BOSTON (AP) -- Wynn Resorts has bested Mohegan Sun for the lucrative Boston-area casino license, based largely on the strength of its $1.6 billion project's economic development potential.

The Massachusetts Gaming Commission voted 3-to-1 Sept. 16 to award the license to the Las Vegas casino giant, which wants to turn a heavily polluted, former chemical plant site on the Mystic River waterfront in Everett into a gleaming resort casino. The following day the commission confirmed the decision unanimously on a second vote.

Mohegan Sun had proposed a $1.1 billion casino at the Suffolk Downs horse racing track in Revere but had lost points for being a comparatively less ambitious facility more focused on drawing Boston-area residents and not encroaching on the customer base of its Connecticut casino.

The decision came after Wynn conceded to a number of significant requests the commission made, including proposing alternative designs for its 27-story glass hotel tower, which panel members had dismissed as generic. Wynn on Tuesday also agreed to pay more toward long-term plans to address traffic through Sullivan Square in nearby Boston.

Wynn had initially offered some $46 million in one-time and annual payments. It ultimately agreed to about $76 million in payments, including submitting to financial penalties in the event vehicle traffic is greater through the square than the company's projections.

Commissioners, who spent months reviewing the projects before publicly debating them in recent days, said both represented strong proposals. But they concluded the Wynn plan better fit what state lawmakers had envisioned when they passed legislation allowing for casinos in 2011.

Wynn, they noted, promised to pay workers better wages and proposed spending more in hard construction costs than Mohegan Sun.

The panel has said salaries at Wynn would be about a third higher than those at Mohegan Sun's casino and that Wynn's actual construction labor costs would amount to about $621 million while Mohegan Sun's would be about $293 million.

Commissioners also noted that opportunities to redevelop heavily polluted sites like the former Monsanto chemical plant are extremely rare.

Acting Gaming Commission Chairman James McHugh was the lone vote opposed. He said he had doubts the project could actually open on time, given the hurdles it faces in receiving government approvals and permitting.

Among the biggest issues are environmental remediation and traffic impacts to the neighboring city of Boston, where Mayor Martin Walsh has been staunchly opposed to the casino license process generally and the Wynn proposal specifically.