Requirements for Joining Well Screen to PVC Well Casing - EH: Minnesota Department of Health --- -

Requirements for Joining Well Screen to PVC Well Casing
Well Management Program

Effective May 12, 2011, the Minnesota Department of Health Well Management Section adopted a policy allowing some alternatives to the connections currently required in rule.

Minnesota Rules, chapter 4725 currently requires that if a screen is attached or connected to plastic casing, the connection must be made by:

  1. a nontoxic packer (for example, a neoprene rubber “figure K” packer);
  2. a plastic coupling meeting the dimension requirements of ASTM Standard F480-02 (these couplings are not commonly available);
  3. flush-threaded joints meeting ASTM F480-02 (monitoring wells and environmental bore holes only); or
  4. a slip x-thread fitting meeting ASTM D2466-02 (for 4-inch and 5-inch diameter wells, only).

The rules do not require a connection between a screen and casing. For example, a telescoped screen can be installed inside a casing with no packer or other physical connection between the casing and screen.

For all practical purposes, the rules would allow only a telescoped screen (with or without a packer) for plastic well casing 6-inches or larger in diameter because there are no commonly available couplings that meet the requirements for joining a pipe size screen to plastic casing 6-inches or larger in diameter.

In order to provide well contractors with workable options for construction of plastic cased wells 6-inches in diameter and larger, with pipe size screens, the MDH has adopted the following policy:

  • The requirements of Minnesota Rules, part 4725.2550, subparts 1 and 2 for compliance with a particular ASTM standard or dimensions are waived for the screen connection to 6-inch and larger diameter plastic casings.
  • Plastic parts and related joining materials including solvent cements must comply with Minnesota Rules, part 4725.2550, subpart 3, which requires NSF compliance.
  • If a screen is attached or connected to the casing, the connection must be made by a threaded, solvent-welded, or welded joint or by a nontoxic packer (without requiring that the coupling or fitting meet any particular standard or dimensions). For PVC well casing, only a solvent-welded plastic coupling or fitting or nontoxic packer would be acceptable. The plastic coupling or fitting may connect to the screen with threads or a solvent weld.
  • Screws must not be used to join PVC casing (including joining casing to screen).

Please note that this policy does not modify the requirement that flush-threaded PVC casing may be used only in the construction of a monitoring well or environmental bore hole, and flush threaded PVC casing must meet the requirements of Minnesota Rules, part 4725.6650.

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Updated Thursday, March 05, 2015 at 04:24PM