THE purpose of groundwater sampling is to retrieve a water sample that exactly represents the in-situ chemical characteristics of water below the ground surface.
Sampling techniques range from simple to highly sophisticated depending on the extent of analysis performed in the laboratory, according to ECO Environmental Pty Ltd , who specialise in environmental monitoring and sampling equipment.
When to use a bailer
The bailer is useful as a sample collection device if the well is first purged using a less disturbing method (such as peristaltic pump or 12V pump), when the well is slow to recover or when there is very little stagnant water to be removed prior to sample collection.
What is a bailer?
Most bailers consist of some form of tubing with a one-way check valve at the bottom. Water in a tank or groundwater well will fill the bailer when it is lowered into it. On retrieving the bailer, the check valve closes containing a sample of the contents of the well or tank.
Bailers come in various types and are made from various materials to ensure sample quality:
* ECOBailer Pro Disposable PVC Bailers
The ECOBailer Pro offers the latest in bailer innovation at a very affordable price says ECO Environmental. Complete with a emptying cup that connects to an inline filter (uses small barb), the ECOBailer Pro is packed full of features that will make bailing faster and easier.
Why choose the ECOBailer Pro?
In addition to the emptying cup, the 'big mouth' design ensures that the ECOBailer Pro sinks as well as weighted bailers without requiring additional weighted material. The bailer also incorporates a new pour spout allowing samples to easily be poured from the top off the bailer.
* Clearview* PVC Disposable Bailers
Clearview Disposable PVC Bailers are truly the highest quality disposable bailers in the field, says ECO Environmental. They sink fast without weight, do not bend or distort and retrieve large volumes of groundwater.
In comparison, most polyethylene bailers leak. The leak can be a few drops per second or enough to empty a bailer before it is retrieved. The Clearview specially designed ball valve virtually eliminates all leakage allowing customers to save time and money by reducing sampling costs.
Why choose PVC Bailers?
- PVC sinks easily in water due to its specific gravity relative to water
- No weights to restrict flow of sample entering and exiting bailer
- PVC is very ridged, stays straight, never distorting under normal care
- The PVC material is transparent and assists in field sampling
- Clearview Teflon and Polyethylene Bailers available on request
- Various diameters available: 38mm, 19mm and 12mm
- Sold individually or in boxes of 24.
* Clearview Polyethylene Disposable Bailers
Made of virgin high density polyethylene tubing (tops and bottoms) with a high grade PVC ball that helps to deter clogging, these polyethylene bailers are perfect for field sampling.
The rugged design minimises sample loss between ball and bailer whilst the HDPE construction ensures optimum sample quality every time.
Why choose Polyethylene Bailers?
- Samples can be poured accurately, with little or no splashing
- Strong ridged tethering attachment for secure fastening of bailer rope
- Each part is press fitted and double welded, to assist in the secure bonding of tube to top device.
* Clearview Hydrocarbon Disposable PVC Bailers
The Clearview Hydrocarbon Bailer is designed for the collection of hydrocarbon liquids or LNAPL (light non-aqueous phase liquids).
The bailer is designed with a larger diameter inlet section that reduces surface tension. When lowered into the product layer and retrieved slowly the polyethylene ball valve allows water to escape but leaves a free product sample within the bailer.
These bailers are ideal for obtaining product-only samples and provide a visual identification of the product thickness within a borehole. This is a low cost manual method for collecting LNAPL and very simple to use.
* Clearview Teflon Disposable Bailers
Clearview Disposable Teflon Bailers provide a simple sampling option for more sensitive trace organic sampling. They are made of virgin Teflon and have no weights to restrict the flow of samples entering and exiting the bailer.
Why choose Polyethylene bailers?
- Teflon is extremely inert offering the best sample quality of any bailer.