(CNN) -- Firefighters have stopped the northward advance of the second-largest wildfire in recorded Arizona history and are now focusing on its eastern flank, crossing the New Mexico border to build suppression lines meant to starve the flames into submission, authorities said Monday.
Light winds after dark and an atmospheric inversion will hold smoke at the surface overnight going into Tuesday morning, authorities said.
The Wallow Fire has burned 706 square miles, officials said Monday, up from 694 square miles the day before. The fire remains about 10% contained.
Calmer winds were helping firefighters get the upper hand on the fire, which has been burning since late May, said Jerome MacDonald, the operations chief for the Southwest Incident Management team.
Efforts to return residents to Greer, part of which was burned in the fire, are under way, said Fire Chief Mark Wade.
"Greer is not as bad as a lot of people are making it sound," he said.
But he warned that there are dangerous obstacles that must be cleared and utilities to be restored before residents can be allowed back in.
Residents were already moving back to the towns of Springerville, Eagar and South Fork after authorities lifted evacuation orders on Sunday.
Authorities warned residents of the towns, about 170 miles east-northeast of Phoenix, that air quality could continue to be a problem, and food in refrigerators may have spoiled.
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But officials with both cities disputed a state suggestion that water supplies might be contaminated.
"Our water is pure, and it always has been," said Springerville town manager Steve West.
Vicki Walker of Eagar has made up her mind to return, according to her husband, Kelvin. She, her daughter and her grandson were leaving Phoenix for home Monday morning, Kelvin Walker said.
"She's elated to be getting back this soon," said Walker, who stayed behind while his family evacuated.
The Wallow Fire is the second-largest recorded fire in state history, having burned across a land mass roughly equivalent to an area one and a half times the city of Phoenix.
The 2002 Rodeo/Chediski fire, Arizona's largest recorded wildfire, burned more than 731 square miles of eastern Arizona.
Fire officials said Sunday that they had turned a corner in stopping the fire, which started as May 29 in the Apache National Forest, according to authorities.
Walker said he remained in part to keep an eye on the family's two-acre homestead. However, the main reason he didn't evacuate with his family was because his elderly aunt and uncle refused to budge, and he felt compelled to stay and look after them.
"It was really strange," Walker said. "If you chose to stay rather than evacuate, you had to sign a waiver and say you would not leave your property."
Walker didn't stay home. He ventured out into the ghost town, not to disobey but to help out, he said.
He said he took training to become a runner for firefighters on the front lines. Among them is his 26-year-old son, Kyran, who is a seasonal firefighter for the U.S. Forest Service, Walker said.
"He was one of the first responders. He's been working 12 to 16 to 18 hours a day since the fire started," Walker said. "I stayed home and fed him every night. I think he took (the fire) fairly personal."
So did Walker's neighbors. Before evacuation, many left signs in the front yards in support of the firefighters.
"The signs said things like 'We love you. We appreciate you. Be safe!' " Walker said.
On Sunday, according to CNN affiliate KNXV, a flashing sign posted on the road into Springerville read, "We missed you. Welcome home."
Electricity has been restored to the towns of Nutrioso and part of Alpine, southeast of Greer.
More than 100 law enforcement officers are working with the incident to ensure public and firefighter safety, as well as protect residents' property during evacuations, authorities said Monday evening.
CNN's Phil Gast and journalist Craig Johnson contributed to this report.
