Groundwater Sampling

There are two primary groundwater sampling methods using Direct Push Technology (DPT):

 

Isolated grab sampling Open hole piezometer     sampling

 
Isolated Grab Sampling A common practice when the aquifer offers sufficient recharging to provide the desired volumes in a short amount of time, and when soil sampling above the groundwater is not required.

Open Hole Piezometer Sampling Becomes practical when the aquifer's recharging qualities cause delays in acquiring sufficient groundwater from a boring, or when continuous core soil sampling precedes the groundwater sample. Isolated Grab Sampling and Open Hole Piezometer Sampling are accomplished using the following tools and supplies:

 

Screen Point 15 Sampler One-half inch Schedule 40 PVC

 

 

Screen Point 15 Sampler

The Screen Point 15 Sampler is a very common tool for groundwater grab samples. The sampler is comprised of a hollow cylindrical sheath of hardened steel that measures four feet in length with an outside diameter (OD) of 1.5 inches. An expendable drive point and a drive head are placed on either end of the sampler, which is then driven to the desired depth. The Screen Point 15 uses either a stainless steel screen or a Schedule 80 PVC screen that is sealed inside the sheath with Neoprene O-rings to prevent infiltration of formation fluids until the desired depth is attained.

Groundwater Sampler Standard Operating Procedure

 

Open Hole Piezometer

The Open Hole Piezometer is typically used to collect groundwater when a continuous core soils sample has been collected and the boring remains open. Other practical applications for this method include slow charging aquifers. In lieu of leaving a Screen Point 15 Sampler in the ground with a tool chain while waiting for the sampler, PVC can be used as a temporary piezometer to save time and money. The PVC most commonly used is one-half inch Schedule 40. Screened and blank sections are typically five feet in length.

Open Hole Piezometer Standard Operating Procedure