Outside, she found her car had been pushed 20 metres eastward from where she had left it parked. It now faced the opposite direction and had parts of its back end missing and a trail of debris in its wake.

Further on, a fully-laden Hino table top truck had come to a crashing halt, damaging a hydrant that now blasted water at its underbelly.

Miss McLean could hear the 21-year-old truck driver screaming for help, and ran to him. 

“We’ve opened the door and he’s just fallen out. He’s walked himself over but collapsed in my arms,”  Miss McLean, 18, of Shell Cove, told the Mercury. 

“He was in a lot of shock and pain. I kept him awake and with us until paramedics came.”

Miss McLean was among teen workers whose worried parents rushed to the Princes Highway restaurant after the runaway truck came down Mount Ousley Road, mounted a curb into the McDonald’s carpark and took out everything in its path, about 10.45am. 

Incredibly, the crash claimed only two other casualties, including an 18-year-old woman whose silver Honda CRV was collected as she approached the Princes Highway roundabout. The car spun off course, coming to rest over a burst water main. The teen later complained of tenderness around her neck and spine and paramedics took spinal precautions in transporting her to Wollongong Hospital. 

A 61-year-old woman was the most seriously injured. 

Unseen by Miss McLean, the woman’s white Suzuki Vitara became pressed nose-to-nose against the wayward truck. For a terrifying few seconds, it was forced backwards away from the McDonald’s drive-thru and through the steel bar fence of the neighbouring Northgate apartment complex. Its front end crumpled in as the truck inched towards its resting point. 

A Northgate resident, Julie Colla, could only look on as the SUV was overpowered, its driver helpless at the wheel. 

“I can still visualise it crunching all up,” a distressed Ms Colla said afterwards.  

“The police don't know if she’s OK, and I'm praying because it could have easily been me and I really want her to survive.” 

The Suzuki also came to rest over the burst hydrant, with the injured woman doused as passers-by and emergency service workers came to her aid.  

NSW Ambulance’s Illawarra district inspector Terry Morrow said the woman was trapped for 15-20 minutes with a concussion, several broken ribs and pelvic injuries. 

All three injured were taken to Wollongong Hospital, where they remained Monday afternoon in a stable condition. 

Insp Morrow said the truck driver had a pre-existing back injury that was aggravated in the crash. 

He appeared “confused and disorientated” and “emotionally distressed” in the aftermath, and gave no word to first responders of what had caused the crash. 

Emergency services workers have marveled at how few casualties resulted from the crash, in a car park full of vehicles. 

“It had the potential for great amounts of … people [being injured], however I think because the people were in McDonald’s itself … they were empty cars that were hit,”  Insp Morrow said.

“Approximately 10 years ago I came to a similar situation at this location, where a truck had gone through the drive-thru and there were a number of people seriously injured.

“However these people have been very, very fortunate. They’ve got away only minor, really, injuries, under the circumstances.” 

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The truck driver was working as an independent contractor for a Wetherill Park-based taxi truck business, DSE. 

The Mercury understands the driver collected a load of building supplies from a Sydney site Monday morning before making the drive south. 

DSE general manager Rocky Nicotra said the company would carry out an internal investigation into the crash, and had yet to establish what went wrong. 

“What I'm hearing is that the load was properly restrained; I don’t know what the weight was,” he said, Monday afternoon. 

The truck is the second to come unstuck on the mountain and plough through the McDonald’s grounds since December 2006, when 15 people were rushed to hospital in the aftermath of a similar disaster. 

The site’s uneasy history will be on the mind of workers like Miss McLean, whose voice shakes as she prepares to depart the carpark with her mother on Monday. 

“I was about to finish my shift when this happened, so a few minutes later, I would have been involved,” she said. 

“I think something needs to be done for our safety. It could have been a lot worse.” 

The restaurant was closed throughout Monday, resuming trade about 6pm Monday. 

Police have taken a mandatory blood sample from the truck driver. 

The truck has been towed from the scene, to be mechanically examined. 

Anyone who may be able to assist with the police investigation is encouraged to contact Crime Stoppers on 1800 333 000.