在其在萨默维尔联合广场（Union Square）开设的第一个车站开业后，耗资23亿美元的绿线延期的建设正朝着其最终目的地。

The opening of the Union Square branch earlier this month marked a significant milestone for the project, first proposed approximately three decades before construction started in 2018—after many starts andstops.

GLX Constructors is now focusing on the completion of the second and final branch of the mega project later this year—the 3.7-mile Medford branch that will run from the Lechmere Station in East Cambridge to the Tufts University campus.

该设计建设项目由GLX Constructors（由Fluor Enterprises Inc.，Middlesex Corp.，Herzog Contracting Corp.和Balfour Beatty Infrastructure Inc.与STV Inc.担任首席设计师的合资企业。

Fluor的副总裁，GLX Constructors的项目经理Stephen Varnell表示，在视线的结束时，有一种成就感，尤其是考虑到大流行面临的挑战。

The project team was able to integrate social distancing and other preventative measures without stopping work.

In addition to laying new rail and systems, the joint venture built six new stations as part of the project, in addition to the relocated and revamped Lechmere Station in East Cambridge.

瓦内尔说：“该项目已经在书籍上已经三十年了。”“将铁路扩展到这些社区，其中一些从未有过铁路服务，这是一件很大的事情，而通过协证大流行的工作使这一成就变得更加重要。”

GZA Geoenvironmental Inc.为所有永久性结构提供了岩土设计，并设计了对开挖墙壁的永久和临时支持，同时还提供了基础建设期间的仪器监控和质量控制。

GZA项目负责人罗伯特·帕尔莫（Robert Palermo）指出，该项目是在茂密的城市环境中的现有铁路走廊中建造的，其住宅结构距离新的轻轨建筑仅几英尺远。他说，扩大现有的通行权需要建造超过三英里的挡土墙，并重建四个现有桥梁，并对另外两个桥进行修改。

“It was a really tight schedule and it required a lot of close coordination,” Palermo says. “It is a fascinating project and I am happy to look at it and say I was part of it.”

The design team also includes Arup, which is overseeing the design development, and testing and commissioning process. Arup originally served as an MBTA consultant in 2015 when the project ballooned $1 billion over budget. The design team helped the MBTA cut approximately $700 million from the project, including by designing less-elaborate stations. The MBTA’srevised program,2016年揭幕，恢复了该项目。

"The opening of this first segment of the Green Line extension is a testament to the incredible collective efforts and coordination," Jeff Tubbs, Arup principal and project director, said in a statement.

Behind the Scenes

虽然赛道上的工作已经完成，但施工人员将添加许多在新轻轨线上操作第二个也是最后一个分支所需的幕后系统，包括电力手推车，电信系统和电信系统的电气接线和安全摄像机系统。GLX项目的MBTA计划经理约翰·道尔顿（John Dalton）表示，电气安装工作和随后的测试不是“很浮华，但这是很多细节，需要时间。”

The rail systems can only be thoroughly tested after trains are placed on the tracks in the coming weeks. Additionally, while everything has been measured and remeasured, the final determination on whether the clearance space for the new cars meets fire and safety standards can only be fully tested with trains on the tracks.

澄清：尚未将铁路车引入2（Medford分支）测试计划中。一旦在接下来的几周中引入它们，他们就可以确认可以为乘客服务打开它。分支1（联合广场）全部开放并运行。

道尔顿说：“直到您介绍火车的最终变量之前，才能确认所有系统的行为，”

An array of local, state and federal elected leaders, T officials and executives from the joint venture, among others, marked the opening of Green Line service to Union Square with a ceremonial ribbon cutting on March 21.

预计新的绿线延长将每天吸引50,000名车手，有助于减少当地高速公路和道路上的拥塞和空气污染。

By the time the project is complete, the GLX project team will have laid down 100,000 railroad ties, 17 miles of track, nearly four miles of pilings, 22 million lb of steel girders, while also rolling out two miles of local pathways.

While most of the work is completed on the newly opened line, there remains a series of “punch list” items remaining on the project’s first phase, such as installing bus shelters and wiring the access control system for the bike storage system, the MBTA’s Dalton says

“Our objective was to get the trains into revenue service,” Dalton says.