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Environmental Monitoring & Sampling

Direct-Push has re-defined how contaminated sites are assessed

We are experts at executing environmental sampling programs at complex sites. CDS has a broad base of experience, at hundreds of sites across western Canada, using direct-push tools, techniques and equipment.

Direct Push continuous sampling

Over the years, we’ve worked with different sampling tools and techniques. We believe that direct-push is the best at balancing cost and quality - so do organizations and regulators across North America. We have advanced thousands of bore holes and completed monitoring wells across all western provinces under a variety of conditions. Direct-Push refers to tools and sensors that are “pushed” into the ground, usually by hydraulic percussion. Direct-Push assessment techniques are unique because they do not involve drilling to remove soil or make a path for the tool – like traditional augering methods.

Direct-Push has re-defined how contaminated sites are assessed – in many jurisdictions it is one of the few assessment techniques approved for use by regulators.

Benefits of the Direct-Push Method

There are numerous reasons why this technique has found such wide acceptance in the field, including:

  • No cuttings are produced during the sampling process
  • Probing is fast: typical penetration rates are from 5 to 12 feet (2 to 4 m) per minute (in certain soils)
  • The sampling process is fast; up to 20 to 30 sample locations per day
  • Produces relatively undisturbed soil cores, for easy viewing
  • Minimizes soil “smearing” across different zones
  • Minimal intrusion into aquifers
  • Prevents the volatization of contaminants
  • Assists in identifying small or discontinous granular soil lenses, which may facilitate the movement of contaminants
  • Can be used to sample subsurface media including soil, groundwater, and soil gas

Dual tube tooling is used to collect soil samplers continuously from the surface or from a desired depth below the surface while minimizing the chance of liner failure.

Figure 1

Push the dual tube sampling tools to the depth where soil sampling is to begin.

Figure 2

Once at depth, the internal extension attached to the inner drive tip is removed.

Figure 3

Add a liner, liner grabber, internal extension, threadprotector cap, and external drive head.

Figure 4

At this point the extensions are direct pushed approximately to the same length as the liner that is being used.

Figure 5

Upon collection of the sample, the internal extension with the attached liner and soil sample is removed.

Continuous sampling can be conducted by repeating steps shown in figures 3 and 5 to the maximum desired depth.