The Congress finds that—
in recognition of the need to provide increased protection for the monument, the boundaries of Tucson Mountain unit were expanded in 1976, and the boundaries of Rincon unit were expanded in 1991;
the Tucson Mountain unit continues to face threats to the integrity of its natural resources, scenic beauty, and habitat protection for which the unit was established;
these threats impede opportunities for public enjoyment, education, and safety within the monument, as well as opportunities for solitude within the wilderness areas of the monument designated by Congress in 1976;
the residential and commercial growth of the greater Tucson, Arizona metropolitan area is causing increasing threats to the monument’s resources; and
the Tucson Mountain unit should be enlarged by the addition of adjacent lands of National Park caliber and Saguaro National Monument should be afforded full recognition and statutory protection as a National Park.