Approved Drilling Fluid Additives and Bentonite Grouts - EH: Minnesota Department of Health

Approved Drilling Fluid Additives and Bentonite Grouts
Well Management Program

Following is a partial list of requirements for drilling fluids and grouts used in wells and borings in Minnesota (complete requirements can be found in Minnesota Rules, chapter 4725, Wells and Borings):

  • Drilling fluid additives, including bentonite, must meet the requirements of ANSI/NSF Standard 60-2003e.

  • Bentonite used for grout must meet ANSI/NSF Standard 60, or be a natural bentonite without additives.

  • Grout must be mixed into a water slurry and pumped through a tremie pipe or the casing.

  • Bentonite pellets, chips, and dry granular bentonite may be used only as an intermediate seal between a gravel pack and grout in any regulated well or boring. The layer of bentonite pellets, bentonite chips, or granular bentonite must not exceed 5 feet in thickness, must not extend into a confining layer, and must not extend more than 10 feet above the static water level.

The Minnesota Department of Health (MDH) has put together the following list of approved products:

The MDH list of ANSI/NSF Standard 60 Certified
Well Drilling Aids and Well Sealants (PDF)

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Contact the MDH Well Management Section
651-201-4600 or 800-383-9808

Minnesota Department of Health
Updated Wednesday, October 31, 2018 at 02:04PM