The Arizona Corporation Commission recently approved a permit for SRP’s power plant expansion near Coolidge.

That’s after the utility came to an agreement with members of the historic Black community of Randolph.

But a conservation group has challenged the decision.

Last week, the Sierra Club filed suit against the commission in an effort to block the expansion.

It says the gas-fired plant would contribute to pollution and climate change, and that the utility failed to disclose details of the agreement it made with Randolph residents.

SRP said in a statement that the nonprofit’s arguments are without merit and should be rejected. The utility also said the expansion is necessary to meet growing demands for power in the Valley.

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