Chapter NR 812

NR 812.14(7)(b) (b) Sodium bentonite, sodium bentonite-sand, neat cement or bentonite-cement when the upper enlarged drillhole extends less than 5 feet into the top of bedrock.

NR 812.14(7)(c) (c) Neat cement or bentonite-cement when the upper enlarged drillhole extends 5 feet or more into the top of bedrock.

NR 812.14(8) (8) Bentonite chips in fractured formations. A well driller or well constructor may use bentonite chips in an annular space when fractures, voids, or caverns are encountered that prevent the flow of grout at the surface. When bentonite chips are used by a well driller or well constructor to seal fractures in an annular space, the chips shall be placed in accordance with all of the following:

NR 812.14(8)(a) (a) The upper enlarged drillhole shall be a minimum of 4 inches larger than the nominal diameter of the permanent casing and shall extend to the depth of any fractures, voids or caverns encountered greater than 20 feet below the ground surface.

NR 812.14(8)(b) (b) The upper enlarged drillhole shall be free of drilling mud or cuttings.

NR 812.14(8)(c) (c) Any bentonite chips placed below the water table shall be screened and poured in a manner that prevents bridging.

NR 812.14(8)(d) (d) Any bentonite chips placed above the water table shall be hydrated using water meeting the requirements specified in s. NR 812.11 (14).

NR 812.14(8)(e) (e) The volume of bentonite chips used shall be limited to the minimum needed to resume grouting according to the requirements specified in s. NR 812.20.

NR 812.14(8)(f) (f) The number of bags or volume of chips used, the depth they were placed, and the reason they were needed shall be noted on the well construction report.

NR 812.14(9) (9) Dual aquifer prohibition. Wells may not be constructed open to both an unconsolidated formation and a bedrock formation.

NR 812.14(10) (10) Wells constructed into the maquoketa shale. Wells constructed or reconstructed to withdraw water from any of the aquifers beneath the Maquoketa Shale and the Niagara formations in the eastern part of the state shall be cased and grouted into the Maquoketa Shale formation except in areas designated by the department as special well casing pipe depth areas. If a liner is used to case off the Niagara formation, the Maquoketa Shale formation or both, it shall be installed and grouted in place in accordance with s. NR 812.21.

NR 812.14 History History: CR 18-095: r. and recr., Register June 2020 No. 774, eff. 7-1-20; correction in (3) (b) 1., 2. made under s. 35.17, Stats., Register June 2020 No. 774; CR 21-070: am. (3) (a), cr. (3) (e) to (g), am. (4) (intro.), (b) (intro.), (c), cr. (4) (d), (5) (c) 3. Register July 2022 No. 799, eff. 8-1-22.

NR 812.15 NR 812.15 Flowing wells.

NR 812.15(1) (1) Control of flow. When a well driller or well constructor constructs a flowing well, the flow shall be confined to the interior of the well casing. When the flow of water is not contained to the interior of the well casing using planned construction methods, the well driller or well constructor shall notify the department of the location of the flowing well immediately, and take one of the following actions:

NR 812.15(1)(a) (a) Reconstruct the well to contain the flow to the interior of the casing.

NR 812.15(1)(b) (b) Fill and seal the well according to one of the methods specified in s. NR 812.26 (6) (i).

NR 812.15(2) (2) General requirements. A flowing well constructed with an upper enlarged drillhole shall be grouted in accordance with par. (c). When a new well is constructed to replace a well with uncontrolled flow, the well shall be constructed to meet all of the following requirements:

NR 812.15(2)(a) (a) Upper enlarged drillhole requirement. An upper enlarged drillhole shall be constructed in accordance with the requirements specified in subs. (3) or (4).

NR 812.15(2)(b) (b) Driving or advancing casing. Steel well casing shall be driven or advanced only through the bottom of an upper enlarged drillhole constructed in accordance with the requirements specified in subs. (3) or (4). The upper enlarged drillhole shall be kept filled with drilling mud with a mud weight of at least 9 pounds per gallon or with dry granular bentonite, which shall be maintained around the outside of the casing. Approved drilling additives may be added to the drilling mud to increase the mud weight.

