The Department may reject a Tribe's final offer for any of the following reasons:

(a) The amount of funds proposed in the final offer exceeds the applicable funding level to which the Tribe is entitled;

(b) The subject of the final offer is an inherent Federal function that cannot legally be delegated to the Tribe;

(c) Carrying out the PSFA would result in significant danger or risk to public health or safety; or

(d) The Tribe is not eligible to participate in self-governance under section 23 U.S.C. 207(b).