PORTLAND — Baxter Academy for Technology and Science passed a city inspection of its 54 York St. facility Wednesday after lingering fire safety and electrical concerns caused the new charter school to fail at least two previous reviews.

The passing marks clear the way for Baxter Academy to acquire its occupancy permit and receive its inaugural class of approximately 135 students on Sept. 4, a timeline school officials have always maintained was not in jeopardy.

Tammy Munson, head of Portland’s inspection division, confirmed the school’s inspection passage to the BDN just after noon Wednesday.

“It feels great to get that off the table and to get down to important issues about how we structure our curriculum and teach our kids,” said Carl Stasio, executive director of the academy, Wednesday afternoon.

Stasio’s belief that the school would be opened on time was unwavering in recent months despite the facility’s fire and electrical code setbacks. He told the Bangor Daily News after the school failed its previous city inspection on Aug. 21 that he was “not even a little bit” concerned the need for additional repairs of the century-old building would force academy leaders to push back the first day of school.

Baxter Academy — which plans to build a strong science, technology, engineering and mathematics, or STEM, curriculum around hands-on student projects — is one of five institutions approved by the Maine Charter School Commission under a 2011 law legalizing charter schools. It is the first charter school in Maine’s largest city.

“The opportunity to start up a new school in such an important area — STEM is extraordinarily important for Maine kids — is very exciting,” said Stasio, who served as headmaster at Thornton Academy in Saco for 26 years before retiring and taking the Baxter position in the spring. “This is just one of those opportunities of a lifetime.”

Stasio said the school’s first students will be involved with two days of “team building” exercises on Sept. 4-5 to start the school year, with the first of those days scheduled to take place at Fort Williams Park in nearby Cape Elizabeth.

“These kids haven’t been together for school. Some of them may know each other, but this is not like a traditional transition from eighth grade to high school. These kids are coming from 35 different cities and towns,” he said. “It’s important that we build teams, certain behavioral norms and social norms. Much of the first year is going to be about developing the culture of the school.”

Baxter Academy has been the focus of regular controversy in the 18 months prior to its scheduled opening. In the spring and summer of 2012, Portland Mayor Michael Brennan vocally urged the Maine Charter School Commission not to approve the school’s application, saying it would siphon public education funds from other Portland-area public schools.

This year, academy board members threw out the school’s founding executive director and then engaged in a legal battle over whether the founder or institution retained control over the school’s website and much of its early documentation.

Last month, Maine Senate President Justin Alfond, D-Portland, blasted school leaders for hosting an event by the conservative Maine Heritage Policy Center. Alfond indicated that he saw the move as a sign the academy was aligned politically with the conservative group, an allegation Stasio adamantly denied. Republican Gov. Paul LePage responded to Alfond’s criticism in a blistering letter to the Portland Democrat accusing him of politically motivated attacks against the school.

Portland-based Richard Renner Architects lists Baxter Academy among the firm’s current clients.