Section 812.12. General drilled type well and heat exchange drillhole construction requirements.

 

(1)  Every well and heat exchange drillhole shall be planned and constructed so that:

(a) It is adapted to the geologic and groundwater conditions of the proposed well or heat exchange drillhole site to ensure full utilization of every natural protection against contamination of the water bearing formation or formations and to exclude possible sources of contamination.

(b) Wells will produce bacteriologically safe water.

(c) Wells will provide an adequate and contaminant free water supply, where the natural geologic and groundwater conditions allow.

(d) It will conserve groundwater.

(e) It will allow reconstruction, when necessary.

(2)  The construction of drilled wells shall comply with:

(a) The general and specific requirements outlined in ss. NR 812.13 to 812.16 ;

(b) The well casing pipe requirements of s. NR 812.17 ; and

(c) The requirements of Table I or II for low capacity potable wells, except school or wastewater treatment plant wells, but including noncommunity wells and nonpotable wells, or

(d) The requirements of Tables III and IV for potable high capacity, wastewater treatment plant and school wells.

(e) The well casing pipe depth requirements of ss. NR 812.13 to 812.16 and of Tables I to IV are such that the installed well casing pipe depth is referenced and measured from the ground surface, not from the top of the well casing pipe, at the time of completion of the well. A well is completed when all operations that require the use of drilling, driving or annular space sealing equipment have been completed.

(3)  A greater depth of well casing pipe shall be provided in special well casing pipe depth areas designated by the department where well histories show contamination extends to a greater depth. In some of these areas department approval shall be obtained for each well prior to construction.

(4)  Steel well casing pipe shall meet the requirements of s. NR 812.17 . Steel well casing pipe assembled with welded joints shall have beveled ends and all joints shall be welded according to the welding requirements outlined in s. NR 812.18 .

(5)  A drive-shoe shall be welded or threaded to the bottom of any string of well casing pipe to be driven including driving to a firm seat in bedrock when well casing pipe is set in an upper enlarged drillhole, except when the upper enlarged drillhole extends 20 feet or more into bedrock and the annular space is cement grouted before the lower drillhole is constructed, the use of a drive-shoe is optional. A drive-shoe is not required for any temporary outer casing. Thermoplastic well casing pipe may not be driven.

(6)  The well driller or well constructor shall complete the well construction such that the well casing pipe extends at least 12 inches above the final ground grade, above a pumphouse or building floor or above any concrete or asphalt platform installed at or above the established ground surface. In addition, for wells in floodplains, the top of the well casing pipe shall terminate at least 2 feet above the regional flood elevation. A well may not be constructed in a floodway on property that is either undeveloped or on property that has buildings but no existing potable well.

(7)  Well plumbness and alignment shall conform to the requirements of s. NR 812.19 .

(8)  Liners shall meet the requirements of s. NR 812.21 .

(9)  Grouting and sealing requirements shall conform to s. NR 812.20 .

(10)  The construction of flowing wells shall also comply with the construction requirements of s. NR 812.15 .

(10m)  Drilling fluid must be less dense than the grout to facilitate proper sealing of heat exchange drillholes.

(11)  Water used in the construction, reconstruction or redevelopment of wells shall be clear water obtained from an uncontaminated source. The water shall be disinfected with chlorine with a residual of 100 mg/l (parts per million) to reduce the effort involved in the final disinfection of the well and to reduce the possibility of groundwater contamination. The chlorine concentration may be mixed according to Table B in s. NR 812.22 (4) (d) . The drilling fluid shall be maintained with a free-chlorine residual of 10 mg/l (parts per million) during drilling.

(12)  Well construction shall be interrupted for at least 12 hours following placement of cement grout in the annular space between the well casing pipe and the upper enlarged drillhole or between a liner pipe and a lower drillhole and the well casing pipe.

(13)  Nonpotable wells shall be constructed according to the requirements for low capacity potable wells, except that well casing pipe 12 inches in diameter and larger used for nonpotable wells may have a lesser wall thickness than is required by Table V for the diameter of the well casing pipe used provided the pipe has a minimum wall thickness of 0.250 inches and is adequate in strength to make the well structurally sound. The drilling mud requirements during well drilling and the sodium bentonite annular space sealing requirements do not apply to nonpotable high capacity wells constructed with reverse rotary methods.

(14)  Starter drillholes 10 feet deep or less are not upper enlarged drillholes. Starter drillholes need not meet the minimum requirements for upper enlarged drillholes.

(15)  More stringent well construction methods including but not limited to deeper well casing pipe depth settings are required by th e department for wells constructed through formations where contaminant levels exceed the drinking water standards in s. NR 812.0 6 , and may be required when there is groundwater contamination exceeding ch. NR 140 enforcement standards on a property that is listed on the department ' s geographic information system registry of closed remediation sites. When drilling in areas where there are contaminated formations, and on properties where the water well or heat exchange driller or well constructor has been notified that the property is listed on the department ' s geographic information system registry of closed remediation sites, consultation with the department is required. If required by the department, special well and drillhole construction methods shall be utilized when constructing or reconstructing wells or drillholes located on properties that are listed on the department ' s geographic information system registry of closed remediation sites.

