Chapter NR 812

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:

NR 812.152(3)(a) (a) An upper enlarged drillhole shall be a minimum of 3 inches larger than the outside diameter of welded casing pipe, or 3 inches larger than the diameter of the casing couplings, when couplings are used.

NR 812.152(3)(b) (b) The upper enlarged drillhole shall be constructed to at least the minimum casing depth requirements specified in sub. (4).

NR 812.152(3)(c) (c) The upper enlarged drillhole shall be maintained at full diameter for the entire depth by any of the following methods:

NR 812.152(3)(c)1. 1. Circulating bentonite drilling mud.

NR 812.152(3)(c)2. 2. Setting a temporary casing to the bottom of the drillhole, or to the top of bedrock.

NR 812.152(4) (4) Casing depth. Minimum casing depths are measured from the ground surface. All wells shall be constructed with casing that extends to the minimum depth for the geologic formation they are completed in according to the all of the following requirements:

NR 812.152(4)(a) (a) Wells completed in unconsolidated formations.

NR 812.152(4)(a)1. 1. Sixty feet or 20 feet below the static water level when the static water level is greater than 40 feet.

NR 812.152(4)(a)2. 2. One hundred feet, or 20 feet below the static water level when the static water level is greater than 80 feet, when the well is to supply water for a wastewater treatment plant and there is a treatment pond or lagoon or sludge beds on the property.

NR 812.152(4)(b) (b) Wells completed in bedrock.

NR 812.152(4)(b)1. 1. Sixty feet or to the depth of bedrock when the top of bedrock is more than 60 feet below ground surface.

NR 812.152(4)(b)2. 2. One hundred feet when the well is to supply water for a wastewater treatment plant and there is a treatment pond or lagoon or sludge beds on the property.

NR 812.152(5) (5) Grouting. The grouting of an annular space shall be accomplished according to all of the following requirements:

NR 812.152(5)(a) (a) Only neat cement grout meeting the specification under s. NR 812.11 (15) (b) shall be used.

NR 812.152(5)(b) (b) Grout shall be placed using an approved pressure grouting method as specified in s. NR 812.20 (3), except that the grout shall be allowed to set for a minimum of 24 hours before drilling is resumed.

NR 812.152(5)(c) (c) Any temporary casing used during the construction of the upper enlarged drillhole shall be removed.

NR 812.152(6) (6) Driving or advancing casing. Casing may be placed to the bottom of an upper enlarged drillhole meeting the requirements specified in sub. (3) and driven or advanced through unconsolidated material to the final casing depth or to the top of bedrock.

NR 812.152(7) (7) Screens. Screens shall meet all of the following requirements:

NR 812.152(7)(a) (a) Screens shall be continuous-slot screen, v-shaped or wire-wrap on a rod base type and composed of stainless steel or lead-free brass.

NR 812.152(7)(b) (b) Screens may be permanently attached to the casing or riser pipe, or the screen may be placed using the bail-down method or by pushing the screen to the bottom of the casing and pulling it back to expose the screen.

NR 812.152(8) (8) Gravel packs. Gravel packs shall be placed according to the requirements specified in s. NR 812.16.

NR 812.152(9) (9) Geologic samples. Geologic samples shall be collected and submitted according to the requirements specified in s. NR 812.12 (11) (b) from all of the following:

NR 812.152(9)(a) (a) All potable school wells.

NR 812.152(9)(b) (b) High capacity potable wells when required by an approval issued by the department.

NR 812.152 History History: CR 18-095: r. and recr. Register June 2020 No. 774, eff. 7-1-20.

NR 812.16 NR 812.16 Gravel packs.

NR 812.16(1) (1) Conditions. A well driller or a well constructor may construct a screened well with a gravel pack under any of the following conditions:

NR 812.16(1)(a) (a) In an unconsolidated formation well when the natural formation comprising the aquifer is very fine grained or when the aquifer formation is highly variable in size.

NR 812.16(1)(b) (b) In loosely cemented sandstone aquifers that require screening to prevent sand pumping conditions.

NR 812.16(1)(c) (c) In badly fractured or decomposed crystalline bedrock formations.

NR 812.16(2) (2) Material. The gravel or sand used to construct a gravel pack shall meet the requirements specified in s. NR 812.11 (12).

NR 812.16(3) (3) Screens. Screens to be placed in gravel pack wells shall have a set of centering guides on the top and bottom of the screen to ensure an even gravel pack. The screen slot openings shall be sized to retain 90% of the gravel pack. Screen types and materials shall meet the requirements specified in s. NR 812.11 (11). The screen may either be permanently welded or threaded onto the bottom of the well casing pipe or may be installed by pushing the screen to the bottom of the casing pipe and then pulling back the casing pipe to expose the screen.

NR 812.16(4) (4) Placement. Gravel packs shall be placed in accordance with all of the following requirements:

NR 812.16(4)(a) (a) The gravel pack shall be placed through a tremie pipe placed in the annular space.

NR 812.16(4)(b) (b) The gravel pack shall surround the entire screen and shall extend at least 2 feet above the top of the screen.

NR 812.16(4)(c) (c) At least a 2-foot sand seal shall be placed upon the top of the gravel pack to prevent the required annular space sealing material from entering the gravel pack.

NR 812.16(4)(d) (d) For potable wells, the gravel pack may not extend closer to the ground surface than the minimum depth for the upper enlarged drillhole specified in s. NR 812.152 (3).

NR 812.16(4)(e) (e) For nonpotable high capacity wells, the gravel pack may not extend more than 20 feet above the top of the screen.

NR 812.16(5) (5) Thickness. The diameter of the upper enlarged drillhole shall be sized to accommodate the thickness of the gravel pack. The gravel pack shall be at least 2 inches greater than the nominal radius of the screen.

NR 812.16 History History: CR 18-095: r. and recr. Register June 2020 No. 774, eff. 7-1-20.

NR 812.18 NR 812.18 Welding procedures. Plain end well casing pipe shall be welded watertight using welding procedures for plain end well casing pipe in accordance with the specifications in the American Welding Society manual AWS D10.12, “Guide for Welding Mild Steel Pipe.” Well casing pipe to be welded shall conform to the specifications in s. NR 812.11 (6). Pitless adapter connections to well casing pipe shall be made watertight in accordance with welding procedures in the American Welding Society manual AWS D1.1, “Structural Welding Code-Steel.”

NR 812.18 Note Note: Copies of AWS manuals may be obtained directly from the American Welding Society’s website at www.aws.org. Copies are also on file at the offices of the department and the legislative reference bureau.

NR 812.18 History History: CR 18-095: r. and recr., Register June 2020 No. 774, eff. 7-1-20.

NR 812.19 NR 812.19 Well plumbness and alignment. A well driller or well constructor shall construct a well to meet all of the following requirements:

NR 812.19(1) (1) Plumbness. The deviation per 100 feet of well depth from plumb of the center line of the well may not exceed 75% of the well diameter for any well with casing that is 10 inches in diameter or larger.