ZIST™In-Line Features:
• Isolate Well Screen During Purging and Sampling.
• Eliminate Draw-down During Monitoring.
• Limit Groundwater Removal to the Well Screen Zone Only.
• Significantly Reduce Purging and Sampling Time –and Cost –throughout the Life of the Project.
• No Bailing.
• Simultaneously Purge Nested and Clustered Well Systems.
• Simultaneously Obtain Water Level Data from All Zones within A Nest or Cluster.
• Compatible with Other Devices: ZIST™ Pumps Can Be integrated with Sensors, and Removed at Any Time.
• Easy to Maintain: O-Ring around ZIST™Tubular Docking Weight Can Be Replaced at Any Time.
• Easily Adapted for Rapidly Decreasing Water Levels.
• ZIST™Can Be Easily Integrated into 3/4-Inch, 1-Inch, 2-inch, 4-Inch and Any Other Well Diameters
ZIST eliminates draw-down, and reduces purge volume as a result of sampling mechanism. When 3-5 wet casing volumes are required, purge volume is reduced by as much as 60% by ZIST displacement systems.
ZIST™ provides verifiable isolation of the well screen when the pump is docked in the Well Screen Receptacle (located between the well screen and riser pipe).
The pump docks with the receptacle and does not sample water from the riser pipe above the receptacle. Draw-down does not need to be monitored.
The ZIST™RetroWell can be also used to isolate Passive Diffusion Bags (PDBs), Pressurised Bailers, water-sleeves, and sampling vials in existing 2”, 4”and all other wells. Samples are taken from only the well screen target zone.
In the case of PDBs, diffusion cross-over from riser pipe water is blocked and prevented from potentially biasing the PDB sample. Therefore, diffusion cross-over from riser pipe water is eliminated to prevent potential bias of the PDB sample.