Veteran corporate executive Luis M. Ramirez began a new role on Sept. 12 as general manager and CEO of the Massachusetts Bay Transit Authority, which runs Boston regional transit, despite controversy over his lack of public transit management experience and financial scrutiny of Global Power Equipment Group, an engineer and manufacturer of which he was CEO until 2015, say media reports.

The firm now is under a U.S. Securities and Exchange Commission accounting audit, but there is no direct link to Ramirez, says The Boston Globe. Ramirez also was a General Electric corporate vice president and CEO of its energy industrial solutions unit. According to the Globe, he has managed major infrastructure projects in the energy sector.

Ramirez, the fifth person to lead MBTA under Massachusetts Gov. Charlie Baker (R), replaces interim chief Steven Poftak, who returns to a position on the MBTA control board. In an agency-released statement, Poftak noted his successor’s “deep exposure to a range of challenges and constituencies and proven leadership skills.” MBTA now is focused on fixing operations and investment in infrastructure repair.

Johan Karlström will step down next April as president and CEO of Skanska AB, the Sweden-based contractor said on Sept. 13. Then, he will be a “senior adviser” until January 2019, which Reuters said was the original date of his contractual CEO resignation. Skanska said it would name a new CEO by year’s end. Karlström, 61, who joined the firm in 1983, has been in his roles since 2008. Skanska ranks at No. 17 on ENR’s list of the Top 250 Global Contractors, reporting $15.5 billion in 2016 global revenue.

U.K. building contractor Forrest Construction named as its new CEO, effective in October, Mark Nicholson, a regional managing director at British contractor Carillion. Nicholson also formerly held managing director roles at Bovis Lend Lease and Jarvis Construction.

PC Construction, South Burlington, Vt., has elevated Senior Vice President Jay Fayette to chief operating officer and named four new vice presidents: Eve Norris, Kevin Morrissey, Nicole LaBrecque and Chet Layman. The employee-owned contractor, which ranks at No. 147 on ENR’s list of the Top 400 Contractors with 2016 revenue of $560.1 million, foresees that total rising to $650 million this year.

William “Bo” Mills last month was elected president of the 30,000-member American Public Works Association. He is public-works director for the city of Germantown, Tenn., and former president of the state APWA chapter. The national group also elected Jill Marilley, an HDR senior construction manager in Bellevue, Wash., as its president-elect.

Jon Taylor, John Brown and Ralph Govan, partners of Toronto construction-management firm Govan Brown, have joined New York City-based CM and building contractor Structure Tone as employee-owners, following the U.S. firm’s Sept. 12 buy of the Canadian company. Structure Tone became an employee-owned firm under an ownership change that took effect Jan. 1. Govan Brown will remain a “legal operating entity,” says a Structure Tone spokeswoman.

Nashville-based Hardaway Construction Corp. has hired David Frazier as president and operations manager. Stan Hardaway remains CEO. Frazier had been senior construction manger at builder D.F. Chase, also in Nashville.

Anthony B. Bouchard was named president and chief operating officer of CDM Smith, effective on Jan. 2, the Cambridge, Mass., design firm said on Sept. 18. He succeeds Timothy B. Wall, who becomes chairman and CEO, also at that time. Bouchard had been CDM Smith’s North America unit president.