New York State Police Thursday tried to trace Diane Schuler's route from the Tappan Zee Bridge to the scene of the fiery Taconic State Parkway crash that killed eight Sunday, but acknowledged they may never know her exact path in those last 30 minutes.

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The exercise yielded no new clues to the mysterious wrong-way collision, said investigators who called the route "speculative.” But they said the 11-mile drive solidified their belief that Schuler stopped in a pull-off area on the New York State Thruway after crossing the Tappan Zee Bridge into Westchester County and called her brother Warren Hance at about 1 p.m. to say she was sick.

The route  --  two miles east on the Thruway to Interstate 287, then north for eight miles on the Saw Mill River Parkway before exiting onto Pleasantville Road and going a mile-and-a-half north to a Taconic exit ramp  --  took about 25 minutes Thursday, said State Police Lt. Dominick Chiumento.

That makes it plausible for Schuler to have reached the Taconic by 1:35 p.m. after calling her brother, Chiumento said.

This is the junction of the northbound exit ramp of the Taconic State Parkway at Pleasantville Rd. in Pleasantville where the minivan driven by Diane Schuler, 36, entered the wrong direction, southbound in the northbound lanes. The van burst into flames Sunday as the vehicle collided with two northbound 1.7 miles south of here as she was driving home from a Sullivan County camping trip with her two children and three nieces, police said at a press conference Monday, July 27, 2009. The crash killed Schuler, her daughter, Erin 2, and Schuler's nieces, Emma Hance, 9, Alison Hance, 7, and Kate Hance, 5. Killed in a second vehicle were Guy Bastardi, 49; his father, Michael Bastardi, 81; and a friend, Daniel Longo, 74, all of Yonkers, who were heading northbound when Schuler's van collided with the vehicle. The lone survivor of the crash was Schuler's 5-year-old son, Brian. Photo by Craig Ruttle Photo Credit: NEWSDAY/CRAIG RUTTLE

The Ford minivan she was driving then entered the Taconic via the exit ramp and went 1.7 miles south into northbound traffic, causing a head-on collision with an SUV.

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Schuler, of West Babylon, was killed, along with her daughter, her brother Warren Hance's three daughters, who lived in Floral Park, and three men from Yonkers in the SUV. The Long Island families were buried yesterday after a funeral Mass.

Schuler's son, Bryan, 5, was the only survivor. He was recovering yesterday at Westchester Medical Center in Valhalla, N.Y., said a hospital spokesman who has declined to release the boy's condition at the family's request.

More than a dozen witnesses who watched Schuler driving the wrong way have stepped forward, but none who saw her before getting on the Taconic. Police asked anyone who saw the red minivan on the Saw Mill or Thruway to call the Hawthorne, N.Y., barracks at 914-769-2600.

Police don't know why Schuler  --  driving her children and nieces back to Long Island from an upstate camping trip  --  turned north after calling her brother, instead of going south toward home. Her brother had asked her to pull over and wait for him.

One investigator, Robert C. Bennett, said police have discussed the possibility that Schuler went north to turn around and return to the pull-off where she left her cell phone behind on a concrete barrier.

"It's speculation,” Chiumento said. "We won't ever know.”

There are security cameras located at the pull-off where Schuler called her brother. Police said Thursday there was no footage of Schuler but declined to say why.

Chiumento said police do not know if Schuler had a global positioning system device in the car, in part because investigators have waited to interview her family until after Thursday's funeral.

With Matthew Chayes

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