5.1.1 General. In establishing the location of a well, the constructor shall consider sources of contamination which exist on or adjacent to the premises where the well is to be located. As far as possible, the well shall be located on ground which is higher than sources of contamination and shall have ready access for repairs, maintenance, treatment and inspection.

5.1.2 Relation to sources of contamination. Determination of minimum lateral distances to locate a well from potential sources of contamination involves evaluation of the character and location of the sources of contamination, types of geologic formations present, depth to the aquifer, effect on ground water movement by well pumping and possibilities of flooding of the site by surface waters. Based on practice and experience, accepted minimum lateral distances for some common sources of pollution with respect to a well have been established. The lack of specific distances for other possible sources of contamination such as streams, refuse disposal sites, excavations, waste treatment facilities, buried oil and gasoline storage tanks, improperly constructed wells and cisterns, etc. does not minimize their potential hazard. These must be evaluated in each situation and a distance arrived at based on the pertinent facts.

5.1.3 Minimum lateral distances. The following minimum lateral distances shall apply for common sources of contamination listed:

When the upper formations are more pervious, the lateral distances shall be increased (i.e., double the distance for highly pervious gravel formations).

5.1.4 Flood water. Locations subject to flooding should be avoided. If no reasonable alternate site exists, wells may be constructed in flood zones providing special protective construction is included.

5.1.5 Vertical closed loop systems / wells. Vertical closed loop systems and wells shall not be located closer than fifty (50) feet to a septic tank, its field lines, or other water supply wells used for human consumption. This requirement may be waived. An approved waiver may be requested by contacting the Commission office by telephone or mail. Written approval must be obtained from the Commission prior to construction of the well.

5.1.6 Open loop systems / wells. The location of open loop wells shall meet the same criteria as water wells used for domestic or human consumption.

5.1.7 Industrial and irrigation wells. No industrial or irrigation well shall be located nearer than one hundred (100) feet to any other well producing potable water. It is recommended that locations subject to flooding be avoided. If no reasonable alternate exists, wells should be constructed with the casing terminating two (2) feet above the maximum known flood water elevation.

5.1.8 Relations to buildings. With respect to buildings, the location of a well shall be as follows:

5.1.8.1 Adjacent to building. When a well must be located adjacent to a building, it shall be located so that the center line of the well extended vertically will clear any projection from the building by not less than ten (10) feet. The well shall also be located at least ten (10) feet away from any power lines.

5.1.8.2 Inside building. The casing top of a well and any other opening shall not terminate in the basement of any building, or in any pit, room or space which is below ground surface or connected to a basement, which is not properly drained or pumped. Where it is necessary to seal out seep water or rain water in small diameter wells that are underground, National Water Well Association approved pitless adapters, or an approved seal, shall be used.

5.2.1 Natural protection. Location of the well shall include utilization of every natural protection available to promote sanitary conditions.

5.2.2 Undesirable geological formations. The exclusions of water bearing formations which are or may become contaminated formations which have undesirable characteristics.

5.2.3 Durability. The use of construction methods and materials which will result in a durable well producing safe water, without excessive sediment and sand, or harmful bacteria.

5.3.1 Construction water. Water used in the drilling process should be obtained from a source which will not result in contamination of the well. It is required that an appropriate amount of chlorine solution be added to the construction water in order to protect the well from contamination. Please refer to the tables in Section 11 to determine the proper amount of chlorine to use.

5.3.2 Plumbness and alignment. Each drilled well shall be tested for plumbness and alignment and the bore of the hole shall be sufficiently plumb and straight to receive the casing without binding. The casing shall be sufficiently plumb and straight so that it will not interfere with installation and operation of the pump.

5.3.3 Yield. Each well shall be tested for yield and draw down by pump, bailer, or air.

5.4.1 Temporary (outer) casing. Casing intended for construction purposes only shall be of weight and design as necessary to be watertight and permit installation without distortion or rupture to the specified depth.

5.4.2 Grouting guides. Protective casing that is to be grouted in the drill hole should have sufficient guides welded to the casing to permit the unobstructed flow and disposition of the thickness of grout specified.

5.4.3 Screens. Screen openings shall provide the maximum amount of open area consistent with the strength of screen and the grading of the water bearing formation or gravel pack. The opening shall permit maximum transmitting ability without clogging or jamming.

5.4.4 Joints. All casing pipe joints shall be watertight welded construction or threaded couplings.

5.4.5 Upper terminal. The casing, well curb or riser pipe shall be terminated at a height above ground surface consistent with the proposed plans for a pump house and pump installation but not less than eight (8) inches above ground surface or twenty-four (24) inches above maximum high-water level where flooding occurs.

