Monitoring Wells

ZEBRA has responded to our clients' requests to install a wide variety of small diameter materials using our fleet of Direct Push units. The intended use of these installations has been client and site specific with applications including sparge points, vapor monitoring points, monitoring/recovery wells, bio-nutrient injection points, and observation points to measure the radius of influence of SVE and injection systems.

ZEBRA is currently using 3.25" and 2.125" probe rods to install sparge/monitoring points. The inside diameter of these rods allows the installation of 2" and 1" ID Schedule 40 PVC screen as well as pre-packed filter screens.

In addition to installing PVC, ZEBRA has installed a wide range of materials including stainless, galvanized and black steel, Teflon, HDPE, woven poly propylene and woven stainless steel mesh screens. The consultants' requirements and the site conditions will dictate the design specifications. Virtually any configuration of screen (i.e. length, diameter, material of construction) can be custom manufactured, given enough lead time.

Small diameter monitoring points

Typically, this option involves the installation of a small diameter (1/2" to 1 1/4") monitoring point constructed of flush threaded PVC pre-packed or slotted PVC screen with galvanized and stainless steel screens and Schedule 40 PVC riser.

The installation of small diameter monitoring points can be accomplished by several methods. For shallow installations, a blind probe is driven to the desired depth and withdrawn. The PVC or steel monitoring point is then placed/driven down the open probe hole. If the depth of placement and/or subsurface conditions prevent this method of installation, a soil core can be removed using the MC Sampler. Another option offered by ZEBRA to install 1/2" to 2" PVC monitoring points is to drive specially designed probe rods with a larger interior diameter. (2 1/8" or 3.25")

In order to install PVC screen using the rod/casing, an expendable drive point is fitted into the leading rod and the rod/casing is then driven to the desired depth. It should be noted that the larger outside diameter of the rod/casing (2 1/8" or 3.25") will reduce the terminal depth of placement. Once the rod/casing is at the appropriate depth, flush threaded Schedule 40 PVC riser and the monitoring point screen is inserted down the interior cavity and the rod/casing is the retrieved leaving the expendable point and PVC screen and riser in place.