Some tests require thermal preservation upon sample collection and your water sample may need to be refrigerated. If you received ice packs with your sample bottle, make sure to freeze the ice pack for 24 hours and use these when you return the sample to the EGLE Laboratory. Refrigerate your sample for 8 hours if possible if you will not be able to return it to the laboratory within 24 hours of collection. DO NOT freeze the sample. Samples received frozen are not acceptable for testing