regs. 0400-45-09-.10
Original rule filed October 16, 2012; effective January 14, 2013. Rule renumbered from 1200-04-09. Amendment filed June 19, 2015; effective 9/17/2015.Authority: T.C.A. §§ 69-10-101 et seq. and 4-5-201 et seq.