James Jacks, an ironworker with Oregon-based West Side Iron, attaches a cable to a 150-ton steel girder, preparing it for installation Thursday at the state Highway 500 and St. Johns Boulevard interchange project in Vancouver. As construction work continues to pick up steam, crews this week tackled some of their heaviest lifting yet at the intersection of St. Johns Boulevard and state Highway 500 in Vancouver.Using two cranes, workers hoisted huge steel girders next to the highway, laying them parallel to the thoroughfare. The Vancouver-made beams — each weighing some 150 tons and stretching more than 200 feet when assembled — will support new ramps connecting the highway and St. Johns. The work is part of a $48 million project converting the signalized intersection into a freeway-style interchange. When it’s done, St. Johns will travel up and over the highway on a new bridge.Crews placed the first large girder section Wednesday, installing it on the south side of the highway east of St. Johns. Another followed Thursday, though the second installation proved a more difficult task. Part of the challenge is having less room to maneuver with the first large section already in place, said Lori Figone, a Washington State Department of Transportation engineer and project manager.The job could get even more complicated next week, when crews place two more steel girders on the north side of the highway. In addition to Burnt Bridge Creek and traffic they’re already working around, cranes will have to keep a close eye on large power lines overhead, Figone said.“It’s tight,” she said.The project has squeezed traffic at the busy intersection for months. Speed limits have been reduced. St. Johns has been diverted from its original alignment. All turns from the highway to St. Johns have been prohibited.