Art 1, Sec. 8 US CONstitution, Powers of CONgress:

This issue is a very difficult issue. It is a 10th Amendment issue for the Federal Government. And it is a water-agreement issue for California, thereby possibly making it an Federal Government interstate issue.

First, does the Federal Government have authority to remain in control of lands within any State when the lands have not been ceded to the Federal Government by the State? If there is not some pre-statehood agreement to such effect, set in place as a prerequisite for statehood, generally the Federal Government loses the land-control issue.

With Arizona, things might be different because of the Colorado River that provides water to California. Depending on the wording of the agreements between Arizona and California for water rights, the whole thing might be considered interstate commerce, and fall under the Federal Government Commerce Clause. However, to what extent should the Fed Gov control the land and not simply regulate the free flow of water?

All the talk about Arizona being able to take care of the Grand Canyon is garbage talk. Outside of water rights, and outside of some statehood agreement that Fed Gov control lands within Arizona, if the land has not been ceded to the Federal Government, the land belongs to Arizona. If Arizona shuts down Grand Canyon National Park, it is within her rights as a Sovereign State.

If Arizona is having problems taking care of land that it owns, financially? Ownership and use of Grand Canyon lands should help to provide the financing necessary to take care of the lands. But who is to judge how Arizona is supposed to take care of its lands? Not taking care of Arizona lands may be the precise way that Arizona DOES take care of her lands. Other States and the Federal Gov have no rights here except the right to yakketty-yak allowed them by the 1st Amendment.

It's about time that Arizona asserts her rights in this area. And other states that find themselves in similar positions with the Federal Government regarding their lands, should assert their rights, as well.

In Arizona, this has been attempted before. Let's hope it wins this time.
 

As it should be.  Article 1, Section 8 of the CONstitution prohibits the US Government from owning lands beyond that necessary for its own buildings. Not, of course, that this matters.