Section 812.23. Driven point (sand point) wells.

  Driven point wells are typically constructed in sandy soil areas with a high water table. Groundwater in these areas is very susceptible to contamination. Driven point wells shall be constructed to meet the following requirements:

(1)  The well shall be located on the highest point on the premises consistent with the general layout and surroundings, if reasonably possible, as specified in s. NR 812.08 (1) (b) and as far removed as possible from all potential contamination sources, but at least as far as the minimum separating distances required in s. NR 812.08 .

(2)  Well casing pipe used for driven point wells shall meet the requirements of s. NR 812.17 .

(3)  The well drive pipe shall extend 12 inches above the established ground surface, pump house or building floor, or above any concrete or asphalt platform surrounding the well at or above the established ground surface. In a floodfringe, the top of the well drive pipe shall terminate at least 2 feet above the regional flood elevation. Driven point wells may not be constructed in a floodway.

(4)  The diameter of the driven point well shall be selected and the expected depth considered so that the pump installation will meet the requirements of this chapter. For static water levels deeper than the lift of a shallow well pump, approximately 20 feet, a well drive pipe diameter sufficient to accommodate the packer-jet assembly in the well shall be selected to allow pumping with a deep well pump. When the requirements of sub. (5) are met and when the use of a shallow well pump is possible the minimum diameter of the driven point well is 1- ¼ inches.

(5)  The well drive pipe, not including the screen, of a driven point well shall extend to a depth of 25 feet or to a depth 10 feet below the static water level in the well, whichever is greater.

(6)  Driven point wells, when protected against freezing, may be installed with a protective outer sleeve below frost depth as shown in figure 18a. When installed in this manner, the top of the annular space between the well and the protective sleeve shall be sealed watertight with a sanitary well seal.

(7)  Pump installations for driven point wells shall be completed according to s. NR 812.32 .

(8)  When a well drive pipe is removed to replace a well screen, the replacement is new well construction and shall meet all the requirements of this chapter.

(9)  Screen selection for driven point wells is optional, except that screens having any lead content may not be used.

(10)  Starter drillholes not exceeding 10 feet deep may be constructed to facilitate driving the pipe. If a starter drillhole is constructed the annular space shall be sealed according to the percussion drilling methods specified in s. NR 812.13 (2) following completion. An attempt shall be made to remove any temporary outer casing. If possible, the temporary outer casing shall be removed.

History: Cr. Register, January, 1991, No. 421 , eff. 2-1-91; am. (4) and (6), Register, September, 1994, No. 465 , eff. 10-1-94.