The Arizona State Land Department has found that the proposed Florence Copper Project presents "no substantial threat" to the environment and the economic benefits outweigh other concerns, according to a story in the Casa Grande Dispatch.
The article quotes opponents to the project, led by owners of nearby lands intended for residential and commercial development, who argue that State Lands has a financial interest in the project, so their decision is not independent. The in situ mining project includes 160 acres of state trust lands out of the 1,342 total acres, expected to generate $100 - $150 million in royalties to the trust fund over 20-25 years. [right, injection well for in situ project. Credit, Curis Resources]
They also argue that the value of over 3,000 acres of nearby state trust lands will be "drastically diminished" by the copper project and that violates the departments obligation to maximize revenue for its beneficiaries.
My calculation is that for State Land to walk away from $100-150 million in order to purportedly maintain the property values on another 3,000 acres, those lands would have to lose value at the rate of $33,000 - $50,000 per acre.