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The only way to precisely know what is in your water is to have it tested. Generally the only required test for individual supplies is that for bacteria contamination, conducted by the local health department. Upon special request and indicated need the local health department or the Florida Department of Environmental Regulation can run additional tests. If a homeowner is simply curious or has personal concern, private testing sources will have to be used. This testing may become quite expensive.

The first step for any test is getting a reliable, representative sample. The need for careful sampling techniques varies according to the constituent being tested, i.e. bacteria and volatile organics are very sensitive to sample collection procedure while hardness and salts are fairly insensitive to sampling technique. Storage procedures before analysis and time between sampling and analysis are also very important but again vary substantially for each substance.

A general procedure for taking a sample is given below and would be sufficient for many problems including bacteria. In any cases where there is doubt, the laboratory performing the test should be contacted for instructions and a sampling bottle. In fact, in some cases the laboratory may want to take the sample. The following procedures should be followed for general sampling:

The sampling bottle should be clean and sterile with nothing except the water to be sampled coming in contact with the inside or cap of the bottle.

A faucet without leaks around the handle should be selected for sampling. It must be cleaned and dried.

The water should run for an ample period of time to ensure fresh water from the well before collecting a sample. The water should not make contact with any object before running into the bottle. The sample should be capped immediately to preserve volatile compounds in the water and prevent atmospheric contamination.

The sample should be analyzed within 24 hours to give accurate results. For best results, on-site testing of water is suggested if possible.

In making a decision whether to test for organic compounds, the following should be considered. First, are there any industrial disposal sites, pesticide users, machine shops, automotive garages, or other industries close enough to contaminate the aquifer? Second, is there any source of chlorine near the aquifer? Chlorinated water can have elevated organic halide levels, commonly trihalomethanes (MCL = 0.1 mg/l). Research is currently being conducted to modify the treatment process to keep these substances from drinking water. However, for now, chlorination will continue to be used to kill infectious organisms in water.