19. When the sealing of a groundwater withdrawal facility is required under this Regulation, it must be performed in accordance with the following conditions:
(1) the well must be drilled in such a way that, over a minimum depth of 5 m, it has a diameter at least 10 cm greater than the nominal diameter of the pipe casing;
(2) the permanent pipe casing, excluding the perforated casing, must descend to a minimum depth of 5 m;
(3) the annular space around the pipe casing must be filled, in accordance with good practice, to a minimum depth of 5 m using a material that ensures a watertight, durable seal, such as a cement bentonite mix or pure bentonite;
(4) the excess pipe casing must be removed without damaging the seal;
(5) the sealing must be performed under the supervision of a professional.
All work carried out after the sealing must be performed in a way that minimizes the effect on the seal.