NR 812.15(2)(c) (c) Grouting requirement. The annular space of a flowing well shall be grouted with neat cement using the methods specified in s. NR 812.20.

NR 812.15(3) (3) Construction requirements in unconsolidated formations. In addition to the general requirements of this section and the requirements specified in ss. NR 812.10 to NR 812.13, a well driller or well constructor shall construct or reconstruct a flowing well in unconsolidated formations according to all of the following requirements:

NR 812.15(3)(a) (a) Upper enlarged drillhole. An upper enlarged drillhole shall be constructed to at least 25 feet or halfway through any known confining bed, whichever is deeper, except when the well is double cased in accordance with par. (e).

NR 812.15(3)(b) (b) Minimum diameter. The upper enlarged drillhole shall be a minimum of 4 inches larger than the nominal diameter of any casing to be grouted, except as allowed under par. (e).

NR 812.15(3)(c) (c) Method of keeping the hole open. The upper enlarged drillhole shall be kept open during construction using any of the following methods:

NR 812.15(3)(c)1. 1. Driving temporary casing to the depth specified in par. (a).

NR 812.15(3)(c)2. 2. Circulating drilling mud with a weight of at least 9 pounds per gallon. Additives approved under s. NR 812.091 may be added to the drilling mud to increase the mud weight.

NR 812.15(3)(d) (d) Screens. A well screen may be placed according to the requirements specified in s. NR 812.13 (4) prior to grouting.

NR 812.15(3)(e) (e) Double cased wells. When a well is double cased, it shall be constructed in accordance with all of the following requirements:

NR 812.15(3)(e)1. 1. The nominal casing diameter of the outer casing may be reduced to a minimum of 2 inches in diameter greater than the nominal diameter of the inner casing when welded steel or flush-threaded thermoplastic casing is used for an inner casing.

NR 812.15(3)(e)2. 2. An upper enlarged drillhole shall be constructed into the confining bed in accordance with par. (c).

NR 812.15(3)(e)3. 3. The outer casing shall be placed in the upper enlarged drillhole and grouted in place according to the requirements specified in sub. (2). The grout shall be allowed to set for a minimum of 24 hours before drilling continues.

NR 812.15(3)(e)4. 4. A second upper enlarged drillhole shall be constructed to at least the minimum casing depth for the formation encountered and in accordance with par. (c).

NR 812.15(3)(e)5. 5. The inner casing shall be placed in the upper enlarged drillhole and grouted in place according to the requirements specified in sub. (2). The grout shall be allowed to set for a minimum of 24 hours before drilling continues.

NR 812.15(4) (4) Construction requirements in bedrock formations. In addition to the general requirements of this section and the requirements specified in ss. NR 812.10 to 812.14, a well driller or well constructor shall construct or reconstruct a flowing well in bedrock formations according to all of the following requirements:

NR 812.15(4)(a) (a) Upper enlarged drillhole.

NR 812.15(4)(a)1. 1. An upper enlarged drillhole shall be constructed to the minimum casing depth for the bedrock formation encountered or halfway through any known confining bed, whichever is deeper, except when the well is double cased in accordance with par. (e).

NR 812.15(4)(a)2. 2. When the depth to the top of bedrock is more than the minimum casing depth for the bedrock formation encountered, the upper enlarged drillhole depth may be reduced to 25 feet below ground surface when steel casing is driven or advanced according to the requirements of sub. (2) (b).

NR 812.15(4)(b) (b) Minimum diameter. The upper enlarged drillhole shall be a minimum of 4 inches larger than the nominal diameter of any casing to be grouted, except when the well is double cased in accordance with par. (e).

NR 812.15(4)(c) (c) Method of keeping the hole open. The upper enlarged drillhole shall be kept open during construction using any of the following methods:

NR 812.15(4)(c)1. 1. Driving temporary casing to the depth of casing setting or to the top of bedrock.

