A. Introduction
There are few specified protocols for sampling springs; however, the ultimate goal remains unchanged from sampling other sources, which is to document natural water quality. Implemented sampling procedures should always consider this objective and include: 1. Implementing proper purging procedures, when necessary, 2. Sampling as close to the source as possible, 3. Documenting field water quality parameters, such as pH, temperature, dissolved oxygen, conductivity, etc., 3. Bypassing any treatment and 4. Utilizing sampling equipment that will not compromise sample integrity.
Client requests often include sampling springs that are and are not used as potable water sources. As a result, sampling conditions can be variable, ranging from sampling at the spring head emerging from a hillside (picture to the right) to collecting a sample from within a collection basin.
B. Sampling Methods/Collection
Springs flowing naturally do not require "purging" as needed for water wells. However, collecting an undisturbed sample can be a tedious task, if proper equipment is not used. Springs flowing from a hillside seep, as illustrated in the previous section, can be effectively sampled by inserting clean teflon tubing into the seep and allowing it to gravity feed down-slope. After a sufficient distance, sample bottles can be filled directly from the tubing. Care should always be taken to allow for the flushing of suspended sediment, disturbed while inserting the tubing. Field water quality parameters should also be collected and the spring's location documented.
2. Contained/Semi-Contained Springs Springs used as a potable water source are often housed in a pit or collection basin, as illustrated to the right. Often times, a sampling device (known as a bailer) can be used to sample at the spring seep location within the basin. In other cases, where the spring's precise entry point cannot be identified, it may be necessary to calculate the dimensions of the pit and drain sufficient water to induce fresh spring flow, prior to sampling. Frequent collection of field water quality parameters can also be of assistance in determining when sufficient water has been flushed.
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