If your plant will be using water supplied by a municipal water supply system (such as city, county, or other public water system) you must obtain a letter issued by the municipality, or your state or county public health service.
If you will be using a private water supply (such as a private well), the letter must be issued by your state or county public health service. If the water is supplied from private wells, the letter must state that the wells are on the premises of the establishment and are effectively protected from pollution. The letter should identify the source and state that (a) the source is approved and (b) the water is potable and meets tests prescribed by the Drinking Water Standards of the Environmental Protection Agency.
In addition to the water approval letter, a current acceptable water laboratory sample report (“water potability certification”) must be on file before inspection is granted.
Resource
Sample Letter for Approved Municipal Water Supply
This sample also contains a sample letter for an approved sewage system