25 C.F.R. § 143.2 – Purpose.

(a) The purpose of the regulations in this part is to establish procedures for the assessment, billing, and collection of charges for goods/services provided to non-Federal users.
(b) The Assistant Secretary may sell or contract to sell to non-Federal users within, or in the immediate vicinity of an Indian Reservation (or former Reservation), any of the following goods/services if it is determined that the goods/services are not available from another local source or providing that goods/services is in the best interest of the Indian tribes or individual Indians. The goods/services include, but are not limited to:
1. (1) Electric power;
2. (2) Water;
3. (3) Sewage operations;
4. (4) Landfill operations;
5. (5) Steam;
6. (6) Compressed air;
7. (7) Telecommunications;
8. (8) Natural, manufactured, or mixed gas;
9. (9) Fuel oil;
10. (10) Landscaping; and
11. (11) Garbage collections.