A burning oil and gasoline smell from Thursday's salvage yard fire of thousands of stacked cars caused aMandan nursing home to shut off its rooftop fresh-air vents Thursday afternoon.

Staff and residents started having issues with the "pretty strong" smell, said Michele Sondrol, director of nursing Friday.

"It drifted right over the top of us,"she said about the black smoke coming from Johnson's Wrecking, about three miles away.

Sondrol said smoke created a haze outside of the nursing home at 201 14th St. N.W., and although Medcenter Mandan Care Center became stuffy inside, staff only re-opened the vents for a short while around 7 or 8 p.m. and then turned the vents off again overnight. She said none of the 120 residents developed breathing problems or other issues because they acted quickly.

The North Dakota Department of Health issued an advisory for people with respiratory problems Thursday afternoon after the fire. The fire grew to about 15 acres in the salvage yard resulting in a black plume of smoke seen for miles that moved east over the Bismarck-Mandan area. The fire grew another 250 acres after it crossed the Heart River and consumed pasture land before firefighters stopped it. The cause of the fire remains uncertain.

The health department's advisory, continued on Friday, recommended that elderly people and those with respiratory problems stay inside.

"We were really lucky," said Dave Glatt, chief of the department's environmental health section.

"It was far enough away, a good wind,"said Glatt, giving two reasons why people didn't seem to be affected health-wise.

Glatt said departmentemployees with the water quality, air and waste divisions were at the still-smoldering fire site Friday to determine how best to stop the smoldering to end the release of particulates into the air and also to evaluate whether the salvage yard needed to change its operation.

The salvage yard, established more than 45 years ago, is about 1 1/2 miles west of Mandan on Highway 10 next to the Heart River.

Glatt said if a salvage yard were to try to locate in that location today, it would be "very difficult"to get governmental approval.

He said the existing business, however, still has to comply with environment regulations.

Glatt said the immediate concern is to snuff out still smoldering areas with soil, which he said yard owners Brian and Allan Johnson are working on now, and to build berms to prevent contaminants, in case of rain, from running into the river. But he said health department staff Friday also were looking at other issues.

He said a couple of years ago, his department warned, by mail, the Johnsons about the number of waste tires on site. Per state law, the yard was allowed only 1,300 tires, meaning "waste tires,"those in piles, and that limit was exceeded. Also, at that time, the Johnsons were warned that there needed to be improvements made to prevent stormwater run-off into the the river. He said at the time, the Johnsons responded with mitigation plans that were satisfactory to the department.

Glatt said Friday's assessment by health department staff would determine if those changes had been made to the state's satisfaction. He said a staff report on the matter will be available soon.

He said the Johnsons also have been instructed to do, with the help of a consultant, an environmental assessment of the burned area to determine the extent of soil and water contamination. Glatt thinks the Johnsons and their consultant, under the department's oversight, will collect samples, and Glatt said they should be able to get lab results on samples within a week or two.

The salvage yard is closed now, but plans to reopen Monday.

Kathleen Johnson, 39, Brian Johnson's wife, said Friday they hoped to reopen Monday, but are closed now for safety reasons.

"We still have trees burning, some falling,"she said.

She said as far as the cause, they were "really suspicious of a couple young males in yard." But in addition, a couple of Johnson employees reported having used a cutting torch that day, said Mandan Rural Fire Chief Lynn Gustin. And since fire investigators couldn't find any evidence of foul play, that's a possible cause, he said.

(Reach reporter Virginia Grantier at 250-8254 or at virginia.grantier@bismarcktribune.com)