Wisconsin Administrative Code
Department of Natural Resources
NR 800 - Environmental Protection - Water Supply
Chapter NR 812 - Well Construction And Pump Installation
Subchapter II - New Water Well and Heat Exchange Drillhole Construction and Reconstruction and Filling and Sealing of Wells and Drillholes
Section NR 812.22 - Well rehabilitation and batch chlorination

1. Noncontinuous chemical treatment of a well, except for batch chlorination, shall be conducted under the supervision of a licensed water well driller or a Wisconsin registered professional engineer. Acidation of a well shall be done with materials approved for use under s. NR 812.091 and in a manner to prevent damage to the well or pump and to prevent any hazard to humans or property. The acid shall be inhibited and shall be neutralized upon removal from the well.

2. Noncontinuous chemical treatment of pumps or pump intake screens shall be conducted under the supervision of a licensed pump installer or a Wisconsin registered professional engineer. Acidation of a pump or pump intake screen shall be done in a manner described under subd. 1.

1. `Blasting.' When using explosives to increase or recover the yield of a well, the explosive charge shall be set at least 10 feet below the bottom of the well casing pipe, which shall be filled with water or sand. A licensed water well driller shall supervise blasting work, which shall be performed by a blaster certified by the department of safety and professional services according to the requirements specified in ch. SPS 307. The well driller shall submit a report of results of the blasting within 30 days following the work on a well construction report form.

2. `Hydrofracturing or hydroflushing.' Hydrofracturing or hydroflushing of an aquifer by injecting potable chlorinated water into a crystalline bedrock formation well under high pressure is allowed. 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. Hydrofracturing or hydroflushing may only be performed under the supervision of a licensed water well driller. The upper packer may not extend up into the bottom of the well casing pipe nor higher than 40 feet below the ground surface. Hydrofracturing or hydroflushing in limestone or dolomite formations may be undertaken only after prior department notification. The well driller shall submit a report of the results of the hydrofracturing or hydroflushing no later than 30 days after completion of the work on a form specified by the department.

3. `Mechanical brushing.' A well may be mechanically brushed to loosen material attached to the inside of a casing, screen, or open drillhole.