NR 812.15(4)(c)2. 2. Circulating drilling mud with a weight of at least 9 pounds per gallon. Approved additives may be added to the drilling mud to increase the mud weight.

NR 812.15(4)(d) (d) Seating casing. Any casing set into an upper enlarged drillhole constructed more than 5 feet into bedrock shall be driven to a firm seat prior to grouting the annular space.

NR 812.15(4)(e) (e) Double cased wells. When a well is double cased in bedrock, it shall be constructed in accordance with all of the following requirements:

NR 812.15(4)(e)1. 1. The outer casing may be reduced to a minimum of 2 inches in diameter greater than the nominal diameter of the inner casing when welded steel casing is used as an inner casing. The minimum diameter of an inner casing is 6 inches.

NR 812.15(4)(e)2. 2. An upper enlarged drillhole shall be constructed into the confining bed in accordance with par. (c).

NR 812.15(4)(e)3. 3. The outer casing shall be placed in the upper enlarged drillhole and grouted in place according to the requirements specified in sub. (2). The grout shall be allowed to set for a minimum of 24 hours before drilling continues.

NR 812.15(4)(e)4. 4. A second upper enlarged drillhole shall be constructed to at least the minimum casing depth for the formation encountered and in accordance with par. (c).

NR 812.15(4)(e)5. 5. The inner casing shall be placed in the upper enlarged drillhole and grouted in place according to the requirements specified in sub. (2). The grout shall be allowed to set for a minimum of 24 hours before drilling continues.

NR 812.15 History History: CR 18-095: r. and recr. Register June 2020 No. 774, eff. 7-1-20; correction in (4) (intro.) made under s. 35.17, Stats., Register June 2020 No. 774; CR 21-070: am. (2) (c) Register July 2022 No. 799, eff. 8-1-22.

NR 812.151 NR 812.151 Heat exchange drillhole location and construction requirements. A heat exchange driller is responsible for constructing all heat exchange drillholes in accordance with the requirements specified in ss. NR 812.10 to 812.12 and all of the following requirements:

NR 812.151(1) (1) License requirement. An individual who performs heat exchange drilling is required to be a licensed heat exchange driller except that a license is not required to perform heat exchange drilling if an individual is employed by a licensed heat exchange driller or a person registered as a business to perform heat exchange drilling and all other requirements under this section and ss. NR 812.10 to 812.12 are met.

NR 812.151(2) (2) Approvals. A heat exchange driller shall obtain any approvals required in compliance with s. NR 812.09 (4) (w), (x), (y), or (z) prior to starting drilling and shall follow any conditions required by an approval.

NR 812.151(3) (3) Notification of drilling. A heat exchange driller shall obtain a well notification permit from the department at least 24 hours prior to the start of drilling.

NR 812.151(4) (4) Location.

NR 812.151(4)(a) (a) A heat exchange driller shall ensure that heat exchange drillholes are separated from potential contamination sources. A distance of 10 feet shall be maintained between a heat exchange drillhole and any of the following:

NR 812.151(4)(a)1. 1. A non-municipal water supply well.

NR 812.151(4)(a)2. 2. An on-site waste disposal system.

NR 812.151(4)(a)3. 3. A buried fuel storage tank.

NR 812.151(4)(b) (b) Prior department approval is required for any heat exchange drillhole located within 400 feet of a municipal water supply well.

NR 812.151(5) (5) Temporary casing. A heat exchange driller may use any of the following materials for temporary casing for heat exchange drillholes:

NR 812.151(5)(a) (a) Steel casing meeting the requirements specified in s. NR 812.11 (6).

NR 812.151(5)(b) (b) Thermoplastic casing meeting the requirements specified in s. NR 812.11 (7), but only in caving sand formations.

NR 812.151(6) (6) Pressure testing. Vertical heat exchange loop piping shall be pressure tested with potable water or an approved fluid in the loop, according to manufacturer’s specifications.

