Nothing in this part shall be construed as:

(a) Affecting, modifying, diminishing, or otherwise impairing the sovereign immunity from suit enjoyed by Indian Tribes;

(b) Terminating, waiving, modifying, or reducing the trust responsibility of the United States to the Indian Tribe(s) or individual Indians. The Secretary must act in good faith in upholding this trust responsibility;

(c) Requiring an Indian Tribe to participate in self-governance; or

(d) Impeding awards by other Departments and agencies of the United States to Indian Tribes to administer Indian programs under any other applicable law.