5.4.6 Steel casing for domestic, individual, and stock wells. Casing for domestic, individual and stock wells of steel construction shall be as follows: Minimum eleven (11) pound black steel pipe may be used in consolidated formations. ASA Galvanized Standard Weight Schedule 40 pipe, one (1) inch I.D. to four (4) inches I.D. pipe size and weight are covered in Rule 11. 4.090-inch I. D. galvanized pipe, 9-1/2 pound (schedule 30) may be used on a statewide basis with the following provision that any failure of this weight pipe within a five (5) year period be replaced by the contractor at no cost to the landowner.

5.4.7 PVC casing. Effective January 1, 1989, PVC plastic casing may be used provided the PVC pipe is manufactured as water well casing and is permanently marked as well casing. The casing shall be made to ASTM F480. The Contractor shall be responsible to assure that the PVC wall thickness shall be sufficient to withstand both the formation and hydrostatic pressures imposed on the casing during its installation and development. PVC casing shall be used only when construction practices will allow the bore hole to remain open during casing installation and the casing can be lowered freely without driving.

5.4.8 Fiberglass casing. Fiberglass reinforced plastic well casing, tested in accordance with ASTM D1180 (American Society Testing Materials), may be used where judged desirable by the contractor and approved by the customer, in consolidated and unconsolidated formations. Each coupling shall form a watertight seal. Pipe having a minimum bursting pressure of 660 PSI may be used.

5.4.9.1 General. All casing, including steel shall be strong enough to resist the forces imposed during installation and other forces that can be expected after installation. It shall be the contractor's responsibility to see that all casing used in industrial and irrigation wells will not collapse. Any material used in construction of industrial and irrigation wells that collapses or breaks within (5) five years shall be renewed with a material strong enough to withstand the stress or pressure without charge to the customer.

5.4.9.2 PVC casing. PVC 160 PSI NSF or stronger material classification may be used in construction of industrial and irrigation wells, where judged desirable by the contractor and approved by the customer in unconsolidated formations. All pipes shall be permanently marked under a method suitable to the National Sanitation Foundation. Plastic pipe must be made of new, not reclaimed material.

5.4.9.3 Joints. The joints of all casing shall be watertight and plumb and in alignment. All casing shall be installed to seal off water bearing formations that contain undesirable water (such as saline) and prevent water from the surface entering the fresh water aquifer so as not to contaminate them. Each joint of PVC pipe shall have a minimum of four (4) screws or rivets in the coupling.

5.4.10 Casing in consolidated formations. Metal or plastic casing shall extend a minimum of one (1) foot into solid bedrock or slate in a cement or Bentonite seal at least one (1) inch thick from rock upward for five (5) feet. In wells where consolidated formations, such as bedrock or slate, occur as a definable unit, the casing shall be set into the consolidated formation and sealed below all crevices that would normally release water of inferior quality into the well. Plastic casing may be used to case through overburden in consolidated formations, providing the casing meets the requirements for the depth being cased.

5.4.10.1 Rock below creviced formation. The diameter of the drill hole through the creviced formation shall be a minimum of two (2) inches greater than the diameter of the casing. If an outer casing is left in place in the earth mantle, the annular opening around that casing shall be sealed as outlined in Rule 5.4.11. All wells constructed in consolidated formations shall be cased a minimum of ten (10) feet from ground surface or one (1) foot minimum into the consolidated formation. [FN1] All casing left permanently installed in consolidated formations shall be grouted with the appropriate materials, as outlined in Rule 5.5, from the bottom of the casing upward five (5) feet. Where a desirable water bearing formation underlies a crevice or undesirable water bearing formation, the overlaying formation should be completely grout sealed and watertight. Drilling construction should extend into the desired formation.

5.4.11 Casing in unconsolidated formations. Unconsolidated formations such as sand and gravel may extend to or near the ground surface. Generally, however, they lie below the ground surface at varying depths and are covered by an over burden of earth. The kind, nature and depth of the over burden are factors in determining how a well shall be constructed. Wells constructed in unconsolidated formations shall have a permanent casing installed, in which the casing or screen shall extend the complete length of the drill hole. A minimum of the upper ten (10) feet shall be filled with grout after the casing is in place.

5.4.11.1 Gravel wall construction. When an oversized drill hole is constructed to permit the placement of a gravel wall around the well screen or perforated casing, the annular opening between the casing and the drill hole shall be sealed in the top twenty (20) feet with concrete, cement, or Bentonite grout. If a permanent outer casing is installed, it shall extend to a depth of at least twenty (20) feet depending on the formations present, the annular opening between the drill hole and the outer casing shall be sealed as provided for in Rule 5.4.12. The annular opening between inner and outer casings shall be filled with concrete, cement, or Bentonite grout in the upper twenty (20) feet.