NR 812.151(7) (7) Drilling fluids. Drilling fluid shall be less dense than the grout to facilitate proper sealing of heat exchange drillholes.

NR 812.151(8) (8) Surface protection. A heat exchange driller shall protect heat exchange drillholes to prevent surface contamination from entering the drillhole during the drilling operation and when the driller is not at the drilling site. Drillholes may not remain open and ungrouted for more than 24 hours after completion.

NR 812.151(9) (9) Grouting. All materials used to grout a heat exchange drillhole shall be approved for use under s. NR 812.091 and shall meet the requirements specified in s. NR 812.11. A heat exchange driller shall use one of the following materials to grout heat exchange drillholes:

NR 812.151(9)(a) (a) Neat cement, if potable water or an approved fluid is continuously circulated in the loop pipe to prevent potential loop pipe deformation.

NR 812.151(9)(b) (b) A cement-bentonite mix.

NR 812.151(9)(c) (c) Sodium bentonite.

NR 812.151(9)(d) (d) Sodium bentonite-sand grout.

NR 812.151(9)(e) (e) Carbon-bentonite grout.

NR 812.151(10) (10) Grouting method. A heat exchange driller shall use the following method to grout heat exchange drillholes:

NR 812.151(10)(a) (a) Grout shall be placed in one continuous operation, if possible.

NR 812.151(10)(b) (b) For drillholes 25 feet in depth or more, grout shall be pumped through a tremie pipe under pressure according to the following requirements:

NR 812.151(10)(b)1. 1. The pipe shall be placed to the bottom of the drillhole and the grout shall be placed from the bottom up.

NR 812.151(10)(b)2. 2. The tremie pipe shall be kept submerged in the grout at all times during grouting.

NR 812.151(10)(b)3. 3. The tremie pipe may be pulled back during grouting as long as the end of the tremie pipe remains submerged in the grout.

NR 812.151(10)(c) (c) For drillholes less than 25 feet in depth, grout may be placed using a gravity method as specified in s. NR 812.20 (4).

NR 812.151(11) (11) Fusion welding. Fusion welding connection for vertical heat exchange piping shall be done using socket fusion, saddle fusion or butt fusion type, in accordance with pipe manufacturer’s instructions or as referenced in ASTM D 2610, D 2683 and D 2657. Joint surfaces shall be clean and moisture free.

NR 812.151(12) (12) Reporting. A heat exchange driller shall submit a report of the heat exchange drillhole project, on a form prescribed by the department, within 30 days following the date of completion of the project.

NR 812.151(13) (13) Heat exchange fluids. Only department approved heat exchange fluids may be used in the piping placed in heat exchange drillholes.

NR 812.151(14) (14) Filling and sealing. Unused heat exchange loops and drillholes shall be filled and sealed using the materials and methods specified in s. NR 812.26.

NR 812.151 History History: CR 18-095: r. and recr. Register June 2020 No. 774, eff. 7-1-20.

NR 812.152 NR 812.152 Construction requirements for potable high capacity wells, potable school wells, and wastewater treatment plant wells. Potable high capacity wells, potable school wells, and wastewater treatment plant wells shall be planned and constructed according to the location, approval, and general requirements speecified in ss. NR 812.08 to NR 812.12, and according to all of the following requirements:

NR 812.152(1) (1) Minimum diameter. The minimum casing and lower drillhole diameter for potable high capacity wells, potable school wells and wastewater treatment plant shall meet the following requirements:

NR 812.152(1)(a) (a) Four inches for wells completed in unconsolidated formations.

NR 812.152(1)(b) (b) Six inches for wells completed in bedrock formations.

NR 812.152(2) (2) Casing material. Only steel well casing pipe meeting the requirements of s. NR 812.11 (6) may be used.

NR 812.152(3) (3) Upper enlarged drillhole. An upper enlarged drillhole is required for all wells. An upper enlarged drillhole shall be constructed according to the following requirements: