1. (a) The rules of this part shall apply to PWSs that are non-community water systems as defined by Env-Dw 103.37, which comprise:

   1. (1) Transient non-community (TNC) water systems, which serve a transitory non-residential population, such as restaurants, motels, and campgrounds, and serve at least 25 persons in a transitory setting for more than 60 days each year; and
   2. (2) Non-transient non-community (NTNC) water systems, which serve a regular but non- residential population such as schools, workplaces, and day care centers, and serve the same 25 people, or more, over 6 months per year.
2. (b) Criteria that only apply to a particular type of non-community water system shall be as noted in each specific rule requirement.
3. (c) For existing non-community water systems that propose to expand or be modified, and those required by the department to make water system improvements, including new wells, the design criteria of this part shall apply only to the component(s) of the PWS affected by the proposed expansion, modification, or both. For the purposes of this part, “modified” means altered, added to, expanded, or enlarged.
4. (d) Existing non-community water systems that have not previously been approved pursuant to this part, shall obtain approval in accordance with this part.
5. (e) Non-community water systems that are being reactivated, if they have been inactive for 6 months or more, shall comply with this part. This shall not include PWSs that normally open and shut down for seasonal operations.

Source. (See Revision Note at part heading for Env-Dw 406) #10613, eff 6-1-14; ss by #14158, eff 12-25-24 (formerly Env-Dw 406.02)