NGWA Augering And Monitoring Well Practice Exam

The final step is installing the surface seal and headworks. After drilling the borehole, placing the casing and screen, and backfilling the annulus around the screen with filter material (like sand) to support the screen and create a proper filter zone, you close the well at the surface. The surface seal is applied at the top to prevent surface water and contaminants from moving down the borehole and to stabilize the upper portion of the well. The headworks—such as the protective cap, vent, and access fittings—are then installed to create a safe, functional entry point for sampling and monitoring while keeping the seal and inner well components protected. Because these elements seal and protect the bore at the ground surface, they are placed after everything beneath the surface has been constructed and stabilized. The earlier steps provide the structural and filtration setup that makes the surface sealing and headworks possible and effective.