NR 811.12(12)(f)(f) Following completion of the chemical conditioning procedure, the well shall be thoroughly disinfected with chlorine only. Acids for pH control may only be used when the acid does not include additives or the only additives used are intended to mitigate corrosion of metal surfaces. Following disinfection, the well shall be pumped to waste and safe bacteriological water samples shall be collected according to the requirements under s. NR 810.09 (4).

NR 811.12(12)(g)(g) The owner or an authorized representative shall submit a written report to the department within 30 days of the date of completion of the chemical conditioning and subsequent pumping of the well that includes the static and pumping water levels, gallon per minute pumping rate and specific capacity of the well both before and after chemical conditioning, and the results of any testing for chemical or physical properties for which the well may have been chemically conditioned, if applicable.

NR 811.12(12)(i)(i) The department may require additional water quality sampling following a well rehabilitation based on well raw water quality and the rehabilitation methods used to verify water quality and to protect water consumers.

NR 811.12(13)(13) Other methods of well reconditioning. Approval shall be obtained from the department prior to performing any other type of reconditioning procedure, including hydrofracturing and impulse generation techniques. The requester shall submit written information regarding the procedure, the equipment, materials, chemicals, pressures to be used, and the disposal of waste to the department for approval. Reconditioning procedures under this subsection are subject to all of the following requirements:

NR 811.12(13)(a)1.1. The department’s regional drinking water staff person shall be given at least 48 hours notice prior to the date and time of the proposed hydrofracturing work.

NR 811.12(13)(a)2.2. Hydrofracturing shall be performed by or under the supervision of a licensed well driller.

NR 811.12(13)(a)3.3. Clean washed inert, nontoxic material such as sand may be added to the water for the purpose of holding the joints and fractures open after the pressure is reduced.

NR 811.12(13)(a)4.4. When a well is to be hydrofractured within 100 feet of any existing bedrock well, the well driller shall notify the existing well owner or owners and the department’s regional drinking water staff person of the forthcoming hydrofracturing operation at least 48 hours prior to the commencement of the hydrofracturing operation.

NR 811.12(13)(a)5.5. The upper packer may not be placed at a depth closer than 20 feet below the bottom of the casing.

NR 811.12(13)(a)6.6. Following the completion of the hydrofracturing procedure, the well shall be thoroughly disinfected, pumped to waste, and safe bacteriological water samples shall be collected according to the requirements of s. NR 810.09 (4).

NR 811.12(13)(a)7.7. The owner or an authorized representative shall submit a written report to the department within 30 days of the date of completion of the hydrofracturing and subsequent pumping of the well that includes the static and pumping water levels, gallon per minute pumping rate and specific capacity of the well both before and after the hydrofracturing, and the results of any testing for chemical or physical properties for which the well may have been hydrofractured, if applicable.

NR 811.12(13)(a)8.8. All material released from the casings, screen, and borehole as part of the rehabilitation shall be removed from the well.

NR 811.12(13)(b)1.1. The department’s regional drinking water staff person shall be given at least 48 hours notice prior to the date and time of the impulse generation work.

NR 811.12(13)(b)2.2. Impulse generation procedures shall be performed by or under the supervision of a licensed well driller.

NR 811.12(13)(b)3.3. A report shall be submitted to the department that identifies the impulse method to be used, the means of generating the impulse, the number of passes, the depths in the open drillhole or well screen that the procedure will be started and stopped, the psi strength of each impulse, and the number of impulses per foot. The report shall also include information on all the gases to be used and details of any chemical addition to be performed along with the impulse generation procedures, including the chemicals to be used, the reason for using the chemicals, the strength of each chemical as applied, the means to be used to inject the chemicals, and how the chemicals will be neutralized and disposed of. All chemicals used shall have NSF/ANSI Standard 60 approved for use in potable water as required per s. NR 810.09 (1) (c).

NR 811.12(13)(b)4.4. Impulse strength shall be maintained low enough to prevent structural damage to well casings, grout, and screens.

NR 811.12(13)(b)5.5. Following the completion of the impulse generation work, the well shall be thoroughly disinfected, pumped to waste, and safe bacteriological water samples shall be collected according to the requirements of s. NR 810.09 (4).

NR 811.12(13)(b)6.6. The owner or an authorized representative shall submit a written report to the department within 30 days of the date of completion of the impulse generation and subsequent pumping of the well that includes the static and pumping water levels, gallon per minute pumping rate and specific capacity of the well both before and after the impulse generation, and the results of any testing for chemical or physical properties for which the well may have been treated with impulse generation, if applicable.

NR 811.12(13)(b)7.7. All material released from the casings, screen, and borehole as part of the rehabilitation shall be removed from the well.

NR 811.12(14)(14) Grouting requirements. The water system owner shall give notice to the department’s regional drinking water staff person at least 48 hours prior to the date and time of the well grouting work. In addition, all of the following requirements shall be met:

NR 811.12(14)(a)1.1. Neat cement grout shall be labeled as ASTM C150, Type I, ASTM C595, Type IL, or API-10A, Class A Portland cement and water from a known bacteriologically safe and uncontaminated source, with not more than 6 gallons of water per 94-pound sack of cement. A mud balance shall be used to measure the grout density. Additives, including bentonite to increase fluidity, reduce shrinkage, or control time of set may be used only with prior department approval. No more than 4.7 pounds of powdered bentonite, a maximum of 5 percent, may be added to each 94-pound sack of cement. When bentonite is added, the volume of water shall be increased. When bentonite is added, a pressurized mud balance shall be used to measure the grout density. Bentonite mixed with neat cement grout shall comply with Table 2.

NR 811.12(14)(a)2.2. Sand cement grout may be used for annular openings greater than 3 inches. The mixture may not exceed 2 parts by weight of sand to one part of ASTM C150, Type 1 or API-10A, Class A Portland cement and not more than 6 gallons of water from a known bacteriologically safe and uncontaminated source to each 94-pound sack of cement.

NR 811.12(14)(a)3.3. Concrete grout may be used for annular openings greater than 6 inches. The concrete shall contain not less than 6 sacks of cement per cubic yard and not more than 6 gallons of water from a known bacteriologically safe uncontaminated source to each 94-pound sack of cement. The gravel size may not exceed 0.75 inch. The volumetric ratio of either gravel or sand to cement may not exceed 2.5 parts to one part. Wisconsin department of transportation grade A concrete is also acceptable.