SAN FRANCISCO — Attorneys for Southwestern Indian tribes urged a federal appeals court last week to block the proposed expansion of an Arizona ski resort they say already desecrates land they hold sacred and sullies their religious beliefs.

During the 70-minute hearing Thursday, a panel of the 9th U.S. Circuit Court of Appeals appeared skeptical about allowing Arizona Snowbowl to become the nation's first ski resort to use 100 percent reclaimed water to make snow.

A Hualapai tribe attorney argued that spraying snow made from treated sewage on the peaks, which they believe are spiritually significant, "is like putting a contaminated needle in your body containing poison."

Outside the hearing, dozens of American Indians, some wearing traditional garb, burned sage, drummed, chanted and held signs that read "Save the Peaks." Inside, the courtroom was filled to capacity, mostly with Indians, many of whom had traveled from Arizona to attend the hearing.

"Their plans to make snow, if allowed, would be cultural genocide," Kelvin Long, a Navajo who lives in Flagstaff, Ariz., said as he chanted here in front of the ornate courthouse.

The tribes say Snowbowl is an affront to their religion and its existence may have caused the Sept. 11 attacks and other universal calamities. The resort, one of two in the state, might go out of business because of a lack of snowfall.

The 777-acre resort rests on the western flank of the San Francisco Peaks that have spiritual and religious meaning to 13 tribes in the Southwest.

The resort wants to add a fifth lift, spray man-made snow and tear down and groom about 100 acres of forest to attract more skiers and increase the number of skiing days. U.S. District Judge Paul Rosenblatt of Phoenix ruled in January the tribes "failed to present any objective evidence that their exercise of religion will be impacted by the Snowbowl upgrades."

The tribes appealed to a three-judge panel of the San Francisco-based appeals court, which repeatedly questioned the proposal to spread snow created from treated wastewater.

Janice Schneider, a lawyer for the resort, told the court there would be 82 signs warning skiers the snow is generated from "reclaimed water."

But Judge William Fletcher wondered whether skiers would understand "that reclaimed water is treated sewage."

Fletcher and Judge Johnnie Rawlinson were doubtful because there aren't studies determining how the snow would affect skiers, although there are plenty of studies showing the snow would not harm the environment.