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Monitor Well Plugs

Monitor wells are becoming more popular as awareness of water contamination possibilities become increasingly more of a concern for drinking water. Monitor wells allow water samples to be taken from groundwater representing the physical and chemical properties of the aquifer being investigated. Monitor wells can be strategically located near manufacturing plants, underground gasoline tanks, and many other places of concern for water quality protection. Monitor wells help provide detection of harmful substances in ground water so appropriate action can be taken to prevent and/or treat them. PlumbingSupply.com® is your source for top quality locking monitor well plugs.

Monitor Well Locking Plugs

locking monitor well plug
  • Ideal for safely sealing and locking monitor wells
  • Complies with all EPA requirements for locking plugs
  • Designed to seal Schedule 40 piping
  • 2" and 4" sizes can also be used to seal Schedule 5 pipe
  • Top and bottom plates made with chemical and petroleum resistant Estalock® plastic
  • Petroleum resistant nitrile butadiene rubber (NBR) sealing ring
  • Stainless steel carriage bolt and nut
  • Chromate coated locking latch
  • Each locking plug includes one solid brass padlock
example of locking plug for monitor wells installed

As the stainless steel carriage bolt is tightened, the nitrile butadiene rubber sealing ring is squeezed between the top and bottom plate. This action forces the sealing ring tightly against the inside of the pipe creating an air and water tight seal. To remove the plug you will need to un-tighten the stainless steel carriage bolt which will relieve the pressure on the sealing ring so you can pull it out of the pipe.

Monitor-Well Locking NBR Plugs - with Padlock

Part # Nominal Size
(inside pipe)
Range of Use
(approx.)
Maximum Back Pressure Price & Quantity
271648 1" - 1 1/4" 1" - 1 3/8" 6.5 psi (15 ft.) $21.30
271675 2" 1 7/8" - 2 5/16" $23.62
271669 3" 2 13/16" - 3 1/8" $25.11
271683 4" 3 13/16" - 4 3/8" $27.88
271691 6" 5 3/4" - 6 1/16" $55.42
Replacement Accessories
112941 Replacement Padlock - solid brass - for above locking plugs $7.44

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Frequently Asked Questions

Q. "I have worked with Schedule 40 pipe but what is Schedule 5 pipe?"
A. Schedule 5 pipe has a thinner pipe wall thickness than schedule 40 pipe. For example: a schedule 40 2" nominal pipe has a wall thickness of .154 inches (approx. 1/8"); a schedule 5 " nominal pipe has a much thinner wall thickness of .065 inches (approx. 1/16"). Schedule 5 pipe is not very common and each pipe size has a different wall thickness. You will need to consult with the pipe manufacturer for each specific size of pipe to find out the wall thickness.

Q. "Does the Locking Plus fit all of the way inside the pipe?"
A. The bottom plate portion of the plug and the sealing ring fit all of the way inside the pipe. But the top plate sits on top of the pipe to prevent the plug from slipping all the way down into the pipe well.

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