Solinst Discrete Interval Sampler - Passive No Purge Samplers

Solinst Discrete Interval Sampler for Groundwater

  • Provides High Quality Samples
  • Easy to Operate and Transport
  • No Purge Sampling
  • No Mixing of Water from Different Levels Minimal Disturbance to the Water
Product Options


The 425 Discrete Interval Sampler produces representative water samples from areas beneath layers of floating product (LNAPL). Discrete interval sampling is a form of no purge sampling and is also ideal for obtaining product samples directly (DNAPL). Additionally, the 425 Discreet Interval Sampler can be used to profile open bodies of water, screened wells, and open boreholes. Passive samples can also be collected from distinct levels or points of inflow. By causing only negligible disturbance, the mixing of water from different levels is reduced to minimal levels.

With the 425 Discrete Interval Sampler, purging and purged-water disposal can be easily avoided. By passive sampling from a specific depth directly, the water collected is highly representative of the groundwater surrounding the well at that level.

Discrete Interval Sampler

Made from stainless steel, the Solinst Model 425 is highly durable and extremely reliable. LDPE tubing is mounted conveniently on the Solinst reel, which also features a pressure attachment. A high-pressure hand pump can be inserted into the attachment and used to apply and release pressure on the sampler. Sample-release devices are included with each Discreet Interval Sampler.

Before being lowered into the well, the sampler is pressurised with the high-pressure hand pump, preventing water from entering before the sampling zone is reached. Once at the appropriate depth this pressure is released and hydrostatic pressure fills the sampler with water from the proper sampling zone. Water is unable to enter the tubing because of a floating checkball located inside the passive sampler, making tubing decontamination unnecessary.

Once filled, the passive sampler is pressurised again and returned to the surface. Then, the passive is decanted by the sample-release device, which regulates flow and minimises degassing.

When a product layer is located on the surface of the sampling source, the 425 Discreet Interval Sampler is able to obtain samples that are uncontaminated by the upper layer, making it perfect for groundwater sampling.

Manufactured by: Solinst
Model: Solinst Discrete Interval Sampler for Groundwater

Services offered for this product

  • Sales
  • Rental
  • Installation
  • Calibration
  • Maintenance


Obtaining a representative groundwater sample from below oil/product layers
Discrete interval sampling in lakes, rivers and wells
Chemical profiling of wells
Sampling at points of inflow to well
LNAPL and DNAPL sampling


Recommended Operating Pressure
Submerged Depth
25 208148
50 3015217
100 5030364
200 9560660
300 14090 952
500 2251501540
Operating Pressure = (Submerged Depth in feet x 0.43) + 10 psi
(Submerged Depth in meters x 9.8) + 70 psi
Discrete Interval Sampler Capacity
English Units Metric Units
Size Capacity Size Capacity
1" x 2' 6 oz25.4 mm x 610 mm190 ml
1.66" x 2' 18 oz42 mm x 610 mm475 ml
2" x 2' 27 oz50.8 mm x 610 mm800 ml
1" x 4' 12 oz25.4 mm x 1220 mm365 ml
1.66" x 4' 32 oz42 mm x 1220 mm 1000 ml
2" x 4' 61 oz50.8 mm x 1220 mm1800 ml
Other diameters and lengths available, on request.