(16)  When a quarry is within 500 feet of any proposed water well, the upper enlarged drillhole and well casing pipe depth requirements shall be referenced from the bottom of the quarry and an additional 20 feet of upper enlarged drillhole, well casing pipe and cement grout shall be installed over the amount required in Table II and Table III. When the bottom of the quarry is or will be at an elevation higher than the elevation of the ground surface at the well site, this requirement does not apply. This requirement does not apply if the quarry is no longer used and is permanently filled with water.

(17)  When a sinkhole or an outcrop is within 250 feet of any proposed well, additional depth of the upper enlarged drillhole and well casing pipe may be necessary. Consultation by the well driller or well owner with the department is recommended.

(18)  Drill cutting samples from high capacity, school and wastewater treatment plant wells shall be collected at 5-foot depth intervals and at each change in geological formation. The samples shall be submitted to the Wisconsin geological and natural history survey for preparation of a certified log of the well.

(19)  When percussion drilling methods are used to construct a well as specified in s. NR 812.13 (2) or 812.14 (2) , rotary air methods may be used to construct an upper enlarged drillhole in noncaving formations to a depth not to exceed 20 feet, or may be used to construct a drillhole to facilitate the driving of temporary outer casing providing the drillhole is the same or smaller diameter as the outside diameter of the temporary outer casing and does not extend deeper than the 40-foot depth.

(20)  When percussion drilling methods are to be used to construct a well as specified in s. NR 812.13 (2) or 812.14 (2) , rotary-mud circulation techniques may be used to construct an upper enlarged drillhole below which the well casing pipe may be driven providing:

(a) The drillhole is at least 2 inches larger in diameter than the nominal well casing pipe diameter,

(b) The well casing pipe is assembled with welded joints, and

(c) The drillhole is kept full of drilling mud and cuttings while the well casing pipe is driven.

(21)  When using percussion methods for the construction of nonpotable high capacity wells and for low capacity wells except school and wastewater treatment plant wells, the minimum diameter of the upper enlarged drillhole may be reduced from 4 inches larger in diameter than the nominal diameter of the well casing pipe to 2 inches larger in diameter than the nominal diameter of the well casing pipe when:

(a) Steel well casing pipe assembled with welded joints is used, and

(b) The annular space sealing material is placed by using an approved pressure method.

History: Cr. Register, January, 1991, No. 421 , eff. 2-1-91; am. (1) (c), (3), (13), (15), (16), Tables I and II, cr. (1) (e), Register, September, 1994, No. 465 , eff. 10-1-94; CR 00-111 : am. (15), Register October 2001 No. 550 , eff. 11-1-01; CR 13-096 : am. (title), (1), cr. (10m), am. (15), CR 13-099 : cr. (2) (e), am. (16) Register September 2014 No. 705 , eff. 10-1-14; correction in numbering in (10m) made under s. 13.92 (4) (b) 1. , Stats., correction in (15) made under s. 35.17 , Stats., Register September 2014 No. 705 .

Note

In some areas of Wisconsin the useable aquifer is contaminated throughout its entire vertical extent. In such areas, it may not be possible to obtain bacteriologically safe water. Microsoft Windows NT 6.1.7601 Service Pack 1 The requirements of Tables I-IV are based on the geologic formation encountered at or near the ground surface, the geologic formation in which the well terminates, the type of drilling method used, the depth to which the upper enlarged drillhole extends into bedrock, for bedrock wells, and the static water level for unconsolidated formation wells. For specific requirements relating to percussion method drilling and rotary method drilling, see ss. NR 812.13 and 812.14 , respectively. Microsoft Windows NT 6.1.7601 Service Pack 1 A list of special well casing pipe depth areas and the required depths may be obtained from the department upon request. Greater depth of well casing pipe is recommended for wells constructed on high density tiered lots where possible contamination sources exist on neighboring up-slope lots. Additional requirements for more stringent well construction methods are found in sub. (15), regarding sites listed on the GIS Registry (formerly known as the GIS Registry of Closed Remediation Sites). Microsoft Windows NT 6.1.7601 Service Pack 1 The GIS Registry of Closed Remediation Sites has been renamed the GIS Registry. It is now a layer on the map view, RR Sites Map. Information about a specific site can be found int he tracking system, BRRTS on the Web. Both these applications can be found at http://dnr.wi.gov/topic/Brownfields/clean.html . Information on a specific site can also be obtained by calling the nearest regional DNR office. Microsoft Windows NT 6.1.7601 Service Pack 1