5.5.1 Sand and cement grout. This mixture should consist of cement, sand and water, in the proportion of one bag of cement (94 pounds) and an equal volume of dry sand to not more than six (6) gallons of clean water.

5.5.2 Neat cement grout. This mixture should consist of one bag of cement (94 pounds) to not more than six (6) gallons of clean water. Additives up to 6% by weight to increase fluidity may be used.

5.5.3 Concrete. This mixture should consist of cement, sand, aggregate (gravel), and water in the proportion of one bag of cement (94 pounds) and an equal amount of dry sand and aggregate and clean water. Concrete can be used in the top ten (10) feet of the annular space around the casing of the large diameter wells when the annular space is larger than two (2) inches from the outside of the casing wall to the face of the bore hole. Aggregate shall be no larger than 1/5 of the dimension between the outside casing and the face of the bore hole. All concrete shall be placed to prevent voids.

5.5.4 Bentonite grout. Bentonite or sealing clay grout is a manufactured clay product that expands in contact with moisture to form a seal that prevents the movement of water and may be used in consolidated and unconsolidated formations. It is the responsibility of the contractor to make the viscosity of the bentonite thick enough to seal out all contaminates.

5.5.5 Grouting of metal-cased wells. Metal casing shall be encased in a cement seal at least two (2) inches thick from ground level to a distance of at least ten (10) feet below established ground surface.

5.5.6 Grouting of curbed wells. Curbed wells shall be concreted at least six (6) inches thick poured monolithically from the upper terminal to a distance of at least ten feet below established ground surface.

5.6.1 General. Well seals or caps installed on wells shall be securely capped. The seal may provide ventilation but shall be sufficiently tight and secure to prohibit foreign objects, insects and other creatures from entering the well. The well seal shall be secure to prohibit entrance to the well from unauthorized persons without tools or excessive physical exertion.

5.6.2 Timing. The well seal or cap shall be installed immediately upon completion of the well and prior to departure of the driller and or contractor or his drilling equipment from the well site. An effort should be made by the driller or contractor to ensure that the well seal or cap provided/installed is compatible to the type of pump and pipe to be installed.

5.6.3 Seals or caps when pump installed. Well seals or caps shall be installed on all water wells after pump installation and shall be securely capped. The seal MAY provide ventilation but be sufficiently tight and secure to prohibit foreign objects, contamination, insects and other pests from entering the well. The well seal shall be secure to prohibit entrance to the well from unauthorized persons without tools or excessive physical exertion. All wells in consolidated areas will be vented with insect proof vents. If the well is located inside a building it shall be vented to the outside.

5.6.4 Pitless adapters. Pitless adapters shall be installed in a manner that excludes entrance of water or other materials into the well.

5.6.5 Test holes. The contractor shall insure that the well/hole is capped to prevent injury or pollution. If the test well is abandoned, then the well shall be plugged as outlined in Rule 5.8.

5.7.1 General. Every new well, or existing water supply system that has been disrupted for service or repair, should be disinfected before it is returned to use. Water in the well and storage tank should be treated with a strong chlorine solution to destroy disease organisms. All pipe lines and fixtures in the distribution system should be rinsed and flushed with chlorinated water. All wells, excluding irrigation, will be disinfected.

5.7.2 Timing. If the constructor of the well is also responsible for preparing the well for the pump installation and making the pump installations, disinfection may be postponed until his work is completed. In the event the constructor does not have this responsibility, it is required before capping the well that an appropriate amount of chlorine solution be introduced into the well.

5.7.3 Disinfection and pump installation. At the time of new pump installation or reinstallation of an existing pump, the water system shall be chlorinated to a minimum concentration of 50 ppm for a minimum of 24 hours. Each well shall be disinfected by tablets and/or liquid.

5.7.4 Water. Water, which has contacted pipe or equipment used in chemigation, shall not be allowed to back siphon or be used to backwash the well.

5.7.5 Emergencies. If an emergency exists, the water system may be used, provided, the system is not for human consumption, and the system is disinfected as soon as the situation permits. Refer to the tables in Section 11 for guidance on administering chlorine.

5.8.1 General. To restore geologic and hydrogeologic conditions existing prior to a well's construction, any person who abandons an abandoned well, as defined in Rule 10.28, must use methods and materials that will protect the ground water from surface contamination and prohibit cross-contamination (co-mingling) of aquifers. Clay, cement, or bentonite will be allowed to plug wells with certain restrictions applied when using bentonite.

5.8.2 Dry holes. If no water is encountered and the landowner does not wish to abandon the well in the event that he might plan further development of the well at a later date, the contractor shall complete the well according to the rules, including casing, sealing, and capping the well.

5.8.3 File well abandonment form. All wells plugged in the State should be reported by the water well contractor to the AWWCC on a well abandonment form to be approved by the AWWCC within ninety (90) days of abandonment.