The Department of Interior released a supplement to its Draft Programmatic Environmental Impact Statement for Solar Energy Development (Solar PEIS), which proposes solar energy zones on land managed by the Bureau of Land Management (BLM) in the U.S. Southwest.

The PEIS covers BLM land in Arizona, California, Colorado, New Mexico, Nevada and Utah. The supplement provides additional direction on the original PEIS, reducing the amount of land considered ideal for solar, and sets a variance procedure for BLM-managed and other public lands.

The supplement does some important things to improve over the original PEIS, according to the Sierra Club.

The organization has not chosen to endorse the PEIS supplement just yet, however.

The environmental organization will go over the PEIS very carefully before responding with comments, said Senior Representative Barbara Boyle, who focuses on renewable energy and public land use.

“We will be submitting detailed comments [after the review],” she said. “We do think the overall supplement is going in the right direction.”

Under the original PEIS, up to 22 million acres of public lands could have been considered for solar development. A full 677,400 acres were identified as potential solar energy zones.

The supplement reduces that to 285,000 acres.

“The biggest concerns we had about the original program is it was almost allowing solar development of lands without a due analysis,” Boyle said.

Without such analyses, it couldn’t be determined what the impact of solar would be on affected lands.

“One of the important elements of this revision is a clear focus on having the development go to solar zones, and on encouraging that through a faster permitting process and other incentives,” Boyle said.

The supplement’s clarification encourages solar to be built places where developers know they won’t run into a bunch of opposition from conservation groups, Native Americans and others, she said.

“It reduces the locations where solar energy can go and emphasizes the right places to put it,” Boyle said.

Such lands include previously disturbed lands, land near existing infrastructure with lower natural habitat and other natural resource values, she said.

The proposed lands and the variance process will help permitting be faster and less expensive, so projects can get underway quicker.

“Overall, it’s an improvement on the original draft; It’s more balanced,” Boyle said.

The supplemental PEIS, which will now go through a 90-day public review process, will make for a strong solar program, she said.