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    Sample Requirements

    Sample containers
    Containers must be clean and free of any residue from former contents. One-gallon plastic drinking water jugs make good containers for water chemistry testing. After the container is empty, rinse it two to three times with the water that will be tested. Containers with residues of milk, juice, bleach, etc. may alter test results.  Plastic containers are preferred, and should have a secure, tight fitting lid.

    Samples for chemistry testing are accepted Monday-Friday from 8 a.m. to 2 p.m.
     

    Sample volume
    Approximately 8-ounces is needed per test.  A one-gallon container is adequate to do all 22 chemistry tests available.
     

    Sample identification
    Water samples must have the name of the owner, or the submitter on the container. Multiple samples from different locations should be clearly marked.
     

    Sample temperature
    All samples should be kept cool until they are brought to the lab. Samples may be refrigerated or kept at a normal room temperature of less than 80 ° F until they are brought to the lab. It is not necessary to put them on ice. Samples should not be frozen.
     

    Time constraints
    All samples should be received in the lab within 24 hours of the sample collection time.  Some tests, such as hydrogen sulfide, chlorine, and pH, have critical time constraints.

    • Hydrogen sulfide:  Deliver to the lab as soon as possible after sample collection, preferably within one hour.  Fill the container to overflowing, with no air space at the top.  Cap with a tight fitting lid.  Ideally, H2S is tested at the source.
    • Chlorine:  Deliver to the lab as soon as possible- at least within four hours of sampling.
    • pH: For accurate pH values, the water sample should be tested as soon as possible after it is collected, at least within four hours of sampling.
    • Lead Analysis:  To detect maximum possible lead contamination, the water sample should be collected after the water has not been used for at least eight hours, but no longer than 18 hours.  For example, the water may be collected first thing in the morning, if the water has not been running through the night.