A proposed $1 billion Amazon facility in Holbrook could become the largest Amazon site on Long Island - and one of the company's most significant logistics hubs in the Northeast.

Plans call for a 4.2 million-square-foot package origination center near Sunrise Highway and Beacon Drive. If approved, the facility would be Amazon's 10th location on Long Island but its first package origination center, serving destinations throughout the Northeast.

Residents who live near the proposed site say traffic is already a concern.

"They're going to have to figure out the traffic, though. The entrance to this place is a nightmare getting in," said Brian Honahan, of Mount Sinai.

Amazon says the facility would help speed up deliveries for customers across the region. However, the project would also add significant truck traffic, with an estimated 300 trucks entering and exiting the site daily.

According to Amazon, the truck traffic estimate is spread over a 24-hour period.

"We're working to make sure that we can either maintain or improve traffic service throughout this corridor as a result of the project," said Brad Griggs, Amazon's director of economic development for the Northeast, Mid-Atlantic, and Canada regions.

Amazon says it has submitted a traffic study to the Town of Islip as part of its application process. The study includes proposed infrastructure improvements intended to address traffic concerns in the area.

If the project receives approval, Amazon estimates construction would take between 18 and 24 months. The company says the facility would create approximately 1,000 jobs on Long Island.

An Islip Town spokesperson said Amazon's proposal must undergo federal, state and local reviews, including environmental impact assessments, before any final approvals are granted.